{"pageNumber":"1549","pageRowStart":"38700","pageSize":"25","recordCount":40797,"records":[{"id":70012390,"text":"70012390 - 1980 - Implications of regional gravity for state of stress in the earth's crust and upper mantle","interactions":[],"lastModifiedDate":"2024-07-16T16:32:20.739665","indexId":"70012390","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","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":"Implications of regional gravity for state of stress in the earth's crust and upper mantle","docAbstract":"<p><span>Topography is maintained by stress differences within the earth. Depending on the distribution of the stress we classify the support as either local or regional compensation. In general, the stresses implied in a regional compensation scheme are an order of magnitude larger than those corresponding to local isostasy. Gravity anomalies, a measure of the earth's departure from hydrostatic equilibrium, can be used to distinguish between the two compensation mechanisms and thus to estimate the magnitude of deviatoric stress in the crust and upper mantle. Topography created at an oceanic ridge crest or in a major continental orogenic zone appears to be locally compensated. Such features were formed on weak crust incapable of maintaining stress differences much greater than the stress from the applied load. Oceanic volcanoes formed on an already cooled, thickened lithosphere are regionally supported with elastic stresses. Similarly, the broad topographic rise seaward of subduction zones is elastically supported as the lithosphere is bent near the plate margin. Although the implied stress is to some degree dependent on the rheological model assumed, the gravity anomalies and surface deformation produced by these features demonstrate that the upper 30–40 km of the oceanic lithosphere is capable of regionally supporting stress differences in the 100-MPa range. Given certain conditions of load emplacement, continental crust can also support loads regionally over 100-m.y. time scales, but the effects of erosion only allow an estimate of a lower bound on stress. Data from space probes indicate that the upper layers of other terrestrial planets also support topographic-induced stress differences in excess of 100 MPa.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB085iB11p06377","issn":"01480227","usgsCitation":"McNutt, M., 1980, Implications of regional gravity for state of stress in the earth's crust and upper mantle: Journal of Geophysical Research Solid Earth, v. 85, no. B11, p. 6377-6396, https://doi.org/10.1029/JB085iB11p06377.","productDescription":"20 p.","startPage":"6377","endPage":"6396","numberOfPages":"20","costCenters":[],"links":[{"id":222473,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"85","issue":"B11","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"505a3929e4b0c8380cd61811","contributors":{"authors":[{"text":"McNutt, M.","contributorId":64805,"corporation":false,"usgs":true,"family":"McNutt","given":"M.","email":"","affiliations":[],"preferred":false,"id":363431,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70012387,"text":"70012387 - 1980 - Heat flow and energetics of the San Andreas fault zone","interactions":[],"lastModifiedDate":"2024-07-16T16:35:20.182875","indexId":"70012387","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","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":"Heat flow and energetics of the San Andreas fault zone","docAbstract":"<p><span>Approximately 100 heat flow measurements in the San Andreas fault zone indicate (1) there is no evidence for local factional heating of the main fault trace at any latitude over a 1000-km length from Cape Mendocino to San Bernardino, (2) average heat flow is high (∼2 HFU, ∼80 mW m</span><sup>−2</sup><span>) throughout the 550-km segment of the Coast Ranges that encloses the San Andreas fault zone in central California; this broad anomaly falls off rapidly toward the Great Valley to the east, and over a 200-km distance toward the Mendocino Triple Junction to the northwest. As others have pointed out, a local conductive heat flow anomaly would be detectable unless the frictional resistance allocated to heat production on the main trace were ≲100 bars. Frictional work allocated to surface energy of new fractures is probably unimportant, and hydrologic convection is not likely to invalidate the conduction assumption, since the heat discharge by thermal springs near the fault is negligible. Explanations for the low dynamic friction fall into two intergradational classes: those in which the fault is weak all of the time and those in which it is weak only during earthquakes (possibly just large ones). The first class includes faults containing anomalously weak gouge materials and faults containing materials with normal frictional properties under near-lithostatic steady state fluid pressures. In the second class, weakening is caused by the event (for example, a thermally induced increase in fluid pressure, dehydration of clay minerals, or acoustic fluidization). In this class, unlike the first, the average strength and ambient tectonic shear stress may be large, ∼1 kbar, but the stress allocated to elastic radiation (the apparent stress) must be of similar magnitude, an apparent contradiction with seismic estimates. Unless seismic radiation is underestimated for large earthquakes, it is difficult to justify average tectonic stresses on the main trace of the San Andreas fault in excess of ∼200 bars. The development of the broad Coast Range heat flow anomaly southward from Cape Mendocino suggests that heat flow increases by a factor of 2 within 4 m.y. after the passage of the Mendocino Triple Junction. This passage leaves the San Andreas transform fault zone in its wake; the depth of the anomalous sources cannot be much greater than the depth of the seismogenic layer. Some of the anomalous heat may be supplied by conduction from the warmer mantle that must occur south of the Mendocino transform (where there is no subducting slab), and some might be supplied by shear heating in the fault zone. With no contribution from shear heating, extreme mantle upwelling would be required, and asthenosphere conditions should exist today at depths of only ∼20 km in the northernmost Coast Ranges. If there is an appreciable contribution from shear heating, the heat flow constraint implies that the seismogenic layer is partially decoupled at its base and that the basal traction is in the sense that resists right lateral motion on the fault(s). As a result of these basal tractions, the average shearing stress in the seismogenic layer would increase with distance from the main fault, and the seismogenic layer would offer substantial resistance to plate motion even though resistance on the main fault might be negligible. These speculative models have testable consequences.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB085iB11p06185","issn":"01480227","usgsCitation":"Lachenbruch, A., and Sass, J., 1980, Heat flow and energetics of the San Andreas fault zone: Journal of Geophysical Research Solid Earth, v. 85, no. B11, p. 6185-6223, https://doi.org/10.1029/JB085iB11p06185.","productDescription":"39 p.","startPage":"6185","endPage":"6223","numberOfPages":"39","costCenters":[],"links":[{"id":222413,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"85","issue":"B11","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"505a2ff7e4b0c8380cd5d26e","contributors":{"authors":[{"text":"Lachenbruch, A.H.","contributorId":76737,"corporation":false,"usgs":true,"family":"Lachenbruch","given":"A.H.","affiliations":[],"preferred":false,"id":363427,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sass, J.H.","contributorId":70749,"corporation":false,"usgs":true,"family":"Sass","given":"J.H.","email":"","affiliations":[{"id":595,"text":"U.S. Geological Survey","active":false,"usgs":true}],"preferred":false,"id":363426,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70012382,"text":"70012382 - 1980 - Mixing models and ionic geothermometers applied to warm (up to 60°C) springs: Jordan Rift Valley, Israel","interactions":[],"lastModifiedDate":"2015-06-12T16:11:44","indexId":"70012382","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2342,"text":"Journal of Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Mixing models and ionic geothermometers applied to warm (up to 60°C) springs: Jordan Rift Valley, Israel","docAbstract":"<p id=\"\">Mixing models and evaluation of SiO<sub>2</sub>&nbsp;contents of warm-water manifestations in the Jordan&mdash;Dead Sea Rift Valley indicate that these waters are fed by aquifers with estimated temperatures of up to 68&deg;C. These calculations and Na/K ratios, concentrations of Na, K and Ca, concentrations of atmospheric Ne, Ar, Kr and Xe; and concentrations of the stable hydrogen and oxygen isotopes all indicate below-boiling temperatures.</p>\n<p id=\"\">No indications are available for the existence of above-boiling geothermal systems in the Jordan Rift Valley. Slightly higher than observed temperatures are concluded for a deep component at the springs of Hammat Gader (67&deg;C), Gofra (68&deg;C), the Russian Garden (40&deg;C), and the Yesha well (53&ndash;65&deg;C). These temperatures may encourage further developments for spas and bathing installations and, to a limited extent, for space heating, but are not favorable for geothermal power generation.</p>","language":"English","publisher":"Elsevier","doi":"10.1016/0022-1694(80)90002-5","issn":"00221694","usgsCitation":"Mazor, E., Levitte, D., Truesdell, A., Healy, J., and Nissenbaum, A., 1980, Mixing models and ionic geothermometers applied to warm (up to 60°C) springs: Jordan Rift Valley, Israel: Journal of Hydrology, v. 45, no. 1-2, p. 1-19, https://doi.org/10.1016/0022-1694(80)90002-5.","productDescription":"19 p.","startPage":"1","endPage":"19","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":222350,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"45","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5b86e4b0c8380cd6f5fb","contributors":{"authors":[{"text":"Mazor, E.","contributorId":18104,"corporation":false,"usgs":true,"family":"Mazor","given":"E.","email":"","affiliations":[],"preferred":false,"id":363416,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Levitte, D.","contributorId":102630,"corporation":false,"usgs":true,"family":"Levitte","given":"D.","email":"","affiliations":[],"preferred":false,"id":363419,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Truesdell, A.H.","contributorId":52566,"corporation":false,"usgs":false,"family":"Truesdell","given":"A.H.","email":"","affiliations":[{"id":6672,"text":"former: USGS Southwest Biological Science Center, Colorado Plateau Research Station, Flagstaff, AZ. Current address:  TN-SCORE, Univ of Tennessee, Knoxville, TN, e-mail: jennen@gmail.com","active":true,"usgs":false}],"preferred":false,"id":363417,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Healy, J.","contributorId":80822,"corporation":false,"usgs":true,"family":"Healy","given":"J.","affiliations":[],"preferred":false,"id":363418,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Nissenbaum, A.","contributorId":103008,"corporation":false,"usgs":true,"family":"Nissenbaum","given":"A.","email":"","affiliations":[],"preferred":false,"id":363420,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}}
