Rhythmically layered anorthosite and gabbro are exposed in a 4–10-m thick interval at the base of the layered gabbro unit on North Arm Mountain, one of four massifs that compose the Bay of Islands ophiolite, Newfoundland. Within the rhythmically layered interval, up to 37 anorthosite layers 1–2 cm thick alternate with gabbroic layers 7–10 cm thick. Anorthosites are adcumulates (most contain <6ppm Zr) with 98–99% plagioclase (Plag) and 1–2% intergranular clinopyroxene (Cpx), whereas gabbros are adcumulates to mesocumulates (<6–20ppm Zr) with 35–55% Plag, and the balance olivine (Ol) + Cpx ± orthopyroxene (Opx). Average mineral compositions are: Ol mg-number [100 ×Mg/(Mg + Fe)]=84·9, NiO=0·13wt. % Plag An = 87·9; Cpx mg-number = 88·3, TiO2=0·20 wt %; and Opx mg-number = 85·7. Rare earth element (REE) concentrations in clinopyroxene and plagioclase are low throughout the rhythmically layered interval (<5 times chondrites). The rhythmically layered interval is sandwiched between thick layers of adcumulate to orthocumulate uniform gabbro with average modal proportions of 54% Plag-39% Cpx-3% Ol-4% Opx. Average mineral compositions are: Ol mg-number = 75·5, NiO = 0·08 wt. %; Plag An=69%6; Cpx mg-number = 81·2, TiO2 =0·53 wt. %, and Opx mg-number = 77·5. Clinopyroxene and plagioclase REE abundances are systematically higher in the uniform gabbro interval than in the rhythmically layered interval. Calculated fractional crystallization paths and correlated cryptic variation patterns suggest that uniform and rhythmically layered gabbros represent 20–30% in situ crystallization of two distinct magma batches, one more evolved and the other more primitive. When the more primitive magma entered the crystallization site of the NA300–301 gabbros, it is estimated to have been ∼40°C hotter than the resident evolved magma, and may have been chilled by contact with a magma chamber margin composed of uniform gabbro. In this model, chilling caused the liquid to become supercooled with respect to plagioclase nucleation temperatures, resulting in crystallization of gabbro deficient in plagioclase relative to equilibrium cotectic proportions. Subtraction of a plagioclase-poor melagabbro enriched the liquid in normative plagioclase, which in turn led to crystallization of an anorthosite layer. Alternating anorthosite and gabbro layers in the rhythmically layered interval built up by coupled and sustained variations in crystal nucleation and growth rates, and associated variations in liquid compositions at the crystallization front. Relatively stagnant magma-flow conditions may be required to accumulate substantial thicknesses of rhythmically layered cumulates by sustained oscillatory crystallization. The rarity of anorthosite-gabbro rhythmic phase layering on North Arm Mountain may indicate that convective magma currents in the Bay of Islands magma chamber were too vigorous for oscillatory crystallization to commonly occur.
","language":"English","publisher":"Oxford Academic","doi":"10.1093/petrology/31.1.1","issn":"00223530","usgsCitation":"Komor, S., and Elthon, D., 1990, Formation of anorthosite-Gabbro rhythmic phase layering: an example at North Arm Mountain, Bay of Isands ophiolite: Journal of Petrology, v. 31, no. 1, p. 1-50, https://doi.org/10.1093/petrology/31.1.1.","productDescription":"50 p.","startPage":"1","endPage":"50","numberOfPages":"50","costCenters":[],"links":[{"id":223312,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"31","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a134ee4b0c8380cd545dc","contributors":{"authors":[{"text":"Komor, S.C.","contributorId":21182,"corporation":false,"usgs":true,"family":"Komor","given":"S.C.","email":"","affiliations":[],"preferred":false,"id":373144,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Elthon, D.","contributorId":107434,"corporation":false,"usgs":true,"family":"Elthon","given":"D.","email":"","affiliations":[],"preferred":false,"id":373145,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70016316,"text":"70016316 - 1990 - Platinum-group element abundance and distribution in chromite deposits of the Acoje Block, Zambales Ophiolite Complex, Philippines","interactions":[],"lastModifiedDate":"2024-04-17T11:12:45.281981","indexId":"70016316","displayToPublicDate":"1990-01-01T00:00:00","publicationYear":"1990","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2302,"text":"Journal of Geochemical Exploration","active":true,"publicationSubtype":{"id":10}},"title":"Platinum-group element abundance and distribution in chromite deposits of the Acoje Block, Zambales Ophiolite Complex, Philippines","docAbstract":"Platinum-group elements (PGE) occur in ore-grade concentration in some of the chromite deposits related to the ultramafic section of the Acoje Block of the Zambales Ophiolite Complex. The deposits are of three types: Type 1 - associated with cumulate peridotites at the base of the crust; Type 2 - in dunite pods from the top 1 km of mantle harzburgite; and Type 3 - like Type 2, but in deeper levels of the harzburgite. Most of the deposites have chromite compositions that are high in Cr with Cr/(Cr + Al) (expressed as chromium index, Cr#) > 0.6; high-Al (Cr# < 0.6) chromite deposits are relatively rare, occurring as interspersed orebodies in regions of Types 2 and 3. Sulfide-bearing Type 1 high-Cr deposits are PGE-enriched; the high-Al deposits have lowest Ir and Pd. Among the PGEs, Ir ranges from <20 to 550 ppb, Rh from <100 to 1100 ppb, Rh from 0.7 to 760 ppb, Pt from <1.0 to 5960 ppb and Pd from <0.5 to 8350 ppb. Chondrite-normalized (CN) PGE patterns are diverse, and include those with both negative slope (Ir > Pd, thought to be characteristic of PGE-barren deposits) and positive slope (Ir < Pd, characteristic of PGE-rich deposits).
Iridium, Ru and Os commonly occur as micron-size laurite (sulfide) inclusions in unfractured chromite. Laurite and native Os are also found as inclusions in interstitial sulfides. Platinum and Pd occur as alloy inclusions (and possibly as solid solution) in interstitial Ni-Cu sulfides and as tellurobismuthides in serpentine and altered sulfides.
","language":"English","publisher":"Elsevier","doi":"10.1016/0375-6742(90)90086-P","issn":"03756742","usgsCitation":"Bacuta, G., Kay, R., Gibbs, A., and Lipin, B., 1990, Platinum-group element abundance and distribution in chromite deposits of the Acoje Block, Zambales Ophiolite Complex, Philippines: Journal of Geochemical Exploration, v. 37, no. 1, p. 113-145, https://doi.org/10.1016/0375-6742(90)90086-P.","productDescription":"33 p.","startPage":"113","endPage":"145","numberOfPages":"33","costCenters":[{"id":245,"text":"Eastern Mineral and Environmental Resources Science Center","active":true,"usgs":true}],"links":[{"id":223463,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"37","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a7c2de4b0c8380cd79840","contributors":{"authors":[{"text":"Bacuta, G.C. Jr.","contributorId":89013,"corporation":false,"usgs":true,"family":"Bacuta","given":"G.C.","suffix":"Jr.","email":"","affiliations":[],"preferred":false,"id":373165,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kay, R.W.","contributorId":61713,"corporation":false,"usgs":true,"family":"Kay","given":"R.W.","email":"","affiliations":[],"preferred":false,"id":373164,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Gibbs, A.K.","contributorId":94924,"corporation":false,"usgs":true,"family":"Gibbs","given":"A.K.","email":"","affiliations":[],"preferred":false,"id":373166,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Lipin, B. R.","contributorId":61031,"corporation":false,"usgs":true,"family":"Lipin","given":"B. R.","affiliations":[],"preferred":false,"id":373163,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70016524,"text":"70016524 - 1990 - Enigmatic eight-meter trace fossils in the Lower Pennsylvanian Lee sandstone, central Appalachian basin, Tennessee","interactions":[],"lastModifiedDate":"2024-06-20T11:42:18.746862","indexId":"70016524","displayToPublicDate":"1990-01-01T00:00:00","publicationYear":"1990","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2412,"text":"Journal of Paleontology","active":true,"publicationSubtype":{"id":10}},"title":"Enigmatic eight-meter trace fossils in the Lower Pennsylvanian Lee sandstone, central Appalachian basin, Tennessee","docAbstract":"Enigmatic tubular trace fossils up to eight meters long occur in the Lower Pennsylvanian Middlesboro Member of the Lee Formation. Two morphotypes occur: type 1 trace fossils are plain, smooth, vertical, nonbranching, parallel-walled, tubular structures; type 2 trace fossils branch, have walls with faint vertical striations, regularly or irregularly spaced nodes, and funnel-shaped terminations. Sandstone casts filling type 2 structures have helical spiral morphology, and, in rare individuals, faint meniscate fills have been observed. Both trace-fossil morphotypes have poorly cemented wall linings containing framboidal pyrite, amorphous carbon, quartz sand, and poorly preserved fecal material.
