No abstract available.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Proceedings of the Seminar on two-dimensional flow modeling","largerWorkSubtype":{"id":12,"text":"Conference publication"},"language":"English","publisher":"U.S. Army Corps of Engineers","usgsCitation":"Walters, R.A., 1981, Experiences with the application of the finite element method to the solution of the shallow water equations, in Proceedings of the Seminar on two-dimensional flow modeling.","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":325751,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5799db4de4b0589fa1c7e88a","contributors":{"authors":[{"text":"Walters, R. A.","contributorId":34174,"corporation":false,"usgs":true,"family":"Walters","given":"R.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":643755,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70011952,"text":"70011952 - 1981 - Interpretation of changes in water level accompanying fault creep and implications for earthquake prediction","interactions":[],"lastModifiedDate":"2024-07-16T15:54:28.337138","indexId":"70011952","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":6453,"text":"Journal of Geophysical Research Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"Interpretation of changes in water level accompanying fault creep and implications for earthquake prediction","docAbstract":"Quantitative calculations for the effect of a fault creep event on observations of changes in water level in wells provide an approach to the tectonic interpretation of these phenomena. For the pore pressure field associated with an idealized creep event having an exponential displacement versus time curve, an analytic expression has been obtained in terms of exponential-integral functions. The pore pressure versus time curves for observation points near the fault are pulselike; a sharp pressure increase (or decrease, depending on the direction of propagation) is followed by more gradual decay to the normal level after the creep event. The time function of the water level change may be obtained by applying the filter—derived by A. G. Johnson and others to determine the influence of atmospheric pressure on water level—to the analytic pore pressure versus time curves. The resulting water level curves show a fairly rapid increase (or decrease) and then a very gradual return to normal. The results of this analytic model do not reproduce the steplike changes in water level observed by Johnson and others. If the procedure used to obtain the water level from the pore pressure is correct, these results suggest that steplike changes in water level are not produced by smoothly propagating creep events but by creep events that propagate discontinously, by changes in the bulk properties of the region around the well, or by some other mechanism. In addition, simplistic calculations show that significant pressure field variations and water level changes near the surface may be expected to accompany a propagating creep event on a buried fault. Water level changes of as much as several meters may be expected at the surface for a creep event having a dislocation amplitude of l m on a semi-infinite dislocation surface extending downward from a depth of 10 km and propagating horizontally at a rate of 10 km/day. The maximum near-surface effect should be observed at a horizontal distance from the fault about equal to the depth of the top of the dislocation surface. These results are consistent with the observations made in China of large water level changes preceding large earthquakes, if some sort of aseismic creep event at depth precedes these earthquakes.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB086iB10p09259","issn":"01480227","usgsCitation":"Wesson, R.L., 1981, Interpretation of changes in water level accompanying fault creep and implications for earthquake prediction: Journal of Geophysical Research Solid Earth, v. 86, no. B10, p. 9259-9267, https://doi.org/10.1029/JB086iB10p09259.","productDescription":"9 p.","startPage":"9259","endPage":"9267","numberOfPages":"9","costCenters":[],"links":[{"id":221266,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"86","issue":"B10","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"505a3d6ae4b0c8380cd6355f","contributors":{"authors":[{"text":"Wesson, R. L.","contributorId":51752,"corporation":false,"usgs":true,"family":"Wesson","given":"R.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":362379,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70012081,"text":"70012081 - 1981 - Concentration of some platinum-group metals in coal","interactions":[],"lastModifiedDate":"2024-02-24T01:41:31.292194","indexId":"70012081","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2033,"text":"International Journal of Coal Geology","active":true,"publicationSubtype":{"id":10}},"title":"Concentration of some platinum-group metals in coal","docAbstract":"New data on some platinum group metals in coal indicate that the concentration of Pt is generally less than about 5 ppb, that of Pd is generally less than 1 ppb, and that of Rh is generally less than 0.5 ppb. No conclusive evidence was obtained concerning the mode of occurrence of these elements in coal.
A random model of fault motion in an earthquake is formulated by assuming that the slip velocity is a random function of position and time truncated at zero, so that it does not have negative values. This random function is chosen to be self-affine; that is, on change of length scale, the function is multiplied by a scale factor but is otherwise unchanged statistically. A snapshot of slip velocity at a given time resembles a cluster of islands with rough topography; the final slip function is a smoother island or cluster of islands. In the Fourier transform domain, shear traction on the fault equals the slip velocity times an impedance function. The fact that this impedance function has a pole at zero frequency implies that traction and slip velocity cannot have the same spectral dependence in space and time. To describe stress fluctuations of the order of 100 bars when smoothed over a length of kilometers and of the order of kilobars at the grain size, shear traction must have a one-dimensional power spectrum is space proportional to the reciprocal wave number. Then the one-dimensional power spectrum for the slip velocity is proportional to the reciprocal wave number squared and for slip to its cube. If slip velocity has the same power law spectrum in time as in space, then the spectrum of ground acceleration will be flat (white noise) both on the fault and in the far field.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB086iB11p10821","issn":"01480227","usgsCitation":"Andrews, D., 1981, A stochastic fault model. 2. Time-dependent case: Journal of Geophysical Research Solid Earth, v. 86, no. B11, p. 10821-10834, https://doi.org/10.1029/JB086iB11p10821.","productDescription":"14 p.","startPage":"10821","endPage":"10834","numberOfPages":"14","costCenters":[],"links":[{"id":221313,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"86","issue":"B11","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"5059e5b2e4b0c8380cd46f13","contributors":{"authors":[{"text":"Andrews, D.J.","contributorId":7416,"corporation":false,"usgs":true,"family":"Andrews","given":"D.J.","email":"","affiliations":[],"preferred":false,"id":361896,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70012018,"text":"70012018 - 1981 - Sm-Nd systematics of a tonalitic augen gneiss and its constituent minerals from northern Michigan","interactions":[],"lastModifiedDate":"2024-03-18T14:00:26.881376","indexId":"70012018","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","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":"Sm-Nd systematics of a tonalitic augen gneiss and its constituent minerals from northern Michigan","docAbstract":"The Sm-Nd isotopic system of a tonalitic augen gneiss and its constituent minerals from northern Michigan was disturbed during metamorphism. Sm-Nd zircon ages are lower than the wholerock Sm-Nd model age. However, closely associated pairs of minerals (for example, sphene and biotite or apatite and plagioclase) retain their apparent metamorphic ages. The Sm-Nd model age for the tonalitic augen gneiss of 3919 ± 30myr, appears to reflect open system behavior during metamorphism. A mineralogically different gneiss from the same location has a Sm-Nd model age of 3520 ± 70 myr. The two whole rocks differ in their Sm-Nd and Rb-Sr systematics and in their chondrite-normalized rare earth element (REE) patterns. The whole-rock-normalized mineral REE patterns show the contribution of the major and trace minerals to the REE content of the whole rock. The trace minerals contain a significant amount of the total REE.
