Instrumental-neutron-activation analyses are reported for two uncontaminated rocks, a phlogopite-rich clot, and two contaminated rocks from the Coyote Peak diatreme, northwestern California. These data, combined with Nd, Sr, and Pb isotopic evidence, have been modeled to a multi-stage evolution for the uncontaminated rocks. Fertile mantle material (refractory elements 2.5× chondritic abundances; Rb/Sr = 0.029 by weight) was depleted about 900 m.y. ago by congruent melting and removal of ~4% basaltic liquid; this depleted residue provided the source rock from which the Coyote Peak magma was ultimately derived. About 66 m.y. ago, the depleted mantle residue was incongruently melted in the presence of H2O and CO2 at a total pressure > 26 kb to yield ~0.5% of a Si-poor, Ca-rich melt. This melt then metasomatized depleted garnet-free harzburgite in the upper mantle at about 26 kb to produce a rock similar to phlogopite-bearing wehrlite. About 29 m.y. ago, this rock was subjected to an increase in pressure to >26 kb and incongruently melted to give ~0.5% of a second-stage melt resembling olivine melilitite in composition. Enroute to the surface, about 28% olivine and 2% titanomagnetite were lost from the highly fluid melt.
Coarse-grained phlogopite-rich clots in the uncontaminated rocks apparently crystallized from a latestage liquid derived from the uncontaminated melt. Contaminated rocks appear to be the result of partial assimilation of, and dilution by, ~14% Franciscan graywacke country rock.
The diatreme was emplaced near a converging plate margin where young hot oceanic mantle and crust of the Juan de Fuca plate was probably subducting obliquely beneath a thin lip of the North American plate. The unusual chemistry of the rocks may be the result of this complex tectonic setting which could also have included local strike-slip and extensional environments within the two plates pierced by the diatreme.
Analyses of sea level and current-meter data using digital filters and a variety of statistical methods show a variety of phenomena related to non-local coastal forcing and local tidal forcing in the northern reach of San Francisco Bay, a partially mixed estuary. Low-frequency variations in sea level are dominated by non-local variations in coastal sea level and also show a smaller influence from tidally induced fortnightly sea level variations. Low-frequency currents demonstrate a gravitational circulation which is modified by changes in tidal-current speed over the spring-neap tidal cycle. Transients in gravitational circulation induce internal oscillations with periods of two to four days.
","language":"English","publisher":"Elsevier","doi":"10.1016/0272-7714(85)90003-4","issn":"02727714","usgsCitation":"Walters, R.A., and Gartner, J.W., 1985, Subtidal sea level and current variations in the northern reach of San Francisco Bay: Estuarine, Coastal and Shelf Science, v. 21, no. 1, p. 17-32, https://doi.org/10.1016/0272-7714(85)90003-4.","productDescription":"16 p.","startPage":"17","endPage":"32","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":552,"text":"San Francisco Bay-Delta","active":false,"usgs":true},{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":222316,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","otherGeospatial":"San Francisco Bay","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -122.49288365903871,\n 37.83365947740121\n ],\n [\n -122.47252439747213,\n 37.783616975293626\n ],\n [\n -122.40918447259784,\n 37.79255562354507\n ],\n [\n -122.39108735120529,\n 37.76752468391663\n ],\n [\n -122.30965030493846,\n 37.79613078009476\n ],\n [\n -122.28476676302354,\n 37.83187282919371\n ],\n [\n -122.30512602459041,\n 37.91044441089936\n ],\n [\n -122.3435824075495,\n 37.92650554655222\n ],\n [\n -122.39334949137933,\n 37.9443471390919\n ],\n [\n -122.37525236998678,\n 37.960400869467094\n ],\n [\n -122.35036882807188,\n 37.98714928977874\n ],\n [\n -122.31417458528654,\n 37.994280555594\n ],\n [\n -122.28702890319758,\n 38.0014111281601\n ],\n [\n -122.2576210809346,\n 38.03883525882202\n ],\n [\n -122.2417860997161,\n 38.04774294894307\n ],\n [\n -122.20106757658269,\n 38.04596149761244\n ],\n [\n -122.17392189449373,\n 38.0227986859378\n ],\n [\n -122.14451407223075,\n 38.015670193374916\n ],\n [\n -122.12415481066418,\n 38.01923452633122\n ],\n [\n -122.14225193205672,\n 38.05664955536099\n ],\n [\n -122.16713547397163,\n 38.07267871571531\n ],\n [\n -122.22368897832357,\n 38.08336287156371\n ],\n [\n -122.25309680058653,\n 38.117185732724664\n ],\n [\n -122.25535894076057,\n 38.1456559975872\n ],\n [\n -122.27571820232741,\n 38.16700140777752\n ],\n [\n -122.26893178180504,\n 38.23988440653355\n ],\n [\n -122.30965030493846,\n 38.23988440653355\n ],\n [\n -122.37751451016082,\n 38.20256320529367\n ],\n [\n -122.38656307085697,\n 38.15988696526969\n ],\n [\n -122.41144661277187,\n 38.16166564098279\n ],\n [\n -122.44764085555721,\n 38.12786338341408\n ],\n [\n -122.51324292060553,\n 38.12252475326176\n ],\n [\n -122.54038860269422,\n 38.07267871571531\n ],\n [\n -122.51550506077959,\n 38.03883525882202\n ],\n [\n -122.52907790182405,\n 38.01210568707435\n ],\n [\n -122.4680001171238,\n 37.98714928977874\n ],\n [\n -122.51098078043123,\n 37.978234232695755\n ],\n [\n -122.52681576165003,\n 37.94791493791199\n ],\n [\n -122.51324292060553,\n 37.912229154721274\n ],\n [\n -122.53812646252018,\n 37.87474044316498\n ],\n [\n -122.49288365903871,\n 37.83365947740121\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"21","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b9d9ae4b08c986b31d941","contributors":{"authors":[{"text":"Walters, R. 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W.","contributorId":81903,"corporation":false,"usgs":false,"family":"Gartner","given":"J.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":364193,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70012662,"text":"70012662 - 1985 - Geochemistry of great Salt Lake, Utah II: Pleistocene-Holocene evolution","interactions":[],"lastModifiedDate":"2020-01-19T11:15:38","indexId":"70012662","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","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":"Geochemistry of great Salt Lake, Utah II: Pleistocene-Holocene evolution","docAbstract":"Sedimentologic and biostratigraphic evidence is used to develop a geochemical model for Great Salt Lake, Utah, extending back some 30,000 yrs. B.P. Hydrologie conditions as defined by the water budget equation are characterized by a lake initially at a low, saline stage, rising by about 17,000 yrs. B.P. to fresh water basin-full conditions (Bonneville level) and then, after about 15,000 yrs. B.P., dropping rapidly to a saline stage again, as exemplified by the present situation. Inflow composition has changed through time in response to the hydrologie history. During fresh-water periods high discharge inflow is dominated by calcium bicarbonate-type river waters; during saline stages, low discharge, NaCl-rich hydrothermal springs are significant solute sources. This evolution in lake composition to NaCl domination is illustrated by the massive mirabilite deposition, free of halite, following the rapid drawdown until about 8,000 years ago, while historic droughts have yielded principally halite. Hydrologic history can be combined with inferred inflow composition to derive concentration curves with time for each major solute in the lake. Calcium concentrations before the drawdown were controlled by calcite solubility, and afterwards by aragonite. Significant amounts of solutes are removed from the lake by diffusion into the sediments. Na+, Cl- and SO42- are also involved in salt precipitation. By including pore fluid data, a surprisingly good fit has been obtained between solute input over the time period considered and the amounts actually found in lake brines, pore fluids, salt beds and sediments. Excess amounts are present for calcium, carbonate and silica, indicating detrital input.