The trace fossils occur in a massive, structureless, channel-form sandstone, originating at the contact between a channel lag and the overlying massive fill. The stratigraphic sequence is interpreted to represent a barrier island transgressing an estuarine facies. A tidal inlet within the barrier facies scoured into the underlying estuarine sediments. Subsequent rapid filling of the inlet led to the deposition of the massive sandstone.
Origin of these structures is uncertain. The preponderance of evidence favors the hypothesis that the structures are escape burrows of animals that had colonized, or were concentrated in, the lag and were suddenly buried by the deposition of the massive sand. However, no likely burrower has been identified, and several characteristics of the structures and the enclosing sediments indicate that they may be completely inorganic in origin.
The plate tectonic setting, regional geology and certain aspects of the economic geology of the iron-rare-earth-niobium ore bodies at Bayan Obo, Inner Mongolia, China, were studied by a team of geologists from the Tianjin Geologic Research Academy and the U.S. Geological Survey between 1987 and 1989. These ore bodies were formed by hydrothermal replacement of Middle Proterozoic dolomite in an intra-continental rift setting. A variety of veins and/or dikes that have a carbonatitelike mineralogy cut the footwall clastic rocks and migmatites. A stockwork of veins occurs at several locations in the footwall. The hanging wall is a shale that has been converted to a K-metasomatite and has microcrystalline potassium feldspar as its principal constituent. This shale served as a sealing caprock that contained the chemical solutions that reacted with the dolomite and created the enormous concentration of mineralized rock in an 18-kilometer-long syncline. The rocks that host these ore bodies and the associated mineralized areas occur today as roof pendants in granitoid rocks of Permian age that were emplaced during a continent-to-continent collision during that period.
","language":"English","publisher":"Elsevier","doi":"10.1016/0024-4937(90)90040-8","issn":"00244937","usgsCitation":"Drew, L.J., Qingrun, M., and Weijun, S., 1990, The Bayan Obo iron-rare-earth-niobium deposits, Inner Mongolia, China: LITHOS, v. 26, no. 1-2, p. 43-65, https://doi.org/10.1016/0024-4937(90)90040-8.","productDescription":"23 p.","startPage":"43","endPage":"65","numberOfPages":"23","costCenters":[],"links":[{"id":224334,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"26","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505ba698e4b08c986b3211fb","contributors":{"authors":[{"text":"Drew, Lawrence J. ldrew@usgs.gov","contributorId":2635,"corporation":false,"usgs":true,"family":"Drew","given":"Lawrence","email":"ldrew@usgs.gov","middleInitial":"J.","affiliations":[{"id":245,"text":"Eastern Mineral and Environmental Resources Science Center","active":true,"usgs":true}],"preferred":false,"id":371714,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Qingrun, Meng","contributorId":24372,"corporation":false,"usgs":true,"family":"Qingrun","given":"Meng","email":"","affiliations":[],"preferred":false,"id":371713,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Weijun, Sun","contributorId":27874,"corporation":false,"usgs":true,"family":"Weijun","given":"Sun","email":"","affiliations":[],"preferred":false,"id":371712,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70015797,"text":"70015797 - 1990 - Combustion and leaching behavior of elements in the argonne premium coal samples","interactions":[],"lastModifiedDate":"2023-12-16T00:53:04.674835","indexId":"70015797","displayToPublicDate":"1990-01-01T00:00:00","publicationYear":"1990","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1506,"text":"Energy & Fuels","active":true,"publicationSubtype":{"id":10}},"title":"Combustion and leaching behavior of elements in the argonne premium coal samples","docAbstract":"Eight Argonne Premium Coal samples and two other coal samples were used to observe the effects of combustion and leaching on 30 elements. The results were used to infer the modes of occurrence of these elements. Instrumental neutron activation analysis indicates that the effects of combustion and leaching on many elements varied markedly among the samples. As much as 90% of the selenium and bromine is volatilized from the bituminous coal samples, but substantially less is volatilized from the low-rank coals. We interpret the combustion and leaching behavior of these elements to indicate that they are associated with the organic fraction. Sodium, although nonvolatile, is ion-exchangeable in most samples, particularly in the low-rank coal samples where it is likely to be associated with the organic constituents. Potassium is primarily in an ion-exchangeable form in the Wypdak coal but is in HF-soluble phases (probably silicates) in most other samples. Cesium is in an unidentified HNO3-soluble phase in most samples. Virtually all the strontium and barium in the low-rank coal samples is removed by NH4OAc followed by HCl, indicating that these elements probably occur in both organic and inorganic phases. Most tungsten and tantalum are in insoluble phases, perhaps as oxides or in organic association. Hafnium is generally insoluble, but as much as 65% is HF soluble, perhaps due to the presence of very fine grained or metamict zircon. We interpret the leaching behavior of uranium to indicate its occurrence in chelates and its association with silicates and with zircon. Most of the rare-earth elements (REE) and thorium appear to be associated with phosphates. Differences in textural relationships may account for some of the differences in leaching behavior of the REE among samples. Zinc occurs predominantly in sphalerite. Either the remaining elements occur in several different modes of occurrence (scandium, iron), or the leaching data are equivocal (arsenic, antimony, chromium, cobalt, and nickel). The results of these combustion and leaching experiments indicate that some previously held assumptions concerning modes of occurrence of elements in coal should be reconsidered.","language":"English","publisher":"American Chemical Society","doi":"10.1021/ef00024a024","issn":"08870624","usgsCitation":"Finkelman, R.B., Palmer, C., Krasnow, M., Aruscavage, P.J., Sellers, G., and Dulong, F., 1990, Combustion and leaching behavior of elements in the argonne premium coal samples: Energy & Fuels, v. 4, no. 6, p. 755-766, https://doi.org/10.1021/ef00024a024.","productDescription":"12 p.","startPage":"755","endPage":"766","numberOfPages":"12","costCenters":[],"links":[{"id":223125,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"4","issue":"6","noUsgsAuthors":false,"publicationDate":"2002-05-01","publicationStatus":"PW","scienceBaseUri":"5059f7e2e4b0c8380cd4cd54","contributors":{"authors":[{"text":"Finkelman, R. B.","contributorId":20341,"corporation":false,"usgs":true,"family":"Finkelman","given":"R.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":371792,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Palmer, C.A.","contributorId":81894,"corporation":false,"usgs":true,"family":"Palmer","given":"C.A.","email":"","affiliations":[],"preferred":false,"id":371797,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Krasnow, M.R.","contributorId":25952,"corporation":false,"usgs":true,"family":"Krasnow","given":"M.R.","email":"","affiliations":[],"preferred":false,"id":371794,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Aruscavage, P. J.","contributorId":41411,"corporation":false,"usgs":true,"family":"Aruscavage","given":"P.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":371795,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Sellers, G.A.","contributorId":21690,"corporation":false,"usgs":true,"family":"Sellers","given":"G.A.","email":"","affiliations":[],"preferred":false,"id":371793,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Dulong, F.T.","contributorId":81490,"corporation":false,"usgs":true,"family":"Dulong","given":"F.T.","affiliations":[],"preferred":false,"id":371796,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70015799,"text":"70015799 - 1990 - Distribution and dispersal of suspended particulate matter on the Ebro continental shelf, northwestern Mediterranean Sea","interactions":[],"lastModifiedDate":"2024-10-01T11:26:40.905564","indexId":"70015799","displayToPublicDate":"1990-01-01T00:00:00","publicationYear":"1990","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2667,"text":"Marine Geology","active":true,"publicationSubtype":{"id":10}},"title":"Distribution and dispersal of suspended particulate matter on the Ebro continental shelf, northwestern Mediterranean Sea","docAbstract":"The Kilbuck terrane in southwestern Alaska is a narrow, thin crustal sliver or flake of amphibolite facies orthogneiss. The igneous protolith of this gneiss was a suite of subduction-related platonic rocks. U-Pb data on zircons from trondhjemitic and granitic samples yield upper-intercept (igneous) ages of 2070 ±16 and 2040 ±74 Ma, respectively. Nd isotope data from these rocks suggest that a diorite-tonalite-trondhjemite suite (εNd [T] = +2.1 to +2.7; T is time of crystallization) evolved from partial melts of depleted mantle with no discernible contamination by older crust, whereas a coeval granitic pluton (εNd [T] = -5.7) contains a significant component derived from Archean crust. Orthogneisses with similar age and Nd isotope characteristics are found in the Idono complex 250 km to the north. Early Proterozoic rocks are unknown elsewhere in Alaska. However, Phanerozoic plutons cutting several \"continental\" terranes in Alaska (southern Brooks Range and Ruby, Seward, and Yukon-Tanana terranes) have Nd isotope compositions indicative of Early Proterozoic (or older) crustal components that could be correlative with rocks of the Kilbuck terrane. Rocks with similar igneous ages in cratonal North America are rare, and those few that are known have Nd isotope compositions distinct from those of the Kilbuck terrane. Conversely, provinces with Nd model ages off 2.0-2.1 Ga are characterized by extensive 1.8 Ga or younger plutonism, which is unknown in the Kilbuck terrane. At present the case for a North American parentage of the Kilbuck terrane is not compelling. The possibility that the Kilbuck terrane was displaced from provinces off similar age in other cratons (e.g., Australian, Baltic, Guiana, and west African shields), or from the poorly dated Siberian craton, cannot be excluded.