","language":"English","publisher":"Elsevier","doi":"10.1016/0016-7037(81)90148-4","issn":"00167037","usgsCitation":"Futa, K., 1981, Sm-Nd systematics of a tonalitic augen gneiss and its constituent minerals from northern Michigan: Geochimica et Cosmochimica Acta, v. 45, no. 7, p. 1245-1249, https://doi.org/10.1016/0016-7037(81)90148-4.","productDescription":"5 p.","startPage":"1245","endPage":"1249","numberOfPages":"5","costCenters":[],"links":[{"id":222287,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"45","issue":"7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b917ce4b08c986b319925","contributors":{"authors":[{"text":"Futa, K.","contributorId":26435,"corporation":false,"usgs":true,"family":"Futa","given":"K.","affiliations":[],"preferred":false,"id":362531,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70010351,"text":"70010351 - 1981 - Design of exploration and minerals-data-collection programs in developing areas","interactions":[],"lastModifiedDate":"2025-09-12T17:16:27.217638","indexId":"70010351","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3414,"text":"Socio-Economic Planning Sciences","active":true,"publicationSubtype":{"id":10}},"title":"Design of exploration and minerals-data-collection programs in developing areas","docAbstract":"This paper considers the practical problem of applying economic analysis to designing minerals exploration and data collection strategies for developing countries. Formal decision rules for the design of government exploration and minerals-data-collection programs are derived by using a minerals-industry planning model that has been extended to include an exploration function. Rules derived are applicable to centrally planned minerals industries as well as market-oriented minerals sectors. They pertain to the spatial allocation of exploration effort and to the allocation of activities between government and private concerns for market-oriented economies. Programs characterized by uniform expenditures, uniform information coverage across regions, or uniform-density grid drilling progrmas are shown to be inferior to the strategy derived. Moreover, for market-oriented economies, the economically optimal mix in exploration activities between private and government data collection would require that only private firms assess local sites and that government agencies carry out regional surveys.
","language":"English","publisher":"Elsevier","doi":"10.1016/0038-0121(81)90037-9","issn":"00380121","usgsCitation":"Attanasi, E.D., 1981, Design of exploration and minerals-data-collection programs in developing areas: Socio-Economic Planning Sciences, v. 15, no. 6, p. 347-352, https://doi.org/10.1016/0038-0121(81)90037-9.","productDescription":"6 p.","startPage":"347","endPage":"352","numberOfPages":"6","costCenters":[],"links":[{"id":219367,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"15","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ff3fe4b0c8380cd4f0c4","contributors":{"authors":[{"text":"Attanasi, E. D. 0000-0001-6845-7160","orcid":"https://orcid.org/0000-0001-6845-7160","contributorId":107672,"corporation":false,"usgs":true,"family":"Attanasi","given":"E.","middleInitial":"D.","affiliations":[],"preferred":false,"id":358698,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70012015,"text":"70012015 - 1981 - Seismic amplitude anomalies associated with thick First Leo sandstone lenses, eastern Powder River basin, Wyoming","interactions":[],"lastModifiedDate":"2024-04-18T16:37:38.604821","indexId":"70012015","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1808,"text":"Geophysics","active":true,"publicationSubtype":{"id":10}},"title":"Seismic amplitude anomalies associated with thick First Leo sandstone lenses, eastern Powder River basin, Wyoming","docAbstract":"Several new discoveries of oil production in the Leo sandstone, an economic unit in the Pennsylvanian middle member of the Minnelusa formation, eastern Powder River basin, Wyoming-Nebraska-South Dakota, have renewed exploration interest in this area. Vertical seismic profiles (VSP) and model studies suggested that a measurable seismic amplitude anomaly is frequently associated with the thick First Leo sandstone lenses. To test this concept, a surface reflection seismic profile was run between two wells about 12 miles apart. The First Leo was present and productive in one well and thin and barren in the other. The surface profile shows the predicted amplitude anomaly at the well where a thick lens is known to exist. Two other First Leo amplitude anomalies also appear on the surface seismic profile between the two wells, which may indicate the presence of additional lenses.