,{"id":70012379,"text":"70012379 - 1980 - Sedimentary and structural patterns on the northern Santa Rosa-Cortes Ridge, southern California","interactions":[],"lastModifiedDate":"2024-10-11T15:23:09.867362","indexId":"70012379","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","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":"Sedimentary and structural patterns on the northern Santa Rosa-Cortes Ridge, southern California","docAbstract":"<p><span>The Santa Rosa-Cortes Ridge is an 1800 m high, 180 km long feature lying approximately 90 km off the coast of southern California and directly south of the northern group of Channel Islands. Geophysical profiling and sampling cruises to the northern part of the ridge, an area of recent and future lease sales for petroleum development, provide a strong data base for interpretation of structural and sedimentary patterns and their relation to potential geologic hazards. The northern part of the ridge is a complexly folded and faulted northwest-trending anticlinorium composed mostly of lower and middle Miocene shale and mudstone. Erosional remnants of upper Miocene and Pliocene rocks unconformably overlie highly folded pre-upper Miocene strata. The major structure of the ridge developed almost continuously from Oligocene or early Miocene time to the end of the Tertiary; many small folds formed between post-late Miocene and pre-late Pleistocene time. Numerous small faults cut the rocks on the ridge top. Faults cut basement rocks on the west side of the ridge along the Ferrelo fault zone. Published data on historical epicenters and evidence of offsets on the seafloor from seismic reflection and side-scan profiles, including limited evidence of possible strike-slip movement along fault traces, indicate that the northern Santa Rosa-Cortes Ridge is tectonically active.</span></p><p><span>The crest of the ridge was truncated as the result of repeated sea-level fluctuations in the Quaternary. A thin veneer of unconsolidated medium to fine sand, less than 3 m thick, mantles most of the ridge; locally in topographically low areas and on the upper flanks of the ridge, thickness exceeds 20 m. The meager sediment cover, coupled with available evidence of relatively strong currents flowing across the ridge top, indicate that the ridge is an area of nondeposition or winnowing of fine sediments. Modern sediments become thicker and finer-grained from the ridge top to the ridge flanks, suggesting active accretion in those areas. Slumps are present at various depths on the flanks, and it seems probable that the thicker deposits (&gt; 20 m) of modern sediments on the upper flanks will be sites of future slumping.</span></p>","language":"English","publisher":"Elsevier","doi":"10.1016/0025-3227(80)90142-5","usgsCitation":"Field, M.E., and Richmond, W.C., 1980, Sedimentary and structural patterns on the northern Santa Rosa-Cortes Ridge, southern California: Marine Geology, v. 34, no. 1-2, p. 79-98, https://doi.org/10.1016/0025-3227(80)90142-5.","productDescription":"20 p.","startPage":"79","endPage":"98","costCenters":[],"links":[{"id":222347,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","otherGeospatial":"Santa Rosa-Cortes Ridge, southern California","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"coordinates\": [\n          [\n            [\n              -122.2161864043544,\n              36.94578879902926\n            ],\n            [\n              -122.2161864043544,\n              32.5375086448024\n            ],\n            [\n              -114.39714860847357,\n              32.5375086448024\n            ],\n            [\n              -114.39714860847357,\n              36.94578879902926\n            ],\n            [\n              -122.2161864043544,\n              36.94578879902926\n            ]\n          ]\n        ],\n        \"type\": \"Polygon\"\n      }\n    }\n  ]\n}","volume":"34","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8a11e4b08c986b316ff9","contributors":{"authors":[{"text":"Field, Michael E. mfield@usgs.gov","contributorId":2101,"corporation":false,"usgs":true,"family":"Field","given":"Michael","email":"mfield@usgs.gov","middleInitial":"E.","affiliations":[{"id":520,"text":"Pacific Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":true,"id":363412,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Richmond, William C.","contributorId":85585,"corporation":false,"usgs":true,"family":"Richmond","given":"William","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":363413,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70012374,"text":"70012374 - 1980 - Nd-isotopes in selected mantle-derived rocks and minerals and their implications for mantle evolution","interactions":[],"lastModifiedDate":"2012-03-12T17:19:02","indexId":"70012374","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1336,"text":"Contributions to Mineralogy and Petrology","active":true,"publicationSubtype":{"id":10}},"title":"Nd-isotopes in selected mantle-derived rocks and minerals and their implications for mantle evolution","docAbstract":"The Sm-Nd systematics in a variety of mantle-derived samples including kimberlites, alnoite, carbonatite, pyroxene and amphibole inclusions in alkali basalts and xenolithic eclogites, granulites and a pyroxene megacryst in kimberlites are reported. The additional data on kimberlites strengthen our earlier conclusion that kimberlites are derived from a relatively undifferentiated chondritic mantle source. This conclusion is based on the observation that the e{open}Nd values of most of the kimberlites are near zero. In contrast with the kimberlites, their garnet lherzolite inclusions show both time-averaged Nd enrichment and depletion with respect to Sm. Separated clinopyroxenes in eclogite xenoliths from the Roberts Victor kimberlite pipe show both positive and negative e{open}Nd values suggesting different genetic history. A whole rock lower crustal scapolite granulite xenolith from the Matsoku kimberlite pipe shows a negative e{open}Nd value of -4.2, possibly representative of the base of the crust in Lesotho. It appears that all inclusions, mafic and ultramafic, in kimberlites are unrelated to their kimberlite host. The above data and additional Sm-Nd data on xenoliths in alkali basalts, alpine peridotite and alnoite-carbonatites are used to construct a model for the upper 200 km of the earth's mantle - both oceanic and continental. The essential feature of this model is the increasing degree of fertility of the mantle with depth. The kimberlite's source at depths below 200 km in the subcontinental mantle is the most primitive in this model, and this primitive layer is also extended to the suboceanic mantle. However, it is clear from the Nd-isotopic data in the xenoliths of the continental kimberlites that above 200 km the continental mantle is distinctly different from their suboceanic counterpart. ?? 1980 Springer-Verlag.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Contributions to Mineralogy and Petrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisherLocation":"Springer-Verlag","doi":"10.1007/BF00371888","issn":"00107999","usgsCitation":"Basu, A.R., and Tatsumoto, M., 1980, Nd-isotopes in selected mantle-derived rocks and minerals and their implications for mantle evolution: Contributions to Mineralogy and Petrology, v. 75, no. 1, p. 43-54, https://doi.org/10.1007/BF00371888.","startPage":"43","endPage":"54","numberOfPages":"12","costCenters":[],"links":[{"id":205215,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF00371888"},{"id":222252,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"75","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a63c6e4b0c8380cd726ac","contributors":{"authors":[{"text":"Basu, A. R.","contributorId":99697,"corporation":false,"usgs":true,"family":"Basu","given":"A.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":363404,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Tatsumoto, M.","contributorId":76798,"corporation":false,"usgs":true,"family":"Tatsumoto","given":"M.","email":"","affiliations":[],"preferred":false,"id":363403,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70012368,"text":"70012368 - 1980 - Clarification of the Hashin-Shtrikman bounds on the effective elastic moduli of polycrystals with hexagonal, trigonal, and tetragonal symmetries","interactions":[],"lastModifiedDate":"2012-03-12T17:19:03","indexId":"70012368","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2171,"text":"Journal of Applied Physics","active":true,"publicationSubtype":{"id":10}},"title":"Clarification of the Hashin-Shtrikman bounds on the effective elastic moduli of polycrystals with hexagonal, trigonal, and tetragonal symmetries","docAbstract":"Bounds on the effective elastic moduli of randomly oriented aggregates of hexagonal, trigonal, and tetragonal crystals are derived using the variational principles of Hashin and Shtrikman. The bounds are considerably narrower than the widely used Voigt and Reuss bounds. The Voigt-Reuss-Hill average lies within the Hashin-Shtrikman bounds in nearly all cases. Previous bounds of Peselnick and Meister are shown to be special cases of the present results.