During 1983-1985, we studied the reproductive success of several species of aquatic birds (coots, ducks, shorebirds, and grebes) nesting at two sites in Merced County, California: a selenium-contaminated site (Kesterson Reservoir) and a nearby reference site (Volta Wildlife Area). We used a computer program (MICROMORT) developed for the analysis of radiotelemetry data (Heisey and Fuller 1985) to estimate nest success and cause-specific failure rates, and then compared these parameters and hatchability between sites and among years. Nest success and causes of failure varied by species, site, and year. The most important causes of nest failure were usually predation, desertion, and water-level changes. However, embryotoxicosis (mortality, deformity, and lack of embryonic development) was the most important cause of nest failure in Eared Grebes (Podiceps nigricollis) at Kesterson Reservoir. Embryotoxicosis also reduced the hatchability of eggs of all other species at Kesterson in one or more years; embryonic mortality occurred rarely at Volta, and abnormalities were not observed.
","language":"English","publisher":"Cooper Ornithological Society","doi":"10.2307/1368061","usgsCitation":"Ohlendorf, H.M., Hothem, R.L., and Welsh, D., 1989, Nest success, cause-specific nest failure, and hatchability of aquatic birds at selenium-contaminated Kesterson Reservoir and a reference site: The Condor, v. 91, no. 4, p. 787-796, https://doi.org/10.2307/1368061.","productDescription":"10 p.","startPage":"787","endPage":"796","costCenters":[{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true},{"id":651,"text":"Western Ecological Research Center","active":true,"usgs":true}],"links":[{"id":196610,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","county":"Merced County","otherGeospatial":"Kesterson Reservoir, Volta Wildlife Area","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -121.20597839355467,\n 36.86698689106877\n ],\n [\n -120.53375244140625,\n 36.86698689106877\n ],\n [\n -120.53375244140625,\n 37.35269280367274\n ],\n [\n -121.20597839355467,\n 37.35269280367274\n ],\n [\n -121.20597839355467,\n 36.86698689106877\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"91","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b24e4b07f02db6ae7c1","contributors":{"authors":[{"text":"Ohlendorf, Harry M.","contributorId":60291,"corporation":false,"usgs":true,"family":"Ohlendorf","given":"Harry","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":336034,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hothem, Roger L. roger_hothem@usgs.gov","contributorId":1721,"corporation":false,"usgs":true,"family":"Hothem","given":"Roger","email":"roger_hothem@usgs.gov","middleInitial":"L.","affiliations":[{"id":651,"text":"Western Ecological Research Center","active":true,"usgs":true}],"preferred":true,"id":336036,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Welsh, Daniel","contributorId":181869,"corporation":false,"usgs":false,"family":"Welsh","given":"Daniel","email":"","affiliations":[{"id":6711,"text":"University of Idaho, Moscow ID","active":true,"usgs":false}],"preferred":false,"id":336035,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":5230195,"text":"5230195 - 1989 - Habitat area requirements of breeding forest birds of the middle Atlantic states","interactions":[],"lastModifiedDate":"2014-08-13T13:07:19","indexId":"5230195","displayToPublicDate":"2009-06-09T10:33:00","publicationYear":"1989","noYear":false,"publicationType":{"id":4,"text":"Book"},"title":"Habitat area requirements of breeding forest birds of the middle Atlantic states","docAbstract":"Conservation of birds requires an understanding of their nesting requirements, including area as well as structural characteristics of the habitat. Previous studies have shown that many neotropical migrant bird species seem to depend on extensive forested areas, but the specific area requirements of individual species have not been clarified sufficiently to aid in design and management of effective preserves.
\nFor this 5-year study, bird and vegetation data were obtained at 469 points in forests ranging in area from 0.1 ha to more than 3,000 ha in Maryland and adjacent states. Data were analyzed first by stepwise regression to identify habitat factors that had the greatest influence on relative abundance of each bird species. In the relatively undisturbed mature forests studied, degree of isolation and area were significant predictors of relative abundance for more bird species than were any habitat variables. For species for which forest area was a significant predictor of abundance, we used logistic regression to examine the relationship between forest area and the probability of detecting the species.
\nIn managing forest lands for wildlife, top priority should go toward providing for the needs of area-sensitive or rare species rather than increasing species diversity per se. Avian species that occur in small and disturbed forests are generalists that are adapted to survival under edge conditions and need no special assistance from man. Forest reserves with thousands of hectares are required to have the highest probability of providing for the least common species of forest birds in a region. However, if preservation of large contiguous forest tracts is not a realistic option, results of this study suggest 2 alternative approaches. First, if other habitat attributes also are considered, smaller forests may provide suitable breeding sites for relatively rare species. Second, smaller tracts in close proximity to other forests may serve to attract or retain area-sensitive species.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Wildlife Monographs","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"The Wildlife Society","usgsCitation":"Robbins, C.S., Dawson, D.K., and Dowell, B.A., 1989, Habitat area requirements of breeding forest birds of the middle Atlantic states, v. 103, 34 p.","productDescription":"34 p.","startPage":"3","endPage":"34","numberOfPages":"32","costCenters":[{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true}],"links":[{"id":202573,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":292088,"type":{"id":15,"text":"Index Page"},"url":"https://www.jstor.org/stable/3830692"}],"country":"United States","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -79.6195,37.8886 ], [ -79.6195,39.8982 ], [ -75.0492,39.8982 ], [ -75.0492,37.8886 ], [ -79.6195,37.8886 ] ] ] } } ] }","volume":"103","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a80e4b07f02db64961d","contributors":{"authors":[{"text":"Robbins, Chandler S. crobbins@usgs.gov","contributorId":4275,"corporation":false,"usgs":true,"family":"Robbins","given":"Chandler","email":"crobbins@usgs.gov","middleInitial":"S.","affiliations":[{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true}],"preferred":true,"id":343708,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Dawson, Deanna K. ddawson@usgs.gov","contributorId":1257,"corporation":false,"usgs":true,"family":"Dawson","given":"Deanna","email":"ddawson@usgs.gov","middleInitial":"K.","affiliations":[{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true}],"preferred":true,"id":343707,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Dowell, Barbara A.","contributorId":93165,"corporation":false,"usgs":true,"family":"Dowell","given":"Barbara","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":343709,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":5210408,"text":"5210408 - 1989 - Falcons","interactions":[],"lastModifiedDate":"2012-02-02T00:15:14","indexId":"5210408","displayToPublicDate":"2009-06-09T09:23:17","publicationYear":"1989","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"seriesNumber":"13","title":"Falcons","docAbstract":"Four species of Falco occur in the northeastern United States. The gyrfalcon is a rare winter visitor. The peregrine falcon federally listed as endangered, is a migrant and through reestablishment is breeding and wintering locally throughout the northeast. The merlin is a migrant and uncommon winter bird. The American kestrel breeds, winters, and migrates in the northeast. A 22-year analysis of the American kestrel Breeding Bird Survey data showed populations to be stable in less developed areas and declining in more developed areas. By states, declines occurred in the more developed areas of New Hampshire, Massachusetts, Connecticut and Pennsylvania, and data indicate a decrease in American kestrels from 1957 to 1966, a decrease in merlins between 1967 and 1974 and a decrease in peregrine falcons between 1940 and 1975. Migration counts indicate decreasing American kestrel numbers from 1973 to 1986, but an increasing trend from 1934 to 1986.","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Proceedings of the Northeast Raptor Management Symposium and Workshop","largerWorkSubtype":{"id":4,"text":"Other Government Series"},"language":"English","publisher":"National Wildlife Federation.","usgsCitation":"Schueck, L., Fuller, M., and Seegar, W., 1989, Falcons, chap. of Proceedings of the Northeast Raptor Management Symposium and Workshop, p. 