Descriptive and grade/tonnage models have recently been built for many types of deposits. Such models consist of descriptions of mineralogy, host rocks, ore textures, controls, alteration, geochemical signatures, age, and tectonic settings, together with statistical models of grades, tonnages, and contained metal of deposits of each type. The models are used to identify areas that may contain undiscovered deposits of given types, to convey to non-geologists an idea of the importance of such deposits, and to test and refine classifications of mineral deposits.
Descriptive and grade/tonnage models have recently been built for five types of primary tin deposits: rhyolite-hosted such as in Mexico; hydrothermal lodes such as in Cornwall, England, and the Herberton district, Queensland; replacement (or exhalative?) such as Renison Bell, Tasmania; skarn such as at Lost River, Alaska; and greisen such as in the Erzgebirge. Analyses of frequency distributions of tonnage, contained metal, tin grades and the relationships between these variables show that the deposits fall into four well-defined domains that have definite geological characteristics. Rhyolite-hosted, or Mexican, deposits contain a median of 4 t of tin and have a median grade of 0.4% Sn. Hydrothermal lode deposits have the highest grades. Half of such deposits have grades over 1.0% Sn, and the majority contain more than 1,000 t Sn. Large hydrothermal vein deposits contain more than 50,000 t Sn. Replacement (or exhalative?) deposits contain the largest amount of tin (median = 40,000 t). They are only of slightly lower grade (median = 0.80% Sn) than the hydrothermal lodes. Greisen or stockwork deposits have larger tonnages than replacement deposits, but contain less tin (median = 25,000 t).They are also of much lower grade (median = 0.3% Sn). Though grades and tonnages are available for only four skarn deposits, they appear to be more like greisen deposits than replacement deposits when compared using grades, tonnage and contained tin.
Although these individual models of primary tin deposits must be regarded as preliminary because of the relatively small number of deposits upon which they are built, they clearly demonstrate differences among types and provide basic information that can be useful in making decisions about exploration strategy, land classification, and tin supply.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Geology of tin deposits in Asia and the Pacific","language":"English","publisher":"Springer","doi":"10.1007/978-3-642-72765-8_4","usgsCitation":"Menzie, W., Reed, B., and Singer, D.A., 1988, Models of grades and tonnages of some lode tin deposits, chap. of Geology of tin deposits in Asia and the Pacific, p. 73-88, https://doi.org/10.1007/978-3-642-72765-8_4.","productDescription":"16 p.","startPage":"73","endPage":"88","costCenters":[{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true}],"links":[{"id":354465,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5b15af92e4b092d9651e2330","contributors":{"authors":[{"text":"Menzie, W. D.","contributorId":52916,"corporation":false,"usgs":true,"family":"Menzie","given":"W. D.","affiliations":[],"preferred":false,"id":736462,"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":736463,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Singer, Donald A. dsinger@usgs.gov","contributorId":5601,"corporation":false,"usgs":true,"family":"Singer","given":"Donald","email":"dsinger@usgs.gov","middleInitial":"A.","affiliations":[],"preferred":true,"id":736464,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70014370,"text":"70014370 - 1988 - The response of creeping parts of the San Andreas fault to earthquakes on nearby faults: Two examples","interactions":[],"lastModifiedDate":"2012-03-12T17:19:31","indexId":"70014370","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3209,"text":"Pure and Applied Geophysics PAGEOPH","active":true,"publicationSubtype":{"id":10}},"title":"The response of creeping parts of the San Andreas fault to earthquakes on nearby faults: Two examples","docAbstract":"Rates of shallow slip on creeping sections of the San Andreas fault have been perturbed on a number of occasions by earthquakes occurring on nearby faults. One example of such perturbations occurred during the 26 January 1986 magnitude 5.3 Tres Pinos earthquake located about 10 km southeast of Hollister, California. Seven creepmeters on the San Andreas fault showed creep steps either during or soon after the shock. Both left-lateral (LL) and right-lateral (RL) steps were observed. A rectangular dislocation in an elastic half-space was used to model the coseismic fault offset at the hypocenter. For a model based on the preliminary focal mechanism, the predicted changes in static shear stress on the plane of the San Andreas fault agreed in sense (LL or RL) with the observed slip directions at all seven meters; for a model based on a refined focal mechanism, six of the seven meters showed the correct sense of motion. Two possible explanations for such coseismic and postseismic steps are (1) that slip was triggered by the earthquake shaking or (2) that slip occurred in response to the changes in static stress fields accompanying the earthquake. In the Tres Pinos example, the observed steps may have been of both the triggered and responsive kinds. A second example is provided by the 2 May 1983 magnitude 6.7 Coalinga earthquake, which profoundly altered slip rates at five creepmeters on the San Andreas fault for a period of months to years. The XMM1 meter 9 km northwest of Parkfield, California recorded LL creep for more than a year after the event. To simulate the temporal behavior of the XMM1 meter and to view the stress perturbation provided by the Coalinga earthquake in the context of steady-state deformation on the San Andreas fault, a simple time-evolving dislocation model was constructed. The model was driven by a single long vertical dislocation below 15 km in depth, that was forced to slip at 35 mm/yr in a RL sense. A dislocation element placed in the seismogenic layer under XMM1 was given a finite breaking strength of sufficient magnitude to produce a Parkfield-like earthquake every 22 years. When stress changes equivalent to a Coalinga earthquake were superposed on the model running in a steady state mode, the effect was to make a segment under XMM1, that could slip in a linear viscous fashion, creep LL and to delay the onset of the next Parkfield-like earthquake by a year or more. If static stress changes imposed by earthquakes off the San Andreas can indeed advance or delay earthquakes on the San Andreas by months or years, then such changes must be considered in intermediate-term prediction efforts. ?? 1988 Birkha??user Verlag.