Most studies in the USA of vegetation alteration and human impact along trails have been located in large western wilderness areas. The objective of this study was to determine vegetation changes occurring along trails in an eastern ecosystem supporting second-growth deciduous forest. The location of this study was Shenandoah National Park in Virginia, which has a long history of trail use by humans. Located in different sections of the park, ten trails were chosen as study areas. In each, transects were established to measure ground flora in trailside, transition, and undisturbed areas perpendicular to the trail. Field data were collected on frequency, life-form, and percent cover for ground flora of 25 cm or less in height. Cover and species diversity increased toward the trail in eight out often cases. Competition for light and resistance to trampling were thought to influence the occurrence of plants along the transect. Plants found along the trail border were represented by low growthforms, early blooming, or graminoid characteristics, and hemicryptophyte, therophyte, or chamaephyte life-forms. Plants found in the undisturbed zone were represented by scattered cover and frequency, woody growth forms or delicate herbaceous forms, and phanerophyte or geophyte life-forms.
","publisher":"Elsevier","doi":"10.1016/0006-3207(89)90119-5","usgsCitation":"Hall, C.N., and Kuss, F.R., 1989, Vegetation alteration along trails in Shenandoah National Park, Virginia: Biological Conservation, v. 48, no. 3, p. 211-227, https://doi.org/10.1016/0006-3207(89)90119-5.","productDescription":"17 p.","startPage":"211","endPage":"227","costCenters":[{"id":37280,"text":"Virginia and West Virginia Water Science Center ","active":true,"usgs":true}],"links":[{"id":356755,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Virginia","otherGeospatial":"Shenandoah National Park","volume":"48","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5c112c44e4b034bf6a822607","contributors":{"authors":[{"text":"Hall, Christine N.","contributorId":207287,"corporation":false,"usgs":false,"family":"Hall","given":"Christine","email":"","middleInitial":"N.","affiliations":[],"preferred":false,"id":743448,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kuss, Fred R.","contributorId":207288,"corporation":false,"usgs":false,"family":"Kuss","given":"Fred","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":743449,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70210577,"text":"70210577 - 1989 - The crustal structure of the Wrangellia Terrane along the East Glenn Highway, eastern‐southern Alaska","interactions":[],"lastModifiedDate":"2020-06-10T16:51:12.301168","indexId":"70210577","displayToPublicDate":"1989-06-10T11:42:19","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2314,"text":"Journal of Geophysical Research B: Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"The crustal structure of the Wrangellia Terrane along the East Glenn Highway, eastern‐southern Alaska","docAbstract":"Recently acquired seismic refraction data from eastern‐southern Alaska provide new information on the structure and composition of the Wrangellia and adjacent terranes. The data comprise a 160‐km‐long refraction profile along the East Glenn (Tok‐Cutoff) Highway that was collected as part of the U.S. Geological Survey's multidisciplinary Trans‐Alaska Crustal Transect program. The upper 3 km of the Wrangellia terrane and associated rocks is characterized by low compressional wave velocities (Vp = 1.9, 3.3, 4.6, 5.6 km s−1) and high‐velocity gradients common to most onshore seismic refraction profiles. There is also clear seismic expression of the West Fork fault system as a steep, down‐to‐the‐southwest fault that separates the Peninsular terrane to the southwest and the metamorphic complex of Gulkana River to the northeast. In contrast, no seismic expression occurs for the Paxson Lake fault, which separates the Wrangellia terrane from the metamorphic complex of Gulkana River. Adjacent to the Denali fault, within the Wrangellia terrane, two high‐velocity bodies (Vp = 6.6 km s−1) occur in the upper crust. One of these extends to ∼10‐km depth and correlates with a late Paleozoic dioritic complex, suggesting that the Wrangellia terrane is at least 10 km thick in this part of Alaska. From 5 to 23 km depth, the crust appears seismically homogeneous, with velocity increasing from Vp = 6.2 to Vp = 6.6 km s−1. Beneath this level, the crust is less well resolved, although evidence exists for a low‐velocity zone between 23 and 26 km and a possible southwest dipping interface at 35 km. No identifiable mantle refraction or reflection is observed, possibly indicating a crust as thick as 55 km. The relatively low seismic velocities in the upper 23 km of the crust compare favorably with laboratory‐measured velocities on pelitic schists and intermediate‐composition plutonic rocks (granites and granodiorites), both of which are recognized in Wrangellia. We interpret the seismic velocities to indicate that silicic‐to‐intermediate‐composition rocks are important constituents of the basement of this part of Wrangellia. Geologic evidence indicates that the Alaskan part of the Wrangellia terrane is a Paleozoic and Mesozoic island arc: our seismic evidence indicates it may have been built mostly on continental crust as opposed to the fragment of Wrangellia from Vancouver Island which was probably built on oceanic crust.
","language":"English","publisher":"Wiley","doi":"10.1029/JB094iB11p16037","usgsCitation":"Goodwin, E., Fuis, G.S., Nokleberg, W.J., and Ambos, E.L., 1989, The crustal structure of the Wrangellia Terrane along the East Glenn Highway, eastern‐southern Alaska: Journal of Geophysical Research B: Solid Earth, v. 94, no. B11, p. 16037-16057, https://doi.org/10.1029/JB094iB11p16037.","productDescription":"21 p.","startPage":"16037","endPage":"16057","costCenters":[{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true}],"links":[{"id":375494,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Alaska","otherGeospatial":"Eastern- Southern Alaska","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -153.28125,\n 57.51582286553883\n ],\n [\n -132.1875,\n 57.51582286553883\n ],\n [\n -132.1875,\n 64.51064316846676\n ],\n [\n -153.28125,\n 64.51064316846676\n ],\n [\n -153.28125,\n 57.51582286553883\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"94","issue":"B11","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","contributors":{"authors":[{"text":"Goodwin, E.B.","contributorId":225177,"corporation":false,"usgs":false,"family":"Goodwin","given":"E.B.","email":"","affiliations":[],"preferred":false,"id":790653,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Fuis, Gary S. 0000-0002-3078-1544 fuis@usgs.gov","orcid":"https://orcid.org/0000-0002-3078-1544","contributorId":2639,"corporation":false,"usgs":true,"family":"Fuis","given":"Gary","email":"fuis@usgs.gov","middleInitial":"S.","affiliations":[{"id":237,"text":"Earthquake Science Center","active":true,"usgs":true}],"preferred":true,"id":790654,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Nokleberg, Warren J. 0000-0002-1574-8869 wnokleberg@usgs.gov","orcid":"https://orcid.org/0000-0002-1574-8869","contributorId":2077,"corporation":false,"usgs":true,"family":"Nokleberg","given":"Warren","email":"wnokleberg@usgs.gov","middleInitial":"J.","affiliations":[{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true}],"preferred":true,"id":790655,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Ambos, E. L.","contributorId":23957,"corporation":false,"usgs":true,"family":"Ambos","given":"E.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":790656,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70209350,"text":"70209350 - 1989 - Evolution of the western part of the Coast plutonic–metamorphic complex, South-Eastern Alaska, USA: A summary","interactions":[],"lastModifiedDate":"2020-04-30T17:12:11.527112","indexId":"70209350","displayToPublicDate":"1989-04-01T13:37:36","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1785,"text":"Geological Society Special Publication","active":true,"publicationSubtype":{"id":10}},"title":"Evolution of the western part of the Coast plutonic–metamorphic complex, South-Eastern Alaska, USA: A summary","docAbstract":"The western Cordillera of North America extends for over 6000 km from the tip of Baja California to the Alaska Range. It includes a wide variety of metamorphic and plutonic terrains, but none is more spectacular scenically or geologically than the Coast plutonic-metamorphic complex (Brew & Ford 1984) of western Canada and south-eastern Alaska. This report briefly describes the evolution of the western part of the complex, integrating information from the deformational, plutonic and metamorphic events. Most of the original studies are reported by the authors in U.S. Geological Survey Circular numbers 733, 751, 823-B, 868, 939, 945, 967 and 978, and are not cited specifically here. This summary does not contain either a comprehensive bibliography or a comparison of the metamorphic histories of south-eastern Alaska with the adjacent parts of British Columbia.
The Coast plutonic-metamorphic complex is here divided into three major elements: the western metamorphic, the central granitic and the eastern metamorphic zones (Fig. 1). The western metamorphic belt is extremely long (900 km), and narrow (7–25 km). It consists of regional dynamothermally and regional thermally metamorphosed rocks with mineral assemblages ranging from prehnite-pumpellyite to upper amphibolite facies, scattered mesozonal to epizonal granitic bodies, and a few concentrically zoned mafic-ultramafic masses. The metamorphic grade and the amount of deformation increase from south-west to north-east, culminating at, or slightly to the north-east of, the ‘great tonalite sill’: a remarkable 700-km-long, 3- to 25-km-wide vertical to northeast-dipping belt of mostly syntectonic plutons of approximately the same age, composition and structural
","language":"English","publisher":"Geological Society of London","doi":"10.1144/GSL.SP.1989.043.01.40","usgsCitation":"Brew, D.A., Ford, A.B., and Himmelberg, G.R., 1989, Evolution of the western part of the Coast plutonic–metamorphic complex, South-Eastern Alaska, USA: A summary: Geological Society Special Publication, v. 43, p. 447-452, https://doi.org/10.1144/GSL.SP.1989.043.01.40.","productDescription":"6 p.","startPage":"447","endPage":"452","costCenters":[{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true}],"links":[{"id":373717,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Alaska","otherGeospatial":"Southeastern Alaska","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -135.087890625,\n 59.5343180010956\n ],\n [\n -138.076171875,\n 58.53959476664049\n ],\n [\n -133.2421875,\n 54.16243396806779\n ],\n [\n -129.814453125,\n 55.27911529201561\n ],\n [\n -135.087890625,\n 59.5343180010956\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"43","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"Brew, David A. dbrew@usgs.gov","contributorId":3244,"corporation":false,"usgs":true,"family":"Brew","given":"David","email":"dbrew@usgs.gov","middleInitial":"A.","affiliations":[],"preferred":true,"id":786246,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ford, A. B.","contributorId":44924,"corporation":false,"usgs":false,"family":"Ford","given":"A.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":786247,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Himmelberg, G. R.","contributorId":27106,"corporation":false,"usgs":true,"family":"Himmelberg","given":"G.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":786248,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70016050,"text":"70016050 - 1989 - Supplemented graphic correlation; a powerful tool for paleontologists and nonpaleontologists","interactions":[],"lastModifiedDate":"2025-03-12T15:49:52.512957","indexId":"70016050","displayToPublicDate":"1989-04-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3000,"text":"Palaios","active":true,"publicationSubtype":{"id":10}},"title":"Supplemented graphic correlation; a powerful tool for paleontologists and nonpaleontologists","docAbstract":"No abstract available.