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Applied Physics","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1063/1.327804","issn":"00214922","usgsCitation":"Watt, J., and Peselnick, L., 1980, Clarification of the Hashin-Shtrikman bounds on the effective elastic moduli of polycrystals with hexagonal, trigonal, and tetragonal symmetries: Journal of Applied Physics, v. 51, no. 3, p. 1525-1531, https://doi.org/10.1063/1.327804.","startPage":"1525","endPage":"1531","numberOfPages":"7","costCenters":[],"links":[{"id":205209,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1063/1.327804"},{"id":222197,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"51","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f614e4b0c8380cd4c5a1","contributors":{"authors":[{"text":"Watt, J.P.","contributorId":42355,"corporation":false,"usgs":true,"family":"Watt","given":"J.P.","email":"","affiliations":[],"preferred":false,"id":363390,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Peselnick, L.","contributorId":66825,"corporation":false,"usgs":true,"family":"Peselnick","given":"L.","affiliations":[],"preferred":false,"id":363391,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70012363,"text":"70012363 - 1980 - Tectonic state: its significance and characterization in the assessment of seismic effects associated with reservoir impounding","interactions":[],"lastModifiedDate":"2023-12-16T13:51:03.735595","indexId":"70012363","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1517,"text":"Engineering Geology","active":true,"publicationSubtype":{"id":10}},"title":"Tectonic state: its significance and characterization in the assessment of seismic effects associated with reservoir impounding","docAbstract":"<p>Any analysis of seismicity associated with the filling of large reservoirs requires an evaluation of the natural tectonic state in order to determine whether impoundment is the basic source, a mechanically unrelated companion feature, or a triggering stimulus of the observed seismicity. Several arguments indicate that the associated seismicity is usually a triggered effect. Among the elements of tectonic state considered here (existing fractures, accumulated elastic strain, and deformational style), deformational style is especially critical in forecasting the occurrence of impoundment-induced seismicity. The observational evidence indicates that seismicity associated with impounding generally occurs in areas that combine steeply dipping faults, relatively high strain rates, and either extensional or horizontal-shear strain. Simple physical arguments suggest: (1) that increased fluid pressures resulting from increased reservoir head should enhance the likelihood of seismic activity, whatever the tectonic environment; (2) that stress changes resulting from surface loading may increase the likelihood of crustal failure in areas of normal and transcurrent faulting, whereas they generally inhibit failure in areas of thrust faulting. Comparisons with other earthquake-producing artificial and natural processes (underground explosions, fluid injection, underground mining, fluid extraction, volcanic emissions) indicate that reservoir loading may similarly modify the natural tectonic state. Subsurface loading resulting from fluid extraction may be a particularly close analogue of reservoir loading; \"seismotectonic\" events associated with fluid extraction have been recognized in both seismically active and otherwise aseismic regions. Because the historic record of seismicity and surface faulting commonly is short in comparison with recurrence intervals of earthquake and fault-slip events, tectonic state is most reliably appraised through combined studies of historic seismicity and faulting, instrumentally measured strain, and the geological record, especially that of the Quaternary. Experience in California and elsewhere demonstrates that the character and activity of recognized faults can be assessed by means of: instrumental earthquake investigations, repeated geodetic measurements, written history, archeological studies, fault topography, and local stratigraphic relations. Where faults are less easily distinguished, appraisals of tectonic state may be based on both the regional seismicity and the regional history of vertical movement as shown by: repeated levelling and sea-level measurements, written history, archeologic investigations, terrace and shoreline deformation, and denudation and sedimentation studies.</p>","language":"English","publisher":"Elsevier","doi":"10.1016/0013-7952(80)90029-0","issn":"00137952","usgsCitation":"Castle, R.O., Clark, M.M., Grantz, A., and Savage, J., 1980, Tectonic state: its significance and characterization in the assessment of seismic effects associated with reservoir impounding: Engineering Geology, v. 15, no. 1-2, p. 53-99, https://doi.org/10.1016/0013-7952(80)90029-0.","productDescription":"47 p.","startPage":"53","endPage":"99","numberOfPages":"47","costCenters":[],"links":[{"id":222134,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"15","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505ba47ee4b08c986b32039b","contributors":{"authors":[{"text":"Castle, R. O.","contributorId":79880,"corporation":false,"usgs":true,"family":"Castle","given":"R.","email":"","middleInitial":"O.","affiliations":[],"preferred":false,"id":363377,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Clark, M. M.","contributorId":41877,"corporation":false,"usgs":true,"family":"Clark","given":"M.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":363375,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Grantz, A.","contributorId":60378,"corporation":false,"usgs":true,"family":"Grantz","given":"A.","email":"","affiliations":[],"preferred":false,"id":363376,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Savage, J.C. 0000-0002-5114-7673","orcid":"https://orcid.org/0000-0002-5114-7673","contributorId":102876,"corporation":false,"usgs":true,"family":"Savage","given":"J.C.","affiliations":[],"preferred":false,"id":363378,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70012355,"text":"70012355 - 1980 - Nearshore current pattern off south Texas: an interpretation from aerial photographs.","interactions":[],"lastModifiedDate":"2012-03-12T17:19:07","indexId":"70012355","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3254,"text":"Remote Sensing of Environment","printIssn":"0034-4257","active":true,"publicationSubtype":{"id":10}},"title":"Nearshore current pattern off south Texas: an interpretation from aerial photographs.","docAbstract":"Current patterns in a 4-km-wide zone along the south Texas coast were interpreted from patterns of water turbidity visible in aerial photographs taken during a winter day of moderate northerly winds. Features of the turbidity pattern remained recognizable on photographs taken 25 min apart. Currents measured from the movements of these features were southward and nearly parallel to shore, increasing from about 17 cm/sec in an offshore zone to about 40 cm/sec at the line of breaking waves. - from Authors","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Remote Sensing of Environment","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/0034-4257(80)90010-3","issn":"00344257","usgsCitation":"Hunter, R.E., and Hill, G.W., 1980, Nearshore current pattern off south Texas: an interpretation from aerial photographs.: Remote Sensing of Environment, v. 10, no. 2, p. 115-134, https://doi.org/10.1016/0034-4257(80)90010-3.","startPage":"115","endPage":"134","numberOfPages":"20","costCenters":[],"links":[{"id":205170,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0034-4257(80)90010-3"},{"id":221945,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"10","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a6414e4b0c8380cd7287b","contributors":{"authors":[{"text":"Hunter, R. E.","contributorId":48148,"corporation":false,"usgs":true,"family":"Hunter","given":"R.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":363349,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hill, G. W.","contributorId":85551,"corporation":false,"usgs":true,"family":"Hill","given":"G.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":363350,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70012352,"text":"70012352 - 1980 - Scaling variables and interpretation of eigenvalues in principal component analysis of geologic data","interactions":[],"lastModifiedDate":"2012-03-12T17:19:07","indexId":"70012352","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2554,"text":"Journal of the International Association for Mathematical Geology","active":true,"publicationSubtype":{"id":10}},"title":"Scaling variables and interpretation of eigenvalues in principal component analysis of geologic data","docAbstract":"The dominant feature distinguishing one method of principal components analysis from another is the manner in which the original data are transformed prior to the other computations. The only other distinguishing feature of any importance is whether the eigenvectors of the inner product-moment of the transformed data matrix are taken directly as the Q-mode scores or scaled by the square roots of their associated eigenvalues and called the R-mode loadings. If the eigenvectors are extracted from the product-moment correlation matrix, the variables, in effect, were transformed by column standardization (zero means and unit variances), and the sum of the p-largest eigenvalues divided by the sum of all the eigenvalues indicates the degree to which a model containing p components will account for the total variance in the original data. However, if the data were transformed in any manner other than column standardization, the eigenvalues cannot be used in this manner, but can only be used to determine the degree to which the model will account for the transformed data. Regardless of the type of principal components analysis that is performed-even whether it is R or Q-mode-the goodness-of-fit of the model to the original data is given better by the eigenvalues of the correlation matrix than by those of the matrix that was actually factored. ?? 1980 Plenum Publishing Corporation.