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Pure and Applied Geophysics PAGEOPH","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisherLocation":"Birkha??user-Verlag","doi":"10.1007/BF00879014","issn":"00334553","usgsCitation":"Simpson, R., Schulz, S., Dietz, L., and Burford, R.O., 1988, The response of creeping parts of the San Andreas fault to earthquakes on nearby faults: Two examples: Pure and Applied Geophysics PAGEOPH, v. 126, no. 2-4, p. 665-685, https://doi.org/10.1007/BF00879014.","startPage":"665","endPage":"685","numberOfPages":"21","costCenters":[],"links":[{"id":205623,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF00879014"},{"id":225375,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"126","issue":"2-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505baf37e4b08c986b324633","contributors":{"authors":[{"text":"Simpson, R.W.","contributorId":76738,"corporation":false,"usgs":true,"family":"Simpson","given":"R.W.","email":"","affiliations":[],"preferred":false,"id":368237,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Schulz, S.S.","contributorId":6859,"corporation":false,"usgs":true,"family":"Schulz","given":"S.S.","email":"","affiliations":[],"preferred":false,"id":368234,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Dietz, L.D.","contributorId":50720,"corporation":false,"usgs":true,"family":"Dietz","given":"L.D.","email":"","affiliations":[],"preferred":false,"id":368235,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Burford, Robert O.","contributorId":52560,"corporation":false,"usgs":true,"family":"Burford","given":"Robert","middleInitial":"O.","affiliations":[],"preferred":false,"id":368236,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":25521,"text":"wri874281 - 1988 - Geohydrology and mathematical simulation of the Pajaro Valley aquifer system, Santa Cruz and Monterey Counties, California","interactions":[],"lastModifiedDate":"2023-04-10T20:42:41.472685","indexId":"wri874281","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"87-4281","title":"Geohydrology and mathematical simulation of the Pajaro Valley aquifer system, Santa Cruz and Monterey Counties, California","docAbstract":"Groundwater development has resulted in lowered water levels and seawater intrusion in the Pajaro Valley, California. An investigation was undertaken to describe the geohydrology of the groundwater flow system and to evaluate the response of the system to pumping stresses by using a mathematical model. The aquifer system consists of three aquifers. The lower aquifer is in fluvial sequences of Quaternary Aromas Sand below interbedded clay layers. The middle aquifer is in upper fluvial and lower eolian sequence of Aromas Sand, and in overlying basal gravels in terrace deposits and alluvium. Weathered soil zones in the Aromas Sand, and clay layers in the terrace deposits and alluvium overlie the middle aquifer. The upper aquifer is actually many discontinuous water bearing zones in the Aromas Sand, terrace deposits, alluvium, and dune sand. The three aquifers are represented in the mathematical model by three model layers separated by two confining layers. Model-generated water budgets for the 11-year simulation period show that storage decreased by 23,000 acre-ft, mostly during the 1976-77 drought. The calibrated model can simulate, with acceptable accuracy, both semiannual and long-term trends of potentiometric heads in parts of the lower and middle layers. (USGS)","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/wri874281","usgsCitation":"Johnson, M.J., Londquist, C., Laudon, J., and Mitten, H., 1988, Geohydrology and mathematical simulation of the Pajaro Valley aquifer system, Santa Cruz and Monterey Counties, California: U.S. Geological Survey Water-Resources Investigations Report 87-4281, 62 p., https://doi.org/10.3133/wri874281.","productDescription":"62 p.","costCenters":[],"links":[{"id":54237,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1987/4281/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":122871,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1987/4281/report-thumb.jpg"},{"id":415539,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_46925.htm","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"California","county":"Monterey County, Santa Cruz County","otherGeospatial":"Pajaro Valley aquifer system","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -121.9167,\n 36.9833\n ],\n [\n -121.9167,\n 36.7917\n ],\n [\n -121.5,\n 36.7917\n ],\n [\n -121.5,\n 36.9833\n ],\n [\n -121.9167,\n 36.9833\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b1be4b07f02db6a8ca6","contributors":{"authors":[{"text":"Johnson, M. J.","contributorId":52988,"corporation":false,"usgs":true,"family":"Johnson","given":"M.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":194026,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Londquist, C.J.","contributorId":86796,"corporation":false,"usgs":true,"family":"Londquist","given":"C.J.","affiliations":[],"preferred":false,"id":194028,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Laudon, Julie","contributorId":68320,"corporation":false,"usgs":true,"family":"Laudon","given":"Julie","email":"","affiliations":[],"preferred":false,"id":194027,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Mitten, H. T.","contributorId":88735,"corporation":false,"usgs":true,"family":"Mitten","given":"H. T.","affiliations":[],"preferred":false,"id":194029,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70014341,"text":"70014341 - 1988 - Retardations in fault creep rates before local moderate earthquakes along the San Andreas fault system, central California","interactions":[],"lastModifiedDate":"2012-03-12T17:19:29","indexId":"70014341","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3209,"text":"Pure and Applied Geophysics PAGEOPH","active":true,"publicationSubtype":{"id":10}},"title":"Retardations in fault creep rates before local moderate earthquakes along the San Andreas fault system, central California","docAbstract":"Records of shallow aseismic slip (fault creep) obtained along parts of the San Andreas and Calaveras faults in central California demonstrate that significant changes in creep rates often have been associated with local moderate earthquakes. An immediate postearthquake increase followed by gradual, long-term decay back to a previous background rate is generally the most obvious earthquake effect on fault creep. This phenomenon, identified as aseismic afterslip, usually is characterized by above-average creep rates for several months to a few years. In several cases, minor step-like movements, called coseismic slip events, have occurred at or near the times of mainshocks. One extreme case of coseismic slip, recorded at Cienega Winery on the San Andreas fault 17.5 km southeast of San Juan Bautista, consisted of 11 mm of sudden displacement coincident with earthquakes of ML=5.3 and ML=5.2 that occurred 2.5 minutes apart on 9 April 1961. At least one of these shocks originated on the main fault beneath the winery. Creep activity subsequently stopped at the winery for 19 months, then gradually returned to a nearly steady rate slightly below the previous long-term average. The phenomena mentioned above can be explained in terms of simple models consisting of relatively weak material along shallow reaches of the fault responding to changes in load imposed by sudden slip within the underlying seismogenic zone. In addition to coseismic slip and afterslip phenomena, however, pre-earthquake retardations in creep rates also have been observed. Onsets of significant, persistent decreases in creep rates have occurred at several sites 12 months or more before the times of moderate earthquakes. A 44-month retardation before the 1979 ML=5.9 Coyote Lake earthquake on the Calaveras fault was recorded at the Shore Road creepmeter site 10 km northwest of Hollister. Creep retardation on the San Andreas fault near San Juan Bautista has been evident in records from one creepmeter site for the past 5 years. Retardations with durations of 21 and 19 months also occurred at Shore Road before the 1974 and 1984 earthquakes of ML=5.2 and ML=6.2, respectively. Although creep retardation remains poorly understood, several possible explanations have been discussed previously. (1) Certain onsets of apparent creep retardation may be explained as abrupt terminations of afterslip generated from previous moderate-mainshock sequences. (2) Retardations may be related to significant decreases in the rate of seismic and/or aseismic slip occurring within or beneath the underlying seismogenic zone. Such decreases may be caused by changes in local conditions related to growth of asperities, strain hardening, or dilatancy, or perhaps by passage of stress-waves or other fluctuations in driving stresses. (3) Finally, creep rates may be lowered (or increased) by stresses imposed on the fault by seismic or aseismic slip on neighboring faults. In addition to causing creep-rate increases or retardations, such fault interactions occasionally may trigger earthquakes. Regardless of the actual mechanisms involved and the current lack of understanding of creep retardation, it appears that shallow fault creep is sensitive to local and regional effects that promote or accompany intermediate-term preparation stages leading to moderate earthquakes. A strategy for more complete monitoring of fault creep, wherever it is known to occur, therefore should be assigned a higher priority in our continuing efforts to test various hypotheses concerning the mechanical relations between seismic and aseismic slip. ?? 