","language":"English","publisher":"Society of Exploration Geophysicists","doi":"10.1190/1.1441158","issn":"00168033","usgsCitation":"Balch, A.H., Lee, M.W., Miller, J.J., and Ryder, R.T., 1981, Seismic amplitude anomalies associated with thick First Leo sandstone lenses, eastern Powder River basin, Wyoming: Geophysics, v. 46, no. 11, p. 1519-1527, https://doi.org/10.1190/1.1441158.","productDescription":"9 p.","startPage":"1519","endPage":"1527","numberOfPages":"9","costCenters":[],"links":[{"id":222284,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"46","issue":"11","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8aece4b08c986b317475","contributors":{"authors":[{"text":"Balch, A. H.","contributorId":104892,"corporation":false,"usgs":true,"family":"Balch","given":"A.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":362522,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lee, Myung W.","contributorId":84358,"corporation":false,"usgs":true,"family":"Lee","given":"Myung","middleInitial":"W.","affiliations":[],"preferred":false,"id":362520,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Miller, J. J.","contributorId":54588,"corporation":false,"usgs":true,"family":"Miller","given":"J.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":362519,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Ryder, R. T.","contributorId":96673,"corporation":false,"usgs":true,"family":"Ryder","given":"R.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":362521,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70011854,"text":"70011854 - 1981 - Blast dynamics at Mount St Helens on 18 May 1980","interactions":[],"lastModifiedDate":"2012-03-12T17:18:33","indexId":"70011854","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2840,"text":"Nature","active":true,"publicationSubtype":{"id":10}},"title":"Blast dynamics at Mount St Helens on 18 May 1980","docAbstract":"At 8.32 a.m. on 18 May 1980, failure of the upper part of the north slope of Mount St Helens triggered a lateral eruption ('the blast') that devastated the conifer forests in a sector covering ???500 km2 north of the volcano. I present here a steady flow model for the blast dynamics and propose that through much of the devastated area the blast was a supersonic flow of a complex multiphase (solid, liquid, vapour) mixture. The shape of the blast zone; pressure, temperature, velocity (Mach number) and density distributions within the flow; positions of weak and strong internal shocks; and mass flux, energy flux, and total energy are calculated. The shape of blast zone was determined by the initial areal expansion from the reservoir, by internal expansion and compression waves (including shocks), and by the density of the expanding mixture. The pressure within the flow dropped rapidly away from the source of the blast until, at a distance of ???11 km, the flow became underpressured relative to the surrounding atmosphere. Weak shocks within the flow subparallel to the east and west margins coalesced at about this distance into a strong Mach disk shock, across which the flow velocities would have dropped from supersonic to subsonic as the pressure rose back towards ambient. The positions of the shocks may be reflected in differences in the patterns of felled trees. At the limits of the devastated area, the temperature had dropped only 20% from the reservoir temperature because the entrained solids thermally buffered the flow (the dynamic and thermodynamic effects of the admixture of the surrounding atmosphere and the uprooted forest and soils into the flow are not considered). The density of the flow decreased with distance until, at the limits of the blast zone, 20-25 km from the volcano, the density became comparable with that of the surrounding (dirty) atmosphere and the flow became buoyant and ramped up into the atmosphere. According to the model, the mass flux per unit area at the source was 0.6 ?? 104 g s-1 cm-2 and the energy flux per unit area was 2.5 MW cm-2. From the measured total ejected mass, 0.25 ?? 1015 g, the total energy released during the eruption was 1024 erg or 24 megatons. The model, triggering of the eruption and the transition from unsteady to steady flow, and applications to eyewitness observations and atmospheric effects are discussed in ref. 1. ?? 1981 Nature Publishing Group.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Nature","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1038/291568a0","issn":"00280836","usgsCitation":"Kieffer, S.W., 1981, Blast dynamics at Mount St Helens on 18 May 1980: Nature, v. 291, no. 5816, p. 568-570, https://doi.org/10.1038/291568a0.","startPage":"568","endPage":"570","numberOfPages":"3","costCenters":[],"links":[{"id":205060,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1038/291568a0"},{"id":220723,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"291","issue":"5816","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f1e0e4b0c8380cd4ae95","contributors":{"authors":[{"text":"Kieffer, S. W.","contributorId":19186,"corporation":false,"usgs":true,"family":"Kieffer","given":"S.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":362123,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70011850,"text":"70011850 - 1981 - A review of regional mineral resource assessment methods","interactions":[],"lastModifiedDate":"2024-01-12T17:11:09.746558","indexId":"70011850","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1472,"text":"Economic Geology","active":true,"publicationSubtype":{"id":10}},"title":"A review of regional mineral resource assessment methods","docAbstract":"Over 100 papers on regional mineral resource assessment of nonfuels are classified according to method(s) used and form(s) of product in order to help identify possible methods for future assessments. Types of products that have been used include: tons of metal; tons of rock and associated grade; gross value; potential; number of deposits; probability of one or more deposits; tons of rock, grade, and number of deposits by type; potential supply; and net value. Assessment methods considered are: time-rate, crustal abundance, cumulative tonnage versus grade, simple subjective, complex subjective, Bayesian, frequency, trend, geometric probability, multiple regression, discriminant analysis, modified component, multivariate logistic, cluster analysis or pattern recognition, and simulation.Selection of a method to be employed in an assessment should be based on: (1) appropriateness of the product to the problem, (2) limitations in resources, such as information or time available for the assessment, (3) the level of uncertainty and acceptability of biases in the assessment, and (4) the need for verification of results and acceptance of the method.
","language":"English","publisher":"Society of Economic Geologists","doi":"10.2113/gsecongeo.76.5.1006","issn":"03610128","usgsCitation":"Singer, D., and Mosier, D., 1981, A review of regional mineral resource assessment methods: Economic Geology, v. 76, no. 5, p. 1006-1015, https://doi.org/10.2113/gsecongeo.76.5.1006.","productDescription":"10 p.","startPage":"1006","endPage":"1015","numberOfPages":"10","costCenters":[],"links":[{"id":221698,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"76","issue":"5","noUsgsAuthors":false,"publicationDate":"1981-08-01","publicationStatus":"PW","scienceBaseUri":"5059e556e4b0c8380cd46cc9","contributors":{"authors":[{"text":"Singer, D.A.","contributorId":69128,"corporation":false,"usgs":true,"family":"Singer","given":"D.A.","email":"","affiliations":[],"preferred":false,"id":362113,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Mosier, D.L.","contributorId":21965,"corporation":false,"usgs":true,"family":"Mosier","given":"D.L.","email":"","affiliations":[],"preferred":false,"id":362112,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70011856,"text":"70011856 - 1981 - Northwest margin of California continental borderland: Marine geology and tectonic evolution","interactions":[],"lastModifiedDate":"2023-01-12T11:53:35.159296","indexId":"70011856","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":701,"text":"American Association of Petroleum Geologists Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"Northwest margin of California continental borderland: Marine geology and tectonic evolution","docAbstract":"The northwest margin of the California continental borderland consists mainly of two northwest-trending pre-Neogene lithologic belts blanketed by Miocene and younger strata. These belts, which are lithologically and structurally correlated with the Franciscan Complex and Great Valley sequence of northern California, are interpreted to represent facies corresponding to the subduction complex and forearc-basin deposits of a late Mesozoic and Paleogene continental-margin arc-trench system. The outer belt, which forms the acoustic basement underlying the continental slope and Patton Ridge, is characterized by: (1) moderately high compressional velocities (5.1 to 6.2 km/sec), (2) discordant and discontinuous seismic reflectors, and (3) nonfossiliferous and diverse rock types t at range in metamorphic grade from zeolite-bearing arkosic sandstone to blueschist. Landward, the inner Great Valley sequence belt underlies Santa Rosa-Cortes Ridge and Santa Cruz and San Nicolas Basins; in contrast to the outer belt, this belt is characterized by: (1) intermediate compressional velocities (4.5 to 4.6 km/sec), (2) concordant and relatively continuous reflectors, and (3) a thick turbidite sequence of relatively undeformed and unmetamorphosed fossiliferous Cretaceous and Paleogene strata. The inner belt overlies a 6.6-km/sec layer that is probably oceanic crust, a relation consistent with the hypothesis that trapped old oceanic crust underlies the forearc basins along parts of some convergent margins.