","language":"English","publisher":"GeoScienceWorld","doi":"10.2307/3514601","usgsCitation":"Edwards, L.E., 1989, Supplemented graphic correlation; a powerful tool for paleontologists and nonpaleontologists: Palaios, v. 4, no. 2, p. 127-143, https://doi.org/10.2307/3514601.","productDescription":"17 p.","startPage":"127","endPage":"143","costCenters":[{"id":243,"text":"Eastern Geology and Paleoclimate Science Center","active":true,"usgs":true},{"id":40020,"text":"Florence Bascom Geoscience Center","active":true,"usgs":true}],"links":[{"id":223191,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Maryland, Virginia","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -76.98696044223345,\n 39.13405514877141\n ],\n [\n -76.98696044223345,\n 37.45010665886508\n ],\n [\n -75.80993512276036,\n 37.45010665886508\n ],\n [\n -75.80993512276036,\n 39.13405514877141\n ],\n [\n -76.98696044223345,\n 39.13405514877141\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"4","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b9f77e4b08c986b31e5d4","contributors":{"authors":[{"text":"Edwards, Lucy E. 0000-0003-4075-3317 leedward@usgs.gov","orcid":"https://orcid.org/0000-0003-4075-3317","contributorId":2647,"corporation":false,"usgs":true,"family":"Edwards","given":"Lucy","email":"leedward@usgs.gov","middleInitial":"E.","affiliations":[{"id":40020,"text":"Florence Bascom Geoscience Center","active":true,"usgs":true},{"id":243,"text":"Eastern Geology and Paleoclimate Science Center","active":true,"usgs":true}],"preferred":true,"id":372427,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70209721,"text":"70209721 - 1989 - Source of anomalous magnetization in an area of hydrocarbon potential: Petrologic evidence from the Jurassic Preuss Sandstone, Wyoming-Idaho thrust belt","interactions":[],"lastModifiedDate":"2023-01-25T14:32:13.986839","indexId":"70209721","displayToPublicDate":"1989-02-28T11:07:40","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":701,"text":"American Association of Petroleum Geologists Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"Source of anomalous magnetization in an area of hydrocarbon potential: Petrologic evidence from the Jurassic Preuss Sandstone, Wyoming-Idaho thrust belt","docAbstract":"The Jurassic Preuss Sandstone, which crops out in the central part of the Wyoming-Idaho thrust belt on trend with a hydrocarbon-producing region to the south, has been previously identified as the source of anomalous magnetization in the area. Elsewhere, anomalous magnetization in sedimentary rocks near hydrocarbon accumulations has been attributed to hydrocarbon-engendered magnetic minerals, but magnetization of the Preuss is controlled by detrital magnetite. Evidence of a detrital origin for magnetite includes (1) concentration of magnetite grains along laminations containing other heavy minerals, (2) the presence of exsolved ilmenite, hematite, and spinel in the magnetite grains, and (3) titanium contents typical of igneous-derived magnetite. That detrital magnetite is responsible for the anomalous magnetization in the Preuss is further indicated by the systematic eastward decrease in magnetite abundance corresponding to a similar eastward decrease in magnetic susceptibility and remanent magnetization of the unit.
Petrologic and vitrinite reflectance studies indicate a complex low-temperature (<150°C or 302°F) diagenetic history for the Preuss. Nevertheless, preservation of detrital magnetite, the presence of diagenetically early ferric oxide minerals, and the absence of sulfide minerals all indicate that the Preuss has not experienced sulfidic-reducing conditions common in areas of hydrocarbon seepage. The marine carbon isotopic composition of calcite that cements most Preuss sandstones (^dgr13C values ranging from -2.47 to 1.48^pmil is evidence that carbonate diagenesis also was not influenced by hydrocarbons.
The results of this multidisciplinary study of the Preuss underscore the importance of similar studies when evaluating the sources of aeromagnetic anomalies in areas of hydrocarbon potential.
","language":"English","publisher":"American Association of Petroleum Geologists","doi":"10.1306/703C9B09-1707-11D7-8645000102C1865D","usgsCitation":"Fishman, N.S., Reynolds, R.L., Hudson, M., and Nuccio, V.F., 1989, Source of anomalous magnetization in an area of hydrocarbon potential: Petrologic evidence from the Jurassic Preuss Sandstone, Wyoming-Idaho thrust belt: American Association of Petroleum Geologists Bulletin, v. 73, no. 2, p. 182-194, https://doi.org/10.1306/703C9B09-1707-11D7-8645000102C1865D.","productDescription":"13 p.","startPage":"182","endPage":"194","costCenters":[{"id":318,"text":"Geosciences and Environmental Change Science Center","active":true,"usgs":true}],"links":[{"id":374201,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Idaho, Utah, Wyoming","otherGeospatial":"Wyoming-Idaho thrust belt","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -112.5,\n 40.51379915504413\n ],\n [\n -110.32470703125,\n 40.51379915504413\n ],\n [\n -110.32470703125,\n 44.33956524809713\n ],\n [\n -112.5,\n 44.33956524809713\n ],\n [\n -112.5,\n 40.51379915504413\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"73","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"Fishman, Neil S.","contributorId":106464,"corporation":false,"usgs":true,"family":"Fishman","given":"Neil","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":787673,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Reynolds, Richard L. 0000-0002-4572-2942 rreynolds@usgs.gov","orcid":"https://orcid.org/0000-0002-4572-2942","contributorId":139068,"corporation":false,"usgs":true,"family":"Reynolds","given":"Richard","email":"rreynolds@usgs.gov","middleInitial":"L.","affiliations":[{"id":318,"text":"Geosciences and Environmental Change Science Center","active":true,"usgs":true}],"preferred":true,"id":787674,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hudson, Mark R. 0000-0003-0338-6079 mhudson@usgs.gov","orcid":"https://orcid.org/0000-0003-0338-6079","contributorId":1236,"corporation":false,"usgs":true,"family":"Hudson","given":"Mark R.","email":"mhudson@usgs.gov","affiliations":[{"id":318,"text":"Geosciences and Environmental Change Science Center","active":true,"usgs":true}],"preferred":true,"id":787675,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Nuccio, Vito F. vnuccio@usgs.gov","contributorId":853,"corporation":false,"usgs":true,"family":"Nuccio","given":"Vito","email":"vnuccio@usgs.gov","middleInitial":"F.","affiliations":[],"preferred":true,"id":787676,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70206059,"text":"70206059 - 1989 - The Macon Complex; An ancient accretionary complex in the southern Appalachians","interactions":[{"subject":{"id":70206059,"text":"70206059 - 1989 - The Macon Complex; An ancient accretionary complex in the southern Appalachians","indexId":"70206059","publicationYear":"1989","noYear":false,"title":"The Macon Complex; An ancient accretionary complex in the southern Appalachians"},"predicate":"IS_PART_OF","object":{"id":70206054,"text":"70206054 - 1989 - Melanges Olistostromes of the U.S. Appalachians","indexId":"70206054","publicationYear":"1989","noYear":false,"title":"Melanges Olistostromes of the U.S. Appalachians"},"id":1}],"isPartOf":{"id":70206054,"text":"70206054 - 1989 - Melanges Olistostromes of the U.S. Appalachians","indexId":"70206054","publicationYear":"1989","noYear":false,"title":"Melanges Olistostromes of the U.S. Appalachians"},"lastModifiedDate":"2019-10-18T15:48:27","indexId":"70206059","displayToPublicDate":"1989-01-01T15:39:37","publicationYear":"1989","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"title":"The Macon Complex; An ancient accretionary complex in the southern Appalachians","docAbstract":"The Macon Complex, which extends from eastern Alabama to northern North Carolina, is a late Precambrian–Middle Cambrian accretionary complex comparable in size to the Franciscan Complex of California and Oregon. Much of the complex is tectonic, sedimentary, and metamorphic chaos, properly termed mélange, where well-rounded to angular fragments, blocks, and slabs of contrasting metamorphic grades, different igneous parentages, drastically different sedimentary facies, and different degrees of deformation “float” in highly imbricated and tectonized matrices, the whole having been intruded by Devonian mafic plutons and associated syenites, and by Carboniferous granitic plutons. We have divided the complex into three mélanges that probably reflect different structural regimes within the accretionary wedge: (1) the Juliette mélange, with two tectonostratigraphic lithofacies, the clastic-rich, partly olistostromal Potato Creek facies and the Gladesville facies, rich in mafic and ultramaflc fragments, blocks, and slabs; (2) the Po Biddy mélange, characterized by metamorphosed manganiferous sediments, metavolcaniclastic rocks, graphitic schists, and locally by metamorphosed thinly bedded pyritiferous limestones, and a wide variety of mineral deposits; and (3) the Falls Lake mélange, which is quite similar to the Juliette mélange and probably represents the same tectonostratigraphic horizon in the accretionary prism. The matrices of the mélanges contain a wide variety of metaigneous and metasedimentary exotic clasts, including mafic and ultramaflc rocks. The Macon Complex is structurally overlain by the late Precambrian–Middle Cambrian Little River Complex, made up of thick piles of mostly felsic calc-alkaline metavolcanic rocks, and lesser amounts of metaplutonic rocks, that originated in a continental-margin volcanic arc (Little River arc). Trilobites from near the top of one of the youngest sections are restricted to the upper two-thirds of the Middle Cambrian and are characteristic of the Atlantic faunal province. The Little River Complex is overlain, beneath the Atlantic Coastal Plain, by the African cratonic Northern Florida platform sequence; the Macon and Little River complexes and the Northern Florida platform sequence make up the Little River thrust stack. The magmas of the Devonian plutons that have intruded the Macon Complex probably formed when the Little River stack was thrust upon the underlying Georgiabama thrust stack, which was itself still being thrust toward the North American craton. The Macon Complex is interpreted to have formed between a trench and the Little River island arc at the oceanward edge of what was either a microcontinent off the African continent or the core of the present African continent. Many mafic and all ultramaflc bodies in the mélange are probably pieces of Iapetus Ocean crust and mantle offscraped from the downgoing slab and imbricated into the accretionary wedge. Rocks of the Macon Complex have previously been assigned to the “Charlotte,” “Kiokee,” “Kings Mountain,” and “Lowndesville” belts and to parts of the “Uchee,” “Raleigh,” “Pine Mountain,” and “Inner Piedmont” “belts.”
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Mélanges Olistostromes of the U.S. Appalachians","largerWorkSubtype":{"id":15,"text":"Monograph"},"language":"English","publisher":"Geological Society of America","doi":"10.1130/SPE228-p229","usgsCitation":"Higgins, M.W., Crawford, R., Atkins, R.L., and Crawford, T.J., 1989, The Macon Complex; An ancient accretionary complex in the southern Appalachians, chap. of Mélanges Olistostromes of the U.S. Appalachians, p. 229-246, https://doi.org/10.1130/SPE228-p229.","productDescription":"18 p.","startPage":"229","endPage":"246","costCenters":[],"links":[{"id":368428,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Alabama, Georgia, North Carolina, South Carolina","otherGeospatial":"Macon Complex","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -85.40771484375,\n 31.3348710339506\n ],\n [\n -79.332275390625,\n 34.867904962568716\n ],\n [\n -78.01391601562499,\n 36.465471886798134\n ],\n [\n -80.57373046875,\n 36.518465989675875\n ],\n [\n -84.92431640625,\n 33.22030778968541\n ],\n [\n -85.40771484375,\n 32.13840869677249\n ],\n [\n -85.40771484375,\n 31.3348710339506\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationDate":"1989-01-01","publicationStatus":"PW","contributors":{"authors":[{"text":"Higgins, Michael W.","contributorId":12459,"corporation":false,"usgs":true,"family":"Higgins","given":"Michael","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":773441,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Crawford, Ralph","contributorId":219872,"corporation":false,"usgs":false,"family":"Crawford","given":"Ralph","email":"","affiliations":[],"preferred":false,"id":773442,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Atkins, R. L.","contributorId":77540,"corporation":false,"usgs":true,"family":"Atkins","given":"R.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":773443,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Crawford, Thomas J.","contributorId":73640,"corporation":false,"usgs":true,"family":"Crawford","given":"Thomas","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":773444,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70209581,"text":"70209581 - 1989 - Zircon geochronology of Precambrian rocks in southeastern Wyoming and northern Colorado","interactions":[],"lastModifiedDate":"2020-04-14T15:58:00.929285","indexId":"70209581","displayToPublicDate":"1989-01-01T10:50:33","publicationYear":"1989","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"title":"Zircon geochronology of Precambrian rocks in southeastern Wyoming and northern Colorado","docAbstract":"Archean gneisses and Early Proterozoic metasedimentary rocks of the Wyoming Province are separated from Proterozoic eugeoclinal metamorphic rocks by a major east-west–trending shear zone called the Cheyenne belt. U-Pb zircon ages of Archean tonalites north of the Cheyenne belt denote an intrusive event at 2,700 Ma. Detrital zircons from Proterozoic metasedimentary rocks north of the Cheyenne belt define an apparent age of 2,450 Ma for the source rock, similar to an age of 2,430 Ma obtained for a local granite. A metagabbro plug, which intruded the metasedimentary rocks about 2,100 Ma, constrains their deposition within this 350 m.y. period. Ages for key units just south of the Cheyenne belt in Wyoming delineate at least three magmatic events at 1,780; 1,750; and 1,625 Ma. Ages for large plutons in the northern Colorado area define pulses of granodioritic to granitic intrusions at approximately 1,720 and 1,670 Ma.