71-80.","productDescription":"353","startPage":"71","endPage":"80","numberOfPages":"353","costCenters":[{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true}],"links":[{"id":201082,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e49ffe4b07f02db5f7944","contributors":{"authors":[{"text":"Schueck, L.S.","contributorId":87257,"corporation":false,"usgs":true,"family":"Schueck","given":"L.S.","email":"","affiliations":[],"preferred":false,"id":328372,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Fuller, M.R.","contributorId":71278,"corporation":false,"usgs":true,"family":"Fuller","given":"M.R.","email":"","affiliations":[],"preferred":false,"id":328371,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Seegar, W.S.","contributorId":11301,"corporation":false,"usgs":true,"family":"Seegar","given":"W.S.","email":"","affiliations":[],"preferred":false,"id":328370,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":5210485,"text":"5210485 - 1989 - Snowy owl","interactions":[],"lastModifiedDate":"2012-02-02T00:15:16","indexId":"5210485","displayToPublicDate":"2009-06-09T09:23:17","publicationYear":"1989","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"seriesNumber":"13","title":"Snowy owl","docAbstract":"The snowy owl is a rare to uncommon, irregular winter visitor in the northeastern United States, decreasing southward in abundance except during incursion years, when it is more common and widely distributed. Although snowy owls are recorded in northern New England every winter, major incursions occur at approximately three to four year intervals. Limiting factors include food, habitat and human interference. Research is needed on the population ecology of this species and, perhaps more important, management goals must be directed towards public education emphasizing the value of snowy owls.","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Proceedings of the Northeast Raptor Management Symposium and Workshop. ","largerWorkSubtype":{"id":4,"text":"Other Government Series"},"language":"English","publisher":"National Wildlife Federation.","usgsCitation":"Smith, D., and Ellis, D.H., 1989, Snowy owl, chap. of Proceedings of the Northeast Raptor Management Symposium and Workshop. , p. 97-105.","productDescription":"xi, 353","startPage":"97","endPage":"105","costCenters":[{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true}],"links":[{"id":200628,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e49f0e4b07f02db5edf32","contributors":{"editors":[{"text":"Pendleton, Beth Giron","contributorId":111970,"corporation":false,"usgs":true,"family":"Pendleton","given":"Beth","email":"","middleInitial":"Giron","affiliations":[],"preferred":false,"id":506523,"contributorType":{"id":2,"text":"Editors"},"rank":1},{"text":"LeFranc, Maurice N.= Jr.","contributorId":113626,"corporation":false,"usgs":true,"family":"LeFranc","given":"Maurice","suffix":"Jr.","email":"","middleInitial":"N.=","affiliations":[],"preferred":false,"id":506524,"contributorType":{"id":2,"text":"Editors"},"rank":2},{"text":"Moss, Mary Beth","contributorId":114080,"corporation":false,"usgs":true,"family":"Moss","given":"Mary","email":"","middleInitial":"Beth","affiliations":[],"preferred":false,"id":506525,"contributorType":{"id":2,"text":"Editors"},"rank":3}],"authors":[{"text":"Smith, D.G.","contributorId":49393,"corporation":false,"usgs":true,"family":"Smith","given":"D.G.","email":"","affiliations":[],"preferred":false,"id":328521,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ellis, D. H.","contributorId":79830,"corporation":false,"usgs":true,"family":"Ellis","given":"D.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":328522,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70015681,"text":"70015681 - 1989 - Variations in fluvial style in the Westwater Canyon Member, Morrison formation (Jurassic), San Juan basin, Colorado plateau","interactions":[],"lastModifiedDate":"2025-07-23T14:54:27.612823","indexId":"70015681","displayToPublicDate":"2003-04-11T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3368,"text":"Sedimentary Geology","active":true,"publicationSubtype":{"id":10}},"title":"Variations in fluvial style in the Westwater Canyon Member, Morrison formation (Jurassic), San Juan basin, Colorado plateau","docAbstract":"Techniques of architectural element analysis and lateral profiling have been applied to the fluvial Westwater Canyon Member of the Morrison Formation (Jurassic) in southern San Juan Basin. On a large scale, the sandstone-body architecture consists mainly of a series of tabular sandstone sheets 5–15 m thick and hundreds of meters wide, separated by thin fine-grained units. Internally these sheets contain lateral accretion surfaces and are cut by channels 10–20 m deep and at least 250 m wide.
On a more detailed scale, interpretations made from large-scale photomosaics show a complex of architectural elements and bounding surfaces. Typical indicators of moderate- to high-sinuosity channels (lateral accretion deposits) coexist in the same outcrop with downstream-accreted macroform deposits that are typical of sand flats of low-sinuosity, multiple-channel rivers. Broad, deep channels with gently to steeply dipping margins were mapped in several of the outcrops by carefully tracing major bounding surfaces. Locally thick accumulations of plane-laminated and low-angle cross-laminated sandstone lithofacies suggest rapid flow, probably transitional to upper flow regime conditions. Such a depositional style is most typical of ephemeral rivers or those periodically undergoing major seasonal (or more erratic) stage fluctuations, an interpretation consistent with independent mineralogical evidence of aridity.
Fining-upward sequences are rare in the project area, contrary to the descriptions of Campbell (1976). The humid alluvial fan model of Galloway (1978) cannot be substantiated and, similarly, the architectural model of Campbell (1976) requires major revision. Comparisons with the depositional architecture of the large Indian rivers, such as the Ganges and Brahmaputra, still seem reasonable, as originally proposed by Campbell (1976), although there is now convincing evidence for aridity and for major stage fluctuations, which differs both from those modern rivers and Campbell's interpretation.
","language":"English","publisher":"Elsevier","doi":"10.1016/0037-0738(89)90070-5","issn":"00370738","usgsCitation":"Miall, A., and Turner-Peterson, C.E., 1989, Variations in fluvial style in the Westwater Canyon Member, Morrison formation (Jurassic), San Juan basin, Colorado plateau: Sedimentary Geology, v. 63, no. 1-2, p. 21-60, https://doi.org/10.1016/0037-0738(89)90070-5.","productDescription":"40 p.","startPage":"21","endPage":"60","costCenters":[],"links":[{"id":223834,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Arizona, Colorado, New Mexico, Utah","otherGeospatial":"San Juan basin","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -111.34773878542157,\n 39.00342263812402\n ],\n [\n -111.34773878542157,\n 35.28734981483113\n ],\n [\n -106.73828172972128,\n 35.28734981483113\n ],\n [\n -106.73828172972128,\n 39.00342263812402\n ],\n [\n -111.34773878542157,\n 39.00342263812402\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"63","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bc17fe4b08c986b32a5e2","contributors":{"authors":[{"text":"Miall, A.D.","contributorId":35879,"corporation":false,"usgs":true,"family":"Miall","given":"A.D.","affiliations":[],"preferred":false,"id":371514,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Turner-Peterson, Christine E.","contributorId":97071,"corporation":false,"usgs":true,"family":"Turner-Peterson","given":"Christine","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":371515,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":38793,"text":"pp560A - 1989 - Geology of the Arabian Peninsula; shield area of western Saudi Arabia","interactions":[{"subject":{"id":8083,"text":"ofr84203 - 1984 - Geology of the Arabian Peninsula shield area of western Saudi Arabia","indexId":"ofr84203","publicationYear":"1984","noYear":false,"title":"Geology of the Arabian Peninsula shield area of western Saudi Arabia"},"predicate":"SUPERSEDED_BY","object":{"id":38793,"text":"pp560A - 1989 - Geology of the Arabian Peninsula; shield area of western Saudi Arabia","indexId":"pp560A","publicationYear":"1989","noYear":false,"chapter":"A","title":"Geology of the Arabian Peninsula; shield area of western Saudi Arabia"},"id":1}],"lastModifiedDate":"2015-09-29T15:43:17","indexId":"pp560A","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":331,"text":"Professional Paper","code":"PP","onlineIssn":"2330-7102","printIssn":"1044-9612","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"560","chapter":"A","title":"Geology of the Arabian Peninsula; shield area of western Saudi Arabia","docAbstract":"Western Arabia lies within the low-latitude desert of north Africa and the Middle East, the core being the Arabian segment of the African Shield. The core of complex basement rocks accounts for about 670,000 km2, or one-third of the Arabian Peninsula. Reconnaissance mapping of these crystalline rocks, together with bordering sedimentary rocks and volcanic flows, begun in 1950, resulted during the next 13 years in a series of geologic and geographic maps without extensive texts. The maps served as general guides for development of natural resources, including water supplies, ore deposits, and building materials. An intensive exploration program that began in 1963 and involved numerous geologists has vastly increased geologic information.