Well-developed wrench-fault structures in overlying Miocene strata record a transition from Paleogene subduction to Neogene transform faulting. Related events include widespread andesitic to dacitic volcanism and concurrent uplift and erosion of Miocene and older rocks. The proximity of these Miocene silicic volcanic rocks to the paleotrench (< 20 km) is best explained as resulting from passage of the southward-migrating Rivera ridge-fault-trench triple junction along the margin. On the basis of the age of the adjacent sea floor, passage of this triple junction occurred about 17 m.y. ago, a date that corresponds closely to the inception of volcanism and uplift in the northwest margin of the borderland. A widespread unconformity that separates highly deformed lower and lower middle iocene strata from relatively undeformed younger strata is assumed to mark the subsequent onset of wrench faulting.
The timing of volcanism and uplift, and of the slightly younger wrenching event, closely matches the plate-tectonic model of Atwater and Molnar if the northwest margin of the borderland is restored to an earlier tectonic setting off Baja California, approximately 260 km southeast of its present position.
","language":"English","publisher":"American Association of Petroleum Geologists","doi":"10.1306/2F9197A1-16CE-11D7-8645000102C1865D","usgsCitation":"Crouch, J., 1981, Northwest margin of California continental borderland: Marine geology and tectonic evolution: American Association of Petroleum Geologists Bulletin, v. 65, no. 2, p. 191-218, https://doi.org/10.1306/2F9197A1-16CE-11D7-8645000102C1865D.","productDescription":"28 p.","startPage":"191","endPage":"218","numberOfPages":"28","costCenters":[],"links":[{"id":220725,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -118.19125226917674,\n 33.86449981604767\n ],\n [\n -120.63224634312732,\n 33.86449981604767\n ],\n [\n -120.63224634312732,\n 32.238222576392715\n ],\n [\n -118.19125226917674,\n 32.238222576392715\n ],\n [\n -118.19125226917674,\n 33.86449981604767\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"65","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a684ee4b0c8380cd73726","contributors":{"authors":[{"text":"Crouch, J.K.","contributorId":107694,"corporation":false,"usgs":true,"family":"Crouch","given":"J.K.","email":"","affiliations":[],"preferred":false,"id":362129,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70012047,"text":"70012047 - 1981 - Geochemical evidence for modern sediment accumulation on the continental shelf off southern New England","interactions":[],"lastModifiedDate":"2017-11-05T10:29:23","indexId":"70012047","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2450,"text":"Journal of Sedimentary Petrology","active":true,"publicationSubtype":{"id":10}},"title":"Geochemical evidence for modern sediment accumulation on the continental shelf off southern New England","docAbstract":"An area of fine-grained sediment approximately 170 km x 74 km in size, located in water depths between 60 m and 150 m, south of Martha's Vineyard, Mass., is a site of modern sediment deposition. The 14C ages systematically increase with sediment depth from about 1,300 years B.P. at the surface to 8,000-10,000 years B.P. at the depth of maximum core penetration. The old age for the surface sediments probably results from a combination of deposition of old carbon and faunal mixing. In the finest sediments, the sedimentation rates were approximately 130 cm/1,000 yrs when deposition began and have decreased to about 25 cm/1,000 yrs. The decreasing sedimentation rate reflects a diminishing source of fine sediments, which presumably came from the Georges Bank and Nantucket Shoals area. Inventories of excess 210Pb in undisturbed cores average 70 dpm/cm2 (disintegrations per minute per square centimeter), more than two times higher than the flux of 210Pb from the atmosphere and from 226Ra decay in the overlying water. This additional influx of 210Pb either must be with new fine-grained sediment material or from solutions that are stripped of their 210Pb by particulates in the bottom nepheloid layer. Stable Pb concentrations in surface sediments are about 28 ppm, as much as two times higher than concentrations at depth. The high accumulation rates, 210Pb inventories, and trace-metal profiles imply that this area is a modern sink for fine-grained sediments and for pollutants associated with particulate matter in the water column. To our knowledge, this is the only site of present-day natural deposition on the Continental Shelf off the eastern United States, exclusive of the Gulf of Maine. Because the net currents on the outer half of this Continental Shelf flow from northeast to southwest, this fine-grained deposit may receive its sediments and possible contaminants from the Nantucket Shoals and Georges Bank regions.