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of the International Association for Mathematical Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisherLocation":"Kluwer Academic Publishers-Plenum Publishers","doi":"10.1007/BF01034742","issn":"00205958","usgsCitation":"Miesch, A., 1980, Scaling variables and interpretation of eigenvalues in principal component analysis of geologic data: Journal of the International Association for Mathematical Geology, v. 12, no. 6, p. 523-538, https://doi.org/10.1007/BF01034742.","startPage":"523","endPage":"538","numberOfPages":"16","costCenters":[],"links":[{"id":205169,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF01034742"},{"id":221942,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"12","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b871de4b08c986b316308","contributors":{"authors":[{"text":"Miesch, A.T.","contributorId":88726,"corporation":false,"usgs":true,"family":"Miesch","given":"A.T.","affiliations":[],"preferred":false,"id":363343,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70012347,"text":"70012347 - 1980 - Stable carbon isotopes of HCO3- in oil-field waters-implications for the origin of CO2","interactions":[],"lastModifiedDate":"2024-03-14T15:53:42.823553","indexId":"70012347","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1759,"text":"Geochimica et Cosmochimica Acta","active":true,"publicationSubtype":{"id":10}},"title":"Stable carbon isotopes of HCO3- in oil-field waters-implications for the origin of CO2","docAbstract":"<div id=\"preview-section-abstract\"><div id=\"abstracts\" class=\"Abstracts u-font-serif text-s\"><div id=\"aep-abstract-id4\" class=\"abstract author\"><div id=\"aep-abstract-sec-id5\"><p>The δ<sup>13</sup>C values of dissolved HCO<sub>3</sub><sup>−</sup><span>&nbsp;</span>in 75 water samples from 15 oil and gas fields (San Joaquin Valley, Calif., and the Houston-Galveston and Corpus Christi areas of Texas) were determined to study the sources of CO<sub>2</sub><span>&nbsp;</span>of the dissolved species and carbonate cements that modify the porosity and permeability of many petroleum reservoir rocks. The reservoir rocks are sandstones which range in age from Eocene through Miocene. The δ<sup>13</sup>C values of total HCO<sub>3</sub><sup>−</sup><span>&nbsp;</span>indicate that the carbon in the dissolved carbonate species and carbonate cements is mainly of organic origin.</p><p>The range of δ<sup>13</sup>C values for the HCO<sub>3</sub><sup>−</sup><span>&nbsp;</span>of these waters is −20–28 per mil relative to PDB. This wide range of δ<sup>13</sup>C values is explained by three mechanisms. Microbiological degradation of organic matter appears to be the dominant process controlling the extremely low and high δ<sup>13</sup>C values of HCO<sub>3</sub><sup>−</sup><span>&nbsp;</span>in the shallow production zones where the subsurface temperatures are less than 80°C. The extremely low δ<sup>13</sup>C values (&lt; −10 per mil) are obtained in waters where concentrations of SO<sub>4</sub><sup>2−</sup><span>&nbsp;</span>are more than 25 mg/l and probably result from the degradation of organic acid anions by sulfate-reducing bacteria (<i>SO</i><sub>4</sub><sup>2−</sup><span>&nbsp;</span>+<span>&nbsp;</span><i>CH</i><sub>3</sub><i>COO</i><sup>−</sup><span>&nbsp;</span>→ 2<i>HCO</i><sub>3</sub><sup>−</sup><span>&nbsp;</span>+<span>&nbsp;</span><i>HS</i><sup>−</sup>). The high δ<sup>13</sup>C values probably result from the degradation of these anions by methanogenic bacteria (<i>CH</i><sub>3</sub><i>COO</i><sup>−</sup><span>&nbsp;</span>+<span>&nbsp;</span><i>H</i><sub>2</sub><i>O</i><i>ai</i><i>HCO</i><sub>3</sub><sup>−</sup><span>&nbsp;</span>+<span>&nbsp;</span><i>CH</i><sub>4</sub>).</p><p>Thermal decarboxylation of short-chain aliphatic acid anions (principally acetate) to produce CO<sub>2</sub><span>&nbsp;</span>and CH<sub>4</sub><span>&nbsp;</span>is probably the major source of CO<sub>2</sub><span>&nbsp;</span>for production zones with subsurface temperatures greater than 80°C. The δ<sup>13</sup>C values of HCO<sub>3</sub><sup>−</sup><span>&nbsp;</span>for waters from zones with temperatures greater than 100°C result from isotopic equilibration between CO<sub>2</sub><span>&nbsp;</span>and CH<sub>4</sub>. At these high temperatures, δ<sup>13</sup>C values of HCO<sub>3</sub><sup>−</sup><span>&nbsp;</span>decrease with increasing temperatures and decreasing concentrations of these acid anions.</p></div></div></div></div><div id=\"preview-section-introduction\"><br></div><div id=\"preview-section-snippets\"><br></div><div id=\"preview-section-references\"><br></div>","language":"English","publisher":"Elsevier","doi":"10.1016/0016-7037(80)90140-4","issn":"00167037","usgsCitation":"Carothers, W., and Kharaka, Y., 1980, Stable carbon isotopes of HCO3- in oil-field waters-implications for the origin of CO2: Geochimica et Cosmochimica Acta, v. 44, no. 2, p. 323-332, https://doi.org/10.1016/0016-7037(80)90140-4.","productDescription":"10 p.","startPage":"323","endPage":"332","numberOfPages":"10","costCenters":[],"links":[{"id":221886,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"44","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b9665e4b08c986b31b4a3","contributors":{"authors":[{"text":"Carothers, W.W.","contributorId":43803,"corporation":false,"usgs":true,"family":"Carothers","given":"W.W.","email":"","affiliations":[],"preferred":false,"id":363334,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kharaka, Y.K.","contributorId":23568,"corporation":false,"usgs":true,"family":"Kharaka","given":"Y.K.","email":"","affiliations":[],"preferred":false,"id":363333,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70012336,"text":"70012336 - 1980 - Lithospheric loading by the 1896 Riku-u earthquake, northern Japan: Implications for plate flexure and asthenospheric rheology","interactions":[],"lastModifiedDate":"2024-07-16T16:55:17.414077","indexId":"70012336","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","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":"Lithospheric loading by the 1896 Riku-u earthquake, northern Japan: Implications for plate flexure and asthenospheric rheology","docAbstract":"<p><span>Under favorable circumstances the time-dependent aseismic deformation resulting from the loading of the lithosphere by the stress drop of large dip slip earthquakes can be used to determine both the effective elastic plate thickness and the asthenospheric viscosity. The deformation has several similarities with the deflection of the lithosphere by surface loads and with movements due to postglacial rebound. Level changes obtained in the 80 years since the&nbsp;</span><i>M</i><span>&nbsp;= 7.5, 1896 Riku-u earthquake, an intraplate thrust event in northern Honshu, provide convincing evidence that asthenospheric readjustments are responsible for the observed movements. Leveling surveys crossing the zone of surface faulting have been repeated five times since 1900 and delineate a localized depression that has subsided at a continually decreasing rate. The depression is centered close to the 1896 faulting, and its shape and width, about 75 km, are matched by our model using a plate thickness of 30 km. The decaying subsidence rate constrains the viscosity of the uppermost asthenosphere to be 1×10</span><sup>20</sup><span>&nbsp;P. A linear viscous rheology matches the observed decay quite well, although measurements are sparse during the several decades following the earthquake.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB085iB11p06429","issn":"01480227","usgsCitation":"Thatcher, W., Matsuda, T., Kato, T., and Rundle, J.B., 1980, Lithospheric loading by the 1896 Riku-u earthquake, northern Japan: Implications for plate flexure and asthenospheric rheology: Journal of Geophysical Research Solid Earth, v. 85, no. B11, p. 6429-6435, https://doi.org/10.1029/JB085iB11p06429.","productDescription":"7 p.","startPage":"6429","endPage":"6435","numberOfPages":"7","costCenters":[],"links":[{"id":222195,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"85","issue":"B11","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"505a489fe4b0c8380cd67fcb","contributors":{"authors":[{"text":"Thatcher, W.","contributorId":32669,"corporation":false,"usgs":true,"family":"Thatcher","given":"W.","email":"","affiliations":[],"preferred":false,"id":363311,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Matsuda, T.","contributorId":49522,"corporation":false,"usgs":true,"family":"Matsuda","given":"T.","email":"","affiliations":[],"preferred":false,"id":363312,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kato, T.","contributorId":93195,"corporation":false,"usgs":true,"family":"Kato","given":"T.","email":"","affiliations":[],"preferred":false,"id":363313,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Rundle, J. B.","contributorId":17766,"corporation":false,"usgs":false,"family":"Rundle","given":"J.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":363310,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70012334,"text":"70012334 - 1980 - Supplementary modification and introduction of code numbers to the low-latitude coccolith biostratigraphic zonation (Bukry, 1973; 1975)","interactions":[],"lastModifiedDate":"2024-10-02T16:34:40.649038","indexId":"70012334","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2673,"text":"Marine Micropaleontology","active":true,"publicationSubtype":{"id":10}},"title":"Supplementary modification and introduction of code numbers to the low-latitude coccolith biostratigraphic zonation (Bukry, 1973; 1975)","docAbstract":"<p>No abstract available.&nbsp;</p>","language":"English","publisher":"Elsevier","doi":"10.1016/0377-8398(80)90016-X","usgsCitation":"Okada, H., and Bukry, D., 1980, Supplementary modification and introduction of code numbers to the low-latitude coccolith biostratigraphic zonation (Bukry, 1973; 1975): Marine Micropaleontology, v. 5, p. 321-325, https://doi.org/10.1016/0377-8398(80)90016-X.","productDescription":"5 p.","startPage":"321","endPage":"325","costCenters":[],"links":[{"id":222193,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b9f74e4b08c986b31e5bb","contributors":{"authors":[{"text":"Okada, H.","contributorId":14097,"corporation":false,"usgs":true,"family":"Okada","given":"H.","email":"","affiliations":[],"preferred":false,"id":363305,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bukry, D.","contributorId":15338,"corporation":false,"usgs":true,"family":"Bukry","given":"D.","affiliations":[],"preferred":false,"id":363306,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70012330,"text":"70012330 - 1980 - Computational methods for inverse problems in geophysics: Inversion of travel time observations","interactions":[],"lastModifiedDate":"2020-03-20T06:55:43","indexId":"70012330","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","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":"Computational methods for inverse problems in geophysics: Inversion of travel time observations","docAbstract":"<p>General ways of solving various inverse problems are studied for given travel time observations between sources and receivers. These problems are separated into three components: (a) the representation of the unknown quantities appearing in the model; (b) the nonlinear least-squares problem; (c) the direct, two-point ray-tracing problem used to compute travel time once the model parameters are given. Novel software is described for (b) and (c), and some ideas given on (a). Numerical results obtained with artificial data and an implementation of the algorithm are also presented.