1988 Birkha??user Verlag.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Pure and Applied Geophysics PAGEOPH","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisherLocation":"Birkha??user-Verlag","doi":"10.1007/BF00879008","issn":"00334553","usgsCitation":"Burford, R.O., 1988, Retardations in fault creep rates before local moderate earthquakes along the San Andreas fault system, central California: Pure and Applied Geophysics PAGEOPH, v. 126, no. 2-4, p. 499-529, https://doi.org/10.1007/BF00879008.","startPage":"499","endPage":"529","numberOfPages":"31","costCenters":[],"links":[{"id":205660,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF00879008"},{"id":225829,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"126","issue":"2-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505aac03e4b0c8380cd86ae5","contributors":{"authors":[{"text":"Burford, Robert O.","contributorId":52560,"corporation":false,"usgs":true,"family":"Burford","given":"Robert","middleInitial":"O.","affiliations":[],"preferred":false,"id":368160,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70013241,"text":"70013241 - 1988 - Molecular composition and mobility of torbanite precursors: Implications for the structure of coal","interactions":[],"lastModifiedDate":"2023-12-16T00:57:07.285115","indexId":"70013241","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1506,"text":"Energy & Fuels","active":true,"publicationSubtype":{"id":10}},"title":"Molecular composition and mobility of torbanite precursors: Implications for the structure of coal","docAbstract":"Coorongite, a torbanite precursor found in South Australia, and algal residues derived from Botryococcus braunii and other algae have been examined by solid-state 13C NMR techniques. The majority of carbon in these materials is present as (CH2)n. However, variable-temperature studies show that a considerable proportion of the alkyl chains have unusual dipolar-dephasing behavior and are more mobile than in rigid solids. It is suggested that these mobile structures contribute to the so-called \"guest phases\" in coal. The data are also consistent with a vascular and algal model of coal. ?? 1988 American Chemical Society.","language":"English","publisher":"American Chemical Society","doi":"10.1021/ef00011a012","issn":"08870624","usgsCitation":"Wilson, M.A., Batts, B., and Hatcher, P.G., 1988, Molecular composition and mobility of torbanite precursors: Implications for the structure of coal: Energy & Fuels, v. 2, no. 5, p. 668-672, https://doi.org/10.1021/ef00011a012.","productDescription":"5 p.","startPage":"668","endPage":"672","numberOfPages":"5","costCenters":[],"links":[{"id":220298,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"2","issue":"5","noUsgsAuthors":false,"publicationDate":"2002-05-01","publicationStatus":"PW","scienceBaseUri":"505a5cfee4b0c8380cd700af","contributors":{"authors":[{"text":"Wilson, M. A.","contributorId":107649,"corporation":false,"usgs":false,"family":"Wilson","given":"M.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":365614,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Batts, B.D.","contributorId":15757,"corporation":false,"usgs":true,"family":"Batts","given":"B.D.","email":"","affiliations":[],"preferred":false,"id":365612,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hatcher, Patrick G.","contributorId":93625,"corporation":false,"usgs":true,"family":"Hatcher","given":"Patrick","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":365613,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70013689,"text":"70013689 - 1988 - Use of the truncated shifted Pareto distribution in assessing size distribution of oil and gas fields","interactions":[],"lastModifiedDate":"2012-03-12T17:18:38","indexId":"70013689","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2700,"text":"Mathematical Geology","active":true,"publicationSubtype":{"id":10}},"title":"Use of the truncated shifted Pareto distribution in assessing size distribution of oil and gas fields","docAbstract":"The truncated shifted Pareto (TSP) distribution, a variant of the two-parameter Pareto distribution, in which one parameter is added to shift the distribution right and left and the right-hand side is truncated, is used to model size distributions of oil and gas fields for resource assessment. Assumptions about limits to the left-hand and right-hand side reduce the number of parameters to two. The TSP distribution has advantages over the more customary lognormal distribution because it has a simple analytic expression, allowing exact computation of several statistics of interest, has a \"J-shape,\" and has more flexibility in the thickness of the right-hand tail. Oil field sizes from the Minnelusa play in the Powder River Basin, Wyoming and Montana, are used as a case study. Probability plotting procedures allow easy visualization of the fit and help the assessment. ?? 1988 International Association for Mathematical Geology.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Mathematical Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisherLocation":"Kluwer Academic Publishers-Plenum Publishers","doi":"10.1007/BF00892970","issn":"08828121","usgsCitation":"Houghton, J., 1988, Use of the truncated shifted Pareto distribution in assessing size distribution of oil and gas fields: Mathematical Geology, v. 20, no. 8, p. 907-937, https://doi.org/10.1007/BF00892970.","startPage":"907","endPage":"937","numberOfPages":"31","costCenters":[],"links":[{"id":205028,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF00892970"},{"id":220327,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"20","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bbfa1e4b08c986b329c8a","contributors":{"authors":[{"text":"Houghton, J.C.","contributorId":72801,"corporation":false,"usgs":true,"family":"Houghton","given":"J.C.","email":"","affiliations":[],"preferred":false,"id":366645,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70013693,"text":"70013693 - 1988 - Crustal contributions to arc magmatism in the Andes of Central Chile","interactions":[],"lastModifiedDate":"2012-03-12T17:18:32","indexId":"70013693","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","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":"Crustal contributions to arc magmatism in the Andes of Central Chile","docAbstract":"Fifteen andesite-dacite stratovolcanoes on the volcanic front of a single segment of the Andean arc show along-arc changes in isotopic and elemental ratios that demonstrate large crustal contributions to magma genesis. All 15 centers lie 90 km above the Benioff zone and 280??20 km from the trench axis. Rate and geometry of subduction and composition and age of subducted sediments and seafloor are nearly constant along the segment. Nonetheless, from S to N along the volcanic front (at 57.5% SiO2) K2O rises from 1.1 to 2.4 wt %, Ba from 300 to 600 ppm, and Ce from 25 to 50 ppm, whereas FeO*/MgO declines from >2.5 to 1.4. Ce/Yb and Hf/Lu triple northward, in part reflecting suppression of HREE enrichment by deep-crustal garnet. Rb, Cs, Th, and U contents all rise markedly from S to N, but Rb/Cs values double northward - opposite to prediction were the regional alkali enrichment controlled by sediment subduction. K/Rb drops steeply and scatters greatly within many (biotite-free) andesitic suites. Wide diversity in Zr/Hf, Zr/Rb, Ba/Ta, and Ba/La within and among neighboring suites (which lack zircon and alkali feldspar) largely reflects local variability of intracrustal (not slab or mantle) contributions. Pb-isotope data define a limited range that straddles the Stacey-Kramers line, is bracketed by values of local basement rocks, in part plots above the field of Nazca plate sediment, and shows no indication of a steep (mantle+sedimentary) Pb mixing trend. 