","language":"English","publisher":"SEPM","doi":"10.1306/212F7C70-2B24-11D7-8648000102C1865D","issn":"00224472","usgsCitation":"Bothner, M., Spiker, E., Johnson, P.P., Rendigs, R., and Aruscavage, P.J., 1981, Geochemical evidence for modern sediment accumulation on the continental shelf off southern New England: Journal of Sedimentary Petrology, v. 51, no. 1, p. 281-292, https://doi.org/10.1306/212F7C70-2B24-11D7-8648000102C1865D.","productDescription":"12 p.","startPage":"281","endPage":"292","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":186,"text":"Coastal and Marine Geology Program","active":true,"usgs":true},{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"links":[{"id":222693,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Massachusetts","otherGeospatial":"New England","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -71.78466796874999,\n 39.308800296002914\n ],\n [\n -71.78466796874999,\n 41.03793062246529\n ],\n [\n -68.258056640625,\n 41.03793062246529\n ],\n [\n -68.258056640625,\n 39.308800296002914\n ],\n [\n -71.78466796874999,\n 39.308800296002914\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"51","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a1630e4b0c8380cd550a0","contributors":{"authors":[{"text":"Bothner, Michael H. mbothner@usgs.gov","contributorId":139855,"corporation":false,"usgs":true,"family":"Bothner","given":"Michael H.","email":"mbothner@usgs.gov","affiliations":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":false,"id":362607,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Spiker, E.C.","contributorId":103275,"corporation":false,"usgs":true,"family":"Spiker","given":"E.C.","affiliations":[],"preferred":false,"id":362609,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Johnson, P. P.","contributorId":64807,"corporation":false,"usgs":true,"family":"Johnson","given":"P.","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":362608,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Rendigs, R.R.","contributorId":50506,"corporation":false,"usgs":true,"family":"Rendigs","given":"R.R.","affiliations":[],"preferred":false,"id":362606,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Aruscavage, P. J.","contributorId":41411,"corporation":false,"usgs":true,"family":"Aruscavage","given":"P.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":362605,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70010322,"text":"70010322 - 1981 - Significant results from using earth observation satellites for mineral and energy resource exploration","interactions":[],"lastModifiedDate":"2017-01-18T15:02:50","indexId":"70010322","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":661,"text":"Advances in Space Research","active":true,"publicationSubtype":{"id":10}},"title":"Significant results from using earth observation satellites for mineral and energy resource exploration","docAbstract":"A large number of Earth-observation satellites orbit our world several times each day, providing new information about the land and sea surfaces and the overlying thin layer of atmosphere that makes our planet unique. Meteorological satellites have had the longest history of experimental use and most are now considered operational. The geologic information collected by the Landsat, Polar Orbiting Geophysical Observatory (POGO), Magsat, Heat Capacity Mapping Mission (HCMM) and Seasat land and ocean observation systems is being thoroughly tested, and some of these systems are now approaching operational use.
\nLandsat multispectral images provide views of large areas of the Earth under uniform lighting conditions and can be obtained at a variety of scales and formats. Not only do the Landsat data provide highly useful images showing surficial materials and structures such as folds and faults, but also measurements and computer-derived ratios of the brightness of different rock types, alteration zones, and mineral associations. These data have led to the finding of a variety of new ore deposits. In addition, the combination of Landsat digital data and aeromagnetic data has extended the use of Landsat as an exploration tool which can be used to readily relate surface features to subsurface anomalies.
\nMagsat data, now being collected, are helping refine information on major crustal anomalies that were first recognized during the analysis of POGO data. The more nearly circular orbit, lower altitude, and increased sophistication of its vector magnetometer enable Magsat to provide more precise information than POGO. Information of this type is required to develop crustal models. Although Magsat is designed to operate for only 4–8 months, the number of orbits that it should be able to make will be sufficient to accomplish its mission and to record a major magnetic storm expected in 1980.
\nHCMM is a two-band visible to near-IR (0.55–1.1 μm) and thermal infrared (10.2–12.5 μm) system designed to measure reflected solar energy, determine the heat capacity of rocks and to monitor soil moisture, thermal effluents, plant canopy temperatures and snow cover. Launched in April 1978, it is in sun-synchronous, circular orbit at an altitude of 620 km. It is a relatively low-resolution system with an instantaneous field of view (IFOV) of 500–600 m and a swath width of 716 km. However, the system is designed to detect objects in the range of 260°–340° K with a sensitivity (NEδT) of 0.4°K at 280°. Recording the thermal radiation of urban heat islands and high thermal inertia of quartzite strata in the Appalachian region are two examples of its land applications.
\nLaunched in June 1978, Seasat operated for only 100 days, but successfully acquired much information over both sea and land. The collection of synthetic aperture radar (SAR) imagery and radar altimetry was particularly important to geologists. Although there are difficulties in processing and distributing these data in a timely manner, initial evaluations indicate that the radar imagery supplements Landsat data by increasing the spectral range and offering a different look angle. The radar altimeter provides accurate profiles over narrow strips of land (1 km wide) and has demonstrated usefulness in measuring icecap surfaces (Greenland, Iceland, and Antarctica). The Salar of Uyuni in southern Bolivia served as a calibration site for the altimeter and has enabled investigators to develop a land-based smoothing algorithm that is believed to increase the accuracy of the system to 10 cm. Data from the altimeter are currently being used to measure subsidence resulting from ground water withdrawal in the Phoenix-Tucson area.