","language":"English","publisher":"Elsevier","doi":"10.1016/0016-7037(85)90168-1","issn":"00167037","usgsCitation":"Spencer, R.J., Eugster, H., and Jones, B., 1985, Geochemistry of great Salt Lake, Utah II: Pleistocene-Holocene evolution: Geochimica et Cosmochimica Acta, v. 49, no. 3, p. 739-747, https://doi.org/10.1016/0016-7037(85)90168-1.","productDescription":"9 p.","startPage":"739","endPage":"747","numberOfPages":"9","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":222156,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Utah","otherGeospatial":"Great Salt Lake","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -113.22509765625,\n 40.6306300839918\n ],\n [\n -111.8792724609375,\n 40.6306300839918\n ],\n [\n -111.8792724609375,\n 41.713930073371294\n ],\n [\n -113.22509765625,\n 41.713930073371294\n ],\n [\n -113.22509765625,\n 40.6306300839918\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"49","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a16f7e4b0c8380cd55329","contributors":{"authors":[{"text":"Spencer, R. J.","contributorId":56664,"corporation":false,"usgs":true,"family":"Spencer","given":"R.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":364166,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Eugster, H.P.","contributorId":99992,"corporation":false,"usgs":true,"family":"Eugster","given":"H.P.","email":"","affiliations":[],"preferred":false,"id":364167,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Jones, B.F.","contributorId":52156,"corporation":false,"usgs":true,"family":"Jones","given":"B.F.","email":"","affiliations":[],"preferred":false,"id":364165,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70012658,"text":"70012658 - 1985 - Well bore breakouts and in situ stress","interactions":[],"lastModifiedDate":"2018-05-01T14:16:09","indexId":"70012658","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2312,"text":"Journal of Geophysical Research","active":true,"publicationSubtype":{"id":10}},"title":"Well bore breakouts and in situ stress","docAbstract":"The detailed cross-sectional shape of stress induced well bore breakouts has been studied using specially processed ultrasonic borehole televiewer data. Breakout shapes are shown for a variety of rock types and introduce a simple elastic failure model which explains many features of the observations. Both the observations and calculations indicate that the breakouts define relatively broad and flat curvilinear surfaces which enlarge the borehole in the direction of minimum horizontal compression. Refs.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Geophysical Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1029/JB090iB07p05523 ","issn":"01480227","usgsCitation":"Zoback, M.D., Moos, D., Mastin, L., and Anderson, R.N., 1985, Well bore breakouts and in situ stress: Journal of Geophysical Research, v. 90, no. B7, p. 5523-5530, https://doi.org/10.1029/JB090iB07p05523 .","startPage":"5523","endPage":"5530","numberOfPages":"8","costCenters":[{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true}],"links":[{"id":222093,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"90","issue":"B7","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"505bc395e4b08c986b32b269","contributors":{"authors":[{"text":"Zoback, Mark D.","contributorId":102455,"corporation":false,"usgs":true,"family":"Zoback","given":"Mark","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":364157,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Moos, Daniel","contributorId":48573,"corporation":false,"usgs":true,"family":"Moos","given":"Daniel","affiliations":[],"preferred":false,"id":364155,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Mastin, Larry","contributorId":36124,"corporation":false,"usgs":true,"family":"Mastin","given":"Larry","affiliations":[],"preferred":false,"id":364154,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Anderson, Roger N.","contributorId":95618,"corporation":false,"usgs":true,"family":"Anderson","given":"Roger","email":"","middleInitial":"N.","affiliations":[],"preferred":false,"id":364156,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70012654,"text":"70012654 - 1985 - Fluid inclusions in minerals from the geothermal fields of Tuscany, Italy","interactions":[],"lastModifiedDate":"2024-04-19T18:40:03.097504","indexId":"70012654","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1828,"text":"Geothermics","active":true,"publicationSubtype":{"id":10}},"title":"Fluid inclusions in minerals from the geothermal fields of Tuscany, Italy","docAbstract":"A reconnaissance study on fluid inclusions from the geothermal fields of Tuscany indicates that the hydrothermal minerals were formed by fluids which were, at least in part, boiling. Four types of aqueous inclusions were recognized: (A) two-phase (liquid + vapor) liquid rich, (B) two-phase (vapor + liquid) vapor rich, (C) polyphase hypersaline liquid rich and (D) three phase—H2O liquid + CO2 liquid + CO2-rich vapor. Freezing and heating microthermometric determinations are reported for 230 inclusions from samples from six wells. It is suggested that boiling of an originally homogeneous, moderately saline, CO2-bearing liquid phase produced a residual hypersaline brine and a CO2-rich vapor phase. There are indications of a temperature decrease in the geothermal field of Larderello, especially in its peripheral zones.
The McKinley sequence of granitic rocks consists of several discrete plutons in the central Alaska Range. Most of these plutons crop out south of the Denali fault system (DFS) in the Talkeetna quadrangle. Plutons of the McKinley sequence largely intrude deformed upper Meszoic flysch between the DFS and the northern edges of Wrangellia and the Peninsular terrane, which jointly make up the Talkeetna superterrane. The average K-Ar age of biotite from nine granites of the McKinley sequence is 57.3 Ma; Rb-Sr data for whole rock samples indicate that the McKinley sequence cannot be older than 60 Ma. A selected suite of 20 samples of granite and granodiorite range in SiO2 from 65.9 to 77.6%. All 20 samples are corundum normative, and 18 are moderately peraluminous. Initial 87Sr/86Sr ratios range from 0.7054 to 0.7085. The σ18O values range from +11.2 to +14.6‰. These high and variable Sr isotopic ratios, peraluminous nature, rare earth element patterns, and high σ18O values suggest that granitic rocks of the McKinley sequence crystallized from hybrid magmas produced by assimilation of sedimentary rocks by a mantle-derived melt. Mesozoic flysch is the likely source of the crustal component of the hybrid magmas. Geologic evidence suggests that the Talkeetna superterrane collided with stable Alaska after Early Cretaceous time. The flysch basin, lying south of stable Alaska, was closed by northward movement of the Talkeetna superterrane; maximum age for basin closure and terrane accretion is middle Cretaceous (Cenomanian). Paleomagnetic evidence indicates that all terranes north of the DFS have been part of stable Alaska since the Paleocene and that northward movement of Wrangellia was completed by 50 Ma. Granitic rocks of the McKinley sequence may be products of terrane accretion; the granitic rocks crystallized from hybrid magmas produced during terrane collision and deformation of the flysch basin. Isotopic ages of the McKinley sequence establish the time of final accretion of the Talkeetna superterrane as Paleocene.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB090iB13p11413","issn":"01480227","usgsCitation":"Lanphere, M.A., and Reed, B., 1985, The McKinley Sequence of granitic rocks: A key element in the accretionary history of southern Alaska: Journal of Geophysical Research Solid Earth, v. 90, no. B13, p. 11413-11430, https://doi.org/10.1029/JB090iB13p11413.","productDescription":"18 p.","startPage":"11413","endPage":"11430","costCenters":[],"links":[{"id":222475,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"90","issue":"B13","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"505ba7dde4b08c986b321855","contributors":{"authors":[{"text":"Lanphere, M. A.","contributorId":35298,"corporation":false,"usgs":true,"family":"Lanphere","given":"M.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":363435,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Reed, B.L.","contributorId":29434,"corporation":false,"usgs":true,"family":"Reed","given":"B.L.","email":"","affiliations":[],"preferred":false,"id":363434,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70012375,"text":"70012375 - 1985 - Element mobility during alteration of silicic ash to kaolinite - A study of tonstein","interactions":[],"lastModifiedDate":"2025-07-25T16:47:35.142486","indexId":"70012375","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3369,"text":"Sedimentology","active":true,"publicationSubtype":{"id":10}},"title":"Element mobility during alteration of silicic ash to kaolinite - A study of tonstein","docAbstract":"A laterally persistent kaolinitic mudstone parting (tonstein) occurring in a Wyoming coal bed of Eocene age was sampled to estimate the compositional contrast with a probable silicic ash precursor, and to determine the compositional influence of leached ash on immediately adjacent coal. With the exception of Al, and possibly Ti, the tonstein is highly to moderately leached of major elements, relative to a range of compositions estimated for silicic ash of the region. In agreement with the behaviour of geochemically similar major elements, alkali trace elements (Rb, Cs) are highly leached, transition-series metals moderately leached, and Ga is residual. Additional immobile trace elements are Zr and Hf but some other trace elements that are considered relatively immobile during low-temperature alteration (Th, Ta, Nb, REE, Y) were apparently leached by the low-Eh, low-pH, organic-rich pore fluids of the coal-forming swamp.