87Sr/86Sr values rise northward from 0.7036 to 0.7057, and 143Nd/144Nd values drop from 0.5129 to 0.5125. A northward climb in basal elevation of volcanic-front edifices from 1350 m to 4500 m elevation coincides with a Bougueranomaly gradient from -95 to -295 mgal, interpreted to indicate thickening of the crust from 30-35 km to 50-60 km. Complementary to the thickening crust, the mantle wedge beneath the front thins northward from about 60 km to 30-40 km (as slab depth is constant). The thick northern crust contains an abundance of Paleozoic and Triassic rocks, whereas the proportion of younger arc-intrusive basement increases southward. Primitive basalts are unknown anywhere along the arc. Base-level isotopic and chemical values for each volcano are established by blending of subcrustal and deep-crustal magmas in zones of melting, assimilation, storage and homogenization (MASH) at the mantle-crust transition. Scavenging of mid-to upper-crustal silicic-alkalic melts and intracrustal AFC (prominent at the largest center) can subsequently modify ascending magmas, but the base-level geochemical signature at each center reflects the depth of its MASH zone and the age, composition, and proportional contribution of the lowermost crust. ?? 1988 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/BF00372365","issn":"00107999","usgsCitation":"Hildreth, W., and Moorbath, S., 1988, Crustal contributions to arc magmatism in the Andes of Central Chile: Contributions to Mineralogy and Petrology, v. 98, no. 4, p. 455-489, https://doi.org/10.1007/BF00372365.","startPage":"455","endPage":"489","numberOfPages":"35","costCenters":[],"links":[{"id":205032,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF00372365"},{"id":220388,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"98","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fcdae4b0c8380cd4e47e","contributors":{"authors":[{"text":"Hildreth, W. 0000-0002-7925-4251","orcid":"https://orcid.org/0000-0002-7925-4251","contributorId":100487,"corporation":false,"usgs":true,"family":"Hildreth","given":"W.","affiliations":[],"preferred":false,"id":366655,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Moorbath, S.","contributorId":49516,"corporation":false,"usgs":true,"family":"Moorbath","given":"S.","email":"","affiliations":[],"preferred":false,"id":366654,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70013694,"text":"70013694 - 1988 - On low-frequency errors of uniformly modulated filtered white-noise models for ground motions","interactions":[],"lastModifiedDate":"2013-03-13T15:23:09","indexId":"70013694","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1434,"text":"Earthquake Engineering and Structural Dynamics","active":true,"publicationSubtype":{"id":10}},"title":"On low-frequency errors of uniformly modulated filtered white-noise models for ground motions","docAbstract":"Low-frequency errors of a commonly used non-stationary stochastic model (uniformly modulated filtered white-noise model) for earthquake ground motions are investigated. It is shown both analytically and by numerical simulation that uniformly modulated filter white-noise-type models systematically overestimate the spectral response for periods longer than the effective duration of the earthquake, because of the built-in low-frequency errors in the model. The errors, which are significant for low-magnitude short-duration earthquakes, can be eliminated by using the filtered shot-noise-type models (i. e. white noise, modulated by the envelope first, and then filtered).","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Earthquake Engineering and Structural Dynamics","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Wiley","doi":"10.1002/eqe.4290160307","issn":"03756297","usgsCitation":"Safak, E., and Boore, D.M., 1988, On low-frequency errors of uniformly modulated filtered white-noise models for ground motions: Earthquake Engineering and Structural Dynamics, v. 16, no. 3, p. 381-388, https://doi.org/10.1002/eqe.4290160307.","startPage":"381","endPage":"388","numberOfPages":"8","costCenters":[],"links":[{"id":220389,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":269244,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1002/eqe.4290160307"}],"volume":"16","issue":"3","noUsgsAuthors":false,"publicationDate":"2006-12-18","publicationStatus":"PW","scienceBaseUri":"505a69e6e4b0c8380cd73f74","contributors":{"authors":[{"text":"Safak, Erdal","contributorId":73984,"corporation":false,"usgs":true,"family":"Safak","given":"Erdal","email":"","affiliations":[],"preferred":false,"id":366657,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Boore, David M. boore@usgs.gov","contributorId":2509,"corporation":false,"usgs":true,"family":"Boore","given":"David","email":"boore@usgs.gov","middleInitial":"M.","affiliations":[{"id":237,"text":"Earthquake Science Center","active":true,"usgs":true}],"preferred":false,"id":366656,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70013698,"text":"70013698 - 1988 - Simulation and video animation of canal flushing created by a tide gate","interactions":[],"lastModifiedDate":"2012-03-12T17:18:30","indexId":"70013698","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Simulation and video animation of canal flushing created by a tide gate","docAbstract":"A tide-gate algorithm was added to a one-dimensional unsteady flow model that was calibrated, verified, and used to determine the locations of as many as five tide gates that would maximize flushing in two canal systems. Results from the flow model were used to run a branched Lagrangian transport model to simulate the flushing of a conservative constituent from the canal systems both with and without tide gates. A tide gate produces a part-time riverine flow through the canal system that improves flushing along the flow path created by the tide gate. Flushing with no tide gates and with a single optimally located tide gate are shown with a video animation.","conferenceTitle":"Hydraulic Engineering: Proceedings of the 1988 National Conference on Hydraulic Engineering","conferenceDate":"8 August 1988 through 12 August 1988","conferenceLocation":"Colorado Springs, CO, USA","language":"English","publisher":"Publ by ASCE","publisherLocation":"New York, NY, United States","isbn":"0872626709; 0872626709","usgsCitation":"Schoellhamer, D., 1988, Simulation and video animation of canal flushing created by a tide gate, Hydraulic Engineering: Proceedings of the 1988 National Conference on Hydraulic Engineering, Colorado Springs, CO, USA, 8 August 1988 through 12 August 1988, p. 788-793.","startPage":"788","endPage":"793","numberOfPages":"6","costCenters":[],"links":[{"id":220447,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8fe8e4b08c986b3191f0","contributors":{"authors":[{"text":"Schoellhamer, David