\nRainfall in Arabia is meager and episodic, and vegetation is sparse except in isolated copses on the crest of the Hejaz Range. Comparison of flora with similar species in the Sudan, where records of rainfall have long been kept, allows evaluation of mean annual precipitation. Wandering bedouin following fodder created a delicate balance between population and water supply-now disturbed by wells drilled in alluvium and lava fields.
\nA trapezoidal region of Precambrian crystalline rocks lies along the northeast flank of the Red Sea, with two long prongs extending northwest and southeast for a total of 1,800 km. These basement rocks of the Arabian Shield are well exposed on the uplands, scarp mountains, and coastal pediments where the Phanerozoic cover rocks have been stripped as a result of Paleozoic epeirogeny and Tertiary ramping. The shield outcrops are divided into three tectonic provinces by N. 45°W.- trending shear zones of the Najd fault system of latest Proterozoic and possibly earliest Paleozoic time. The southwestern province, the 'Asir1 upland, was sharply uplifted and tilted to the northeast during the Neogene. The northwestern province, consisting of the Ash Shifa'- Hisma upland as well as Jabal Shammar farther east, similarly was uplifted and tilted. These two provinces are separated by the flat-lying median N ajd province, which is chiefly bounded by the principal Najd faults.
\nThe outcrops of the shield rocks are of the Late Proterozoic Eonupper Riphean to Vendian or Infracambrian epochs, including the Ediacarian System. The most reliable isotopic ages range from about 900 to 560 m.y., but some Middle Proterozoic rocks may be present in the easternmost shield. The rocks are divided into six lithostratigraphic sequences, two plutonic suites, and an ophiolitic suite. The mafic and ultramafic volcanic and plutonic rocks of the ophiolitic suite everywhere were emplaced tectonically and are probably of different ages in different places. Some ophiolite occurs as obducted blocks, but most is highly deformed and altered to serpentinite in fault zones that mostly define sutures between different tectonic blocks or terranes within the shield.
\nThree of the lithostratigraphic sequences consist of mafic to silicic volcanic rocks and volcanic-derived clastic rocks which, with their subvolcanic plutonic rocks of a dioritic suite, probably formed in oceanic island arcs during convergent plate tectonism. These rocks make up the primary, or first-formed, crust of the shield. Chemical analyses show that the primary shield rocks, regardless of age, are principally calc-alkalic with some associated tholeiitic varieties. Most of the layered rocks are andesitic, but they range from basalt to dacite and in places contain intercalated pillow basalt, marble, chert, and carbonaceous or graphitic schist. Most of the plutonic rocks of the dioritic suite are dioritic, but they range from gabbro to trondhjemite and rarely contain potassium feldspar. The sequences and an associated dioritic suite become younger toward the eastern shield, that is, the primary crust of the shield youngs toward the east.
\nTwo western sequences consist of the Jiddah (Samran) and BaishBahah Groups and range in radiometric age from about 900 to 800 m.y.; the eastern sequence consists of the Halaban (Hulayfah) Group and ranges from 800 to about 700 m.y. During subsequent orogeny, most of the rocks were intensely deformed and mostly metamorphosed to upper greenschist facies, but rising in places to the almandine-amphibolite facies.
\nTwo other lithostratigraphic sequences with an associated plutonic granitic suite are the products of two mountain-building episodes during which the primary crust was greatly thickened and converted into craton. The two sequences, including largely the Ablah (Al Ays) and Murdama (Shammar) Groups, consist of abundant sedimentary rocks, commonly arkosic, that are the erosional products of the orogenic mountains. They are several thousand meters thick. Less abundant calc-alkalic to alkalic volcanic rocks, commonly dacitic and rhyolitic, are intercalated with the sedimentary rocks. The plutonic rocks of the granitic suite in association with both sequences have syntectonic and posttectonic phases, are products of the orogenies, and are the principal new ingredients making up the craton.
\nGneiss domes were a significant part of these cratonization orogenies. In association with orogenic crustal heating, some of the low-density, more silicic tonalitic and trondhjemitic rocks of the primary crust rose as gneiss domes. Partial melting in the middle or lower crust below the gneiss domes produced large volumes of granitic magma that intruded the gneiss domes as granodioritic batholiths.
\nThe Ablah Group and the older part of the granitic suite are about 775 to 740 Ma old and are associated with the Ablah orogeny and early cratonization in the western and earlier formed half of the shield. The Murdama (Shammar) Group and the younger part of the granitic suite are about 660 to 580 Ma old and are associated with the culminant orogeny and late cratonization that was shieldwide. The granitic suite during both orogenies consists of early, syntectonic granodiorite batholiths associated with the gneiss domes and late, posttectonic monzogranite plutons. Only during the culminant orogeny, late magmatic evolution produced syenogranite and alkali-feldspar granite commonly in circular and ring-structured plutons and with associated explosive volcanic deposits (Shammar Group); final products, some of which have economic potential, were peralkalic and peraluminous. The late plutonism of the culminant orogeny was distinctly bimodal in that subordinate gabbroic rocks are associated with the granites.
\nVarious building blocks or terranes of the andesitic and dioritic primary crust were collisionally agglomerated during the Ablah orogeny, early cratonization, whereas the entire shield as currently exposed was further collisionally accreted and compressionally consolidated during the culminant orogeny, final cratonization. Thousands of kilometers of oceanic crust had to be subducted in about 300 m.y. to form the large primary crust of the Arabian Shield. The inevitable collisional events during consumption of such a large volume of oceanic crust invariably led to numerous collisional orogenies that collectively encompass the widely known Pan African tectonic episode.
\nThe youngest lithostratigraphic sequence, the Jubaylah Group, is essentially postcratonic, although it is the end product of the collisional culminant orogeny. Final east-west compression of the entire shield from about 580 to 560 m.y. caused the craton to fracture along the large northwest-trending, left-lateral faults and elsewhere along lesser, northeast-trending, right-lateral, conjugate faults of the N ajd fault system. Erosional products of this more localized deformation were the sedimentary rocks of the Jubaylah Group, which also includes intercalated andesitic to basaltic volcanic rocks of a mafic alkalic compositional trend.
\nThe collisional edge of an old continental plate (or tectonic fragments thereof), suspected on the eastern edge of the Arabian Shield, has not been shown with certainty to be exposed. Presumably, widespread contamination from such an old continental crust affects U/Pb, Sm/Nd, Rb/Sr, and common lead ratios in the young plutonic rocks of the easternmost shield. One mass of anorthosite near Jabal Khida' on the central eastern edge of the shield may be a fragment of this old continental plate in that associated granodiorite may be as old as 1,600 to 1,800 Ma.
\nEpeirogenic uplift, erosion, and cooling of the uppermost shield during Early and Middle Cambrian time is indicated by an average fission track age of 510±52 m.y., on sphene from diorite (hornblende K-Ar age of 615±12 m.y.) in the southwestern part of the shield. The hiatus was followed by extensive deposition of the Cambro-Ordovician Saq Sandstone in the north and northeast and the Wajid Sandstone in the southeast and south of the shield. The Cambrian Siq Sandstone had already been deposited in the northern part. During the middle and late Paleozoic, broad epeirogeny caused further erosion of the shield until marine transgression deposited the Upper Permian Khuff Formation at least in the eastern part of the shield. In the southwestern shield, the nonmarine Upper Triassic Khums Sandstone was deposited variably on Wajid or Precambrian rocks and is overlain by limestone of the middle Upper Jurassic Amran Formation.
\nExcept for shallow marine sandstone of problematic Cretaceous age deposited on the Amran Formation in the south.western shield and on Precambrian rocks in the northwestern shield, the younger beds on the shield are Paleocene and younger, with the possibility that the lowermost are upper Maestrichtian. The early Tertiary beds contain vertebrate fossils of coastal marine or estuarine environment 250 km east of the Red Sea in the central shield. Marginal marine sediments were deposited in a western tongue of the latest Tethys Sea as late as Eocene on the western shield and at least as far south as Jiddah.