The migrational range of many of the leached elements is highly limited by the intimate association of tonstein with enclosing organic matter. Mixtures of coal + minor tonstein that occur within 20 mm of contacts are consistently enriched in some elements relative to either tonstein or nearby coal (U, Cu), or relative to calculated mixtures of tonstein and coal in their measured proportions (Th, Y, REE, Pb, Ba, V, Ti). Direct observations by fission-track radiography and electron microprobe indicate a preference of U and Fe for the organic component of mixtures. Metal fixation is probably by adsorption on insoluble organic matter (humic acids), or by precipitation as minor sulphides in these low-sulphur coals.
","language":"English","publisher":"Wiley","doi":"10.1111/j.1365-3091.1985.tb00471.x","issn":"00370746","usgsCitation":"Zielinski, R.A., 1985, Element mobility during alteration of silicic ash to kaolinite - A study of tonstein: Sedimentology, v. 32, no. 4, p. 567-579, https://doi.org/10.1111/j.1365-3091.1985.tb00471.x.","productDescription":"13 p.","startPage":"567","endPage":"579","costCenters":[],"links":[{"id":222253,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United 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\"}}]}","volume":"32","issue":"4","noUsgsAuthors":false,"publicationDate":"2006-06-14","publicationStatus":"PW","scienceBaseUri":"505a08b7e4b0c8380cd51c36","contributors":{"authors":[{"text":"Zielinski, R. 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This activity has persisted for hundreds of thousands of years and is likely to continue. The Long Valley magma chamber had a volume approaching 3000 km3 prior to its climatic caldera-forming eruption 0.7 m.y. ago but has been reduced to less than a third of this volume by cooling, eruption, and crystallization. Seismic evidence indicates that the main mass of the present Long Valley magma chamber is about 10 km in diameter and that its roof is 8–10 km deep with smaller cupolas as shallow as 4–5 km. Although a chamber of this size is probably capable of producing an eruption approaching 30 km3 of lava, the record over the past 0.5 m.y. suggests that eruptions of 1 km3 or less are far more likely. Models proposed for the current ground uplift and seismicity within the caldera require inflation of 0.1–0.2 km3 by additional magma since mid-1979, and some models suggest that inflation was accompanied by injection of a thin dike or dikes (probably of silicic magma) into the ring fracture zone beneath the south moat. Several of the M 5.8–6.2 earthquakes that occurred in the region beginning in 1978 had non-double-couple focal mechanisms. Whether these unusual mechanisms indicate injection of mafic (low-viscosity) magma at midcrustal depths in the Sierra Nevada block south of the caldera remains debatable. Studies of calderas of various ages throughout the world indicate that episodes of unrest are relatively common and do not invariably culminate in eruptions. Although current unrest is concentrated in the south moat of Long Valley caldera, the Inyo/Mono Craters probably hold a greater potential for producing an eruption in the foreseeable future. The Inyo/Mono Craters have erupted at 500-year intervals over the past 2000–3000 years, whereas the Long Valley magma chamber has erupted at about 200,000-year intervals over the past 700,000 years. In either case, a major earthquake near the caldera could strongly influence the course of volcanic activity.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB090iB13p11111","issn":"01480227","usgsCitation":"Hill, D., Bailey, R., and Ryall, A., 1985, Active tectonic and magmatic processes beneath Long Valley Caldera, eastern California: An overview: Journal of Geophysical Research Solid Earth, v. 90, no. B13, p. 11111-11120, https://doi.org/10.1029/JB090iB13p11111.","productDescription":"10 p.","startPage":"11111","endPage":"11120","costCenters":[],"links":[{"id":222074,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"90","issue":"B13","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"5059e6ade4b0c8380cd475a2","contributors":{"authors":[{"text":"Hill, D.P.","contributorId":27432,"corporation":false,"usgs":true,"family":"Hill","given":"D.P.","email":"","affiliations":[],"preferred":false,"id":363373,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bailey, R. A.","contributorId":87531,"corporation":false,"usgs":true,"family":"Bailey","given":"R. A.","affiliations":[],"preferred":false,"id":363374,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Ryall, A.S.","contributorId":7695,"corporation":false,"usgs":true,"family":"Ryall","given":"A.S.","email":"","affiliations":[],"preferred":false,"id":363372,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70012344,"text":"70012344 - 1985 - Simulated fissioning of uranium and testing of the fission-track dating method","interactions":[],"lastModifiedDate":"2013-03-06T20:03:53","indexId":"70012344","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2913,"text":"Nuclear Tracks and Radiation Measurements (1982)","active":true,"publicationSubtype":{"id":10}},"title":"Simulated fissioning of uranium and testing of the fission-track dating method","docAbstract":"A computer program (FTD-SIM) faithfully simulates the fissioning of 238U with time and 235U with neutron dose. The simulation is based on first principles of physics where the fissioning of 238U with the flux of time is described by Ns = ??f 238Ut and the fissioning of 235U with the fluence of neutrons is described by Ni = ??235U??. The Poisson law is used to set the stochastic variation of fissioning within the uranium population. The life history of a given crystal can thus be traced under an infinite variety of age and irradiation conditions. A single dating attempt or up to 500 dating attempts on a given crystal population can be simulated by specifying the age of the crystal population, the size and variation in the areas to be counted, the amount and distribution of uranium, the neutron dose to be used and its variation, and the desired ratio of 238U to 235U. A variety of probability distributions can be applied to uranium and counting-area. The Price and Walker age equation is used to estimate age. The output of FTD-SIM includes the tabulated results of each individual dating attempt (sample) on demand and/or the summary statistics and histograms for multiple dating attempts (samples) including the sampling age. An analysis of the results from FTD-SIM shows that: (1) The external detector method is intrinsically more precise than the population method. (2) For the external detector method a correlation between spontaneous track count, Ns, and induced track count, Ni, results when the population of grains has a stochastic uranium content and/or when the counting areas between grains are stochastic. For the population method no correlation can exist. (3) In the external detector method the sampling distribution of age is independent of the number of grains counted. In the population method the sampling distribution of age is highly dependent on the number of grains counted. (4) Grains with zero-track counts, either in Ns or Ni, are in integral part of fissioning theory and under certain circumstances must be included in any estimate of age. (5) In estimating standard error of age the standard error of Ns and Ni and ?? must be accurately estimated and propagated through the age equation. Several statistical models are presently available to do so. ?? 1985.