H. 0000-0001-9488-7340 dschoell@usgs.gov","orcid":"https://orcid.org/0000-0001-9488-7340","contributorId":631,"corporation":false,"usgs":true,"family":"Schoellhamer","given":"David H.","email":"dschoell@usgs.gov","affiliations":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":true,"id":366666,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70013704,"text":"70013704 - 1988 - A conceptual framework for assessing cumulative impacts on the hydrology of nontidal wetlands","interactions":[],"lastModifiedDate":"2018-03-13T11:43:25","indexId":"70013704","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1547,"text":"Environmental Management","active":true,"publicationSubtype":{"id":10}},"title":"A conceptual framework for assessing cumulative impacts on the hydrology of nontidal wetlands","docAbstract":"Wetlands occur in geologic and hydrologic settings that enhance the accumulation or retention of water. Regional slope, local relief, and permeability of the land surface are major controls on the formation of wetlands by surface-water sources. However, these landscape features also have significant control over groundwater flow systems, which commonly play a role in the formation of wetlands. Because the hydrologic system is a continuum, any modification of one component will have an effect on contiguous components. Disturbances commonly affecting the hydrologic system as it relates to wetlands include weather modification, alteration of plant communities, storage of surface water, road construction, drainage of surface water and soil water, alteration of groundwater recharge and discharge areas, and pumping of groundwater. Assessments of the cumulative effects of one or more of these disturbances on the hydrologic system as related to wetlands must take into account uncertainty in the measurements and in the assumptions that are made in hydrologic studies. For example, it may be appropriate to assume that regional groundwater flow systems are recharged in uplands and discharged in lowlands. However, a similar assumption commonly does not apply on a local scale, because of the spatial and temporal dynamics of groundwater recharge. Lack of appreciation of such hydrologic factors can lead to misunderstanding of the hydrologic function of wetlands within various parts of the landscape and mismanagement of wetland ecosystems.
","language":"English","publisher":"Springer","doi":"10.1007/BF01867539","issn":"0364152X","usgsCitation":"Winter, T.C., 1988, A conceptual framework for assessing cumulative impacts on the hydrology of nontidal wetlands: Environmental Management, v. 12, no. 5, p. 605-620, https://doi.org/10.1007/BF01867539.","productDescription":"16 p.","startPage":"605","endPage":"620","numberOfPages":"16","costCenters":[{"id":478,"text":"North Dakota Water Science Center","active":true,"usgs":true},{"id":34685,"text":"Dakota Water Science Center","active":true,"usgs":true}],"links":[{"id":220553,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":205045,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF01867539"}],"volume":"12","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e392e4b0c8380cd460db","contributors":{"authors":[{"text":"Winter, Thomas C.","contributorId":84736,"corporation":false,"usgs":true,"family":"Winter","given":"Thomas","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":366675,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70013705,"text":"70013705 - 1988 - Liquid-vapor relations in the critical region of the system NaCl-H2O from 380 to 415°C: A refined determination of the critical point and two-phase boundary of seawater","interactions":[],"lastModifiedDate":"2015-06-02T10:56:25","indexId":"70013705","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","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":"Liquid-vapor relations in the critical region of the system NaCl-H2O from 380 to 415°C: A refined determination of the critical point and two-phase boundary of seawater","docAbstract":"Pressure-temperature-composition (P-T-x) relations for coexisting vapor and liquid phases in the system NaCl-H2O were determined experimentally in the critical region from 380 to 415°C. The results provide much improved control on the P-T-x critical line in this region. The critical point of seawater (3.2 wt% NaCl solution), which is bracketed in the present study, is at 407°C and 298.5 bar. In addition, the P-T two-phase boundary of seawater was re-determined. These results provide increased precision and accuracy for theoretical models of critical phenomena in this important two-component system and of the limiting P- Tconditions of seawater in seafloor geothermal systems.
","language":"English","publisher":"Elsevier","doi":"10.1016/0016-7037(88)90192-5","issn":"00167037","usgsCitation":"Bischoff, J.L., and Rosenbauer, R.J., 1988, Liquid-vapor relations in the critical region of the system NaCl-H2O from 380 to 415°C: A refined determination of the critical point and two-phase boundary of seawater: Geochimica et Cosmochimica Acta, v. 52, no. 8, p. 2121-2126, https://doi.org/10.1016/0016-7037(88)90192-5.","productDescription":"6 p.","startPage":"2121","endPage":"2126","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":220554,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"52","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a4802e4b0c8380cd67b53","contributors":{"authors":[{"text":"Bischoff, James L. jbischoff@usgs.gov","contributorId":1389,"corporation":false,"usgs":true,"family":"Bischoff","given":"James","email":"jbischoff@usgs.gov","middleInitial":"L.","affiliations":[],"preferred":true,"id":366676,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Rosenbauer, Robert J. brosenbauer@usgs.gov","contributorId":204,"corporation":false,"usgs":true,"family":"Rosenbauer","given":"Robert","email":"brosenbauer@usgs.gov","middleInitial":"J.","affiliations":[{"id":520,"text":"Pacific Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":true,"id":366677,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70013706,"text":"70013706 - 1988 - Pyrolysis g.c.-m.s. of a series of degraded woods and coalified logs that increase in rank from peat to subbituminous coal","interactions":[],"lastModifiedDate":"2023-09-29T14:08:37.902408","indexId":"70013706","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1709,"text":"Fuel","active":true,"publicationSubtype":{"id":10}},"title":"Pyrolysis g.c.-m.s. of a series of degraded woods and coalified logs that increase in rank from peat to subbituminous coal","docAbstract":"Xylem tissue from degraded wood and coalified logs or stems was examined by pyrolysis g.c.-m.s. to improve understanding of the coalification process. The pyrolysis data, when combined with solid-state 13C n.m.r. data for the same samples, show several stages of evolution during coalification. The first stage, microbial degradation in peat, involves the selective degradation of cellulosic components and preservation of lignin-like components. As coalification increases, the lignin structural units undergo a series of defunctionalization reactions. The first of these involve loss of methoxyl groups, with replacement by phenolic hydroxyls such that catechol-like structures are produced. As the xylem tissue is converted to subbituminous coal, the persistence of phenols and methylated phenols in pyrolysis g.c.-m.s. data of subbituminous coal suggests that the catechol-like structures are being converted to phenol-like structures. The ability to discern detailed changes in the chemical structural composition of a genetically and histologically related series of samples provides an ideal method for developing models of coal structure, especially that of low-rank coal.