A U-Pb zircon age of 1,792 ± 15 Ma for a Proterozoic metavolcanic rock in the Sierra Madre is greater than ages reported for other Proterozoic metavolcanic rocks in the U.S. Rockies. However, ages for Proterozoic plutons in southeastern Wyoming are similar to other ages for plutonism and volcanism for rocks exposed in the central Colorado Rockies and are coeval with suturing of Proterozoic crust with the Archean Wyoming Province along the Cheyenne belt. Although at present the accretionary history for these Early Proterozoic rocks is not well understood, it is evident that there exists a progressive decrease in age for volcanism as well as plutonism from north to south.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Proterozoic geology of the Southern Rocky Mountains","largerWorkSubtype":{"id":15,"text":"Monograph"},"language":"English","publisher":"Geological Society of America","doi":"10.1130/SPE235-p13","usgsCitation":"Premo, W.R., and Van Schmus, W.R., 1989, Zircon geochronology of Precambrian rocks in southeastern Wyoming and northern Colorado, chap. of Proterozoic geology of the Southern Rocky Mountains, v. 235, p. 13-32, https://doi.org/10.1130/SPE235-p13.","productDescription":"20 p.","startPage":"13","endPage":"32","costCenters":[{"id":318,"text":"Geosciences and Environmental Change Science Center","active":true,"usgs":true}],"links":[{"id":373967,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Colorado, Wyoming","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -106.358642578125,\n 40.18307014852534\n ],\n [\n -104.3865966796875,\n 40.18307014852534\n ],\n [\n -104.3865966796875,\n 41.705728515237524\n ],\n [\n -106.358642578125,\n 41.705728515237524\n ],\n [\n -106.358642578125,\n 40.18307014852534\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"235","noUsgsAuthors":false,"publicationDate":"1989-01-01","publicationStatus":"PW","contributors":{"authors":[{"text":"Premo, Wayne R. 0000-0001-9904-4801 wpremo@usgs.gov","orcid":"https://orcid.org/0000-0001-9904-4801","contributorId":1697,"corporation":false,"usgs":true,"family":"Premo","given":"Wayne","email":"wpremo@usgs.gov","middleInitial":"R.","affiliations":[],"preferred":true,"id":787006,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Van Schmus, W. R.","contributorId":83114,"corporation":false,"usgs":true,"family":"Van Schmus","given":"W.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":787007,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70210208,"text":"70210208 - 1989 - Regional crustal structure and tectonics of the Pacific Coastal States: California, Oregon, and Washington","interactions":[],"lastModifiedDate":"2020-05-20T14:58:55.848594","indexId":"70210208","displayToPublicDate":"1989-01-01T09:53:53","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1726,"text":"GSA Memoirs","active":true,"publicationSubtype":{"id":10}},"title":"Regional crustal structure and tectonics of the Pacific Coastal States: California, Oregon, and Washington","docAbstract":"The Pacific Coastal States form a complex geologic environment in which the crust and lithosphere have been continuously reworked. We divide the region tectonically into the southern transform regime of the San Andreas fault and the northern subduction regime, and summarize the geophysical framework with contour maps of crustal thickness, lithospheric and seismicity cross sections, and results from site-specific geophysical studies. The uniformity of crustal thickness (30 ± 2 km) in southern California is remarkable, and appears to be primarily the result of crustal extension in the Mojave Desert and ductile shear of the lower crust along the plate transform boundary. Southern California seismicity defines a broad zone of deformation that extends from the Borderland to the Mojave Desert (about 300 km). The geophysical framework of central and northern California records magmatism and accretion associated with the Mesozoic and Cenozoic subduction, late Cenozoic transform faulting, and in the Basin and Range to the east, extension. The crust thickens from about 20 km at the coast to as much as 55 km in the Sierra Nevada, and thins to about 30 km in the Basin and Range. Cross sections of the crust show that seismic velocities and densities vary significantly over short distances perpendicular to the coast, reflecting processes that include the accretion of oceanic sediments and igneous crust, and significant lateral motion of crustal blocks. Maximum hypocentral depths in central California become deeper as the crust thickens to the west, but seismicity is low beneath the Great Valley and Sierra Nevada, which together appear to form a relatively undeforming block. The lower crust of the Pacific Coastal States has a high average seismic velocity (6.7 km/sec or greater), which probably is the product of tectonic underplating of oceanic crust and/or magmatic underplating by a basaltic melt.
","language":"English","publisher":"Geological Society of America","doi":"10.1130/MEM172-p129","usgsCitation":"Mooney, W.D., and Weaver, C.S., 1989, Regional crustal structure and tectonics of the Pacific Coastal States: California, Oregon, and Washington: GSA Memoirs, v. 172, p. 129-161, https://doi.org/10.1130/MEM172-p129.","productDescription":"33 p.","startPage":"129","endPage":"161","costCenters":[{"id":237,"text":"Earthquake Science Center","active":true,"usgs":true}],"links":[{"id":374963,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California, Oregon, 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\"}}]}","volume":"172","noUsgsAuthors":false,"publicationDate":"1989-01-01","publicationStatus":"PW","contributors":{"authors":[{"text":"Mooney, Walter D. 0000-0002-5310-3631 mooney@usgs.gov","orcid":"https://orcid.org/0000-0002-5310-3631","contributorId":3194,"corporation":false,"usgs":true,"family":"Mooney","given":"Walter","email":"mooney@usgs.gov","middleInitial":"D.","affiliations":[{"id":237,"text":"Earthquake Science Center","active":true,"usgs":true}],"preferred":true,"id":789535,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Weaver, Craig S. craig@usgs.gov","contributorId":2690,"corporation":false,"usgs":true,"family":"Weaver","given":"Craig","email":"craig@usgs.gov","middleInitial":"S.","affiliations":[{"id":237,"text":"Earthquake Science Center","active":true,"usgs":true}],"preferred":true,"id":789536,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":26496,"text":"wri884219 - 1989 - An investigation of shallow ground-water quality near East Fork Poplar Creek, Oak Ridge, Tennessee","interactions":[],"lastModifiedDate":"2023-03-21T20:18:11.557459","indexId":"wri884219","displayToPublicDate":"1989-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"88-4219","title":"An investigation of shallow ground-water quality near East Fork Poplar Creek, Oak Ridge, Tennessee","docAbstract":"Alluvial soils of the flood plain of East Fork Poplar Creek in Oak Ridge, Tennessee, are contaminated with mercury and other metals, organic compounds, and radio-nuclides originating from the Y-12 Plant, a nuclear-processing facility located within the U.S. Department of Energy 's Oak Ridge Reservation. Observation wells were installed in the shallow aquifer of the flood plain, and water quality samples were collected to determine if contaminants are present in the shallow groundwater. Groundwater in the shallow aquifer occurs under water-table conditions. Recharge is primarily from precipitation and discharge is to East Fork Poplar Creek. Groundwater levels fluctuate seasonally in response to variations in recharge and evapotranspiration. During extremely dry periods, the water table drops below the base of the shallow aquifer in some flood-plain areas. Contaminants found in water samples from several of the wells in concentrations which equaled or exceeded drinking-water standards established by the U.S. Environmental Protection Agency are antimony, chromium, lead, mercury, selenium, phenols, and strontium-90. Total and dissolved uranium concentrations exceeded the analytical detection limit in nearly 70% of the wells in the flood plain. The results of water quality determinations demonstrate that elevated concentrations of most trace metals (and possibly organic compounds and radionuclides) were caused by contaminated sediments in the samples. The presence of contaminated sediment in samples is suspected to be the result of borehole contamination during well installation.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/wri884219","usgsCitation":"Carmichael, J.K., 1989, An investigation of shallow ground-water quality near East Fork Poplar Creek, Oak Ridge, Tennessee: U.S. Geological Survey Water-Resources Investigations Report 88-4219, v, 49 p., https://doi.org/10.3133/wri884219.","productDescription":"v, 49 p.","costCenters":[],"links":[{"id":123597,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/wri_88_4219.jpg"},{"id":414497,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_47116.htm","linkFileType":{"id":5,"text":"html"}},{"id":2087,"rank":2,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.water.usgs.gov/wri88-4219","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"Tennessee","city":"Oak Ridge","otherGeospatial":"East Fork Poplar Creek","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -84.3,\n 36.0181\n ],\n [\n -84.3,\n 35.9806\n ],\n [\n -84.2444,\n 35.9806\n ],\n [\n -84.2444,\n 36.0181\n ],\n [\n -84.3,\n 36.0181\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4ad6e4b07f02db684245","contributors":{"authors":[{"text":"Carmichael, J. K.","contributorId":90276,"corporation":false,"usgs":true,"family":"Carmichael","given":"J.","email":"","middleInitial":"K.","affiliations":[],"preferred":false,"id":196495,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70015014,"text":"70015014 - 1989 - A reinterpretation of the δDH2O of inclusion fluids in contemporaneous quartz and sphalerite, Creede mining district, Colorodo: a generic problem for shallow orebodies?","interactions":[],"lastModifiedDate":"2018-10-22T10:41:29","indexId":"70015014","displayToPublicDate":"1989-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1472,"text":"Economic Geology","active":true,"publicationSubtype":{"id":10}},"title":"A reinterpretation of the δDH2O of inclusion fluids in contemporaneous quartz and sphalerite, Creede mining district, Colorodo: a generic problem for shallow orebodies?","docAbstract":"Water extracted from fluid inclusions in quartz from shallow epithermal ore deposits often has a hydrogen isotope composition (δD) different from that of water extracted from inclusions in associated minerals. This difference is usually attributed to the involvement of primary fluids from multiple sources. Isotopic and homogenization and freezing temperature determinations on fluid inclusions from contemporaneous quartz and sphalerite from the epithermal, silver and base metal orebodies of the OH vein, Creede district, Colorado, suggest an alternative explanation. In near-surface deposits, differences between δDH2O of inclusion fluids in ore minerals and quartz may result, instead, from contamination during extraction of the fluids contained in primary inclusions by shallow ground water trapped in pseudosecondary inclusions in quartz.
\nQuartz from the OH vein contains two principal petrographically distinct populations of fluid inclusions: primary and pseudosecondary. The primary inclusions have salinities ranging from 5 to 10 equiv wt percent NaCl, and the salinities of pseudosecondary inclusions cluster between 0 and 1 percent. Primary inclusions in quartz from one locality have a measured δDH2O value of -69 per mil, while pseudosecondary inclusions at the same locality have a δDH2O value of -102 per mil. Both salinity and isotopic values for primary inclusions in quartz are similar to those for primary inclusions in contemporaneous sphalerite. Homogenization temperatures for primary and pseudosecondary inclusions in quartz range from 191° to 280° C and from 199° to 278° C, respectively. The δDH2O value measured on fluid inclusions from bulk crystals ranges between -97 and -85 per mil and represents a mixture of fluids from both primary and pseudosecondary inclusions.