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Nuclear Tracks and Radiation Measurements (1982)","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier","doi":"10.1016/0735-245X(85)90126-7","issn":"0735245X","usgsCitation":"McGee, V., Johnson, N., and Naeser, C.W., 1985, Simulated fissioning of uranium and testing of the fission-track dating method: Nuclear Tracks and Radiation Measurements (1982), v. 10, no. 3, p. 365-379, https://doi.org/10.1016/0735-245X(85)90126-7.","startPage":"365","endPage":"379","numberOfPages":"15","costCenters":[],"links":[{"id":221817,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":268862,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0735-245X(85)90126-7"}],"volume":"10","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8fa8e4b08c986b319073","contributors":{"authors":[{"text":"McGee, V.E.","contributorId":36295,"corporation":false,"usgs":true,"family":"McGee","given":"V.E.","email":"","affiliations":[],"preferred":false,"id":363328,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Johnson, N.M.","contributorId":105429,"corporation":false,"usgs":true,"family":"Johnson","given":"N.M.","email":"","affiliations":[],"preferred":false,"id":363329,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Naeser, C. W.","contributorId":17582,"corporation":false,"usgs":true,"family":"Naeser","given":"C.","middleInitial":"W.","affiliations":[],"preferred":false,"id":363327,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70012342,"text":"70012342 - 1985 - The transverse and oblique cylindrical equal-area projection of the ellipsoid.","interactions":[],"lastModifiedDate":"2013-03-12T21:00:11","indexId":"70012342","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":797,"text":"Annals of the Association of American Geographers","active":true,"publicationSubtype":{"id":10}},"title":"The transverse and oblique cylindrical equal-area projection of the ellipsoid.","docAbstract":"The formulas for the ellipsoidal projection are derived for both forward and inverse computations and consist of modifying the formulas obtained by using the authalic sphere so that the scale along the central line of the projection is constant. Fourier series are used to eliminate recurring numerical integration and other lengthy trigonometric computations of co-ordinates.-from Author","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Annals of the Association of American Geographers","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1111/j.1467-8306.1985.tb00077.x","usgsCitation":"Snyder, J., 1985, The transverse and oblique cylindrical equal-area projection of the ellipsoid.: Annals of the Association of American Geographers, v. 75, no. 3, p. 431-442, https://doi.org/10.1111/j.1467-8306.1985.tb00077.x.","startPage":"431","endPage":"442","numberOfPages":"12","costCenters":[],"links":[{"id":222715,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":269222,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1111/j.1467-8306.1985.tb00077.x"}],"volume":"75","issue":"3","noUsgsAuthors":false,"publicationDate":"2010-03-15","publicationStatus":"PW","scienceBaseUri":"505bb13ae4b08c986b325285","contributors":{"authors":[{"text":"Snyder, J.P.","contributorId":79235,"corporation":false,"usgs":true,"family":"Snyder","given":"J.P.","email":"","affiliations":[],"preferred":false,"id":363325,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70012310,"text":"70012310 - 1985 - Solid state recording current meter conversion","interactions":[],"lastModifiedDate":"2016-07-27T10:48:44","indexId":"70012310","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Solid state recording current meter conversion","docAbstract":"The authors describe the conversion of an Endeco-174 current meter to a solid-state recording current meter. A removable solid-state module was designed to fit in the space originally occupied by an 8-track tape cartridge. The module contains a CPU and 128 kilobytes of nonvolatile CMOS memory. The solid-state module communicates with any terminal or computer using an RS-232C interface at 4800 baud rate. A primary consideration for conversion was to keep modifications of the current meter to a minimum. The communication protocol was designed to emulate the Endeco tape translation unit, thus the need for a translation unit was eliminated and the original data reduction programs can be used without any modification. After conversion, the data recording section of the current meter contains no moving parts; the storage capacity of the module is equivalent to that of the original tape cartridge.
","largerWorkTitle":"Oceans Conference Record (IEEE)","conferenceTitle":"Ocean Engineering and the Environment - Conference Record.","conferenceLocation":"San Diego, CA, USA","language":"English","publisher":"IEEE","publisherLocation":"New York, NY, USA","issn":"01977385","usgsCitation":"Cheng, R.T., and Wang, L., 1985, Solid state recording current meter conversion, in Oceans Conference Record (IEEE), San Diego, CA, USA, p. 752-754.","startPage":"752","endPage":"754","numberOfPages":"3","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":552,"text":"San Francisco Bay-Delta","active":false,"usgs":true},{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":221884,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505aaf6ae4b0c8380cd87592","contributors":{"authors":[{"text":"Cheng, Ralph T.","contributorId":69134,"corporation":false,"usgs":true,"family":"Cheng","given":"Ralph","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":363239,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wang, Lichen","contributorId":79622,"corporation":false,"usgs":true,"family":"Wang","given":"Lichen","email":"","affiliations":[],"preferred":false,"id":363240,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70012297,"text":"70012297 - 1985 - A comparison of several methods of solving nonlinear regression groundwater flow problems","interactions":[],"lastModifiedDate":"2018-02-12T18:15:43","indexId":"70012297","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","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 comparison of several methods of solving nonlinear regression groundwater flow problems","docAbstract":"Computational efficiency and computer memory requirements for four methods of minimizing functions were compared for four test nonlinear-regression steady state groundwater flow problems. The fastest methods were the Marquardt and quasi-linearization methods, which required almost identical computer times and numbers of iterations; the next fastest was the quasi-Newton method, and last was the Fletcher-Reeves method, which did not converge in 100 iterations for two of the problems. The fastest method per iteration was the Fletcher-Reeves method, and this was followed closely by the quasi-Newton method. The Marquardt and quasi-linearization methods were slower. For all four methods the speed per iteration was directly related to the number of parameters in the model. However, this effect was much more pronounced for the Marquardt and quasi-linearization methods than for the other two. Hence the quasi-Newton (and perhaps Fletcher-Reeves) method might be more efficient than either the Marquardt or quasi-linearization methods if the number of parameters in a particular model were large, although this remains to be proven. The Marquardt method required somewhat less central memory than the quasi-linearization metilod for three of the four problems. For all four problems the quasi-Newton method required roughly two thirds to three quarters of the memory required by the Marquardt method, and the Fletcher-Reeves method required slightly less memory than the quasi-Newton method. Memory requirements were not excessive for any of the four methods.