","language":"English","publisher":"Elsevier","doi":"10.1016/0273-1177(81)90402-6","issn":"02731177","usgsCitation":"Carter, W.D., 1981, Significant results from using earth observation satellites for mineral and energy resource exploration: Advances in Space Research, v. 1, no. 10, p. 261-269, https://doi.org/10.1016/0273-1177(81)90402-6.","productDescription":"9 p.","startPage":"261","endPage":"269","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":222,"text":"Earth Resources Observation and Science (EROS) Center","active":true,"usgs":true}],"links":[{"id":218640,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":266021,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0273-1177(81)90402-6"}],"volume":"1","issue":"10","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8f2de4b08c986b318d89","contributors":{"authors":[{"text":"Carter, William D.","contributorId":64567,"corporation":false,"usgs":true,"family":"Carter","given":"William","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":358640,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70011867,"text":"70011867 - 1981 - Magnetic signals from the core of the earth and secular variation","interactions":[],"lastModifiedDate":"2024-07-16T16:08:37.463196","indexId":"70011867","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":6453,"text":"Journal of Geophysical Research Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"Magnetic signals from the core of the earth and secular variation","docAbstract":"An oscillating, radial magnetic dipole source was assumed to exist in the core of the earth, 100 km beneath the core-mantle boundary. As an approximation, electromagnetic propagation was assumed in the core in lieu of hydromagnetic propagation, which could not be used because of unknown internal fields.Using Debye potentials, the radial and horizontal components of the surface fields were calculated using various assumed conductivity parameters in the core and in the mantle. It is concluded that most spherical harmonic models of the earth's magnetic field do not include enough terms to describe properly the field of core sources with periods of tens of years. These short-period variations are especially important in describing the secular variation. Because of this, a proper description of the secular variation requires more spherical harmonic terms than are required for the field itself. Inadequate representation of short-period variations in spherical harmonic models may contribute to the rapid deterioration of predictive models. Alternatives to spherical harmonic analysis for secular variation should be investigated; regardless of the method used, a much greater spatial distribution of high quality secular variation data is needed.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB086iB09p07957","issn":"01480227","usgsCitation":"Alldredge, L., 1981, Magnetic signals from the core of the earth and secular variation: Journal of Geophysical Research Solid Earth, v. 86, no. B9, p. 7957-7965, https://doi.org/10.1029/JB086iB09p07957.","productDescription":"9 p.","startPage":"7957","endPage":"7965","numberOfPages":"9","costCenters":[],"links":[{"id":220938,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"86","issue":"B9","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"505a4b81e4b0c8380cd695bd","contributors":{"authors":[{"text":"Alldredge, L.R.","contributorId":53457,"corporation":false,"usgs":true,"family":"Alldredge","given":"L.R.","email":"","affiliations":[],"preferred":false,"id":362156,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70010353,"text":"70010353 - 1981 - Role of solute-transport models in the analysis of groundwater salinity problems in agricultural areas","interactions":[],"lastModifiedDate":"2020-01-26T10:08:17","indexId":"70010353","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":680,"text":"Agricultural Water Management","active":true,"publicationSubtype":{"id":10}},"title":"Role of solute-transport models in the analysis of groundwater salinity problems in agricultural areas","docAbstract":"Undesirable salinity increases occur in both groundwater and surface water and are commonly related to agricultural practices. Groundwater recharge from precipitation or irrigation will transport and disperse residual salts concentrated by evapotranspiration, salts leached from soil and aquifer materials, as well as some dissolved fertilizers and pesticides. Where stream salinity is affected by agricultural practices, the increases in salt load usually are attributable mostly to a groundwater component of flow. Thus, efforts to predict, manage, or control stream salinity increases should consider the role of groundwater in salt transport. Two examples of groundwater salinity problems in Colorado, U.S.A., illustrate that a model which simulates accurately the transport and dispersion of solutes in flowing groundwater can be (1) a valuable investigative tool to help understand the processes and parameters controlling the movement and fate of the salt, and (2) a valuable management tool for predicting responses and optimizing the development and use of the total water resource.
","language":"English","publisher":"Elsevier","doi":"10.1016/0378-3774(81)90050-0","issn":"03783774","usgsCitation":"Konikow, L.F., 1981, Role of solute-transport models in the analysis of groundwater salinity problems in agricultural areas: Agricultural Water Management, v. 4, no. 1-3, p. 187-205, https://doi.org/10.1016/0378-3774(81)90050-0.","productDescription":"19 p.","startPage":"187","endPage":"205","numberOfPages":"19","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":219369,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Colorado","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -109.16015624999999,\n 37.055177106660814\n ],\n [\n -101.9970703125,\n 37.055177106660814\n ],\n [\n -101.9970703125,\n 41.11246878918088\n ],\n [\n -109.16015624999999,\n 41.11246878918088\n ],\n [\n -109.16015624999999,\n 37.055177106660814\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"4","issue":"1-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505aae6de4b0c8380cd870c8","contributors":{"authors":[{"text":"Konikow, Leonard F. 0000-0002-0940-3856 lkonikow@usgs.gov","orcid":"https://orcid.org/0000-0002-0940-3856","contributorId":158,"corporation":false,"usgs":true,"family":"Konikow","given":"Leonard","email":"lkonikow@usgs.gov","middleInitial":"F.","affiliations":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"preferred":true,"id":358700,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70012029,"text":"70012029 - 1981 - Sand waves on an epicontinental shelf: Northern Bering Sea","interactions":[],"lastModifiedDate":"2024-10-11T16:17:11.436108","indexId":"70012029","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2667,"text":"Marine Geology","active":true,"publicationSubtype":{"id":10}},"title":"Sand waves on an epicontinental shelf: Northern Bering Sea","docAbstract":"Sand waves and current ripples occupy the crests and flanks of a series of large linear sand ridges (20 km × 5 km × 10 m high) lying in an open-marine setting in the northern Bering Sea. The sand wave area, which lies west of Seward Peninsula and southeast of Bering Strait, is exposed to the strong continuous flow of coastal water northward toward Bering Strait. A hierarchy of three sizes of superimposed bedforms, all facing northward, was observed in successive cruises in 1976 and 1977. Large sand waves (height 2 m; spacing 200 m) have smaller sand waves (height 1 m; spacing 20 m) lying at a small oblique angle on their stoss slopes. The smaller sand waves in turn have linguoid ripples on their stoss slopes.
Repeated studies of the sand wave fields were made both years with high-resolution seismic-reflection profiles, side-scan sonographs, underwater photographs, current-meter stations, vibracores, and suspended-sediment samplers. Comparison of seismic and side-scan data collected along profile lines run both years showed changes in sand wave shape that indicate significant bedload transport within the year. Gouge marks made in sediment by keels of floating ice also showed significantly different patterns each year, further documenting modification to the bottom by sediment transport.