</p>","language":"English","publisher":"Elsevier","doi":"10.1016/0031-9201(80)90063-1","issn":"00319201","usgsCitation":"Pereyra, V., Keller, H., and Lee, W., 1980, Computational methods for inverse problems in geophysics: Inversion of travel time observations: Physics of the Earth and Planetary Interiors, v. 21, no. 2-3, p. 120-125, https://doi.org/10.1016/0031-9201(80)90063-1.","productDescription":"6 p.","startPage":"120","endPage":"125","numberOfPages":"6","costCenters":[],"links":[{"id":222133,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"21","issue":"2-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f951e4b0c8380cd4d570","contributors":{"authors":[{"text":"Pereyra, V.","contributorId":72932,"corporation":false,"usgs":true,"family":"Pereyra","given":"V.","affiliations":[],"preferred":false,"id":363296,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Keller, H.B.","contributorId":71697,"corporation":false,"usgs":true,"family":"Keller","given":"H.B.","email":"","affiliations":[],"preferred":false,"id":363295,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lee, W.H.K.","contributorId":35303,"corporation":false,"usgs":true,"family":"Lee","given":"W.H.K.","affiliations":[],"preferred":false,"id":363294,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70012329,"text":"70012329 - 1980 - Rate of mercury loss from contaminated estuarine sediments","interactions":[],"lastModifiedDate":"2017-12-14T16:35:31","indexId":"70012329","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1759,"text":"Geochimica et Cosmochimica Acta","active":true,"publicationSubtype":{"id":10}},"title":"Rate of mercury loss from contaminated estuarine sediments","docAbstract":"<p>The concentration of mercury in contaminated estuarine sediments of Bellingham Bay, Washington was found to decrease with a half-time of about 1.3 yr after the primary anthropogenic source of mercury was removed. <i>In situ</i> measurements of the mercury flux from sediments, in both dissolved and volatile forms, could not account for this decrease. This result suggests that the removal of mercury is associated with sediment particles transported out of the study area. This decrease was modeled using a steady-state mixing model.</p><p>Mercury concentrations in anoxic interstitial waters reached 3.5 μg/l, 126 times higher than observed in the overlying seawater. Mercury fluxes from these sediments ranged from 1.2 to 2.8 × 10<sup>−5</sup> ng/cm<sup>2</sup>/sec, all in a soluble form. In general, higher Hg fluxes were associated with low oxygen or reducing conditions in the overlying seawater. In contrast, no flux was measurable from oxidizing interstitial water having mercury concentrations of 0.01-0.06 μ/l.</p>","language":"English","publisher":"Elsevier","doi":"10.1016/0016-7037(80)90137-4","issn":"00167037","usgsCitation":"Bothner, M., Jahnke, R., Peterson, M.L., and Carpenter, R., 1980, Rate of mercury loss from contaminated estuarine sediments: Geochimica et Cosmochimica Acta, v. 44, no. 2, p. 273-285, https://doi.org/10.1016/0016-7037(80)90137-4.","productDescription":"13 p.","startPage":"273","endPage":"285","costCenters":[],"links":[{"id":222132,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"44","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a9537e4b0c8380cd81892","contributors":{"authors":[{"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":363292,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Jahnke, R.A.","contributorId":33060,"corporation":false,"usgs":true,"family":"Jahnke","given":"R.A.","email":"","affiliations":[],"preferred":false,"id":363290,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Peterson, M. L.","contributorId":49930,"corporation":false,"usgs":false,"family":"Peterson","given":"M.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":363291,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Carpenter, R.","contributorId":94793,"corporation":false,"usgs":true,"family":"Carpenter","given":"R.","affiliations":[],"preferred":false,"id":363293,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70012328,"text":"70012328 - 1980 - Ocean eddy structure by satellite radar altimetry required for iceberg towing","interactions":[],"lastModifiedDate":"2023-09-21T15:36:33.749133","indexId":"70012328","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1264,"text":"Cold Regions Science and Technology","active":true,"publicationSubtype":{"id":10}},"title":"Ocean eddy structure by satellite radar altimetry required for iceberg towing","docAbstract":"<p><span>Models for the towing of large tabular icebergs give towing speeds of 0.5 knots to 1.0 knots relative to the ambient near surface current. Recent oceanographic research indicates that the world oceans are not principally composed of large steady-state current systems, like the Gulf Stream, but that most of the ocean momentum is probably involved in intense rings, formed by meanders of the large streams, and in mid-ocean eddies. These rings and eddies have typical dimensions on the order of 200 km with dynamic height anomalies across them of tens-of-centimeters to a meter. They migrate at speeds on the order of a few cm/sec. Current velocities as great as 3 knots have been observed in rings, and currents of 1 knot are common. Thus, the successful towing of icebergs is dependent on the ability to locate, measure, and track ocean rings and eddies. To accomplish this systematically on synoptic scales appears to be possible only by using satelliteborne radar altimeters. Ocean current and eddy structures as observed by the radar altimeters on the GEOS-3 and Seasat-1 satellites are presented and compared. Several satellite programs presently being planned call for flying radar altimeters in polar or near-polar orbits in the mid-1980 time frame. Thus, by the time tows of large icebergs will probably be attempted, it is possible synoptic observations of ocean rings and eddies which can be used to ascertain their location, size, intensity, and translation velocity will be a reality.</span></p>","language":"English","publisher":"Elsevier","doi":"10.1016/0165-232X(80)90049-X","usgsCitation":"Campbell, W.J., Cheney, R.E., Marsh, J.G., and Mognard, N.M., 1980, Ocean eddy structure by satellite radar altimetry required for iceberg towing: Cold Regions Science and Technology, v. 1, no. 3-4, p. 211-221, https://doi.org/10.1016/0165-232X(80)90049-X.","productDescription":"11 p.","startPage":"211","endPage":"221","numberOfPages":"11","costCenters":[],"links":[{"id":222131,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"1","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a6c8ee4b0c8380cd74caa","contributors":{"authors":[{"text":"Campbell, W. J.","contributorId":8614,"corporation":false,"usgs":true,"family":"Campbell","given":"W.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":363286,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Cheney, R. E.","contributorId":87290,"corporation":false,"usgs":false,"family":"Cheney","given":"R.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":363289,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Marsh, J. G.","contributorId":53952,"corporation":false,"usgs":false,"family":"Marsh","given":"J.","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":363288,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Mognard, N. M.","contributorId":27612,"corporation":false,"usgs":false,"family":"Mognard","given":"N.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":363287,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70012321,"text":"70012321 - 1980 - Modern and ancient submarine fans: Discussion of papers by Walker and Normark.","interactions":[],"lastModifiedDate":"2023-01-12T15:37:52.794419","indexId":"70012321","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","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":"Modern and ancient submarine fans: Discussion of papers by Walker and Normark.","docAbstract":"<p>No abstract available.</p>","language":"English","publisher":"American Association of Petroleum Geologists","doi":"10.1306/2F91943B-16CE-11D7-8645000102C1865D","usgsCitation":"Nilsen, T., 1980, Modern and ancient submarine fans: Discussion of papers by Walker and Normark.: American Association of Petroleum Geologists Bulletin, v. 64, no. 7, p. 1094-1101, https://doi.org/10.1306/2F91943B-16CE-11D7-8645000102C1865D.","productDescription":"8 p.","startPage":"1094","endPage":"1101","numberOfPages":"8","costCenters":[],"links":[{"id":222066,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"64","issue":"7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5c8ce4b0c8380cd6fd92","contributors":{"authors":[{"text":"Nilsen, Tor H.","contributorId":100016,"corporation":false,"usgs":true,"family":"Nilsen","given":"Tor H.","affiliations":[],"preferred":false,"id":363273,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70012289,"text":"70012289 - 1980 - The morphology of the Martian surface","interactions":[],"lastModifiedDate":"2012-03-12T17:19:03","indexId":"70012289","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3454,"text":"Space Science Reviews","active":true,"publicationSubtype":{"id":10}},"title":"The morphology of the Martian surface","docAbstract":"Most of the southern hemisphere of Mars is densely cratered and stands 1-3 km above the topographic datum. The northern hemisphere is more sparsely cratered and elevations are generally below the datum. A broad rise, the Tharsis bulge, centered at 14?? S, 101?? W, is 8000 km across and 10 km above the datum at its summit. The densely cratered terrain has two main components; very ancient crust, nearly saturated with large craters, and younger intercrater plains. In many areas the older unit is fractured and extensively dissected by small channels. The younger intercrater plains are distinctly layered in places and less dissected, less fractured, and less cratered. Both units probably date from very early in the planet's history. Cratered plains cover much of the northern hemisphere and are highly variegated. Those around the large volcanoes are covered with numerous volcanic flows whereas in other areas the plains are featureless except for craters and lunar mare-like ridges. Between 40?? N and 60?? N the plains are complex with various kinds of striped and patterned ground, low escarpments, and isolated irregularly shaped mesas. Their peculiar morphology has been attributed, in part, to the repeated deposition and removal of volatile-rich debris layers. Along