\nThe great harrats of flood basalt erupted on th~ western shield during late Oligocene and early Miocene at the same time a 2,000-kmlong continental rift valley developed along the future Red Sea axis. Within this rift valley, Baid freshwater tuffaceous lakebeds were deposited between mafic and silicic volcanoes. During late early Miocene time, the Red Sea opened at a rate of 4.4 cm/yr in a firststage movement while continental dikes and swarms of oceanic tholeiitic dikes, gabbro, and granophyre plutonic rocks were intruded into the rift sedimentary and volcanic rocks at the newly formed continental margin. The continental margin was deformed and greatly extended at this time. About 14 or 15 m.y., as the first-stage spreading stopped, the Red Sea Escarpment rose; its erosion caused deposition of coarse conglomerate of the Bathan Formation. About 3,000 m of evaporite was deposited on the young Red Sea oceanic crust during the late Miocene desiccation crisis.
\nA second stage of sea-floor spreading about 4-5 m.y. produced the Red Sea axial trough, consisting of oceanic crust, as well as renewed uplift and tilting of the three tectonic provinces in response to compression from counterclockwise rotation against the Dead Sea Rift. This late movement caused widespread major stream capture, especially along the wadis that formerly drained southwesterly or northwesterly, the channels turning westward through narrow gorges to the coastal plain and the Red Sea.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/pp560A","usgsCitation":"Brown, G., Schmidt, D., and Huffman, A.C., 1989, Geology of the Arabian Peninsula; shield area of western Saudi Arabia: U.S. Geological Survey Professional Paper 560, Report: x, 189 p.; Maps, https://doi.org/10.3133/pp560A.","productDescription":"Report: x, 189 p.; Maps","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":113234,"rank":400,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/pp/0560a/plate-1_north.pdf","size":"11953","linkFileType":{"id":1,"text":"pdf"}},{"id":113233,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/pp/0560a/report.pdf","size":"40789","linkFileType":{"id":1,"text":"pdf"}},{"id":113235,"rank":401,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/pp/0560a/plate-1_south.pdf","size":"16462","linkFileType":{"id":1,"text":"pdf"}},{"id":113236,"rank":402,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/pp/0560a/plate-2_north.pdf","size":"5499","linkFileType":{"id":1,"text":"pdf"}},{"id":113237,"rank":403,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/pp/0560a/plate-2_south.pdf","size":"4466","linkFileType":{"id":1,"text":"pdf"}},{"id":113238,"rank":404,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/pp/0560a/plate-3.pdf","size":"7642","linkFileType":{"id":1,"text":"pdf"}},{"id":113239,"rank":405,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/pp/0560a/plate-4.pdf","size":"2853","linkFileType":{"id":1,"text":"pdf"}},{"id":173512,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/pp/0560a/report-thumb.jpg"}],"country":"Saudi Arabia","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n 34.7607421875,\n 29.611670115197406\n ],\n [\n 38.67187499999999,\n 31.690781806136822\n ],\n [\n 47.98828124999999,\n 23.1201536216956\n ],\n [\n 45.3515625,\n 17.518344187852218\n ],\n [\n 42.2314453125,\n 16.214674588248556\n ],\n [\n 34.365234375,\n 28.14950321154457\n ],\n [\n 34.7607421875,\n 29.611670115197406\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4ad5e4b07f02db68344f","contributors":{"authors":[{"text":"Brown, Glen F.","contributorId":51711,"corporation":false,"usgs":true,"family":"Brown","given":"Glen F.","affiliations":[],"preferred":false,"id":220454,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Schmidt, Dwight L.","contributorId":69568,"corporation":false,"usgs":true,"family":"Schmidt","given":"Dwight L.","affiliations":[],"preferred":false,"id":220453,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Huffman, A. Curtis Jr.","contributorId":50191,"corporation":false,"usgs":true,"family":"Huffman","given":"A.","suffix":"Jr.","email":"","middleInitial":"Curtis","affiliations":[],"preferred":false,"id":220455,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":27270,"text":"wri874195 - 1989 - Hydrogeology of the Leadville limestone and other paleozoic rocks in northwestern Colorado, with results of aquifer tests at Glenwood Springs","interactions":[],"lastModifiedDate":"2012-02-02T00:08:43","indexId":"wri874195","displayToPublicDate":"1994-01-01T00:00:00","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":"87-4195","title":"Hydrogeology of the Leadville limestone and other paleozoic rocks in northwestern Colorado, with results of aquifer tests at Glenwood Springs","docAbstract":"Paleozoic rocks in northwestern Colorado were investigated during the U.S. Geological Survey 's Regional Aquifer Systems Analysis of the Upper Colorado River Basin. Paleozoic rocks in the study area are grouped into 11 hydrostratigraphic units on the basis of lithologic and hydrologic properties. Devonian and Mississippian carbonate rocks and Pennsylvanian and Permian sandstone are regional aquifers, with natural discharges commonly ranging from 50 to 1,000 gal/min. Other hydrostratigraphic units in the area are either local aquifers or confining layers, with discharges rarely exceeding 50 gal/min. Aquifer tests at Glenwood Springs indicate that the Devonian and Mississippian carbonate rocks unit locally has a transmissivity of 47,000 sq ft/day, a storage coefficient of 0.0005, and a hydraulic conductivity of more than 100 ft/day. Hydraulic conductivities in most hydrostratigraphic units decrease with distance away from structural uplifts. Water in the Devonian and Mississippian carbonate rocks unit flows from structural uplifts to structural and fluvial basins. This hydrostratigraphic unit supplies water to streams that drain the White River Plateau, hot springs at Glenwood Springs, and artesian wells in the Burns basin. (USGS)","language":"ENGLISH","publisher":"Dept. of the Interior, U.S. Geological Survey ;\r\nBooks and Open-File Reports [distributor],","doi":"10.3133/wri874195","usgsCitation":"Geldon, A.L., 1989, Hydrogeology of the Leadville limestone and other paleozoic rocks in northwestern Colorado, with results of aquifer tests at Glenwood Springs: U.S. Geological Survey Water-Resources Investigations Report 87-4195, vi, 96 p. :ill., maps ;28 cm., https://doi.org/10.3133/wri874195.","productDescription":"vi, 96 p. :ill., maps ;28 cm.","costCenters":[],"links":[{"id":124127,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1987/4195/report-thumb.jpg"},{"id":56149,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1987/4195/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a2ee4b07f02db6150ba","contributors":{"authors":[{"text":"Geldon, Arthur L.","contributorId":16395,"corporation":false,"usgs":true,"family":"Geldon","given":"Arthur","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":197830,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":26927,"text":"wri864142 - 1989 - Relation between land use and ground-water quality in the upper glacial aquifer in Nassau and Suffolk Counties, Long Island, New York","interactions":[],"lastModifiedDate":"2012-02-02T00:08:34","indexId":"wri864142","displayToPublicDate":"1994-01-01T00:00:00","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":"86-4142","title":"Relation between land use and ground-water quality in the upper glacial aquifer in Nassau and Suffolk Counties, Long Island, New York","docAbstract":"The chemical quality of groundwater in the upper glacial (water-table) aquifer beneath the 10 types of land-use areas of Nassau and Suffolk Counties, NY was examined to evaluate the effect of human activities on groundwater. The highest median chloride and total dissolved-solids concentrations were found in wells in high-density residential areas (more than five dwellings/acre), and the highest median nitrate, sulfate, and calcium concentrations were found in wells in agricultural and high density residential areas. Relatively low median concentrations of inorganic chemical constituents were found in wells in undeveloped and low-density residential areas (1 or fewer/acre): volatile organic compounds were rarely detected in these same areas. The highest concentrations and most frequent detection of volatile organic compounds were in industrial and commercial areas. The most commonly detected volatile organic compounds were 1,1,1-trichloroethane (24% of wells), tetrachloroethylene (20%), trichloroethylene (18%), chloroform (9%), and 1,2-dichloroethylene (5%). The spatial distributions of trichloroethylene, chloroform and other volatile organic compounds in the upper glacial aquifer are directly correlated with population density in the two-county area. (USGS)","language":"ENGLISH","publisher":"U.S. Geological Survey,","doi":"10.3133/wri864142","usgsCitation":"Eckhardt, D., Flipse, W., and Oaksford, E., 1989, Relation between land use and ground-water quality in the upper glacial aquifer in Nassau and Suffolk Counties, Long Island, New York: U.S. Geological Survey Water-Resources Investigations Report 86-4142, v, 35 p. :ill., maps ;28 cm., https://doi.org/10.3133/wri864142.","productDescription":"v, 35 p. :ill., maps ;28 cm.","costCenters":[],"links":[{"id":158290,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1986/4142/report-thumb.jpg"},{"id":55817,"rank":400,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/wri/1986/4142/plate-1.