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/WR021i010p01525","usgsCitation":"Cooley, R.L., 1985, A comparison of several methods of solving nonlinear regression groundwater flow problems: Water Resources Research, v. 21, no. 10, p. 1525-1538, https://doi.org/10.1029/WR021i010p01525.","productDescription":"14 p.","startPage":"1525","endPage":"1538","costCenters":[],"links":[{"id":222650,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"21","issue":"10","noUsgsAuthors":false,"publicationDate":"2008-01-08","publicationStatus":"PW","scienceBaseUri":"5059e372e4b0c8380cd46021","contributors":{"authors":[{"text":"Cooley, Richard L.","contributorId":8831,"corporation":false,"usgs":true,"family":"Cooley","given":"Richard","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":363209,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70012288,"text":"70012288 - 1985 - LORAN-C LATITUDE-LONGITUDE CONVERSION AT SEA: PROGRAMMING CONSIDERATIONS.","interactions":[],"lastModifiedDate":"2012-03-12T17:19:04","indexId":"70012288","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"LORAN-C LATITUDE-LONGITUDE CONVERSION AT SEA: PROGRAMMING CONSIDERATIONS.","docAbstract":"Comparisons are made of the precision of arc-length routines as computer precision is reduced. Overland propagation delays are discussed and illustrated with observations from offshore New England. Present practice of LORAN-C error budget modeling is then reviewed with the suggestion that additional terms be considered in future modeling. Finally, some detailed numeric examples are provided to help with new computer program checkout.","conferenceTitle":"Proceedings of the National Technical Conference - Institute of Navigation.","conferenceLocation":"San Diego, CA, USA","language":"English","publisher":"Inst of Navigation","publisherLocation":"Washington, DC, USA","usgsCitation":"McCullough, J.R., Irwin, B.J., and Bowles, R.M., 1985, LORAN-C LATITUDE-LONGITUDE CONVERSION AT SEA: PROGRAMMING CONSIDERATIONS., Proceedings of the National Technical Conference - Institute of Navigation., San Diego, CA, USA, p. 127-153.","startPage":"127","endPage":"153","numberOfPages":"27","costCenters":[],"links":[{"id":222471,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a40efe4b0c8380cd65176","contributors":{"authors":[{"text":"McCullough, James R.","contributorId":95619,"corporation":false,"usgs":true,"family":"McCullough","given":"James","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":363191,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Irwin, Barry J. birwin@usgs.gov","contributorId":3889,"corporation":false,"usgs":true,"family":"Irwin","given":"Barry","email":"birwin@usgs.gov","middleInitial":"J.","affiliations":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":true,"id":363189,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bowles, Robert M.","contributorId":26447,"corporation":false,"usgs":true,"family":"Bowles","given":"Robert","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":363190,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70012265,"text":"70012265 - 1985 - The Dunbar Gneiss-granitoid dome: Implications for early Proterozoic tectonic evolution of northern Wisconsin","interactions":[],"lastModifiedDate":"2024-01-03T00:52:03.874553","indexId":"70012265","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1786,"text":"Geological Society of America Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"The Dunbar Gneiss-granitoid dome: Implications for early Proterozoic tectonic evolution of northern Wisconsin","docAbstract":"The Dunbar dome in northeastern Wisconsin is a critical structural feature in the early Proterozoic Penokean orogen. It provides exposures of gneisses (Dunbar Gneiss) that structurally underlie the voluminous metavolcanic rocks of northeastern Wisconsin, and exposures of abundant granitoid rocks ranging from tonalite to granite. The granitoid rocks cut both the gneisses in the core and the supracrustal (cover) metavolcanic rocks and were emplaced essentially along the core-cover boundary. The Dunbar Gneiss is calc-alkaline and was derived from volcanic and intrusive rocks of intermediate composition. The various intrusive rocks have calcic, calc-alkaline, and alkali to alkali-calcic compositions, and they progress with time to more SiO2 and K2-rich compositions. U-Pb zircon ages indicate that accumulation of the layered rocks in the core and cover, deformation and metamorphism, and intrusion of the granitoid rocks spanned a relatively short time, ∼1865–1835 Ma.
We interpret the dome as being a large-scale, fold-interference structure resulting from polydeformation modified by diapirism. Northeast-oriented folds (F3) and a related mylonitic foliation (S3), nearly confined to the dome, are superposed on northwest-oriented folds (F2) that developed during regional deformation. In the core-cover boundary, these structures are obliterated by a zone of intense deformation—a mylonitic foliation and a steeply plunging stretching lineation—as much as 500 m wide, which we interpret as resulting from diapirism. Metamorphic zoning is concentric: amphibolite facies in inner parts of the mantle and greenschist facies in the outer part of the mantle.
The Wisconsin magmatic terrane, as represented by the rocks in the Dunbar dome, differs from the epicratonic, early Proterozoic sedimentary-volcanic sequence (Marquette Range Supergroup) in Michigan, to the north, in stratigraphy, structure, and volume and composition of igneous rocks. Whereas the basalts in northern Michigan are compositionally similar to continental rift basalts, the volcanic rocks in the Dunbar dome have over-all island-arc compositional affinities. The over-all calc-alkaline compositions of the intrusive rocks are similar to those in magmatic arcs formed at convergent plate-margin settings. Accordingly, we interpret the Wisconsin magmatic terrane as an oceanic-arc complex that was sutured to the North American continent during development of the Penokean orogen. Similar interpretations based on broad regional observations have been proposed previously.
A reinterpretation of the origin of subsurface rocks in southwestern Virginia and southeastern Kentucky suggests that, contrary to commonly accepted ideas, the Mississippian-Pennsylvanian Systemic boundary is an unconformity and the Lower Pennsylvanian quartz arenite sequences were deposited in a fluvial environment. Because Pennsylvanian strata of the Pocahontas and Lee Formations appear to have been deposited at the same time in adjacent valleys, the Pocahontas, which generally has been considered to be older and to underlie the Lee, is considered here to be equivalent to the basal part of the Middlesboro Member of the Lee Formation.
Mechanistic roles of soil humus and soil minerals and their contributions to soil sorption of nonionic organic compounds from aqueous and organic solutions are illustrated. Parathion and lindane are used as model solutes on two soils that differ greatly in their humic and mineral contents. In aqueous systems, observed sorptive characteristics suggest that solute partitioning into the soil-humic phase is the primary mechanism of soil uptake. By contrast, data obtained from organic solutions on dehydrated soil partitioning into humic phase and adsorption by soil minerals is influenced by the soil-moisture content and by the solvent medium from which the solute is sorbed.