","language":"English","publisher":"Elsevier","doi":"10.1016/0016-2361(88)90372-9","issn":"00162361","usgsCitation":"Hatcher, P.G., Lerch, H.E., Kotra, R., and Verheyen, T., 1988, Pyrolysis g.c.-m.s. of a series of degraded woods and coalified logs that increase in rank from peat to subbituminous coal: Fuel, v. 67, no. 8, p. 1069-1075, https://doi.org/10.1016/0016-2361(88)90372-9.","productDescription":"7 p.","startPage":"1069","endPage":"1075","costCenters":[],"links":[{"id":220604,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"67","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a905ee4b0c8380cd7fcc7","contributors":{"authors":[{"text":"Hatcher, Patrick G.","contributorId":93625,"corporation":false,"usgs":true,"family":"Hatcher","given":"Patrick","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":366678,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lerch, H. E. III","contributorId":94788,"corporation":false,"usgs":true,"family":"Lerch","given":"H.","suffix":"III","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":366679,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kotra, R. K.","contributorId":100880,"corporation":false,"usgs":true,"family":"Kotra","given":"R. K.","affiliations":[],"preferred":false,"id":366681,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Verheyen, T.V.","contributorId":95614,"corporation":false,"usgs":true,"family":"Verheyen","given":"T.V.","email":"","affiliations":[],"preferred":false,"id":366680,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70013711,"text":"70013711 - 1988 - A late Wisconsinan marine incursion into Cape Cod Bay, Massachusetts","interactions":[],"lastModifiedDate":"2013-01-26T07:07:56","indexId":"70013711","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","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":"A late Wisconsinan marine incursion into Cape Cod Bay, Massachusetts","docAbstract":"Reinterpretation of seismic-reflection data from Cape Cod Bay has produced a revised late Wisconsinan history. Acoustically laminated deposits, originally inferred to be glaciolacustrine, are shown to be glaciomarine by tracing them to glaciomarine mud in Stellwagen Basin, north of Cape Cod Bay. A late Wisconsinan marine deposit of nonglacial origin overlies the glaciomarine deposits in Cape Cod Bay. Both deposits indicate that the crust was isostatically depressed below the late Wisconsinan eustatic sea level and that deglaciation and marine submergence occurred simultaneously. Valleys cut into the marine deposits, both glacial and nonglacial, indicate that a low sea-level stand, the result of isostatic rebound, occurred shortly after the marine incursion. A transgressive uncomformity and marine deposits, both mostly of Holocene age, overlie the late Wisconsinan deposits. The marine incursion, regression, and Holocene transgression represent the northward passage of an isostatically induced peripheral bulge following deglaciation. In turn, the bulge, a response to crustal loading and unloading, indicates thick glacier ice in the terminal zone and lends support to arguments for a maximum Laurentide ice model. Evidence for a late Wisconsinan marine incursion, regression, and the passage of a peripheral bulge should be sought in the other bays and sounds of the New England terminal zone. ?? 1988.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Quaternary Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier","publisherLocation":"Amsterdam, Netherlands","doi":"10.1016/0033-5894(88)90001-4","issn":"00335894","usgsCitation":"Oldale, R.N., 1988, A late Wisconsinan marine incursion into Cape Cod Bay, Massachusetts: Quaternary Research, v. 30, no. 3, p. 237-250, https://doi.org/10.1016/0033-5894(88)90001-4.","startPage":"237","endPage":"250","numberOfPages":"14","costCenters":[],"links":[{"id":220663,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":266523,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0033-5894(88)90001-4"}],"volume":"30","issue":"3","noUsgsAuthors":false,"publicationDate":"2017-01-20","publicationStatus":"PW","scienceBaseUri":"5059e434e4b0c8380cd464ce","contributors":{"authors":[{"text":"Oldale, R. N.","contributorId":92680,"corporation":false,"usgs":true,"family":"Oldale","given":"R.","email":"","middleInitial":"N.","affiliations":[],"preferred":false,"id":366690,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70013724,"text":"70013724 - 1988 - Distribution of selenium in soils of agricultural fields, western San Joaquin Valley, California","interactions":[{"subject":{"id":13696,"text":"ofr87467 - 1987 - Distribution of selenium in soils of agricultural fields, western San Joaquin Valley, California","indexId":"ofr87467","publicationYear":"1987","noYear":false,"title":"Distribution of selenium in soils of agricultural fields, western San Joaquin Valley, California"},"predicate":"SUPERSEDED_BY","object":{"id":70013724,"text":"70013724 - 1988 - Distribution of selenium in soils of agricultural fields, western San Joaquin Valley, California","indexId":"70013724","publicationYear":"1988","noYear":false,"title":"Distribution of selenium in soils of agricultural fields, western San Joaquin Valley, California"},"id":1}],"lastModifiedDate":"2018-09-18T09:44:10","indexId":"70013724","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3420,"text":"Soil Science Society of America Journal","active":true,"publicationSubtype":{"id":10}},"title":"Distribution of selenium in soils of agricultural fields, western San Joaquin Valley, California","docAbstract":"Soils from three agricultural fields in the Panoche Creek alluvial fan area in the western San Joaquin Valley, California, were analyzed for soluble, adsorbed, and total concentrations of selenium (Se) to assess the distribution and forms of Se in relation to the leaching of Se from soils. This assessment is needed to evaluate the importance of soil Se in affecting ground water concentrations. Soil samples were collected from three fields with drainage systems of different ages (6, 15, 1.5 yr) and different Se concentrations in drain water (58, 430, 3700 µg L−1, respectively). Concentrations of soluble Se and salinity were highest in soils from the field drained for 1.5 yr and lowest in the field drained for 6 yr. Of the total concentration of soil Se from all three fields, the proportion of adsorbed and soluble Se ranged from 1 to 11% and <1 to 63%, respectively. Most of the soluble Se was present as selenate and most of the adsorbed Se was found to be selenite. Consistent with a model of evaporative concentration of Se and salinity in soils and shallow ground water in this area, most of the variance in soluble Se is explained by salinity (r2 > 0.68) in saturation extracts of soils sampled from below the water table. In contrast, most soluble salts and Se apparently have been leached from the unsaturated soils in the fields drained for 6 and 15 yr. For the leached soils, dissolution and precipitation of evaporite minerals containing Se may no longer control concentrations of soluble Se.