During calm sea conditions in 1977, underwater video and camera observations showed formation and active migration of linguoid and straight-crested current ripples. Current speeds 1 m above the bottom were between 20 and 30 cm/s. Maximum current velocities and sand wave migration apparently occur when strong southwesterly winds enhance the steady northerly flow of coastal water. Many cross-stratified sand bodies in the geologic record are interpreted as having formed in a tidal- or storm-dominated setting. This study provides an example of formation and migration of large bedforms by the interaction of storms with strong uniform coastal currents in an open-marine setting.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0070-4571(08)70301-7","usgsCitation":"Field, M.E., Nelson, C.H., Cacchione, D.A., and Drake, D.E., 1981, Sand waves on an epicontinental shelf: Northern Bering Sea: Marine Geology, v. 32, p. 233-258, https://doi.org/10.1016/S0070-4571(08)70301-7.","productDescription":"26 p.","startPage":"233","endPage":"258","numberOfPages":"26","costCenters":[],"links":[{"id":222454,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"32","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b869fe4b08c986b316043","contributors":{"authors":[{"text":"Field, Michael E. mfield@usgs.gov","contributorId":2101,"corporation":false,"usgs":true,"family":"Field","given":"Michael","email":"mfield@usgs.gov","middleInitial":"E.","affiliations":[{"id":520,"text":"Pacific Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":true,"id":362562,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Nelson, C. Hans","contributorId":34909,"corporation":false,"usgs":true,"family":"Nelson","given":"C.","email":"","middleInitial":"Hans","affiliations":[],"preferred":false,"id":362565,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Cacchione, David A.","contributorId":37327,"corporation":false,"usgs":true,"family":"Cacchione","given":"David","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":362564,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Drake, David E.","contributorId":74752,"corporation":false,"usgs":true,"family":"Drake","given":"David","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":362563,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70011870,"text":"70011870 - 1981 - Estimation of impervious-area washoff parameters","interactions":[],"lastModifiedDate":"2018-02-05T12:32:17","indexId":"70011870","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","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":"Estimation of impervious-area washoff parameters","docAbstract":"In recent years many models have been developed which simulate the quality of rainfall runoff from urban areas. Common to many of these models is the use of an exponential washoff equation. This washoff equation is often modified by an availability equation to account for the effects of runoff intensity on constituent washoff. Optimization techniques for estimating the values of coefficients used in these equations have been developed. Application of these techniques to a small urban watershed in south Florida demonstrated considerable variability in the optimized parameter values among different storms and among different constituents.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/WR017i004p01161","usgsCitation":"Alley, W.M., 1981, Estimation of impervious-area washoff parameters: Water Resources Research, v. 17, no. 4, p. 1161-1166, https://doi.org/10.1029/WR017i004p01161.","productDescription":"6 p.","startPage":"1161","endPage":"1166","costCenters":[],"links":[{"id":220999,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"17","issue":"4","noUsgsAuthors":false,"publicationDate":"2010-07-09","publicationStatus":"PW","scienceBaseUri":"505a0b94e4b0c8380cd527ab","contributors":{"authors":[{"text":"Alley, William M. walley@usgs.gov","contributorId":1661,"corporation":false,"usgs":true,"family":"Alley","given":"William","email":"walley@usgs.gov","middleInitial":"M.","affiliations":[{"id":502,"text":"Office of Surface Water","active":true,"usgs":true}],"preferred":false,"id":362159,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70012021,"text":"70012021 - 1981 - Dating of Archean basement in northeastern Wyoming and southern Montana.","interactions":[],"lastModifiedDate":"2013-02-24T08:44:50","indexId":"70012021","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","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":"Dating of Archean basement in northeastern Wyoming and southern Montana.","docAbstract":"Rb-Sr whole-rock and U-Pb zircon ages of granite and gneiss cores from three deep drill holes extend known occurrences of Archean rocks in the subsurface of NE Wyoming and S Montanta. Rb-Sr and K- Ar mineral ages are discordant and reflect early or middle Proterozoic disturbance. Highly altered rocks occur in a thin zone immediately below the sub-Cambrian unconformity. Samples from a few metres deeper in the basement are much fresher but show the effects of this alteration in filled fractures and thin adjacent alteration haloes. Whole-rock Rb-Sr systems have retaioned a fair degree of integrity in spite of increased susceptibility to modification because of the disturbed mineral systems. Interaction of the rocks with water a few metres below the sub-Cambrian unconformity probably occurred for only a relatively short time. Fractures filled rapidly with secondary minerals such as chlorite, anhydrite, and carbonate to maintain a relatively impermeable crystalline basement in which the silicates and their contained isotopic systems were preserved.- Author","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Geological Society of America Bulletin","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Geological Society of America","doi":"10.1130/0016-7606(1981)92<139:DOABIN>2.0.CO;2","usgsCitation":"Peterman, Z.E., 1981, Dating of Archean basement in northeastern Wyoming and southern Montana.: Geological Society of America Bulletin, v. 92, no. 3 pt 1, p. 139-146, https://doi.org/10.1130/0016-7606(1981)92<139:DOABIN>2.0.CO;2.","startPage":"139","endPage":"146","numberOfPages":"8","costCenters":[],"links":[{"id":222335,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":268108,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1130/0016-7606(1981)92<139:DOABIN>2.0.CO;2"}],"volume":"92","issue":"3 pt 1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fde1e4b0c8380cd4e9b3","contributors":{"authors":[{"text":"Peterman, Z. E.","contributorId":63781,"corporation":false,"usgs":true,"family":"Peterman","given":"Z.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":362537,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70012055,"text":"70012055 - 1981 - The Montenegro, Yugoslavia, earthquake of April 15, 1979: source orientation and strength","interactions":[],"lastModifiedDate":"2013-02-13T13:41:37","indexId":"70012055","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3071,"text":"Physics of the Earth and Planetary Interiors","active":true,"publicationSubtype":{"id":10}},"title":"The Montenegro, Yugoslavia, earthquake of April 15, 1979: source orientation and strength","docAbstract":"Long-period teleseismic P, S and Rayleigh waves and geologic considerations indicate that the Montenegro earthquake involved thrust faulting on a plane striking nearly parallel to the Adriatic coast and dipping ca. 15?? toward the Yugoslav mainland. There is some support from modeling of body waves recorded on long-period WWSSN instruments for a focal depth of 22 km, but the possibility of a multiple source and the difficulty of matching some of the detailed characteristics of the P- and S-wave forms reduce our confidence in the determination of the depth. Fortunately, the source orientation and moment of the event are not sensitive functions of the depth. The long-period (256 s) moment was 4.6 ?? 1019 Nm (4.6 ?? 1026 dyne-cm). The moment obtained by fitting the first cycle of P and S waves recorded on WWSSN long-period instruments is about four times smaller. This increase of moment with period is consistent with spectral estimates of the moment from SH waves recorded at SRO and ASRO stations. ?? 