the boundary between the northern plains and the densely cratered terrain to the south, the plains and cratered terrain complexly inter-finger. The old terrain forms the high ground and appears to have undergone mass wasting on a large scale. In several areas, particularly south of Chryse Planitia, the old, cratered surface has collapsed to form chaotic terrain. Large channels, tens of kilometers wide and hundreds of kilometers long, with numerous characteristics suggestive of catastrophic flooding, commonly emerge from the chaotic areas. Much of the area between 50?? W and 180?? W and 50?? N and 50?? S is cut by fractures radial to the center of the Tharsis bulge. The equatorial canyon system, Valles Marineris, is radial to the bulge and appears to have formed largely by faulting along the radial fractures, although it has also been extensively modified by various mass wasting and fluvial processes. Most but not all volcanoes are in the Tharsis and Elysium regions. The largest resemble terrestrial shield volcanoes except for scale; the edifices, flow features and calderas are all far larger than their terrestrial counterparts. Most impact craters on Mars are surrounded by layers of ejecta, each with a distil ridge. This unique morphology coupled with other surface characteristics suggests large amounts of ground ice. Layered deposits at both poles appear to be relatively young, volatile-rich, aeolian deposits. The north pole is also surrounded by a continuous belt of dunes several tens of kilometers across. In most other places, aeolian modification of the surface at a scale of several tens of meters appears slight despite annual global dust storms. ?? 1980 D. Reidel Publishing Co.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Space Science Reviews","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisherLocation":"Kluwer Academic Publishers","doi":"10.1007/BF00221929","issn":"00386308","usgsCitation":"Carr, M.H., 1980, The morphology of the Martian surface: Space Science Reviews, v. 25, no. 3, p. 231-284, https://doi.org/10.1007/BF00221929.","startPage":"231","endPage":"284","numberOfPages":"54","costCenters":[],"links":[{"id":205254,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF00221929"},{"id":222530,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"25","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505badeee4b08c986b323e74","contributors":{"authors":[{"text":"Carr, M. H.","contributorId":84727,"corporation":false,"usgs":true,"family":"Carr","given":"M.","email":"","middleInitial":"H.","affiliations":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"preferred":false,"id":363192,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70012271,"text":"70012271 - 1980 - Stable isotope and fluid inclusion studies of carbonate deposits from the Tolfa Mountains mining district (Latium, central Italy)","interactions":[],"lastModifiedDate":"2012-03-12T17:19:09","indexId":"70012271","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2746,"text":"Mineralium Deposita","active":true,"publicationSubtype":{"id":10}},"title":"Stable isotope and fluid inclusion studies of carbonate deposits from the Tolfa Mountains mining district (Latium, central Italy)","docAbstract":"Carbon and oxygen isotope analyses were made of representative samples of calcite and quartz from the carbonate deposits in the Tolfa Mountains mining district. Measurements were also made of hydrogen isotope compositions, filling temperatures and salinities of fluid inclusions in these minerals. There are three stages of mineralization at Tolfa. In stage I, characterized by calc-silicate hornfels, the carbonates have relatively high ?? 18O values of 14.5 to 21.6 suggesting a rather low water/rock ratio. ??13C values of -0.3 to 2.1 indicate that appreciable decarbonation or introduction of deep-seated carbon did not occur. Stage II is marked by phanerocrystalline carbonates; ?? 18O values of 13.1 to 20.0 and ??13C values of 0.7 to 5.0 identify them as hydrothermal veins rather than marbles. ?? D values of -56 to -50 for inclusion fluids suggest a possible magmatic component to the hydrothermal fluid. Filling temperatures of coarse-grained samples of Calcite II are 309?? to 362?? C with a salinity range of 5.3 to 7.1 weight percent NaCl. Calculated ??18O values of 11-12 for these fluids are again indicative of low water/rock ratios. The sparry calcites of stage III have ??18O and ??13C values of 8.1 to 12.9 and -1.7 to 3.2, respectively. ?? D values of inclusion fluids are -40 to -33, clearly heavier than in earlier stages and similar to values of modern local ground waters. A salinity measurement of <0.1 weight percent NaCl in a sample of Calcite III is compatible with a relatively unaltered ground water origin for this fluid. Precipitation of the sparry calcite took place at much lower temperatures, around 160?? C. For quartz, ??18O values of 9.3 to 12.4 and ?? D values for inclusions of -53 to -28 are consistent with its late occurrence and paragenetic link with associated carbonates. ?? 1980 Springer-Verlag.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Mineralium Deposita","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisherLocation":"Springer-Verlag","doi":"10.1007/BF00202800","issn":"00264598","usgsCitation":"Masi, U., Ferrini, V., O’Neil, J.R., and Batchelder, J.N., 1980, Stable isotope and fluid inclusion studies of carbonate deposits from the Tolfa Mountains mining district (Latium, central Italy): Mineralium Deposita, v. 15, no. 3, p. 351-359, https://doi.org/10.1007/BF00202800.","startPage":"351","endPage":"359","numberOfPages":"9","costCenters":[],"links":[{"id":205222,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF00202800"},{"id":222298,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"15","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b966ae4b08c986b31b4c5","contributors":{"authors":[{"text":"Masi, U.","contributorId":34654,"corporation":false,"usgs":true,"family":"Masi","given":"U.","email":"","affiliations":[],"preferred":false,"id":363143,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ferrini, V.","contributorId":51459,"corporation":false,"usgs":true,"family":"Ferrini","given":"V.","email":"","affiliations":[],"preferred":false,"id":363144,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"O’Neil, J. R.","contributorId":69633,"corporation":false,"usgs":true,"family":"O’Neil","given":"J.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":363145,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Batchelder, J. N.","contributorId":89870,"corporation":false,"usgs":true,"family":"Batchelder","given":"J.","email":"","middleInitial":"N.","affiliations":[],"preferred":false,"id":363146,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70012258,"text":"70012258 - 1980 - Morphology of Lonar Crater, India: Comparisons and implications","interactions":[],"lastModifiedDate":"2012-03-12T17:19:05","indexId":"70012258","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3570,"text":"The Moon and the Planets","active":true,"publicationSubtype":{"id":10}},"title":"Morphology of Lonar Crater, India: Comparisons and implications","docAbstract":"Lonar Crater is a young meteorite impact crater emplaced in Deccan basalt. Data from 5 drillholes, a gravity network, and field mapping are used to reconstruct its original dimensions, delineate the nature of the pre-impact target rocks, and interpret the emplacement mode of the ejecta. Our estimates of the pre-erosion dimensions are: average diameter of 1710 m; average rim height of 40 m (30-35 m of rim rock uplift, 5-10 m of ejected debris); depth of 230-245 m (from rim crest to crater floor). The crater's circularity index is 0.9 and is unlikely to have been lower in the past. There are minor irregularities in the original crater floor (present sediment-breccia boundary) possibly due to incipient rebound effects. A continuous ejecta blanket extends an average of 1410 m beyond the pre-erosion rim crest. In general, 'fresh' terrestrial craters, less than 10 km in diameter, have smaller depth/diameter and larger rim height/diameter ratios than their lunar counterparts. Both ratios are intermediate for Mercurian craters, suggesting that crater shape is gravity dependent, all else being equal. Lonar demonstrates that all else is not always equal. Its depth/diameter ratio is normal but, because of less rim rock uplift, its rim height/diameter ratio is much smaller than both 'fresh' terrestrial and lunar impact craters. The target rock column at Lonar consists of one or more layers of weathered, soft basalt capped by fresh, dense flows. Plastic deformation and/or compaction of this lower, incompetent material probably absorbed much of the energy normally available in the cratering process for rim rock uplift. A variety of features within the ejecta blanket and the immediately underlying substrate, plus the broad extent of the blanket boundaries, suggest that a fluidized debris surge was the dominant mechanism of ejecta transportation and deposition at Lonar. In these aspects, Lonar should be a good analog for the 'fluidized craters' of Mars. ?? 1980 D. Reidel Publishing Co.