","language":"English","publisher":"Elsevier","doi":"10.1016/0146-6380(85)90045-2","issn":"01466380","usgsCitation":"Chiou, C.T., Shoup, T., and Porter, P., 1985, Mechanistic roles of soil humus and minerals in the sorption of nonionic organic compounds from aqueous and organic solutions: Organic Geochemistry, v. 8, no. 1, p. 9-14, https://doi.org/10.1016/0146-6380(85)90045-2.","productDescription":"6 p.","startPage":"9","endPage":"14","numberOfPages":"6","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":218613,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"8","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5374e4b0c8380cd6cac7","contributors":{"authors":[{"text":"Chiou, C. T.","contributorId":97080,"corporation":false,"usgs":true,"family":"Chiou","given":"C.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":357440,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Shoup, T.D.","contributorId":12614,"corporation":false,"usgs":true,"family":"Shoup","given":"T.D.","email":"","affiliations":[],"preferred":false,"id":357438,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Porter, P.E.","contributorId":31109,"corporation":false,"usgs":true,"family":"Porter","given":"P.E.","email":"","affiliations":[],"preferred":false,"id":357439,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":28861,"text":"wri854055 - 1985 - Investigation of selected streamflow characteristics of the Alabama River upstream from Selma, Alabama","interactions":[],"lastModifiedDate":"2022-06-06T17:50:01.378241","indexId":"wri854055","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"85-4055","title":"Investigation of selected streamflow characteristics of the Alabama River upstream from Selma, Alabama","docAbstract":"Available data for floods in the vicinity of Montgomery since the late 1800 's indicate that the flood of 1886 is the highest since settlement of the area in 1814. Profiles for floods in 1948, 1961, 1976, and 1979 were defined using floodmarks and recorded peak stages at gaging stations at Selma and Montgomery. The floods in 1948 and 1961 occurred before construction of Robert F. Henry Lock and Dam (formerly Jones Bluff Lock and Dam and Millers Ferry Lock and Dam). Considerable water-surface differences are indicated between the profiles for periods before and after construction of the dams. The investigation included a step-backwater model to reproduce profiles based on the actual flood profiles. After the actual flood profiles were reproduced, the model was used to compute additional profiles showing the effects of varying tributary inflow. The profiles were computed for discharges ranging from 80,000 ft3/s to 500 ,000 ft3/s. Stage-discharge relations were then developed for five sites upstream from Selma. Discharge coefficient curves for prevalent types of flow over the spillway at Robert F. Henry Lock and Dam were developed using discharges obtained from current-meter measurements and standard discharge equations for flow through gate-controlled spillways. (USGS)","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/wri854055","collaboration":"Prepared in cooperation with the U.S. Army Corps of Engineers, Mobile District","usgsCitation":"Nelson, G.H., Ming, C.O., and Psinakis, W.L., 1985, Investigation of selected streamflow characteristics of the Alabama River upstream from Selma, Alabama: U.S. Geological Survey Water-Resources Investigations Report 85-4055, vi, 44 p., https://doi.org/10.3133/wri854055.","productDescription":"vi, 44 p.","costCenters":[],"links":[{"id":401757,"rank":6,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1985/4055/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":57740,"rank":403,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/wri/1985/4055/plate-4.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":57739,"rank":402,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/wri/1985/4055/plate-3.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":57737,"rank":400,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/wri/1985/4055/plate-1.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":159334,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1985/4055/report-thumb.jpg"},{"id":57738,"rank":401,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/wri/1985/4055/plate-2.pdf","linkFileType":{"id":1,"text":"pdf"}}],"country":"United States","state":"Alabama","city":"Selma","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -87.154541015625,\n 32.22906629627297\n ],\n [\n -86.22894287109375,\n 32.22906629627297\n ],\n [\n -86.22894287109375,\n 32.51207789841144\n ],\n [\n -87.154541015625,\n 32.51207789841144\n ],\n [\n -87.154541015625,\n 32.22906629627297\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4783e4b07f02db483979","contributors":{"authors":[{"text":"Nelson, G. H. Jr.","contributorId":23562,"corporation":false,"usgs":true,"family":"Nelson","given":"G.","suffix":"Jr.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":200521,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ming, C. O.","contributorId":9266,"corporation":false,"usgs":true,"family":"Ming","given":"C.","email":"","middleInitial":"O.","affiliations":[],"preferred":false,"id":200520,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Psinakis, W. L.","contributorId":104074,"corporation":false,"usgs":true,"family":"Psinakis","given":"W.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":200522,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":29912,"text":"wri854087 - 1985 - Ground-water flow in the Prairie du Chien-Jordan aquifer related to contamination by coal-tar derivatives, St. Louis Park, Minnesota","interactions":[],"lastModifiedDate":"2023-03-13T19:17:59.193897","indexId":"wri854087","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"85-4087","title":"Ground-water flow in the Prairie du Chien-Jordan aquifer related to contamination by coal-tar derivatives, St. Louis Park, Minnesota","docAbstract":"A three-dimensional, ground-water-flow model of the Prairie du Chien-Jordan aquifer and associated hydrogeologic units was developed to evaluate the movement of coal-tar derivatives from a coal-tar distillation and wood-preserving plant in St. Louis Park, Minnesota. A finite-difference grid was superimposed on the modeled area, which includes most of eastern Hennepin County. The individual cells are 400-foot squares in the center of the grid (St. Louis Park area); the cells increase in dimension toward the outside limits of the grid. Five geologic units are represented by four layers in the model. These units include the Jordan Sandstone, the Prairie du Chien Group (dolomite and sandy dolomite), the basal confining unit of the St. Peter Sandstone (silty and sandy shale), the St. Peter Sandstone, and glacial deposits in bedrock valleys.
The model was calibrated for steady-state conditions for a period before significant ground-water development (1885-1930) and for a period of significant pumping stress (winter conditions, 1970 fs). A transient calibration was accomplished by simulation of a period during which seasonal changes in potentiometric head in the Prairie du Chien-Jordan aquifer were significant (1977-80). Sensitivity testing indicated that leakage to the upper model layer and the vertical hydraulic conductivity of the basal confining unit of the St. Peter Sandstone were the model hydrologic properties which, when changed, resulted in the greatest changes in model-calculated water levels. The calibrated model generally calculates water levels that are within 10 feet of measured values.
Model simulations indicate that the potentiometric surface of the Prairie du Chien-Jordan aquifer would be raised by as much as 3 feet in the area of the plant site by water introduced into the aquifer through wells open to more than one aquifer system. The cones of impression created at these wells could have a significant impact on the transport of contaminants in the Prairie du Chien-Jordan.
The presence of coal-tar derivatives in the aquifer has been difficult to explain in wells located upgradient from the plant site to the north, west, and southwest. Simulations suggest that, during periods of heavy withdrawal from certain of these wells (SLP10, SLP15, and SLP5), local hydraulic gradients may have been altered, resulting in the potential for the movement of contaminants from the area of the plant site to the wells. Cones of impression at multiaquifer wells near the plant site contributed to the alteration of local gradients.