\nWe interpret the data to indicate that one or more episodes of abrupt incursion of cooler, overlying ground water into the ore zone caused thermal cracking of the quartz crystals during the time interval of mineralization. Subsequent healing of the fractures trapped heated, low-salinity ground water in pseudosecondary inclusions. The abrupt incursions of overlying ground water are speculated to have resulted from either collapse of a transient vapor-dominated region of the ore zone, or catastrophic venting of the system through hydrothermal eruption(s).
\nThe unusually high contrast between the salinities of the ore-depositing fluids and the ground water overlying the ore zone allowed recognition of this phenomenon at Creede. It is likely, however, that Creede is not unique. Similar phenomena may be common in shallow ore zones where rapid fluctuation of an interface between a deep, high-temperature thermal plume and an overlying, cooler ground water may be expected to occur. Careful study of the origins of fluid inclusions, particularly in quartz, is essential to characterize the primary ore fluids and to assess the role of ground water in the hydrology of shallow ore deposits.
","language":"English","publisher":"Society of Economic Geologists","doi":"10.2113/gsecongeo.84.7.1966","issn":"03610128","usgsCitation":"Foley, N.K., Bethke, P., and Rye, R.O., 1989, A reinterpretation of the δDH2O of inclusion fluids in contemporaneous quartz and sphalerite, Creede mining district, Colorodo: a generic problem for shallow orebodies?: Economic Geology, v. 84, no. 7, p. 1966-1977, https://doi.org/10.2113/gsecongeo.84.7.1966.","productDescription":"12 p.","startPage":"1966","endPage":"1977","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":245,"text":"Eastern Mineral and Environmental Resources Science Center","active":true,"usgs":true}],"links":[{"id":223576,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Colorado","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -108.5943603515625,\n 37.00693943418586\n ],\n [\n -108.5943603515625,\n 38.805470223177466\n ],\n [\n -106.116943359375,\n 38.805470223177466\n ],\n [\n -106.116943359375,\n 37.00693943418586\n ],\n [\n -108.5943603515625,\n 37.00693943418586\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"84","issue":"7","noUsgsAuthors":false,"publicationDate":"1989-11-01","publicationStatus":"PW","scienceBaseUri":"5059e545e4b0c8380cd46c55","contributors":{"authors":[{"text":"Foley, Nora K. 0000-0003-0124-3509 nfoley@usgs.gov","orcid":"https://orcid.org/0000-0003-0124-3509","contributorId":4010,"corporation":false,"usgs":true,"family":"Foley","given":"Nora","email":"nfoley@usgs.gov","middleInitial":"K.","affiliations":[{"id":245,"text":"Eastern Mineral and Environmental Resources Science Center","active":true,"usgs":true}],"preferred":true,"id":369856,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bethke, Philip M.","contributorId":52829,"corporation":false,"usgs":true,"family":"Bethke","given":"Philip M.","affiliations":[],"preferred":false,"id":369857,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Rye, Robert O. rrye@usgs.gov","contributorId":1486,"corporation":false,"usgs":true,"family":"Rye","given":"Robert","email":"rrye@usgs.gov","middleInitial":"O.","affiliations":[{"id":211,"text":"Crustal Geophysics and Geochemistry Science Center","active":true,"usgs":true}],"preferred":true,"id":369858,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70015518,"text":"70015518 - 1989 - Remarkable isotopic and trace element trends in potassic through sodic Cretaceous plutons of the Yukon-Koyukuk Basin, Alaska, and the nature of the lithosphere beneath the Koyukuk terrane","interactions":[],"lastModifiedDate":"2018-10-22T10:45:45","indexId":"70015518","displayToPublicDate":"1989-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2314,"text":"Journal of Geophysical Research B: Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"Remarkable isotopic and trace element trends in potassic through sodic Cretaceous plutons of the Yukon-Koyukuk Basin, Alaska, and the nature of the lithosphere beneath the Koyukuk terrane","docAbstract":"During the period from 110 to 80 m.y. ago, a 450-km-long magmatic belt was active along the northern margin of Yukon-Koyukuk basin and on eastern Seward Peninsula. The plutons intruded Upper Jurassic(?) and Lower Cretaceous volcanic arc rocks and Cretaceous sedimentary rocks in Yukon-Koyukuk basin and Proterozoic and lower Paleozoic continental rocks in Seward Peninsula. Within Yukon-Koyukuk basin, the plutons vary in composition from calc-alkalic plutons on the east to potassic and ultrapotassic alkalic plutons on the west. Plutons within Yukon-Koyukuk basin were analyzed for trace element and isotopic compositions in order to discern their origin and the nature of the underling lithosphere. Farthest to the east, the calc-alkalic rocks of Indian Mountain pluton are largely tonalite and sodic granodiorite, and have low Rb (average 82 ppm), high Sr (>600 ppm), high chondrite-normalized (cn) Ce/Yb (16–37), low δ18O (+6.5 to +7.1), low initial 87Sr/86Sr (SIR) (0.704), and high initial 143Nd/144Nd (NIR) (0.5126). These rocks resemble those modelled elsewhere as partial melts and subsequent fractionates of basaltic or gabbroic metaigneous rocks, and may be products of melting in the deeper parts of the Late Jurassic(?) and Early Cretaceous volcanic arc. Farthest to the west, the two ultrapotassic bodies of Selawik and Inland Lake are high in Cs (up to 93 ppm), Rb (up to 997 ppm), Sr, Ba, Th, and light rare earth elements, have high (Ce/Yb)cn (30, 27), moderate to low δ18O (+8.4, +6.9), high SIR (0.712, 0.710), and moderate NIR (0.5121–0.5122). These rocks resemble rocks of Australia and elsewhere that were modelled as melts of continental mantle that had been previously enriched in large cations. This mantle may be Paleozoic or older. The farthest west alkalic pluton of Selawik Hills is largely monzonite, quartz monzonite, and granite; has moderate Rb (average 284 ppm), high Sr (>600 ppm), high (Ce/Yb)cn (15–25), moderate δ18O (+8.3 to +8.6), high SIR (0.708–0.712), and moderate NIR (0.5121–0.5122). These rocks may be the product of interaction of magma derived from old continental mantle and magma derived from old continental crust. Plutons between eastern and western extremes show completely gradational variations in the concentration of K and Rb and in the isotopic compositions of Sr, Nd, and O. These plutons probably originated either by melting in a mixed source composed of a Paleozoic or older continental section (mantle + crust) overlain by Mesozoic mafic arc rocks, or by mixing of ultrapotassic to potassic magmas from continental sources (mantle + crust), and tonalitic magmas from arc sources. We infer from these results that the northwest portion of Yukon-Koyukuk basin is underlain by a substantial continental basement of Paleozoic or greater age. This basement probably thins out to the east. There is no geochemical evidence for continental basement east of about longitude 157°, or along a belt of at least 50 km width flanking Ruby Geanticline as far to the southwest as about longitude 161°. These areas are probably underlain by oceanic and Mesozoic arc rocks.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB094iB11p15957","issn":"01480227","usgsCitation":"Arth, J.G., Criss, R.E., Zmuda, C.C., Foley, N.K., Patton, W.W., and Miller, T.P., 1989, Remarkable isotopic and trace element trends in potassic through sodic Cretaceous plutons of the Yukon-Koyukuk Basin, Alaska, and the nature of the lithosphere beneath the Koyukuk terrane: Journal of Geophysical Research B: Solid Earth, v. 94, no. B11, p. 15957-15968, https://doi.org/10.1029/JB094iB11p15957.","productDescription":"12 p.","startPage":"15957","endPage":"15968","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":245,"text":"Eastern Mineral and Environmental Resources Science Center","active":true,"usgs":true}],"links":[{"id":498891,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/jb094ib11p15957","text":"Publisher Index Page"},{"id":223605,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Alaska","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -163,\n 64\n ],\n [\n -163,\n 68\n ],\n [\n -152,\n 68\n ],\n [\n -152,\n 64\n ],\n [\n -163,\n 64\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"94","issue":"B11","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"505aa6c6e4b0c8380cd85042","contributors":{"authors":[{"text":"Arth, Joseph G.","contributorId":104546,"corporation":false,"usgs":true,"family":"Arth","given":"Joseph","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":371138,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Criss, Robert E.","contributorId":39447,"corporation":false,"usgs":true,"family":"Criss","given":"Robert","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":371133,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Zmuda, Clara C.","contributorId":91991,"corporation":false,"usgs":true,"family":"Zmuda","given":"Clara","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":371137,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Foley, Nora K. 0000-0003-0124-3509 nfoley@usgs.gov","orcid":"https://orcid.org/0000-0003-0124-3509","contributorId":4010,"corporation":false,"usgs":true,"family":"Foley","given":"Nora","email":"nfoley@usgs.gov","middleInitial":"K.","affiliations":[{"id":245,"text":"Eastern Mineral and Environmental Resources Science Center","active":true,"usgs":true}],"preferred":true,"id":371134,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Patton, W. W. Jr.","contributorId":11231,"corporation":false,"usgs":true,"family":"Patton","given":"W.","suffix":"Jr.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":371135,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Miller, T. P.","contributorId":49345,"corporation":false,"usgs":true,"family":"Miller","given":"T.","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":371136,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70015614,"text":"70015614 - 1989 - Significance of new potassium-argon ages from the Goldens Ranch and Moroni Formations, Sanpete-Sevier Valley area, central Utah","interactions":[],"lastModifiedDate":"2023-12-27T12:35:18.473736","indexId":"70015614","displayToPublicDate":"1989-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1786,"text":"Geological Society of America Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"Significance of new potassium-argon ages from the Goldens Ranch and Moroni Formations, Sanpete-Sevier Valley area, central Utah","docAbstract":"Exposures of volcanic-sedimentary strata are widely distributed within central Utah. We believe that these volcanic and stratified sedimentary rocks, known by different formational names in different parts of this region, are, in fact, segments of one and the same suite of rocks that formed during the early and middle Tertiary.
The volcanic-sedimentary complex is exposed on both sides of a north-trending lowland formed by the collinear Juab and Sevier Valleys. West of the lowland, the complex has been named the \"Goldens Ranch Formation\" east of the lowland, it has been called the \"Moroni Formation.\"; Both formations are stratigraphically alike in that each consists of a lower unit composed predominantly of water-laid, variably cemented sediments and sedimentary rocks with some tuff beds near the base, and an upper unit of intermediate-composition volcanic rocks, chiefly ash-flow tuffs, and volcanic breccias. Both formations contain abundant exotic clasts of andesite, tan and purple quartzite, and dark blue limestone and dolomite. Both formations are folded and faulted along with the underlying sedimentary units.
Potassium-argon ages indicate that both the Goldens Ranch and Moroni Formations formed during the late Eocene to middle Oligocene. The geochronology and stratigraphic relations are strong evidence that the Goldens Ranch and Moroni Formations are correlative, and that they are one and the same depositional unit.
During the latest Oligocene-earliest Miocene, minor monzonitic bodies intruded sedimentary units in the area.
The new K-Ar data bear on the matter of the origin of the complex structural deformation in central Utah. Different workers have attributed the singular deformation either to recurrent episodes of compression stemming from the Sevier orogeny, or to repeated episodes of salt diapirism. We recognize two sequences of repeated deformation: one that occurred prior to deposition and consolidation of the Goldens Ranch and Moroni Formations, and a second that occurred after these formations were emplaced, in essence, after early Oligocene time. The Sevier orogeny ended in Paleocene time; thus, the compression and thrusting stemming from the Sevier orogeny could be responsible for the structural complexity that marks pre-Paleocene units. These same orogenic forces do not seem to be viable explanations for the broad flexures and monoclinal downwarps that mark the Goldens Ranch, Moroni, and younger formations. In our view, multiple episodes of salt diapirism more reasonably explain the structural complexity in central Utah.