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"The Moon and the Planets","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisherLocation":"Kluwer Academic Publishers","doi":"10.1007/BF00897591","issn":"01650807","usgsCitation":"Fudali, R., Milton, D., Fredriksson, K., and Dube, A., 1980, Morphology of Lonar Crater, India: Comparisons and implications: The Moon and the Planets, v. 23, no. 4, p. 493-515, https://doi.org/10.1007/BF00897591.","startPage":"493","endPage":"515","numberOfPages":"23","costCenters":[],"links":[{"id":205191,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF00897591"},{"id":222064,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"23","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5e52e4b0c8380cd7096a","contributors":{"authors":[{"text":"Fudali, R.F.","contributorId":26445,"corporation":false,"usgs":true,"family":"Fudali","given":"R.F.","email":"","affiliations":[],"preferred":false,"id":363112,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Milton, D.J.","contributorId":44121,"corporation":false,"usgs":true,"family":"Milton","given":"D.J.","email":"","affiliations":[],"preferred":false,"id":363113,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Fredriksson, K.","contributorId":11328,"corporation":false,"usgs":true,"family":"Fredriksson","given":"K.","email":"","affiliations":[],"preferred":false,"id":363111,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Dube, A.","contributorId":8615,"corporation":false,"usgs":true,"family":"Dube","given":"A.","email":"","affiliations":[],"preferred":false,"id":363110,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70012256,"text":"70012256 - 1980 - A model to forecast short-term snowmelt runoff using synoptic observations of streamflow, temperature, and precipitation","interactions":[],"lastModifiedDate":"2018-02-05T12:29:02","indexId":"70012256","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3722,"text":"Water Resources Research","onlineIssn":"1944-7973","printIssn":"0043-1397","active":true,"publicationSubtype":{"id":10}},"title":"A model to forecast short-term snowmelt runoff using synoptic observations of streamflow, temperature, and precipitation","docAbstract":"<p><span>Snowmelt runoff is forecast with a statistical model that utilizes daily values of stream discharge, gaged precipitation, and maximum and minimum observations of air temperature. Synoptic observations of these variables are made at existing low- and medium-altitude weather stations, thus eliminating the difficulties and expense of new, high-altitude installations. Four model development steps are used to demonstrate the influence on prediction accuracy of basin storage, a preforecast test season, air temperature (to estimate ablation), and a prediction based on storage. Daily ablation is determined by a technique that employs both mean temperature and a radiative index. Radiation (both long- and short-wave components) is approximated by using the range in daily temperature, which is shown to be closely related to mean cloud cover. A technique based on the relationship between prediction error and prediction season weather utilizes short-term forecasts of precipitation and temperature to improve the final prediction. Verification of the model is accomplished by a split sampling technique for the 1960–1977 period. Short- term (5–15 days) predictions of runoff throughout the main snowmelt season are demonstrated for mountain drainages in western Washington, south-central Arizona, western Montana, and central California. The coefficient of prediction (</span><i>C</i><sub><i>p</i></sub><span>) based on actual, short-term predictions for 18 years is for Thunder Creek (Washington), 0.69; for South Fork Flathead River (Montana), 0.45; for the Black River (Arizona), 0.80; and for the Kings River (California), 0.80.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/WR016i004p00778","usgsCitation":"Tangborn, W.V., 1980, A model to forecast short-term snowmelt runoff using synoptic observations of streamflow, temperature, and precipitation: Water Resources Research, v. 16, no. 4, p. 778-786, https://doi.org/10.1029/WR016i004p00778.","productDescription":"9 p.","startPage":"778","endPage":"786","costCenters":[],"links":[{"id":222062,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"16","issue":"4","noUsgsAuthors":false,"publicationDate":"2010-07-09","publicationStatus":"PW","scienceBaseUri":"5059e482e4b0c8380cd46694","contributors":{"authors":[{"text":"Tangborn, Wendell V.","contributorId":32152,"corporation":false,"usgs":true,"family":"Tangborn","given":"Wendell","email":"","middleInitial":"V.","affiliations":[],"preferred":false,"id":363107,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70012242,"text":"70012242 - 1980 - Elastic moduli of rock glasses under pressure to 8 kilobars and geophysical implications","interactions":[],"lastModifiedDate":"2024-07-16T16:56:57.73129","indexId":"70012242","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","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":"Elastic moduli of rock glasses under pressure to 8 kilobars and geophysical implications","docAbstract":"<p><span>Shear and longitudinal velocities were measured by the ultrasonic phase comparison method as a function of pressure to 8 kbar on synthetic glasses of basalt, andesite, rhyolite, and quartz composition and on natural obsidian. Velocities of most of the glasses decrease anomalously with pressure, but increasingly more-normal behavior occurs with decrease in SiO</span><sub>2</sub><span>&nbsp;content. The pressure derivatives of rigidity and bulk modulus increase linearly, from −3.39 to −0.26 and from −5.91 to +2.09, respectively, with decrease in SiO</span><sub>2</sub><span>&nbsp;content from 100 to 49%. The change from negative to positive in the pressure derivatives of both moduli and observed at Poisson's ratio of about 0.25 is consistent with the Smyth model for the anomalous elastic behavior of glass. If the temperature in the upper mantle is about 1500°C, tholeiitic basalt would be molten in accordance with the partial melt explanation for the low-velocity zone; at 1300°C and below, basalt would be in the glassy state, especially if more felsic than tholeiite. At a temperature of 1370°C and at 30 kbar, reasonable values for the upper mantle at 100 km depth, the basalt glass of this study would have a viscosity of about 10</span><sup>13</sup><span>&nbsp;P. On the basis of the theory of viscoelasticity the glass would support shear wave propagation at frequencies above 0.1 Hz. Under such conditions of PT, 10 to 30% basalt glass in a matrix either of eclogite or olivine would reduce the seismic velocities by 3 to 9% and could also account for the values observed in the low-velocity zone.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB085iB11p06461","issn":"01480227","usgsCitation":"Meister, R., Robertson, E., Werke, R., and Raspet, R., 1980, Elastic moduli of rock glasses under pressure to 8 kilobars and geophysical implications: Journal of Geophysical Research Solid Earth, v. 85, no. B11, p. 6461-6470, https://doi.org/10.1029/JB085iB11p06461.","productDescription":"10 p.","startPage":"6461","endPage":"6470","numberOfPages":"10","costCenters":[],"links":[{"id":221875,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"85","issue":"B11","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"505a0881e4b0c8380cd51b51","contributors":{"authors":[{"text":"Meister, R.","contributorId":96003,"corporation":false,"usgs":true,"family":"Meister","given":"R.","email":"","affiliations":[],"preferred":false,"id":363072,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Robertson, E.C.","contributorId":43365,"corporation":false,"usgs":true,"family":"Robertson","given":"E.C.","email":"","affiliations":[],"preferred":false,"id":363069,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Werke, R.W.","contributorId":88879,"corporation":false,"usgs":true,"family":"Werke","given":"R.W.","email":"","affiliations":[],"preferred":false,"id":363071,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Raspet, R.","contributorId":77656,"corporation":false,"usgs":true,"family":"Raspet","given":"R.","affiliations":[],"preferred":false,"id":363070,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70012231,"text":"70012231 - 1980 - A three-dimensional model to predict future oil discoveries in spatially connected multiple plays","interactions":[],"lastModifiedDate":"2012-03-12T17:19:09","indexId":"70012231","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2554,"text":"Journal of the International Association for Mathematical Geology","active":true,"publicationSubtype":{"id":10}},"title":"A three-dimensional model to predict future oil discoveries in spatially connected multiple plays","docAbstract":"A discovery-process model that had been devised previously to estimate the size distribution of oil and gas fields remaining to be discovered in a single producing horizon was adapted to a basin containing spatially connected multiple plays and producing horizons. This model used the concept of the area of influence of wells to estimate search effort. Other variables estimated from the historical drilling and discovery data are the effective basin size and the exploration-drilling efficiency. Data from the Midland Basin are used to illustrate how the model works. ?? 1980 Plenum Publishing Corporation.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of the International Association for Mathematical Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisherLocation":"Kluwer Academic Publishers-Plenum Publishers","doi":"10.1007/BF01028880","issn":"00205958","usgsCitation":"Schuenemeyer, J., Drew, L., and Bawiec, W., 1980, A three-dimensional model to predict future oil discoveries in spatially connected multiple plays: Journal of the International Association for Mathematical Geology, v. 12, no. 5, p. 459-472, https://doi.org/10.1007/BF01028880.","startPage":"459","endPage":"472","numberOfPages":"14","costCenters":[],"links":[{"id":205278,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF01028880"},{"id":222646,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"12","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e5fee4b0c8380cd470ab","contributors":{"authors":[{"text":"Schuenemeyer, J.H.","contributorId":106094,"corporation":false,"usgs":true,"family":"Schuenemeyer","given":"J.H.","affiliations":[],"preferred":false,"id":363042,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Drew, L.J.","contributorId":69157,"corporation":false,"usgs":true,"family":"Drew","given":"L.J.","email":"","affiliations":[],"preferred":false,"id":363040,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bawiec, W.J.","contributorId":71540,"corporation":false,"usgs":true,"family":"Bawiec","given":"W.J.","affiliations":[],"preferred":false,"id":363041,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70012230,"text":"70012230 - 1980 - Small impact craters in the lunar regolith - Their morphologies, relative ages, and rates of formation","interactions":[],"lastModifiedDate":"2012-03-12T17:19:09","indexId":"70012230","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3570,"text":"The Moon and the Planets","active":true,"publicationSubtype":{"id":10}},"title":"Small impact craters in the lunar regolith - Their morphologies, relative ages, and rates of formation","docAbstract":"Apparently, there are two types of size-frequency distributions of small lunar craters (???1-100 m across): (1) crater production distributions for which the cumulative frequency of craters is an inverse function of diameter to power near 2.8, and (2) steady-state distributions for which the cumulative frequency of craters is inversely proportional to the square of their diameters. According to theory, cumulative frequencies of craters in each morphologic category within the steady-state should also be an inverse function of the square of their diameters. Some data on frequency distribution of craters by morphologic types are approximately consistent with theory, whereas other data are inconsistent with theory. A flux of crater producing objects can be inferred from size-frequency distributions of small craters on the flanks and ejecta of craters of known age. Crater frequency distributions and data on the craters Tycho, North Ray, Cone, and South Ray, when compared with the flux of objects measured by the Apollo Passive Seismometer, suggest that the flux of objects has been relatively constant over the last 100 m.y. (within 1/3 to 3 times of the flux estimated for Tycho). Steady-state frequency distributions for craters in several morphologic categories formed the basis for estimating the relative ages of craters and surfaces in a system used during the Apollo landing site mapping program of the U.S. Geological Survey. The relative ages in this system are converted to model absolute ages that have a rather broad range of values. The range of values of the absolute ages are between about 1/3 to 3 times the assigned model absolute age. ?? 