Simulation of a proposed gradient-control plan, in which lateral homogeneity and isotropy of individual hydro geologic units was assumed, indicates that the actions would be effective in limiting expansion of the contaminated volume in the Prairie du Chien-Jordan aquifer. The plan includes the control of withdrawal from five wells. The simulations also show, however, that modelcalculated potentiometric surfaces are sensitive to changes in withdrawal rates at wells not intended to be under the control of the plan. Management of discharge from these wells also will be important to overall effectiveness of the remedial-action plan.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"St. Paul, MN","doi":"10.3133/wri854087","usgsCitation":"Stark, J., and Hult, M.F., 1985, Ground-water flow in the Prairie du Chien-Jordan aquifer related to contamination by coal-tar derivatives, St. Louis Park, Minnesota: U.S. Geological Survey Water-Resources Investigations Report 85-4087, v, 57 p., https://doi.org/10.3133/wri854087.","productDescription":"v, 57 p.","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":392,"text":"Minnesota Water Science Center","active":true,"usgs":true}],"links":[{"id":414036,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_36260.htm","linkFileType":{"id":5,"text":"html"}},{"id":119515,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1985/4087/report-thumb.jpg"},{"id":58730,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1985/4087/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"country":"United States","state":"Minnesota","city":"St. Louis Park","otherGeospatial":"Prairie du Chien-Jordan aquifer","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -93.167,\n 45.083\n ],\n [\n -93.583,\n 45.083\n ],\n [\n -93.583,\n 44.783\n ],\n [\n -93.167,\n 44.783\n ],\n [\n -93.167,\n 45.083\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4aafe4b07f02db66cd74","contributors":{"authors":[{"text":"Stark, J. R.","contributorId":100406,"corporation":false,"usgs":true,"family":"Stark","given":"J. R.","affiliations":[],"preferred":false,"id":202343,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hult, M. F.","contributorId":29817,"corporation":false,"usgs":true,"family":"Hult","given":"M.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":202342,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":30582,"text":"wri854292 - 1985 - Limnology of nine small lakes, Matanuska-Susitna Borough, Alaska, and the survival and growth rates of rainbow trout","interactions":[],"lastModifiedDate":"2023-03-14T21:16:27.755353","indexId":"wri854292","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"85-4292","title":"Limnology of nine small lakes, Matanuska-Susitna Borough, Alaska, and the survival and growth rates of rainbow trout","docAbstract":"The survival and growth rates of rainbow trout (Salmo gairdnieri) were concurrently measured with selected limnological characteristics in nine small (surface area < 25 sq hectometers) lakes in the Matanuska-Susitna Borough. The project goal was to develop empirical models for predicting rainbow trout growth rates from the following variables: total phosphorus concentration, chlorophyll a concentration, Secchi disc transparency, or the morphoedaphic index--a means of characterizing potential biological productivity. No suitable model could be developed from the data collected during 1982 and 1983. The lack of significant correlation was attributed in part to the wide variation in survival of rainbow trout. Winterkills, caused by severe depletion of dissolved oxygen, were suspected in four of the lakes. Varied levels of fishing pressure and competition with threespine stickleback (Gasterosteus aculeatus) also influenced survival of rainbow trout but their effects were overshadowed by winterkill. Predictive capability was also reduced because of inconsistencies in rankings generated by each of the four limnological variables chosen as indicators of potential biological productivity. A lake ranked low in productivity by one variable was commonly ranked high in productivity by another variable. The survivability of rainbow trout stocked in lakes such as these nine may be a more important indicator of potential biomass production than are indicators of lake fertility. Assessments of a lake 's susceptibility to winterkill and the degree of competition with threespine stickleback are suggested as important topics for additional research.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/wri854292","usgsCitation":"Woods, P.F., 1985, Limnology of nine small lakes, Matanuska-Susitna Borough, Alaska, and the survival and growth rates of rainbow trout: U.S. Geological Survey Water-Resources Investigations Report 85-4292, iv, 32 p., https://doi.org/10.3133/wri854292.","productDescription":"iv, 32 p.","costCenters":[],"links":[{"id":414141,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_36430.htm","linkFileType":{"id":5,"text":"html"}},{"id":59341,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1985/4292/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":123988,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1985/4292/report-thumb.jpg"}],"country":"United States","state":"Alaska","otherGeospatial":"Matanuska-Susitna Borough, Alaska","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -149.817,\n 61.833\n ],\n [\n -149.817,\n 61.45\n ],\n [\n -148.267,\n 61.45\n ],\n [\n -148.267,\n 61.833\n ],\n [\n -149.817,\n 61.833\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b15e4b07f02db6a50f9","contributors":{"authors":[{"text":"Woods, P. F.","contributorId":97509,"corporation":false,"usgs":true,"family":"Woods","given":"P.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":203490,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70197496,"text":"70197496 - 1985 - Paleomagnetism and geology of Eocene volcanic rocks of southwest Washington, implications for mechanisms of tectonic rotation","interactions":[],"lastModifiedDate":"2018-06-07T15:29:48","indexId":"70197496","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2312,"text":"Journal of Geophysical Research","active":true,"publicationSubtype":{"id":10}},"title":"Paleomagnetism and geology of Eocene volcanic rocks of southwest Washington, implications for mechanisms of tectonic rotation","docAbstract":"We carried out an extensive paleointensity study of the 15.5±0.3 m.y. Miocene reversed‐to‐normal polarity transition recorded in lava flows from Steens Mountain (south central Oregon). One hundred eighty‐five samples from the collection whose paleodirectional study is reported by Mankinen et al. (this issue) were chosen for paleointensity investigations because of their low viscosity index, high Curie point and reversibility, or near reversibility, of the strong field magnetization curve versus temperature. Application of the Thellier stepwise double heating method was very successful, yielding 157 usable paleointensity estimates corresponding to 73 distinct lava flows. After grouping successive lava flows that did not differ significantly in direction and intensity, we obtained 51 distinguishable, complete field vectors of which 10 are reversed, 28 are transitional, and 13 are normal. The record is complex, quite unlike that predicted by simple flooding or standing nondipole field models. It begins with an estimated several thousand years of reversed polarity with an average intensity of 31.5±8.5 μT, about one third lower than the expected Miocene intensity. This difference is interpreted as a long‐term reduction of the dipole moment prior to the reversal. When site directions and intensities are considered, truly transitional directions and intensities appear almost at the same time at the beginning of the transition, and they disappear simultaneously at the end of the reversal. Large deviations in declination occur during this approximately 4500±1000 year transition period that are compatible with roughly similar average magnitudes of zonal and nonzonal field components at the site. The transitional intensity is generally low, with an average of 10.9±4.9 μT for directions more than 45° away from the dipole field and a minimum of about 5 μT. The root‐mean‐square of the three field components X, Y, and Z are of the same order of magnitude for the transitional field and the historical nondipole field at the site latitude. However, a field intensity increase to pretransitional values occurs when the field temporarily reaches normal directions, which suggests that dipolar structure could have been briefly regenerated during the transition in an aborted attempt to reestablish a stationary field. Changes in the field vector are progressive but jerky, with at least two, and possibly three, large swings at astonishingly high rates. Each of those transitional geomagnetic impulses occurs when the field intensity is low (less than 10 μT) and is followed by an interval of directional stasis during which the magnitude of the field increases greatly. For the best documented geomagnetic impulse the rapid directional change corresponds to a vectorial intensity change of 6700±2700 nT yr−1, which is about 15–50 times larger than the maximum rate of change of the nondipole field observed during the last centuries. The occurrence of geomagnetic impulses seems to support reversal models assuming an increase in the level of turbulence within the liquid core during transitions. The record closes with an estimated several thousand years of normal polarity with an average intensity of 46.7±20.1 μT, agreeing with the expected Miocene value. However, the occurrence of rather large and apparently rapid intensity fluctuations accompanied by little change in direction suggests that the newly reestablished dipole was still somewhat unstable.