","language":"English","publisher":"Geological Society of America","doi":"10.1130/0016-7606(1989)101<0534:SONPAA>2.3.CO;2","usgsCitation":"Witkind, I.J., and Marvin, R.F., 1989, Significance of new potassium-argon ages from the Goldens Ranch and Moroni Formations, Sanpete-Sevier Valley area, central Utah: Geological Society of America Bulletin, v. 101, no. 4, p. 534-548, https://doi.org/10.1130/0016-7606(1989)101<0534:SONPAA>2.3.CO;2.","productDescription":"15 p.","startPage":"534","endPage":"548","numberOfPages":"15","costCenters":[],"links":[{"id":224433,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Utah","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -112.40554338984188,\n 39.776483822588716\n ],\n [\n -112.40554338984188,\n 38.91841705321613\n ],\n [\n -111.26296526484207,\n 38.91841705321613\n ],\n [\n -111.26296526484207,\n 39.776483822588716\n ],\n [\n -112.40554338984188,\n 39.776483822588716\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"101","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8f1be4b08c986b318d24","contributors":{"authors":[{"text":"Witkind, I. J.","contributorId":54221,"corporation":false,"usgs":true,"family":"Witkind","given":"I.","middleInitial":"J.","affiliations":[],"preferred":false,"id":371370,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Marvin, R. F.","contributorId":60597,"corporation":false,"usgs":true,"family":"Marvin","given":"R.","middleInitial":"F.","affiliations":[],"preferred":false,"id":371371,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70014955,"text":"70014955 - 1989 - Isotopic and trace element variations in the Ruby Batholith, Alaska, and the nature of the deep crust beneath the Ruby and Angayucham Terranes","interactions":[],"lastModifiedDate":"2018-10-22T10:43:02","indexId":"70014955","displayToPublicDate":"1989-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2314,"text":"Journal of Geophysical Research B: Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"Isotopic and trace element variations in the Ruby Batholith, Alaska, and the nature of the deep crust beneath the Ruby and Angayucham Terranes","docAbstract":"Thirty-six samples from plutons of the Ruby batholith of central Alaska were collected and analyzed for 22 trace elements, and many were analyzed for the isotopic compositions of Sr, Nd, O, and Pb in order to delimit the processes that produced the diversity of granodioritic to granitic compositions, to deduce the nature of the source of magmas at about 110 Ma, and to characterize the deep crust beneath the Ruby and Angayucham terranes. Plutons of the batholith show a substantial range in initial 87Sr/86Sr (SIR) of 0.7055–0.7235 and a general decrease from southwest to northeast. Initial 143Nd/144Nd (NIR) have a range of 0.51150–0.51232 and generally increase from southwest to northeast. The δ18O values for most whole rocks have a range of +8.4 to +11.8 and an average of +10.3‰. Rb, Cs, U, and Th show large ranges of concentration, generally increase as SiO2 increases, and are higher in southwest than in northeast plutons. Sr, Ba, Zr, Hf, Ta, Sc, Cr, Co, and Zr show large ranges of concentration and generally decrease as SiO2 increases. Rare earth elements (REE) show fractionated patterns and negative Eu anomalies. REE concentrations and anomalies are larger in the southwest than in the northeast plutons. Uniformity of SIR and NIR in Sithylemenkat and Jim River plutons suggests a strong role for fractional crystallization or melting of uniform magma sources at depth. Isotopic variability in Melozitna, Ray Mountains, Hot Springs, and Kanuti plutons suggests complex magmatic processes such as magma mixing and assimilation, probably combined with fractional crystallization, or melting of a complex source at depth. The large variations in SIR and NIR in the batholith require a variation in source materials at depth. The southwestern plutons probably had dominantly siliceous sources composed of metamorphosed Proterozoic and Paleozoic upper crustal rocks. The northeastern plutons probably had Paleozoic sources that were mixtures of siliceous and intermediate to mafic crustal rocks. The inferred sources could well have been the higher-metamorphic-grade lithologic equivalents of the exposed Proterozoic(?) to Paleozoic schists, orthogneisses, and metavolcanic rocks of Ruby terrane, the silicic portions of which are quite radiogenic. The deeper crustal sources that gave rise to most of the batholithic magmas are inferred to be similar under both the Ruby metamorphic terrane and the Angayucham ophiolitic terrane.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB094iB11p15941","issn":"01480227","usgsCitation":"Arth, J.G., Zmuda, C.C., Foley, N.K., Criss, R.E., Patton, W.W., and Miller, T.P., 1989, Isotopic and trace element variations in the Ruby Batholith, Alaska, and the nature of the deep crust beneath the Ruby and Angayucham Terranes: Journal of Geophysical Research B: Solid Earth, v. 94, no. B11, p. 15941-15955, https://doi.org/10.1029/JB094iB11p15941.","productDescription":"15 p.","startPage":"15941","endPage":"15955","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":245,"text":"Eastern Mineral and Environmental Resources Science Center","active":true,"usgs":true}],"links":[{"id":224447,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Alaska","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -155.9619140625,\n 67.99110834539987\n ],\n [\n -148.0078125,\n 68.00757101804004\n ],\n [\n -146.95312499999997,\n 66.10716955858042\n ],\n [\n -150.97412109375,\n 64.00486735371551\n ],\n [\n -156.02783203124997,\n 64.01449619484472\n ],\n [\n -155.9619140625,\n 67.99110834539987\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"94","issue":"B11","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"505a3f9ae4b0c8380cd64652","contributors":{"authors":[{"text":"Arth, Joseph G.","contributorId":104546,"corporation":false,"usgs":true,"family":"Arth","given":"Joseph","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":369703,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Zmuda, Clara C.","contributorId":91991,"corporation":false,"usgs":true,"family":"Zmuda","given":"Clara","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":369702,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Foley, Nora K. 0000-0003-0124-3509 nfoley@usgs.gov","orcid":"https://orcid.org/0000-0003-0124-3509","contributorId":4010,"corporation":false,"usgs":true,"family":"Foley","given":"Nora","email":"nfoley@usgs.gov","middleInitial":"K.","affiliations":[{"id":245,"text":"Eastern Mineral and Environmental Resources Science Center","active":true,"usgs":true}],"preferred":true,"id":369699,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Criss, Robert E.","contributorId":39447,"corporation":false,"usgs":true,"family":"Criss","given":"Robert","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":369698,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Patton, W. W. Jr.","contributorId":11231,"corporation":false,"usgs":true,"family":"Patton","given":"W.","suffix":"Jr.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":369700,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Miller, T. P.","contributorId":49345,"corporation":false,"usgs":true,"family":"Miller","given":"T.","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":369701,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70137840,"text":"70137840 - 1989 - Impacts of exploratory drilling for oil and gas on the benthic environment of Georges Bank","interactions":[],"lastModifiedDate":"2017-11-05T11:46:18","indexId":"70137840","displayToPublicDate":"1989-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2664,"text":"Marine Environmental Research","active":true,"publicationSubtype":{"id":10}},"title":"Impacts of exploratory drilling for oil and gas on the benthic environment of Georges Bank","docAbstract":"A 3-year monitoring program was performed to assess the impacts of exploratory drilling for oil and gas on the benthic environment of Georges Bank, an important commercial fishery region in the North Atlantic east of Massachusetts, USA. Surficial sediments were sampled for chemical and benthic infaunal analysis and bottom still photographs were taken to document bottom microtopography and epifauna at 46 stations during 12 field surveys. The surveys were performed quarterly from just before drilling began, during drilling, and for nearly 2 years after completion of drilling. Two of the eight drilling sites were selected for monitoring. Twenty-nine stations were positioned in a tight radial array around a drilling site in 80 m of water. A second group of three stations was positioned near another drilling site in 140 m of water. The remaining stations covered a broad expanse of the Bank and adjacent suspected sites of deposition of fine-grained sediments.\\
\n\n
Of the 12 elements analyzed in bulk sediments, only barium increased in concentration during the period when drilling was taking place (July 1981 to September 1982). The concentration of barium in surficial sediment increased 4·7-fold from 28 ppm before drilling to 131·7 ppm after drilling at the station closest to the drilling site in 80 m of water and 5·9-fold from 32 ppm before drilling to 172 ppm after drilling at the station closest to the drilling site in 140 m of water. The concentrations of both barium and chromium increased in the fine (silt/clay) fraction (usually less than 5% by weight of sediment from most stations) of sediments from several stations around one or both rig sites monitored during the period of drilling. Elevated concentrations of chromium (about two-fold) occurred only in sediments near the drilling site in 140 m of water. Statistically significant increases in the concentration of barium in the fine fraction to sediment were detected approximately 65 km west (downcurrent) and 35 km east of the drilling site in 80 m of water after drilling was completed.
\n\n
The benthic fauna were abundant and diverse throughout the study area. At most stations, the dominant species remained nearly the same from one season to another over the 3 years of sampling. Polychaetes were the most abundant, followed by crustaceans. The number of individuals of some species, particularly the amphipods Erichthonius fasciatus and Unciola inermis, showed large seasonal variations.
\n\n
Cluster analysis revealed a strong relationship between community structure and both sediment type and water depth. Little seasonal variation was detected, but some interannual differences were revealed by cluster analysis and correspondence analysis. The replicates from a station always resembled each other more than they resembled any replicates from other stations. In addition, the combined replicates from a station always clustered with samples from that station taken on other cruises. This excellent replication and uniformity of the benthic infaunal community at a station over time made it possible to detect very subtle changes in community parameters that might be related to discharges of drilling fluid and drill cuttings. Nevertheless, no changes were detected in benthic communities of Georges Bank that could be attributed to drilling activities.
","language":"English","publisher":"Elsevier","doi":"10.1016/0141-1136(89)90002-0","usgsCitation":"Neff, J.M., Bothner, M., Maciolek, N.J., and Grassle, J.F., 1989, Impacts of exploratory drilling for oil and gas on the benthic environment of Georges Bank: Marine Environmental Research, v. 27, no. 2, p. 77-114, https://doi.org/10.1016/0141-1136(89)90002-0.","productDescription":"38 p.","startPage":"77","endPage":"114","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":186,"text":"Coastal and Marine Geology Program","active":true,"usgs":true}],"links":[{"id":297172,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Massachusetts","otherGeospatial":"Georges Bank","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -73.23486328124999,\n 42.827638636242284\n ],\n [\n -69.6533203125,\n 42.85985981506279\n ],\n [\n -69.98291015625,\n 41.57436130598913\n ],\n [\n -73.54248046875,\n 42.08191667830631\n ],\n [\n -73.23486328124999,\n 42.827638636242284\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"27","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"54dd2bd0e4b08de9379b34f1","contributors":{"authors":[{"text":"Neff, J. M.","contributorId":138626,"corporation":false,"usgs":false,"family":"Neff","given":"J.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":538149,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bothner, Michael H. mbothner@usgs.gov","contributorId":139855,"corporation":false,"usgs":true,"family":"Bothner","given":"Michael H.","email":"mbothner@usgs.gov","affiliations":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":false,"id":538150,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Maciolek, N. J.","contributorId":138627,"corporation":false,"usgs":false,"family":"Maciolek","given":"N.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":538151,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Grassle, J. F.","contributorId":8621,"corporation":false,"usgs":false,"family":"Grassle","given":"J.","email":"","middleInitial":"F.","affiliations":[{"id":6706,"text":"Woods Hole Oceanographic Institution,","active":true,"usgs":false}],"preferred":false,"id":538152,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70180931,"text":"70180931 - 1989 - The Resurrection Peninsula ophiolite","interactions":[],"lastModifiedDate":"2018-07-07T17:46:58","indexId":"70180931","displayToPublicDate":"1989-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"title":"The Resurrection Peninsula ophiolite","docAbstract":"The Resurrection Peninsula forms the east side of Resurrection Bay (fig. 3). Relief ranges from 437 m (1,434 ft) at the southern end of the peninsula to more than 1,463 m (4,800 ft) opposite the head of the bay. All rock units composing the informally named Resurrection Peninsula ophiolite of Nelson and others (1987) are visible or accessible by boat.