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Soil Science Society of America Journal","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Soil Science Society of America","doi":"10.2136/sssaj1988.03615995005200050011x","issn":"03615995","usgsCitation":"Fujii, R., Deverel, S.J., and Hatfield, D.B., 1988, Distribution of selenium in soils of agricultural fields, western San Joaquin Valley, California: Soil Science Society of America Journal, v. 52, no. 5, p. 1274-1283, https://doi.org/10.2136/sssaj1988.03615995005200050011x.","productDescription":"10 p.","startPage":"1274","endPage":"1283","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":220053,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":276963,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.2136/sssaj1988.03615995005200050011x"}],"country":"United States","state":"California","otherGeospatial":"San Joaquin Valley","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -121.8438,38.1663 ], [ -121.8438,35.0589 ], [ -118.6734,35.0589 ], [ -118.6734,38.1663 ], [ -121.8438,38.1663 ] ] ] } } ] }","volume":"52","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0300e4b0c8380cd502c6","contributors":{"authors":[{"text":"Fujii, Roger rfujii@usgs.gov","contributorId":553,"corporation":false,"usgs":true,"family":"Fujii","given":"Roger","email":"rfujii@usgs.gov","affiliations":[{"id":595,"text":"U.S. Geological Survey","active":false,"usgs":true}],"preferred":false,"id":366725,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Deverel, S. J.","contributorId":65478,"corporation":false,"usgs":true,"family":"Deverel","given":"S.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":366727,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hatfield, D. B.","contributorId":33329,"corporation":false,"usgs":true,"family":"Hatfield","given":"D.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":366726,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70013181,"text":"70013181 - 1988 - Seismic imaging of extended crust with emphasis on the western United States","interactions":[],"lastModifiedDate":"2023-12-28T00:54:05.431735","indexId":"70013181","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","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":"Seismic imaging of extended crust with emphasis on the western United States","docAbstract":"Understanding of the crust has improved dramatically following the application of seismic reflection and refraction techniques to studies of the deep crust. This is particularly true in areas where the last tectonic event was extensional, such as the Basin and Range province of the western United States and much of western Europe. In these regions, a characteristic reflective pattern has emerged, whereby the lower crust is highly reflective and the upper crust and upper mantle are either poorly reflective or strikingly nonreflective. In the metamorphic-core-complex belt in the western United States, where extension can be as much as an order of magnitude greater than in the more classic continental rift zones, the lower crustal reflectivity thickens and rises, yielding a picture of a crust that is reflective throughout. Synthetic seismic studies have documented that the reflectivity in these regions can be modeled by numerous laminae tens of meters thick and hundreds of meters across, characterized by inter-layered high and low velocities. Two geologic factors are interpreted as contributing to this layered character: ductile strain, responding to stress in the thermally weakened middle and lower crust, and intrusive layering, corresponding to injection of subhorizontal sheets of mantle-derived magmas. These two processes yield a variety of geologic structures, including transposed compositional layering, mylonitic ductile shear zones, and intrusive mafic sheets, all of which occur at the proper scales to cause the prominent reflectivity observed. If metamorphic core complexes are representative of extended continental crust world-wide, then these results suggest that magmatism and ductile flow have also contributed to the evolution of the middle and lower crust in many other areas around the world.
","language":"English","publisher":"Geological Society of America","doi":"10.1130/0016-7606(1988)100<1361:SIOECW>2.3.CO;2","usgsCitation":"McCarthy, J., and Thompson, G.A., 1988, Seismic imaging of extended crust with emphasis on the western United States: Geological Society of America Bulletin, v. 100, no. 9, p. 1361-1374, https://doi.org/10.1130/0016-7606(1988)100<1361:SIOECW>2.3.CO;2.","productDescription":"14 p.","startPage":"1361","endPage":"1374","numberOfPages":"14","costCenters":[],"links":[{"id":220413,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"100","issue":"9","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8b25e4b08c986b31761c","contributors":{"authors":[{"text":"McCarthy, J.","contributorId":50290,"corporation":false,"usgs":true,"family":"McCarthy","given":"J.","affiliations":[],"preferred":false,"id":365485,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Thompson, G. A.","contributorId":90332,"corporation":false,"usgs":true,"family":"Thompson","given":"G.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":365486,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70013725,"text":"70013725 - 1988 - Groundwater flow and transport modeling","interactions":[],"lastModifiedDate":"2025-04-23T16:45:10.120868","indexId":"70013725","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","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":"Groundwater flow and transport modeling","docAbstract":"Deterministic, distributed-parameter, numerical simulation models for analyzing groundwater flow and transport problems have come to be used almost routinely during the past decade. A review of the theoretical basis and practical use of groundwater flow and solute transport models is used to illustrate the state-of-the-art. Because of errors and uncertainty in defining model parameters, models must be calibrated to obtain a best estimate of the parameters. For flow modeling, data generally are sufficient to allow calibration. For solute-transport modeling, lack of data not only limits calibration, but also causes uncertainty in process description. Where data are available, model reliability should be assessed on the basis of sensitivity tests and measures of goodness-of-fit. Some of these concepts are demonstrated by using two case histories.