","language":"English","publisher":"AGU","doi":"10.1029/JB090iB12p10417","usgsCitation":"Prevot, M., Mankinen, E.A., Coe, R.S., and Gromme, C.S., 1985, The Steens Mountain (Oregon) geomagnetic polarity transition, 2. Field intensity variations and discussion of reversal models: Journal of Geophysical Research B: Solid Earth, v. 90, no. B12, p. 10417-10448, https://doi.org/10.1029/JB090iB12p10417.","productDescription":"32 p.","startPage":"10417","endPage":"10448","costCenters":[{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true}],"links":[{"id":354331,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"90","issue":"B12","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"5aff3a76e4b0da30c1bfd9fd","contributors":{"authors":[{"text":"Prevot, M.","contributorId":75679,"corporation":false,"usgs":true,"family":"Prevot","given":"M.","email":"","affiliations":[],"preferred":false,"id":735876,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Mankinen, Edward A. 0000-0001-7496-2681 emank@usgs.gov","orcid":"https://orcid.org/0000-0001-7496-2681","contributorId":1054,"corporation":false,"usgs":true,"family":"Mankinen","given":"Edward","email":"emank@usgs.gov","middleInitial":"A.","affiliations":[{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true}],"preferred":true,"id":735877,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Coe, Robert S.","contributorId":20477,"corporation":false,"usgs":true,"family":"Coe","given":"Robert","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":735878,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Gromme, C. Sherman","contributorId":22236,"corporation":false,"usgs":true,"family":"Gromme","given":"C.","email":"","middleInitial":"Sherman","affiliations":[],"preferred":false,"id":735879,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70135805,"text":"70135805 - 1985 - Coupling of ocean bottom seismometers to sediment: Results of tests with the U.S. Geological Survey ocean bottom seismometer","interactions":[],"lastModifiedDate":"2023-10-28T15:44:56.081191","indexId":"70135805","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1135,"text":"Bulletin of the Seismological Society of America","onlineIssn":"1943-3573","printIssn":"0037-1106","active":true,"publicationSubtype":{"id":10}},"title":"Coupling of ocean bottom seismometers to sediment: Results of tests with the U.S. Geological Survey ocean bottom seismometer","docAbstract":"The response of an ocean bottom seismometer (OBS) to a transient pull that excites the natural OBS-sediment coupling resonance can be modeled as a mass-spring-dashpot system in which the resonant frequency and damping are functions of instrument mass and bearing radius and of the physical properties of the sediment (primarily the shear modulus). For the very soft sediments sometimes found on the sea floor, this resonance may be within the main frequency band of interest (2 to 15 Hz) for many common instrument configurations. To test the model and to find an anchor that would shift the coupling resonance to a higher frequency and decrease its amplitude, we conducted a series of tests which measured the response of the vertical and horizontal components of the U.S. Geological Survey OBS to transient pulls as a function of anchor configuration and sediment properties. The tested anchors included a concrete “flowerpot,” a tripod, a plate, and a perforated plate. Sites were on soft, organic-rich ooze and on firm sand. Several small shots were also fired at the ooze site in order to compare the response of the plate and “flowerpot” anchors to seismic signals. For a given anchor at a given site, the observed response was very repeatable. We found that the model predicts the vertical coupling response quite well and that good vertical coupling can be achieved with the plate or perforated-plate anchors. The response to the horizontal pulls, however, was similar and resonant for all anchors.
","language":"English","publisher":"Seismological Society of America","doi":"10.1785/BSSA0750010271","usgsCitation":"Trehu, A.M., 1985, Coupling of ocean bottom seismometers to sediment: Results of tests with the U.S. Geological Survey ocean bottom seismometer: Bulletin of the Seismological Society of America, v. 75, no. 1, p. 271-289, https://doi.org/10.1785/BSSA0750010271.","productDescription":"19 p.","startPage":"271","endPage":"289","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":186,"text":"Coastal and Marine Geology Program","active":true,"usgs":true}],"links":[{"id":296756,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"75","issue":"1","noUsgsAuthors":false,"publicationDate":"1985-02-01","publicationStatus":"PW","scienceBaseUri":"5492b73ee4b00eda8915ad0c","contributors":{"authors":[{"text":"Trehu, Anne M.","contributorId":49884,"corporation":false,"usgs":false,"family":"Trehu","given":"Anne","email":"","middleInitial":"M.","affiliations":[{"id":6680,"text":"Oregon State University","active":true,"usgs":false}],"preferred":false,"id":536879,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70137246,"text":"70137246 - 1985 - Use of strontium isotopes to constrain the timing and mode of dolomitization of upper Cenozoic sediments in a core from San Salvador, Bahamas","interactions":[],"lastModifiedDate":"2024-01-30T00:51:56.949725","indexId":"70137246","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1796,"text":"Geology","active":true,"publicationSubtype":{"id":10}},"title":"Use of strontium isotopes to constrain the timing and mode of dolomitization of upper Cenozoic sediments in a core from San Salvador, Bahamas","docAbstract":"The 87Sr/86Sr ratios and the activity ratios of 234U/238U and 230Th/238U have been measured in dolomites from a 168-m-deep core taken on the island of San Salvador, Bahamas. These data suggest two periods of dolomitization. The first episode dolomitized Miocene age sediments during the latest Miocene, and the second dolomitized the Pliocene portion of the core and was still active as recently as 150 ka. The late timing of the second episode argues against penecontemporaneous models of dolomitization for the Pliocene sediments. Instead, dolomitization is favored either as a result of mixing-zone development during the large Pleistocene sea-level changes or by movement of seawater through the platform.
","language":"English","publisher":"Geological Society of America","doi":"10.1130/0091-7613(1987)15<262:UOSITC>2.0.CO;2","usgsCitation":"Swart, P.K., Ruiz, J., and Holmes, C.W., 1985, Use of strontium isotopes to constrain the timing and mode of dolomitization of upper Cenozoic sediments in a core from San Salvador, Bahamas: Geology, v. 15, no. 3, p. 262-265, https://doi.org/10.1130/0091-7613(1987)15<262:UOSITC>2.0.CO;2.","productDescription":"4 p.","startPage":"262","endPage":"265","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":186,"text":"Coastal and Marine Geology Program","active":true,"usgs":true}],"links":[{"id":296990,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Bahamas","otherGeospatial":"San Salvador Island","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -74.3115234375,\n 21.022982546427436\n ],\n [\n -72.2021484375,\n 22.63429269379353\n ],\n [\n -77.71728515624999,\n 27.527758206861886\n ],\n [\n -80.13427734374999,\n 25.403584973186703\n ],\n [\n -74.3115234375,\n 21.022982546427436\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"15","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"54dd2c7de4b08de9379b383b","contributors":{"authors":[{"text":"Swart, Peter K.","contributorId":96832,"corporation":false,"usgs":false,"family":"Swart","given":"Peter","email":"","middleInitial":"K.","affiliations":[{"id":5112,"text":"University of Miami","active":true,"usgs":false}],"preferred":false,"id":537557,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ruiz, Joaquin","contributorId":87967,"corporation":false,"usgs":false,"family":"Ruiz","given":"Joaquin","email":"","affiliations":[{"id":7042,"text":"University of Arizona","active":true,"usgs":false}],"preferred":false,"id":537558,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Holmes, Charles W.","contributorId":31071,"corporation":false,"usgs":true,"family":"Holmes","given":"Charles","email":"","middleInitial":"W.","affiliations":[{"id":218,"text":"Denver Federal Center","active":false,"usgs":true}],"preferred":false,"id":537559,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ]}