\"Ophiolite\" has been a geologic term since 1827 (Coleman, 1977). The term \"ophiolite\" initially referred to the rock serpentinite; the Greek root \"ophi\" (meaning snake or serpent) alluded to the greenish, mottled, and shiny appearance of serpentinites. In 1927, Steinmann described a rock association in the Alps, sometimes known as the \"Steinmann Trinity', consisting of serpentine, diabase and spilitic lavas, and chert. Recognition of this suite led to the idea that ophiolites represent submarine magmatism that took place early in the development of a eugeosyncline. In the early 1970s the Steinmann Trinity was reconsidered in light of the plate tectonic theory, new petrologic studies, and the recognition of abducted oceanic lithosphere in orogenic belts of the world. In 1972 at a Geological Society of America Penrose Conference (Anonymous, 1972) the term \"ophiolite\" was defined as a distinctive assemblage of mafic to ultramafic rocks, with no emphasis on their origin. A complete ophiolite should contain, from bottom to top:
1) Tectonized ultramafic rocks (more or less serpentinized)
2) Gabbro complex containing cumulus textures and commonly cumulus peridotites
3) Mafic sheeted-dike complex, grading upward into;
4) Submarine pillow lavas of basaltic composition. Common associated rock types include plagiogranite (Na-rich) and an overlying sedimentary section typically dominated by chert.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Guide to the ceology of the Resurrection Bay - Eastern Kenai Fjords area","largerWorkSubtype":{"id":15,"text":"Monograph"},"language":"English","publisher":"Alaska Geological Society","usgsCitation":"Nelson, S.W., Miller, M.L., and Dumoulin, J.A., 1989, The Resurrection Peninsula ophiolite, chap. of Guide to the ceology of the Resurrection Bay - Eastern Kenai Fjords area, p. 9-20.","productDescription":"12 p.","startPage":"9","endPage":"20","numberOfPages":"13","costCenters":[{"id":114,"text":"Alaska Science Center","active":true,"usgs":true}],"links":[{"id":335018,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":335016,"rank":1,"type":{"id":15,"text":"Index Page"},"url":"https://archives.datapages.com/data/alaska/data/022/022001/9_akgs0220009.htm"},{"id":335017,"rank":2,"type":{"id":15,"text":"Index Page"},"url":"https://www.alaskageology.org/pubfieldbooks.htm","text":"AGS Publications list: Item #FG13"}],"country":"United States","state":"Alaska","otherGeospatial":"Resurrection Peninsula","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -149.43878173828125,\n 59.796489325638376\n ],\n [\n -149.43878173828125,\n 60.20298075456985\n ],\n [\n -149.04052734375,\n 60.20298075456985\n ],\n [\n -149.04052734375,\n 59.796489325638376\n ],\n [\n -149.43878173828125,\n 59.796489325638376\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"589c3c50e4b0efcedb741120","contributors":{"editors":[{"text":"Nelson, Steven W.","contributorId":74024,"corporation":false,"usgs":true,"family":"Nelson","given":"Steven","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":662891,"contributorType":{"id":2,"text":"Editors"},"rank":1},{"text":"Hamilton, Thomas D.","contributorId":91474,"corporation":false,"usgs":true,"family":"Hamilton","given":"Thomas","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":662892,"contributorType":{"id":2,"text":"Editors"},"rank":2}],"authors":[{"text":"Nelson, Steven W.","contributorId":74024,"corporation":false,"usgs":true,"family":"Nelson","given":"Steven","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":662888,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Miller, Marti L. 0000-0003-0285-4942 mlmiller@usgs.gov","orcid":"https://orcid.org/0000-0003-0285-4942","contributorId":561,"corporation":false,"usgs":true,"family":"Miller","given":"Marti","email":"mlmiller@usgs.gov","middleInitial":"L.","affiliations":[{"id":119,"text":"Alaska Science Center Geology Minerals","active":true,"usgs":true}],"preferred":true,"id":662889,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Dumoulin, Julie A. 0000-0003-1754-1287 dumoulin@usgs.gov","orcid":"https://orcid.org/0000-0003-1754-1287","contributorId":203209,"corporation":false,"usgs":true,"family":"Dumoulin","given":"Julie","email":"dumoulin@usgs.gov","middleInitial":"A.","affiliations":[{"id":114,"text":"Alaska Science Center","active":true,"usgs":true},{"id":119,"text":"Alaska Science Center Geology Minerals","active":true,"usgs":true}],"preferred":true,"id":662890,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70137845,"text":"70137845 - 1989 - Inner shelf deposits of the Louisiana-Mississippi-Alabama region, Gulf of Mexico","interactions":[],"lastModifiedDate":"2015-01-13T12:42:17","indexId":"70137845","displayToPublicDate":"1989-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1871,"text":"Gulf Coast Association of Geological Societies Transactions","active":true,"publicationSubtype":{"id":10}},"title":"Inner shelf deposits of the Louisiana-Mississippi-Alabama region, Gulf of Mexico","docAbstract":"The late Quaternary morphology, shallow stratigraphy and sediment distribution of the Louisiana-Mississippi-Alabama inner shelf region are the product of transgressive and regressive sedimentary processes. Shelf sedimentary facies were deposited by deltaic progradation, followed by shoreface erosion and submergence. This information is based on interpretations and synthesis of more than 4,160 mi (6,700 km) of high resolution seismic profiles, 75 grab samples, and 77 vibracores.
\n\n
The shelf can be divided into two main depositional regions. The southwestern region, east and south of the Mississippi River plain, was formed by early Holocene delta complexes, overlying a late Wisconsinan delta. Deposits of the late Wisconsinan delta consist of well-defined coarsening-upward sequences and represent deltaic progradation during low sea level stands. The relatively recent Mississippi delta complexes have deposits which consist of fine-grained sands, silt and clay. With the late Holocene rise in sea level, asymmetrical sand ridges (16 ft, or 5 m, relief) have formed due to marine reworking of shoreline features.
\n\n
The northeastern region, offshore of the Mississippi-Alabama barrier islands, was formed by Pleistocene fluvial systems and Recent shoreface erosion and ravinement. Underlying the relatively thin Holocene sediment cover are relict fluvial sands which were deposited during the late Wisconsinan lowstand. Subsequent sea level rise allowed marine processes to rework and redistribute sediments forming the nearshore fine-grained facies and shelf sands sheet.
","language":"English","publisher":"Gulf Coast Association of Geological Societies","usgsCitation":"Kindinger, J.L., Penland, S., Williams, S.J., and Suter, J.R., 1989, Inner shelf deposits of the Louisiana-Mississippi-Alabama region, Gulf of Mexico: Gulf Coast Association of Geological Societies Transactions, v. 39, p. 413-420.","productDescription":"8 p.","startPage":"413","endPage":"420","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":186,"text":"Coastal and Marine Geology Program","active":true,"usgs":true}],"links":[{"id":297177,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":297176,"rank":1,"type":{"id":15,"text":"Index Page"},"url":"https://archives.datapages.com/data/gcags/data/039/039001/0413.htm"}],"country":"United States","otherGeospatial":"Gulf of Mexico","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -80.595703125,\n 25.045792240303445\n ],\n [\n -95.44921875,\n 17.895114303749153\n ],\n [\n -100.546875,\n 27.293689224852407\n ],\n [\n -82.96875,\n 32.99023555965106\n ],\n [\n -80.595703125,\n 25.045792240303445\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"39","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"54dd2bd6e4b08de9379b350c","contributors":{"authors":[{"text":"Kindinger, Jack L. jkindinger@usgs.gov","contributorId":815,"corporation":false,"usgs":true,"family":"Kindinger","given":"Jack","email":"jkindinger@usgs.gov","middleInitial":"L.","affiliations":[{"id":574,"text":"St. Petersburg Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":false,"id":538162,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Penland, Shea","contributorId":88401,"corporation":false,"usgs":false,"family":"Penland","given":"Shea","email":"","affiliations":[{"id":5115,"text":"Louisiana State University","active":true,"usgs":false}],"preferred":false,"id":538163,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Williams, S. Jeffress 0000-0002-1326-7420 jwilliams@usgs.gov","orcid":"https://orcid.org/0000-0002-1326-7420","contributorId":2063,"corporation":false,"usgs":true,"family":"Williams","given":"S.","email":"jwilliams@usgs.gov","middleInitial":"Jeffress","affiliations":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":true,"id":538164,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Suter, John R.","contributorId":42362,"corporation":false,"usgs":false,"family":"Suter","given":"John","email":"","middleInitial":"R.","affiliations":[{"id":5115,"text":"Louisiana State University","active":true,"usgs":false}],"preferred":false,"id":538165,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70137839,"text":"70137839 - 1989 - Holocene sand shoals offshore of the Mississippi River delta plain","interactions":[],"lastModifiedDate":"2015-01-13T11:30:41","indexId":"70137839","displayToPublicDate":"1989-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1871,"text":"Gulf Coast Association of Geological Societies Transactions","active":true,"publicationSubtype":{"id":10}},"title":"Holocene sand shoals offshore of the Mississippi River delta plain","docAbstract":"Offshore of the Mississippi River delta plain lies a series of Holocene sand shoals marking the position of ancient submerged shorelines associated with younger shelf-phase delta plains. These submerged shorelines represent positions when sea level stood lower than present. Short periods of rapid sea level rise during the Holocene transgression, in combination with subsidence, led to the submergence of these sandy shorelines, which can be recognized at the -33 ft (-10 m) and -66 ft (-20 m) isobaths on the Louisiana continental shelf
\n\n
The -33 ft (-10 m) shoreline trend is represented by Trinity Shoal and Ship Shoal, which are associated with the late Holocene Mississippi River delta plain. Trinity Shoal is derived from the Cypremont-Sale delta complex and is located 12 mi (20 km) offshore of Marsh Island. This shoal is 22 mi (35 km) long, 5 mi (8 km) wide, and 16 - 20 ft (5 - 6 m) thick. The facies relationships indicate that Trinity Shoal is a submerged barrier system in the initial stages of shoreface reworking. To the east is Ship Shoal which is associated with the Maringouin-Teche delta complex. This shoal is located 12 mi (20 km) offshore of the Isles Dernieres and is 31 mi (50 km) long, 5 - 6 mi (8 - 10 km) wide, and 13 - 20 ft (4 - 6 m) thick. The facies relationships indicate that Ship Shoal is a marine sand body derived from shoreface reworking of a submerged barrier island.
\n\n
The -66 ft (-20 m) shoreline trend is represented by the Outer Shoal and St. Bernard Shoals, which are associated with the early Mississippi River delta plain. The Outer Shoal is a low relief sand body, which lies seaward of Ship Shoal immediately west of the Mississippi Canyon. The eastern continuation of the -66 ft (-20 m) shoreline trend is the St. Bernard Shoals, which lie 16 mi (25 km) offshore of the Chandeleur Islands. In contrast to the other shoal systems, the St. Bernard Shoals form a shore-parallel zone of more than seven smaller sand shoals which, in many respects, are similar to a shore-oblique sand-ridge field.
\nCollectively, these sand shoals represent a large potential source of aggregate for shoreline restoration and erosion control as well as possible hard mineral resources. Scientifically, these shoals provide insight into the processes which control coastal evolution and shelf sand development under the condition of relative sea level rise.