The variance in particle position, a measure of dispersion, is reviewed in the context of certain models of flow in random porous media. Asymptotic results for a highly stratified medium and an isotropic medium are particularly highlighted. Results of the natural gradient tracer test at the Borden site are reviewed in light of these models. This review suggests that the moments obtained for the conservative tracers at the Borden site could as well be explained by a model that more explicitly represents the three-dimensional nature of the flow field.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/WR024i012p02099","usgsCitation":"Naff, R., Jim Yeh, T., and Kemblowski, M., 1988, A note on the recent natural gradient tracer test at the Borden Site: Water Resources Research, v. 24, no. 12, p. 2099-2103, https://doi.org/10.1029/WR024i012p02099.","startPage":"2099","endPage":"2103","numberOfPages":"5","costCenters":[],"links":[{"id":220193,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","otherGeospatial":"Borden Site","volume":"24","issue":"12","noUsgsAuthors":false,"publicationDate":"2010-07-09","publicationStatus":"PW","scienceBaseUri":"5059e4c4e4b0c8380cd468f8","contributors":{"authors":[{"text":"Naff, R.L.","contributorId":86349,"corporation":false,"usgs":true,"family":"Naff","given":"R.L.","affiliations":[],"preferred":false,"id":365887,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Jim Yeh, T.-C.","contributorId":95196,"corporation":false,"usgs":true,"family":"Jim Yeh","given":"T.-C.","email":"","affiliations":[],"preferred":false,"id":365888,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kemblowski, M.W.","contributorId":69706,"corporation":false,"usgs":true,"family":"Kemblowski","given":"M.W.","email":"","affiliations":[],"preferred":false,"id":365886,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70013726,"text":"70013726 - 1988 - Regression estimates for topological‐hydrograph input","interactions":[],"lastModifiedDate":"2024-05-23T14:38:34.704288","indexId":"70013726","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2501,"text":"Journal of Water Resources Planning and Management","active":true,"publicationSubtype":{"id":10}},"title":"Regression estimates for topological‐hydrograph input","docAbstract":"Physiographic, hydrologic, and rainfall data from 18 small drainage basins in semiarid, central Wyoming were used to calibrate topological, unit‐hydrograph models for celerity, the average rate of travel of a flood wave through the basin. The data set consisted of basin characteristics and hydrologic data for the 18 basins and rainfall data for 68 storms. Calibrated values of celerity and peak discharges subsequently were regressed as a function of the basin characteristics and excess rainfall volume. Predicted values obtained in this way can be used as input for estimating hydrographs in ungaged basins. The regression models included ordinary least‐squares and seemingly unrelated regression. This latter regression model jointly estimated the celerity and peak discharge. The correlation between residuals of the celerity and peak‐discharge regressions was sufficiently large to de‐, crease the variances of estimated univariate‐model parameters.
","language":"English","publisher":"ASCE","doi":"10.1061/(ASCE)0733-9496(1988)114:4(446)","issn":"07339496","usgsCitation":"Karlinger, M.R., Guertin, D.P., and Troutman, B., 1988, Regression estimates for topological‐hydrograph input: Journal of Water Resources Planning and Management, v. 114, no. 4, p. 446-456, https://doi.org/10.1061/(ASCE)0733-9496(1988)114:4(446).","productDescription":"11 p.","startPage":"446","endPage":"456","numberOfPages":"11","costCenters":[],"links":[{"id":220111,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"114","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a9340e4b0c8380cd80ce2","contributors":{"authors":[{"text":"Karlinger, Michael R.","contributorId":10777,"corporation":false,"usgs":true,"family":"Karlinger","given":"Michael","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":366730,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Guertin, D. Phillip","contributorId":46062,"corporation":false,"usgs":false,"family":"Guertin","given":"D.","email":"","middleInitial":"Phillip","affiliations":[{"id":12625,"text":"School of Natural Resources and the Environment, University of Arizona, Tucson, AZ, 85721, USA","active":true,"usgs":false}],"preferred":false,"id":366732,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Troutman, Brent M.","contributorId":41040,"corporation":false,"usgs":true,"family":"Troutman","given":"Brent M.","affiliations":[],"preferred":false,"id":366731,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70013343,"text":"70013343 - 1988 - The development of the continental margin of eastern North America-conjugate continental margin to West Africa","interactions":[],"lastModifiedDate":"2024-02-27T01:24:09.489309","indexId":"70013343","displayToPublicDate":"1988-01-01T00:00:00","publicationYear":"1988","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2147,"text":"Journal of African Earth Sciences","active":true,"publicationSubtype":{"id":10}},"title":"The development of the continental margin of eastern North America-conjugate continental margin to West Africa","docAbstract":"The continental margin of eastern North America was initiated when West Africa and North America were rifted apart in Triassic-Early Jurassic time. Cooling of the crust and its thinning by rifting and extension caused subsidence. Variation in amounts of subsidence led to formation of five basins. These are listed from south to north. (1) The Blake Plateau Basin, the southernmost, is the widest basin and the one in which the rift-stage basement took longest to form. Carbonate platform deposition was active and persisted until the end of Early Cretaceous. In Late Cretaceous, deposition slowed while subsidence persisted, so a deep water platform was formed. Since the Paleocene the region has undergone erosion. (2) The Carolina Trough is narrow and has relatively thin basement, on the basis of gravity modeling. The two basins with thin basement, the Carolina Trough and Scotian Basin, also show many salt diapirs indicating considerable deposition of salt during their early evolution. In the Carolina Trough, subsidence of a large block of strata above the flowing salt has resulted in a major, active normal fault on the landward side of the basin. (3) The Baltimore Canyon Trough has an extremely thick sedimentary section; synrift and postrift sediments exceed 18 km in thickness. A Jurassic reef is well developed on the basin's seaward side, but post-Jurassic deposition was mainly non-carbonate. In general the conversion from carbonate to terrigenous deposition, characteristics of North American Basins, occurred progressively earlier toward the north. (4) The Georges Bank Basin has a complicated deep structure of sub-basins filled with thick synrift deposits. This may have resulted from some shearing that occurred at this offset of the continental margin. Postrift sediments apparently are thin compared to other basins—only about 8 km. (5) The Scotian Basin, off Canada, contains Jurassic carbonate rocks, sandstone, shale and coal covered by deltaic deposits and Upper Cretaceous deeper water chalk and shale.
Version IV of plumbotectonics expands and refines the original model of Doe and Zartman (1979) and Zartman and Doe (1981) for explaining Pb (Sr, and Nd) isotopic systematics among major terrestrial reservoirs. A case for bi-directional transport among reservoirs is based on the observed isotopic compositions for different tectonic settings, and finds a rationale in the kinetics of plate tectonics. Chemical fractionation and radioactive decay create isotopic differences during periods of isolation of one reservoir from another, whereas dynamic processes allowing mixing between reservoirs tend to reduce these differences. Observed isotopic characteristics reflect a balance between these opposing tendencies and provide constraints on the extent and timing of fractionation and mixing processes.
Plumbotectonics does not require interaction with a lower mantle or core reservoir over most of the Earth's lifetime, and, in fact, achieves a material balance consistent with no such exchange of material.
Important evidence of the amount and timing of crustal recycling, and of the residence times of mantle heterogeneities lies in the coupled
A semianalytical particle tracking method was developed for use with velocities generated from block centered finite-difference ground-water flow models. The method is based on the assumption that each directional velocity component varies linearly within a grid cell in its own coordinate directions. This assumption allows an analytical expression to be obtained describing the flow path within an individual grid cell. Given the initial position of a particle anywhere in a cell, the coordinates of any other point along its path line within the cell, and the time of travel between them, can be computed directly. For steady-state systems, the exit point for a particle entering a cell at any arbitrary location can be computed in a single step. By following the particle as it moves from cell to cell, this method can be used to trace the path of a particle through any multidimensional flow field generated from a block-centered finite-difference flow model.