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":55818,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1986/4142/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a60e4b07f02db634d21","contributors":{"authors":[{"text":"Eckhardt, D. A.","contributorId":99591,"corporation":false,"usgs":true,"family":"Eckhardt","given":"D. A.","affiliations":[],"preferred":false,"id":197261,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Flipse, W.J. Jr.","contributorId":98733,"corporation":false,"usgs":true,"family":"Flipse","given":"W.J.","suffix":"Jr.","email":"","affiliations":[],"preferred":false,"id":197260,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Oaksford, E. T.","contributorId":64284,"corporation":false,"usgs":true,"family":"Oaksford","given":"E. T.","affiliations":[],"preferred":false,"id":197259,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":12475,"text":"ofr89146 - 1989 - Minor element content, including radioactive elements and rare-earth elements, in rocks from the syenite complex at Roy Creek, Mount Prindle area, Alaska","interactions":[],"lastModifiedDate":"2012-02-02T00:06:45","indexId":"ofr89146","displayToPublicDate":"1994-01-01T00:00:00","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":"89-146","title":"Minor element content, including radioactive elements and rare-earth elements, in rocks from the syenite complex at Roy Creek, Mount Prindle area, Alaska","language":"ENGLISH","publisher":"U.S. Geological Survey,","doi":"10.3133/ofr89146","usgsCitation":"Armbrustmacher, T.J., 1989, Minor element content, including radioactive elements and rare-earth elements, in rocks from the syenite complex at Roy Creek, Mount Prindle area, Alaska: U.S. Geological Survey Open-File Report 89-146, [i] 11 p. :map ;29 cm., https://doi.org/10.3133/ofr89146.","productDescription":"[i] 11 p. :map ;29 cm.","costCenters":[],"links":[{"id":146440,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/1989/0146/report-thumb.jpg"},{"id":40729,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/1989/0146/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b05e4b07f02db699c9b","contributors":{"authors":[{"text":"Armbrustmacher, Theodore J.","contributorId":31376,"corporation":false,"usgs":true,"family":"Armbrustmacher","given":"Theodore","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":166199,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70123422,"text":"70123422 - 1989 - Acid precipitation studies in Colorado and Wyoming: interim report of surveys of montane amphibians and water chemistry","interactions":[],"lastModifiedDate":"2017-11-21T16:48:52","indexId":"70123422","displayToPublicDate":"1989-06-01T13:16:02","publicationYear":"1989","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":9,"text":"Other Report"},"seriesNumber":"Biological Report 80(40.26)","title":"Acid precipitation studies in Colorado and Wyoming: interim report of surveys of montane amphibians and water chemistry","docAbstract":"Acid deposition may be detrimental or stressful to native populations of wildlife. Because many species of amphibians breed in shallow ponds created by spring rains or melting snow, they may be particularly vulnerable to the effects of acidification. From 1986 to 1988, we surveyed 105 locations in the central Rocky Mountains where amphibians had been recorded previously, and we found that two species of amphibians had experiences major losses. We found the northern leopard frog (Rana pipiens) at only 4 of 33 (12%) historically known localities, and the boreal toad (Bufo boreas) was present at 10 of 59 (17%) known localities. Three other species have not suffered region-wide declines. Tiger salamanders (Ambystoma tigrinum) and wood frogs (Rana sylvatica) were present at 45% and 69% of known localities respectively, and were observed at several localities were they had not been recorded previously. Chorus frogs (Pseudacris triseriata) suffered a catastrophic decline in population size in one population monitored since 1961, but regionally, this species was observed in 36 of 56 (64%) known localities and in another 19 localities where there were no previous records.
\nComplete water chemistry was recorded for 41 localities, and pH was measured at 110 sites in total. Acid neutralizing capacity, pH, specific conductivity, and cation concentrations were negatively correlated with elevation. However, in mountain ponds and lakes, pH was rarely less than 6.0 during the amphibian breeding season.
\nWe tested the tolerance of embryos of the four species of frogs to low pH. The LC50 pH was 4.8 for chorus frogs, 4.4-4.7 for leopard frogs, 4.4-4.5 for boreal toads, and 4.2-4.3 for wood frogs. Survival of wood frog embryos declined when exposed to aluminum concentrations of 100 µg/L or greater, but boreal toad embryos survived exposure to aluminum concentrations of 400 µg/L.
\nAcid deposition does not appear to be a major factor in the decline of leopard frogs and boreal toads. However, we have not yet investigated effects of sublethal pH on growth and development of tadpoles. Pollution remains suspect, but other factors, including natural fluctuations in population size, may account for the observed declines.
","language":"English","publisher":"U.S. Department of the Interior, Fish and Wildlife Service","publisherLocation":"Washington, D.C.","usgsCitation":"Corn, P., Stolzenburg, W., and Bury, R.B., 1989, Acid precipitation studies in Colorado and Wyoming: interim report of surveys of montane amphibians and water chemistry, 56 p.","productDescription":"56 p.","numberOfPages":"56","costCenters":[],"links":[{"id":293403,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Colorado;Wyoming","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -110.99,36.99 ], [ -110.99,44.96 ], [ -102.04,44.96 ], [ -102.04,36.99 ], [ -110.99,36.99 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5409ad34e4b09baad27cdb46","contributors":{"authors":[{"text":"Corn, Paul Stephen 0000-0002-4106-6335","orcid":"https://orcid.org/0000-0002-4106-6335","contributorId":107379,"corporation":false,"usgs":true,"family":"Corn","given":"Paul Stephen","affiliations":[{"id":595,"text":"U.S. Geological Survey","active":false,"usgs":true}],"preferred":false,"id":500110,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Stolzenburg, William","contributorId":60135,"corporation":false,"usgs":true,"family":"Stolzenburg","given":"William","email":"","affiliations":[],"preferred":false,"id":500109,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bury, R. Bruce buryb@usgs.gov","contributorId":3660,"corporation":false,"usgs":true,"family":"Bury","given":"R.","email":"buryb@usgs.gov","middleInitial":"Bruce","affiliations":[{"id":290,"text":"Forest and Rangeland Ecosystem Science Center","active":false,"usgs":true}],"preferred":false,"id":500108,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70015409,"text":"70015409 - 1989 - Geochemical evidence for invasion of Kilauea's plumbing system by Mauna Loa magma","interactions":[],"lastModifiedDate":"2025-06-02T15:55:24.092012","indexId":"70015409","displayToPublicDate":"1989-01-19T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2840,"text":"Nature","active":true,"publicationSubtype":{"id":10}},"title":"Geochemical evidence for invasion of Kilauea's plumbing system by Mauna Loa magma","docAbstract":"From the beginning of the study of Hawaiian volcanism there has been controversy over possible relationships between the neighbouring active volcanoes Mauna Loa and Kilauea1–5. Seismic activity, thought to reflect upward migration of magma, reveals that the magmatic plumbing systems apparently converge at depth to form a broad funnel within the mantle6. Although on rare occasions they have erupted concurrently, the brief historical eruptive record appears to show that when Kilauea is most active, Mauna Loa is in repose and vice versa, suggesting that they may be competing for the same magma supply5,7. Petrological, geochemical and isotope data, however, require a diametrically opposite conclusion. Distinct differences in major-element, trace-element and isotope compositions of lavas are regarded as compelling evidence that the two volcanoes have separate magmatic plumbing systems, supplied by parental magmas from physically and geochemically distinct mantle sources8–13. Here we present preliminary geochemical data which show that in the past 2,000 years Kilauea has erupted a spectrum of lava compositions resembling historical Kilauea lavas at one end and Mauna Loa lavas at the other. We discuss the cause of this diversity, and speculate that magma from Mauna Loa may have invaded Kilauea's 'high-level' magmatic plumbing system.