","language":"English","publisher":"Gulf Coast Association of Geological Societies","usgsCitation":"Penland, S., Suter, J.R., McBride, R., Williams, S.J., Kindinger, J.L., and Boyd, R., 1989, Holocene sand shoals offshore of the Mississippi River delta plain: Gulf Coast Association of Geological Societies Transactions, v. 39, p. 471-480.","productDescription":"10 p.","startPage":"471","endPage":"480","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":186,"text":"Coastal and Marine Geology Program","active":true,"usgs":true}],"links":[{"id":297171,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":297170,"rank":1,"type":{"id":15,"text":"Index Page"},"url":"https://archives.datapages.com/data/gcags/data/039/039001/0471.htm"}],"country":"United States","otherGeospatial":"Mississippi River","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -92.83447265624999,\n 30.20211367909724\n ],\n [\n -89.07714843749999,\n 30.259067203213018\n ],\n [\n -89.5166015625,\n 46.28622391806708\n ],\n [\n -93.71337890625,\n 46.49839225859763\n ],\n [\n -92.83447265624999,\n 30.20211367909724\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"39","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"54dd2bc6e4b08de9379b34c2","contributors":{"authors":[{"text":"Penland, Shea","contributorId":88401,"corporation":false,"usgs":false,"family":"Penland","given":"Shea","email":"","affiliations":[{"id":5115,"text":"Louisiana State University","active":true,"usgs":false}],"preferred":false,"id":538143,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Suter, John R.","contributorId":42362,"corporation":false,"usgs":false,"family":"Suter","given":"John","email":"","middleInitial":"R.","affiliations":[{"id":5115,"text":"Louisiana State University","active":true,"usgs":false}],"preferred":false,"id":538144,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"McBride, Randolph A.","contributorId":48711,"corporation":false,"usgs":false,"family":"McBride","given":"Randolph A.","affiliations":[{"id":5115,"text":"Louisiana State University","active":true,"usgs":false}],"preferred":false,"id":538145,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Williams, S. Jeffress 0000-0002-1326-7420 jwilliams@usgs.gov","orcid":"https://orcid.org/0000-0002-1326-7420","contributorId":2063,"corporation":false,"usgs":true,"family":"Williams","given":"S.","email":"jwilliams@usgs.gov","middleInitial":"Jeffress","affiliations":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":true,"id":538146,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Kindinger, Jack L. jkindinger@usgs.gov","contributorId":815,"corporation":false,"usgs":true,"family":"Kindinger","given":"Jack","email":"jkindinger@usgs.gov","middleInitial":"L.","affiliations":[{"id":574,"text":"St. Petersburg Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":false,"id":538147,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Boyd, Ron","contributorId":54737,"corporation":false,"usgs":false,"family":"Boyd","given":"Ron","email":"","affiliations":[],"preferred":false,"id":538148,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":1000084,"text":"1000084 - 1989 - Migration and control of purple loosestrife (Lythrum salicaria L.) along highway corridors","interactions":[],"lastModifiedDate":"2016-03-21T11:54:23","indexId":"1000084","displayToPublicDate":"1989-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1547,"text":"Environmental Management","active":true,"publicationSubtype":{"id":10}},"title":"Migration and control of purple loosestrife (Lythrum salicaria L.) along highway corridors","docAbstract":"The east-west density gradient and the pattern and mode of migration of the wetland exotic, purple loosestrife (Lythrum salicaria L.), were assessed in a survey of populations along the New York State Thruway from Albany to Buffalo to determine if the highway corridor contributed to the spread of this species. During the peak flowering season of late July to early August, individual colonies of purple loosestrife were identified and categorized into three size classes in parallel belt transects consisting of the median strip and highway rights-of-way on the north and south sides of the road. Data were also collected on the presence of colonies adjacent to the corridor and on highway drainage patterns. Although a distinct east-west density gradient existed in the corridor, it corresponded to the gradient on adjacent lands and was greatly influenced by a major infestation at Montezuma National Wildlife Refuge. The disturbed highway corridor served as a migration route for purple loosestrife, but topographic features dictated that this migration was a short-distance rather than long-distance process. Ditch and culvert drainage patterns increased the ability of purple loosestrife to migrate to new wetland sites. Management strategies proposed to reduce the spread of this wetland threat include minimizing disturbance, pulling by hand, spraying with glyphosate, disking, and mowing.
","language":"English","publisher":"Springer","doi":"10.1007/BF01874916","usgsCitation":"Wilcox, D.A., 1989, Migration and control of purple loosestrife (Lythrum salicaria L.) along highway corridors: Environmental Management, v. 13, no. 3, p. 365-370, https://doi.org/10.1007/BF01874916.","productDescription":"6 p.","startPage":"365","endPage":"370","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":324,"text":"Great Lakes Science Center","active":true,"usgs":true}],"links":[{"id":132835,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"13","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a60e4b07f02db6353ce","contributors":{"authors":[{"text":"Wilcox, Douglas A.","contributorId":36880,"corporation":false,"usgs":true,"family":"Wilcox","given":"Douglas","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":308053,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":44109,"text":"ofr89430 - 1989 - Surficial geologic map of the Hampton 7.5-minute quadrangle (east half of the Exeter 7.5 x 15 minute quadrangle), New Hampshire-Massachusetts","interactions":[],"lastModifiedDate":"2023-05-05T19:50:15.450233","indexId":"ofr89430","displayToPublicDate":"1989-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":330,"text":"Open-File Report","code":"OFR","onlineIssn":"2331-1258","printIssn":"0196-1497","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"89-430","title":"Surficial geologic map of the Hampton 7.5-minute quadrangle (east half of the Exeter 7.5 x 15 minute quadrangle), New Hampshire-Massachusetts","docAbstract":"No abstract available.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ofr89430","usgsCitation":"Koteff, C., Gephart, G.D., and Schafer, J.P., 1989, Surficial geologic map of the Hampton 7.5-minute quadrangle (east half of the Exeter 7.5 x 15 minute quadrangle), New Hampshire-Massachusetts: U.S. Geological Survey Open-File Report 89-430, 1 Plate: 26.85 × 28.03 inches, https://doi.org/10.3133/ofr89430.","productDescription":"1 Plate: 26.85 × 28.03 inches","costCenters":[],"links":[{"id":162792,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"},{"id":81497,"rank":3,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/of/1989/0430/plate-1.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":398165,"rank":2,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_17684.htm","linkFileType":{"id":5,"text":"html"}}],"scale":"24000","country":"United States","state":"Massachusetts, New Hampshire","otherGeospatial":"Exeter 7.5 x 15 minute quadrangle, Hampton 7.5 minute quadrangle","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -70.875,\n 42.875\n ],\n [\n -70.75,\n 42.875\n ],\n [\n -70.75,\n 43 \n ],\n [\n -70.875,\n 43\n ],\n [\n -70.875,\n 42.875\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4ae3e4b07f02db68907e","contributors":{"authors":[{"text":"Koteff, Carl","contributorId":73172,"corporation":false,"usgs":true,"family":"Koteff","given":"Carl","email":"","affiliations":[],"preferred":false,"id":229172,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Gephart, Gregory David","contributorId":79350,"corporation":false,"usgs":true,"family":"Gephart","given":"Gregory","email":"","middleInitial":"David","affiliations":[],"preferred":false,"id":871928,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Schafer, John Phillip","contributorId":52625,"corporation":false,"usgs":true,"family":"Schafer","given":"John","email":"","middleInitial":"Phillip","affiliations":[],"preferred":false,"id":229171,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70015662,"text":"70015662 - 1989 - The hydrologic reponses to development in regional sedimentary aquifers","interactions":[],"lastModifiedDate":"2024-03-19T23:02:43.830399","indexId":"70015662","displayToPublicDate":"1989-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3825,"text":"Groundwater","active":true,"publicationSubtype":{"id":10}},"title":"The hydrologic reponses to development in regional sedimentary aquifers","docAbstract":"The hydrologic response to development of three of the most heavily pumped sedimentary aquifer systems in the United States is similar in some aspects and different in others. In the semiarid West, an unconfined sand aquifer and a confined sand and clay aquifer system have been subjected to withdrawals that are far greater than predevelopment recharge rates. As a result, the aquifers have large losses of ground water from storage. In the humid East, pumpage from a carbonate aquifer system has resulted in induced recharge and diversion of natural discharge with insignificant loss from storage. However, the following responses to development are common in all three aquifer systems: (1) ground-water circulation has increased,
(2) rates of recharge have increased—mostly due to recirculation of pumped ground water, or infiltration of imported surface water used for irrigation in the semiarid West,
(3) locations of recharge areas have changed, and (4) natural discharge has decreased.
Regional water-level declines associated with ground- water development are inevitably accompanied by some combination of elastic compaction of aquifer material, inelastic compaction of fine-grained sediments and land subsidence, dewatering of aquifer material near pumping centers, and induced formation of sinkholes. The degree to which these changes occur is dependent on: (1) rates of pumping in relation to available recharge, and (2) lithology, specifically the proportion of sand, gravel, silt, clay, and carbonate rock that comprise the aquifer system.
Constraints on the current stress regime of the actively extending northern Basin and Range province are provided by deformation data (focal mechanisms and fault slip studies), hydraulic fracturing in situ stress measurements, borehole elongation (“breakouts”) analyses, and alignment of young volcanic vents. The integrated data indicate significant variations both in principal stress orientations and magnitudes. An approximately E-W least principal stress direction appears to characterize both the eastern and western margins of the Basin and Range province, whereas in the active interior parts of the province extension occurs in response to a least principal stress oriented NW to N60°W. The contrast in stress orientations between the province boundaries and in the interior suggests that along the margins the least principal stress direction may be locally controlled by the generally northerly trending profound lithospheric discontinuities associated with these margins. Active deformation along the southeastern and western province margins is characterized by a combination of strike-slip and normal faulting. Focal mechanisms along northeastern province margin (Wasatch front) and in central Nevada indicate a combination of normal and oblique-normal faulting. Temporal, regional, and depth-dependent variations in the relative magnitudes of the vertical and maximum horizontal stresses can explain much of the observed variations in deformation styles. However, some depth variation in faulting style inferred from focal mechanisms may be apparent and simply a function of the attitude of fault planes being reactivated. Evidence for significant temporal variation (or multiple cycles of variation) in relative stress magnitude comes from the Sierran front-Basin and Range boundary region where recent earthquakes are predominantly strike slip, whereas the profound relative vertical relief across the Sierra frontal fault zone in the last 9–10 m.y. implies a normal faulting stress regime. Using the best data on stress orientation, relative stress magnitudes are constrained from slip vectors of major earthquakes and young fault displacements. Analysis of well-constrained slip vectors in the Owens Valley, California, area indicate that large temporal variations in the magnitude of the approximately N-S oriented maximum horizontal stress are required to explain dominantly dip-slip and strike-slip offsets on subparallel faults. Similar faulting relations are observed throughout much of the boundary zone between the Basin and Range-Sierra Nevada (including the Walker Lane belt). Along the eastern province margin in the Wasatch front area in Utah, available data suggest that the maximum and minimum horizontal stresses may be approximately equal at depths of <4–5 km. Earthquake focal mechanisms in this area suggest more variability in relative magnitude of the two horizontal stresses with depth. Furthermore, superimposed sets of young fault striae along a segment of the Wasatch fault also indicate temporal variations of relative stress magnitudes. Sources of regional and temporal variations in the stress field may be linked to variable shear tractions applied to the base of the brittle crust related to intrusion, thermally induced flow, and the influence of the San Andreas plate boundary. Although difficult to date accurately, the fault slip data suggest that the temporal variations in relative magnitudes stress may occur on the time scale of both a single major earthquake cycle (1000–5000 years) and multiple earthquake cycles (10,000+ years).