1980 D. Reidel Publishing Co.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"The Moon and the Planets","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisherLocation":"Kluwer Academic Publishers","doi":"10.1007/BF00899820","issn":"01650807","usgsCitation":"Moore, H., Boyce, J.M., and Hahn, D., 1980, Small impact craters in the lunar regolith - Their morphologies, relative ages, and rates of formation: The Moon and the Planets, v. 23, no. 2, p. 231-252, https://doi.org/10.1007/BF00899820.","startPage":"231","endPage":"252","numberOfPages":"22","costCenters":[],"links":[{"id":205277,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF00899820"},{"id":222645,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"23","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b9182e4b08c986b319949","contributors":{"authors":[{"text":"Moore, H. J.","contributorId":71962,"corporation":false,"usgs":true,"family":"Moore","given":"H. J.","affiliations":[],"preferred":false,"id":363038,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Boyce, J. M.","contributorId":85952,"corporation":false,"usgs":true,"family":"Boyce","given":"J.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":363039,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hahn, D.A.","contributorId":61103,"corporation":false,"usgs":true,"family":"Hahn","given":"D.A.","email":"","affiliations":[],"preferred":false,"id":363037,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70012219,"text":"70012219 - 1980 - Ice-sheet glaciation of the Puget lowland, Washington, during the Vashon Stade (late Pleistocene)","interactions":[],"lastModifiedDate":"2025-07-10T16:48:37.840047","indexId":"70012219","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3218,"text":"Quaternary Research","active":true,"publicationSubtype":{"id":10}},"title":"Ice-sheet glaciation of the Puget lowland, Washington, during the Vashon Stade (late Pleistocene)","docAbstract":"<p><span>During the Vashon Stade of the Fraser Glaciation, about 15,000–13,000 yr B.P., a lobe of the Cordilleran Ice Sheet occupied the Puget lowland of western Washington. At its maximum extent about 14,000 yr ago, the ice sheet extended across the Puget lowland between the Cascade Range and Olympic Mountains and terminated about 80 km south of Seattle. Meltwater streams drained southwest to the Pacific Ocean and built broad outwash trains south of the ice margin. Reconstructed longitudinal profiles for the Puget lobe at its maximum extent are similar to the modern profile of Malaspina Glacier, Alaska, suggesting that the ice sheet may have been in a near-equilibrium state at the glacial maximum. Progressive northward retreat from the terminal zone was accompanied by the development of ice-marginal streams and proglacial lakes that drained southward during initial retreat, but northward during late Vashon time. Relatively rapid retreat of the Juan de Fuca lobe may have contributed to partial stagnation of the northwestern part of the Puget lobe. Final destruction of the Puget lobe occurred when the ice retreated north of Admiralty Inlet. The sea entered the Puget lowland at this time, allowing the deposition of glacial-marine sediments which now occur as high as 50 m altitude. These deposits, together with ice-marginal meltwater channels presumed to have formed above sea level during deglaciation, suggest that a significant amount of postglacial isostatic and(or) tectonic deformation has occurred in the Puget lowland since deglaciation.</span></p>","language":"English","publisher":"Elsevier","doi":"10.1016/0033-5894(80)90059-9","issn":"00335894","usgsCitation":"Thorson, R., 1980, Ice-sheet glaciation of the Puget lowland, Washington, during the Vashon Stade (late Pleistocene): Quaternary Research, v. 13, no. 3, p. 303-321, https://doi.org/10.1016/0033-5894(80)90059-9.","productDescription":"19 p.","startPage":"303","endPage":"321","costCenters":[],"links":[{"id":222468,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Washington","otherGeospatial":"Puget lowland, western Washington","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"coordinates\": [\n          [\n            [\n              -123.12087070552147,\n              48.27218726718516\n            ],\n            [\n              -123.12087070552147,\n              47.13545914239012\n            ],\n            [\n              -121.71374171000068,\n              47.13545914239012\n            ],\n            [\n              -121.71374171000068,\n              48.27218726718516\n            ],\n            [\n              -123.12087070552147,\n              48.27218726718516\n            ]\n          ]\n        ],\n        \"type\": \"Polygon\"\n      }\n    }\n  ]\n}","volume":"13","issue":"3","noUsgsAuthors":false,"publicationDate":"2017-01-20","publicationStatus":"PW","scienceBaseUri":"505a37f5e4b0c8380cd61300","contributors":{"authors":[{"text":"Thorson, R.M.","contributorId":74132,"corporation":false,"usgs":true,"family":"Thorson","given":"R.M.","email":"","affiliations":[],"preferred":false,"id":363012,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70012218,"text":"70012218 - 1980 - Transition of basaltic lava from pahoehoe to aa, Kilauea Volcano, Hawaii: Field observations and key factors","interactions":[],"lastModifiedDate":"2017-04-25T10:33:28","indexId":"70012218","displayToPublicDate":"1980-01-01T00:00:00","publicationYear":"1980","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2499,"text":"Journal of Volcanology and Geothermal Research","active":true,"publicationSubtype":{"id":10}},"title":"Transition of basaltic lava from pahoehoe to aa, Kilauea Volcano, Hawaii: Field observations and key factors","docAbstract":"<p>Nearly all Hawaiian basaltic lava erupts as pahoehoe, and some changes to aa during flowage and cooling; factors governing the transition involve certain critical relations between viscosity and rate of shear strain. If the lava slows, cools, and stops in direct response to concomitant increase in viscosity before these critical relations are reached, it remains pahoehoe. But, if flow mechanics (flow rate, flow dimensions, slope, momentum, etc.) impel the lava to continue to move and deform even after it has become highly viscous, the critical relations may be reached and the lava changes to aa.</p><p>Typical modes of transition from pahoehoe to aa include: (1) spontaneous formation of relatively stiff clots in parts of the flowing lava where shear rate is highest; these clots grow into discrete, rough, sticky masses to which the remaining fluid lava incrementally adheres; (2) fragmentation and immersion of solid or semi-solid surface crusts of pahoehoe by roiling movements of the flow, forming cores of discrete, tacky masses; (3) sudden renewed movement of lava stored and cooled within surface reservoirs to form clots. The masses, fragments, and clots in these transition modes are characterized by spinose, granulated surfaces; as flow movement continues, the masses and fragments aggregate, fracture, and grind together, completing the transition to aa.</p><p>Observations show that the critical relation between viscosity and rate of shear strain is inverse: if viscosity is low, a high rate of shear is required to begin the transition to aa; conversely, if viscosity is high, a much lower rate of shear will induce the transition. These relations can be demonstrated qualitatively with simple graphs, which can be used to examine the flow history of any selected finite lava element by tracing the path represented by its changing viscosity and shear rate. A broad, diffuse “transition threshold zone” in these graphs portrays the inverse critical relation between viscosity and shear rate; the transition to aa is represented by the path of the lava element crossing this zone.</p><p>Moving lava flows can be regarded as natural viscometers, by which shear stress and rate of shear strain at selected points can be determined and viscosity can be computed. By making such determinations under a wide range of conditions on pahoehoe, aa, and transitional flow types, the critical relations that control the pahoehoe-aa transition can be quantified.</p>","language":"English","publisher":"Elsevier","doi":"10.1016/0377-0273(80)90033-5","issn":"03770273","usgsCitation":"Peterson, D.W., and Tilling, R.I., 1980, Transition of basaltic lava from pahoehoe to aa, Kilauea Volcano, Hawaii: Field observations and key factors: Journal of Volcanology and Geothermal Research, v. 7, no. 3-4, p. 271-293, https://doi.org/10.1016/0377-0273(80)90033-5.","productDescription":"23 p.","startPage":"271","endPage":"293","costCenters":[],"links":[{"id":222467,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Hawaii","otherGeospatial":" Kilauea Volcano","volume":"7","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bb710e4b08c986b327039","contributors":{"authors":[{"text":"Peterson, Donald W.","contributorId":11209,"corporation":false,"usgs":true,"family":"Peterson","given":"Donald","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":363010,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Tilling, Robert I. 0000-0003-4263-7221 rtilling@usgs.gov","orcid":"https://orcid.org/0000-0003-4263-7221","contributorId":2567,"corporation":false,"usgs":true,"family":"Tilling","given":"Robert","email":"rtilling@usgs.gov","middleInitial":"I.","affiliations":[],"preferred":true,"id":363011,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
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