","language":"English","publisher":"Springer Nature","doi":"10.1038/337257a0","issn":"00280836","usgsCitation":"Rhodes, J., Wenz, K., Neal, C., Sparks, J.W., and Lockwood, J.P., 1989, Geochemical evidence for invasion of Kilauea's plumbing system by Mauna Loa magma: Nature, v. 337, no. 6204, p. 257-260, https://doi.org/10.1038/337257a0.","productDescription":"4 p.","startPage":"257","endPage":"260","costCenters":[],"links":[{"id":224309,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Hawaii","otherGeospatial":"Kilauea. Mauna Loa","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -155.60940742819443,\n 19.530273132496674\n ],\n [\n -155.60940742819443,\n 19.224807673368957\n ],\n [\n -155.155825009142,\n 19.224807673368957\n ],\n [\n -155.155825009142,\n 19.530273132496674\n ],\n [\n -155.60940742819443,\n 19.530273132496674\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"337","issue":"6204","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a162fe4b0c8380cd5509c","contributors":{"authors":[{"text":"Rhodes, J.M.","contributorId":31110,"corporation":false,"usgs":true,"family":"Rhodes","given":"J.M.","affiliations":[],"preferred":false,"id":370872,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wenz, K.P.","contributorId":16167,"corporation":false,"usgs":true,"family":"Wenz","given":"K.P.","email":"","affiliations":[],"preferred":false,"id":370871,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Neal, C.A. 0000-0002-7697-7825","orcid":"https://orcid.org/0000-0002-7697-7825","contributorId":91122,"corporation":false,"usgs":true,"family":"Neal","given":"C.A.","affiliations":[],"preferred":false,"id":370874,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Sparks, J. W.","contributorId":84083,"corporation":false,"usgs":false,"family":"Sparks","given":"J.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":370873,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Lockwood, J. P.","contributorId":104473,"corporation":false,"usgs":true,"family":"Lockwood","given":"J.","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":370875,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70006473,"text":"70006473 - 1989 - Hybridization of ciscoes (Coregonus spp.) in Lake Huron","interactions":[],"lastModifiedDate":"2016-03-21T12:52:37","indexId":"70006473","displayToPublicDate":"1989-01-01T10:45:36","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1176,"text":"Canadian Journal of Zoology","active":true,"publicationSubtype":{"id":10}},"title":"Hybridization of ciscoes (Coregonus spp.) in Lake Huron","docAbstract":"Gill raker number and length were compared for lake herring, Coregonus artedii LeSueur, and bloater, Coregonus hoyi (Gill), collected in 1917, 1956, and 1984-1985 at four locations in western Lake Huron to examine the effects of suspected introgressive hybridization on these distinctive species characters. Gill raker length showed no change from 1917 to 1984-1985, but gill raker number became similar in the two species over that period. Between 1917 and 1984-1985, mean gill raker counts decreased from 48.0 to 45.8 in lake herring, but increased from 41.8 to 43.1 in bloaters. The modal count for both species was 43 in 1984-1985. Intermediate gill raker counts were consistent with the hypothesis of hybridization. Bloater abundance increased greatly in the 1980's, but lake herring remained scarce. Under these circumstances, the rare lake herring would be increasingly likely to encounter abundant ripe bloaters during the overlapping spawning seasons of these species, increasing the probability for hybridization. Basic biological differences between the species, such as lower vulnerability of bloaters to commercial harvest, better survival of bloater fry, or greater fecundity of bloaters, may have contributed to the substantially better success of bloaters. Cisco populations are fragile; only the bloater has ever made a strong and sustained recovery after a severe decline. Hybridization with bloaters may impede the recovery of lake herring in Lake Huron.
","language":"English","publisher":"National Research Council of Canada","publisherLocation":"Ottawa, Canada","doi":"10.1139/z89-241","usgsCitation":"Todd, T.N., and Stedman, R.M., 1989, Hybridization of ciscoes (Coregonus spp.) in Lake Huron: Canadian Journal of Zoology, v. 67, no. 7, p. 1679-1685, https://doi.org/10.1139/z89-241.","productDescription":"8 p.","startPage":"1679","endPage":"1685","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":324,"text":"Great Lakes Science Center","active":true,"usgs":true}],"links":[{"id":289192,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"otherGeospatial":"Lake Huron","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -87.897,41.6134 ], [ -87.897,46.5401 ], [ -79.7915,46.5401 ], [ -79.7915,41.6134 ], [ -87.897,41.6134 ] ] ] } } ] }","volume":"67","issue":"7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53b286f1e4b07b8813a554c1","contributors":{"authors":[{"text":"Todd, Thomas N.","contributorId":42547,"corporation":false,"usgs":true,"family":"Todd","given":"Thomas","email":"","middleInitial":"N.","affiliations":[],"preferred":false,"id":354580,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Stedman, Ralph M.","contributorId":60578,"corporation":false,"usgs":true,"family":"Stedman","given":"Ralph","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":354581,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70015992,"text":"70015992 - 1989 - Pillow basalts of the Angayucham terrane: Oceanic plateau and island crust accreted to the Brooks Range","interactions":[],"lastModifiedDate":"2024-05-29T16:38:13.299479","indexId":"70015992","displayToPublicDate":"1989-01-01T00:00:00","publicationYear":"1989","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":6453,"text":"Journal of Geophysical Research Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"Pillow basalts of the Angayucham terrane: Oceanic plateau and island crust accreted to the Brooks Range","docAbstract":"The Angayucham Mountains (north margin of the Yukon-Koyukuk province) are made up of an imbricate stack of four to eight east-west trending, steeply dipping, fault slabs composed of Paleozoic (Devonian to Mississippean), Middle to Late Triassic, and Early Jurassic oceanic upper crustal rocks (pillow basalt, subordinate diabase, basaltic tuff, and radiolarian chert). Field relations and geochemical characteristics of the basaltic rocks suggest that the fault slabs were derived from an oceanic plateau or island setting and were emplaced onto the Brooks Range continental margin. The basalts are variably metamorphosed to prehnite-pumpellyite and low-greenschist facies. Major element analyses suggest that many are hypersthene-normative olivine tholeiites. Classification based on immobile trace elements confirms the tholeiitic character of most of the basalts but suggests that some had primary compositions transitional to alkali basalt. Although field and petrographic features of the basalts are similar, trace element characteristics allow definition of geographically distinct suites. A central outcrop belt along the crest of the mountains is made up of basalt with relatively flat rare earth element (REE) patterns. This belt is flanked to the north and south by LREE (light rare earth element)-enriched basalts. Radiolarian and conodont ages from interpillow and interlayered chert and limestone indicate that the central belt of basalts is Triassic in age, the southern belt is Jurassic in age, and the northern belt contains a mixture of Paleozoic and Mesozoic ages. Data for most of the basalts cluster in the “within-plate basalt” fields of trace element discriminant diagrams; none have trace-element characteristics of island arc basalt. The Triassic and Jurassic basalts are geochemically most akin to modern oceanic plateau and island basalts. Field evidence also favors an oceanic plateau or island setting. The great composite thickness of pillow basalt probably resulted from obduction faulting, but the lack of fault slabs of gabbro or peridotite suggests that obduction faults did not penetrate below oceanic layer 2, a likely occurrence if layer 2 were anomalously thick, as in the vicinity of an oceanic island. The presence of basaltic tuff interbeds indicates proximity to an explosive basaltic eruptive center. The juxtaposition of submarine basalts of differing chemical affinity and age, adjacent to higher-grade Paleozoic metamorphic rocks of the Brooks Range to the north, may be explained by obduction of internally complex (thickened) oceanic crust formed in an ocean plateau setting. Emplacement and rotation of thrust plates to steep attitudes occurred during accretion of the Brooks Range passive margin, probably beginning in the Late to Middle Jurassic.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB094iB11p15901","issn":"01480227","usgsCitation":"Pallister, J., Budahn, J., and Murchey, B., 1989, Pillow basalts of the Angayucham terrane: Oceanic plateau and island crust accreted to the Brooks Range: Journal of Geophysical Research Solid Earth, v. 94, no. B11, p. 15901-15923, https://doi.org/10.1029/JB094iB11p15901.","productDescription":"23 p.","startPage":"15901","endPage":"15923","costCenters":[],"links":[{"id":222984,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"94","issue":"B11","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"505a7b5ee4b0c8380cd793e0","contributors":{"authors":[{"text":"Pallister, J.S.","contributorId":46534,"corporation":false,"usgs":true,"family":"Pallister","given":"J.S.","email":"","affiliations":[],"preferred":false,"id":372283,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Budahn, J. R. 0000-0001-9794-8882","orcid":"https://orcid.org/0000-0001-9794-8882","contributorId":83914,"corporation":false,"usgs":true,"family":"Budahn","given":"J. R.","affiliations":[],"preferred":false,"id":372284,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Murchey, B.L.","contributorId":93074,"corporation":false,"usgs":true,"family":"Murchey","given":"B.L.","email":"","affiliations":[],"preferred":false,"id":372285,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ]}