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB094iB06p07105","issn":"01480227","usgsCitation":"Zoback, M., 1989, State of stress and modern deformation of the northern Basin and Range Province: Journal of Geophysical Research Solid Earth, v. 94, no. B6, p. 7105-7128, https://doi.org/10.1029/JB094iB06p07105.","productDescription":"24 p.","startPage":"7105","endPage":"7128","numberOfPages":"24","costCenters":[],"links":[{"id":224261,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"94","issue":"B6","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"505b96cfe4b08c986b31b710","contributors":{"authors":[{"text":"Zoback, M.L.","contributorId":12982,"corporation":false,"usgs":true,"family":"Zoback","given":"M.L.","email":"","affiliations":[],"preferred":false,"id":371098,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70015612,"text":"70015612 - 1989 - Comparison of geoelectrical/tectonic models for suture zones in the western U.S.A. and eastern Europe: are black shales a possible source of high conductivities?","interactions":[],"lastModifiedDate":"2013-02-13T13:17:28","indexId":"70015612","displayToPublicDate":"1989-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3071,"text":"Physics of the Earth and Planetary Interiors","active":true,"publicationSubtype":{"id":10}},"title":"Comparison of geoelectrical/tectonic models for suture zones in the western U.S.A. and eastern Europe: are black shales a possible source of high conductivities?","docAbstract":"Large-scale geoelectrical anomalies have been mapped with geomagnetic depth sounding (GDS) and magnetotelluric (MT) surveys in the Carpathian Mountains region. These anomalies are associated with the zone of closure between stable Europe and a complex of microplates in front of the converging African plate. The zone of closure, or suture zone, is largely occupied by an extensive deformed flysch belt. The models derived to fit the observed geoelectrical data are useful in the study of other suture zones, and Carpathian structures have been compared with areas currently being studied in the western Cordillera of the U.S.A. Models derived for a smaller-scale suture zone mapped in western Washington State have features that are similar to the Carpathian models. The geoelectrical models for both the Carpathian and Washington anomalies require dipping conductive slabs of 1-5 ?? m material that extends to depths > 20 km. In both instances there is evidence that these materials may merge with lower crustal-mantle conductors along the down-dip margins of the slab. The main conductive units are interpreted to be sedimentary rocks that have been partially subducted due to collisional processes. Heat flow is low in both regions and it is difficult to explain fully the deep conduction mechanisms; however, evidence suggests that the conduction at depth may include electronic conduction in sulfide mineral or carbon films as well as ionic conduction in fluids or partial melt. ?? 1989.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Physics of the Earth and Planetary Interiors","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier","publisherLocation":"Amsterdam, Netherlands","doi":"10.1016/0031-9201(89)90007-1","issn":"00319201","usgsCitation":"Stanley, W.D., 1989, Comparison of geoelectrical/tectonic models for suture zones in the western U.S.A. and eastern Europe: are black shales a possible source of high conductivities?: Physics of the Earth and Planetary Interiors, v. 53, no. 3-4, p. 228-238, https://doi.org/10.1016/0031-9201(89)90007-1.","startPage":"228","endPage":"238","numberOfPages":"11","costCenters":[],"links":[{"id":267326,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0031-9201(89)90007-1"},{"id":224431,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"53","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f866e4b0c8380cd4d098","contributors":{"authors":[{"text":"Stanley, W. D.","contributorId":86756,"corporation":false,"usgs":true,"family":"Stanley","given":"W.","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":371368,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70016032,"text":"70016032 - 1989 - Geochemical evidence for Paleozoic oil in Lower Cretaceous O Sandstone, northern Denver basin","interactions":[],"lastModifiedDate":"2023-01-19T15:28:20.119654","indexId":"70016032","displayToPublicDate":"1989-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":701,"text":"American Association of Petroleum Geologists Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"Geochemical evidence for Paleozoic oil in Lower Cretaceous O Sandstone, northern Denver basin","docAbstract":"Organic geochemical properties of the oil produced from the Lower Cretaceous O sandstone on the eastern flank of the Denver basin indicate that this oil has been derived from a different source rock than other Cretaceous oils in the basin. O sandstone oil is characterized by low pristane/phytane ratio, high isoprenoid/n-alkane ratios, high asphaltene content, high sulfur content, and slight predominance of even-carbon numbered n-alkanes in the C25+ fraction. These features are evidence of a Paleozoic source and indicate a carbonate rock is the likely source. Preliminary source rock evaluation and correlation data suggest that calcareous black shales and marls of Middle Pennsylvanian (Desmoinesian) age are the source of the O sandstone oil. This is the first rep rted occurrence of oil from Paleozoic source rocks in a Cretaceous reservoir in the Denver basin.
Two important implications for further exploration are evident if vertical migration from Paleozoic source rocks has occurred. First, Paleozoic rocks of Middle Pennsylvanian age or younger are potential exploration objectives where reservoirs and suitable trapping mechanisms are present. Second, future exploration for oil in the O sandstone and upper Paleozoic rocks should consider stratigraphic relationships between possible source and reservoir rocks and possible migration conduits.
","language":"English","publisher":"American Association of Petroleum Geologists","doi":"10.1306/44B4A2C6-170A-11D7-8645000102C1865D","usgsCitation":"Clayton, J., 1989, Geochemical evidence for Paleozoic oil in Lower Cretaceous O Sandstone, northern Denver basin: American Association of Petroleum Geologists Bulletin, v. 73, no. 8, p. 977-988, https://doi.org/10.1306/44B4A2C6-170A-11D7-8645000102C1865D.","productDescription":"12 p.","startPage":"977","endPage":"988","numberOfPages":"12","costCenters":[],"links":[{"id":222884,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Colorado","otherGeospatial":"northern Denver basin","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -104.7729022490935,\n 40.98779431670064\n ],\n [\n -104.7729022490935,\n 39.79304038553329\n ],\n [\n -102.14951374164394,\n 39.79304038553329\n ],\n [\n -102.14951374164394,\n 40.98779431670064\n ],\n [\n -104.7729022490935,\n 40.98779431670064\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"73","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a162be4b0c8380cd55086","contributors":{"authors":[{"text":"Clayton, J.L.","contributorId":76767,"corporation":false,"usgs":true,"family":"Clayton","given":"J.L.","email":"","affiliations":[],"preferred":false,"id":372385,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70015303,"text":"70015303 - 1989 - Constraints from fluid inclusions on sulfide precipitation mechanisms and ore fluid migration in the Viburnum Trend lead district, Missouri","interactions":[],"lastModifiedDate":"2024-01-04T17:36:41.115494","indexId":"70015303","displayToPublicDate":"1989-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1472,"text":"Economic Geology","active":true,"publicationSubtype":{"id":10}},"title":"Constraints from fluid inclusions on sulfide precipitation mechanisms and ore fluid migration in the Viburnum Trend lead district, Missouri","docAbstract":"Measurements on fluid inclusions in hydrothermal dolomite cements place constraints on sulfide precipitation mechanisms and on the thermal-hydrologic processes which formed the Viburnum Trend Mississippi Valley-type lead district. Homogenization temperatures and freezing point depressions were determined for fluid inclusions in Bonneterre Dolomite-hosted dolomite cements in mine samples, as well as drill core from up to 13 km outside of the district. A well-defined cathodoluminescent zonation distinguishes dolomite growth zones in the Vi-burnurn Trend as older or younger than main-stage mineralization (octahedral galena) and facilitates correlation with other dolomites outside the Viburnum Trend.Homogenization temperatures and salinities in samples from mines are not systematically different from those of samples outside of the district. Medians of homogenization temperature distributions differ by not more than 25 degrees C, so that a temperature gradient, if present, should not have exceeded approximately 25 degrees C within the study area. These observations are interpreted to indicate that the Viburnum Trend was not strongly thermally anomalous with respect to surrounding country rock and that fluid flow occurred on a broad scale through not only the Lamotte Sandstone but through the overlying Cambrian carbonates as well.The absence of a significant, recognizable decrease in temperature either vertically within the section or east-west across the district, coupled with the minor amount of silica in the district, argues against cooling as a primary cause of sulfide precipitation. Fluids whose primary aquifer was the Lamotte Sandstone, predominantly a quartz arenite, should have been in equilibrium with quartz. Quartz in the Viburnum Trend occurs as a minor, drusy, vug-lining phase, but the district lacks the intense silicification found in other Mississippi Valley-type districts such as Tri-State (Oklahoma, Kansas, Missouri). Quartz solubility is strongly temperature dependent and, under equilibrium conditions, a decrease of 10 degrees C or more should have precipitated at least as many moles of silica as galena (assuming a galena solubility of between 1 and 10 ppm). Clearly this is not the case, as galena is far more abundant than quartz in the Viburnum Trend.Ice final-melting temperatures (T m ) in fluid inclusions generally range from -14 degrees to -27 degrees C for primary dolomite-hosted inclusions. Using these T m values and cation ratios for the inclusion fluids, absolute concentrations for the individual cations and chloride were calculated using the thermochemical model of Spencer et al. (1990). The corresponding high but variable salinities, 3.9 to 5.9 chloride molality, are evidence for the presence of more than one distinct fluid during mineralization.In a reduced sulfur mineralization model with Pb carried as chloride complexes, dilution is also a possible sulfide precipitation mechanism. The difference in Pb solubility (for an equal quantity of reduced sulfur) in the extremes of the chloride concentration range, 3.9 vs. 5.9 molal, reaches 1 ppm only for pH values below approximately 4.5. Accepting 1 ppm as a minimum metal concentration for a viable ore-forming fluid, dilution only appears capable of precipitating sulfides in a fluid with pH near the lower limit of values considered geologically reasonable or attainable.Dolomite cements hosting warm (approximately 105 degrees -125 degrees C) saline fluid inclusions are ubiquitous in the porous dolomitic facies of the Bonneterre Dolomite. Based on stratigraphic reconstructions, however, it is unlikely that the Bonneterre was buried deeper than 1.5 km. The distribution of warm inclusions beyond the Viburnum Trend district implies that fluid migration was regional in scale. Fluid inclusion temperatures inconsistent with typical basement heat-flow-controlled geothermal gradients (25 degrees -35 degrees C/km) may be explained by long-distance migration of warm, basin-derived brines. Elevated temperatures observed in fluid inclusions at shallow stratigraphic depths are consistent with a gravity flow hydrologic system characterized by rapid flow rates and the capacity for advective heat transport.
","language":"English","publisher":"Society of Economic Geologists","doi":"10.2113/gsecongeo.84.7.1948","issn":"03610128","usgsCitation":"Rowan, E., and Leach, D.L., 1989, Constraints from fluid inclusions on sulfide precipitation mechanisms and ore fluid migration in the Viburnum Trend lead district, Missouri: Economic Geology, v. 84, no. 7, p. 1948-1965, https://doi.org/10.2113/gsecongeo.84.7.1948.","productDescription":"18 p.","startPage":"1948","endPage":"1965","numberOfPages":"18","costCenters":[],"links":[{"id":224360,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"84","issue":"7","noUsgsAuthors":false,"publicationDate":"1989-11-01","publicationStatus":"PW","scienceBaseUri":"5059fa09e4b0c8380cd4d8bd","contributors":{"authors":[{"text":"Rowan, E. L. 0000-0001-5753-6189","orcid":"https://orcid.org/0000-0001-5753-6189","contributorId":34921,"corporation":false,"usgs":true,"family":"Rowan","given":"E. L.","affiliations":[],"preferred":false,"id":370587,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Leach, D. L.","contributorId":18758,"corporation":false,"usgs":true,"family":"Leach","given":"D.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":370586,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ]}