1981.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Physics of the Earth and Planetary Interiors","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier","publisherLocation":"Amsterdam, Netherlands","doi":"10.1016/0031-9201(81)90041-8","issn":"00319201","usgsCitation":"Boore, D., Sims, J., Kanamori, H., and Harding, S., 1981, The Montenegro, Yugoslavia, earthquake of April 15, 1979: source orientation and strength: Physics of the Earth and Planetary Interiors, v. 27, no. 2, p. 133-142, https://doi.org/10.1016/0031-9201(81)90041-8.","startPage":"133","endPage":"142","numberOfPages":"10","costCenters":[],"links":[{"id":221863,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":267346,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0031-9201(81)90041-8"}],"volume":"27","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505ba800e4b08c986b32194c","contributors":{"authors":[{"text":"Boore, D.M. 0000-0002-8605-9673","orcid":"https://orcid.org/0000-0002-8605-9673","contributorId":64226,"corporation":false,"usgs":true,"family":"Boore","given":"D.M.","affiliations":[],"preferred":false,"id":362628,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sims, J.D.","contributorId":9230,"corporation":false,"usgs":false,"family":"Sims","given":"J.D.","email":"","affiliations":[],"preferred":false,"id":362625,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kanamori, H.","contributorId":55438,"corporation":false,"usgs":true,"family":"Kanamori","given":"H.","affiliations":[],"preferred":false,"id":362627,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Harding, S.","contributorId":15469,"corporation":false,"usgs":true,"family":"Harding","given":"S.","email":"","affiliations":[],"preferred":false,"id":362626,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70030355,"text":"70030355 - 1981 - Simulation model of Skeletonema costatum population dynamics in northern San Francisco Bay, California","interactions":[],"lastModifiedDate":"2023-10-12T17:04:25.404413","indexId":"70030355","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1587,"text":"Estuarine, Coastal and Shelf Science","active":true,"publicationSubtype":{"id":10}},"displayTitle":"Simulation model of Skeletonema costatum population dynamics in northern San Francisco Bay, California","title":"Simulation model of Skeletonema costatum population dynamics in northern San Francisco Bay, California","docAbstract":"A pseudo-two-dimensional model is developed to simulate population dynamics of one dominant phytoplankton species (Skeletonema costatum) in northern San Francisco Bay. The model is formulated around a conceptualization of this estuary as two distinct but coupled subsystems—a deep (10–20 m) central channel and lateral areas with shallow (<2 m) water and slow circulation. Algal growth rates are governed by solar irradiation, temperature and salinity, while population losses are assumed to result from grazing bycalanoid copepods. Consequences of estuarine gravitational circulation are approximated simply by reducing convective-dispersive transport in that section of the channel (null zone) where residual bottom currents are near zero, and lateral mixing is treated as a bulkexchange process between the channel and the shoals.
Model output is consistent with the hypothesis that, because planktonic algae are light-limited, shallow areas are the sites of active population growth. Seasonal variation in the location of the null zone (a response to variable river discharge) is responsible for maintaining the spring bloom of neritic diatoms in the seaward reaches of the estuary (San Pablo Bay) and the summer bloom upstream (Suisun Bay). Model output suggests that these spring and summer blooms result from the same general process—establishment of populations over the shoals, where growth rates are rapid, coupled with reduced particulate transport due to estuarine gravitational circulation. It also suggests, however, that the relative importance of physical and biological processes to phytoplankton dynamics is different in San Pablo and Suisun Bays. Finally, the model has helped us determine those processes having sufficient importance to merit further refinement in the next generation of models, and it has given new direction to field studies.
An atomic-absorption spectrophotometric method with electrothermal atomisation has been developed for the determination of selenium in geological materials. The sample is decomposed with a mixture of nitric, perchloric and hydrofluoric acids and heated with hydrochloric acid to reduce selenium to selenium(IV). Selenium is then extracted into toluene from a hydrochloric acid-hydrobromic acid medium containing iron. A few micro-litres of the toluene extract are injected into a carbon rod atomiser, using a nickel solution as a matrix modifier. The limits of determination are 0.2–200 p.p.m. of selenium in a geological sample. For concentrations between 0.05 and 0.2 p.p.m., back-extraction of the selenium into dilute hydrochloric acid is employed before atomisation.
Selenium values for reference samples obtained by replicate analysis are in general agreement with those reported by other workers, with relative standard deviations ranging from 4.1 to 8.8%. Recoveries of selenium spiked at two levels were 98–108%. Major and trace elements commonly encountered in geological materials do not interfere. Arsenic has a suppressing effect on the selenium signals, but only when its concentration is greater than 1 000 p.p.m. Nitric acid interferes seriously with the extraction of selenium and must be removed by evaporation in the sample-digestion step.
","language":"English","publisher":"Royal Society of Chemistry","doi":"10.1039/AN9810600647","issn":"00032654","usgsCitation":"Sanzolone, R.F., and Chao, T.T., 1981, Determination of sub-microgram amounts of selenium in geological materials by atomic-absorption spectrophotometry with electrothermal atomisation after solvent extraction: The Analyst, v. 106, no. 1263, p. 647-652, https://doi.org/10.1039/AN9810600647.","productDescription":"6 p.","startPage":"647","endPage":"652","numberOfPages":"6","costCenters":[],"links":[{"id":222521,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"106","issue":"1263","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ffcbe4b0c8380cd4f3d6","contributors":{"authors":[{"text":"Sanzolone, R. F.","contributorId":64199,"corporation":false,"usgs":true,"family":"Sanzolone","given":"R.","middleInitial":"F.","affiliations":[],"preferred":false,"id":362852,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Chao, T. T.","contributorId":31900,"corporation":false,"usgs":true,"family":"Chao","given":"T.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":362851,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70011716,"text":"70011716 - 1981 - Chemistry of rock-forming minerals of the Cretaceous-Paleocene batholith in southwestern Japan and implications for magma genesis","interactions":[],"lastModifiedDate":"2024-07-16T16:26:01.668394","indexId":"70011716","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":6453,"text":"Journal of Geophysical Research Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"Chemistry of rock-forming minerals of the Cretaceous-Paleocene batholith in southwestern Japan and implications for magma genesis","docAbstract":"Petrographic descriptions and electron microprobe analyses of minerals are presented for 35 specimens from seven suites chosen to examine the transition from magnetite series to ilmenite series granitoids along two transects across the Cretaceous-Paleocene Inner Zone batholith of southwestern Japan. Regularities in chemical compositions of amphiboles, biotites, and feldspars suggest that fundamentally similar processes produced the magmas that formed the two series. Constant or decreasing Fe/(Fe+Mg) for biotites and amphiboles with increasing host rock silica content, coupled with the absence of early formed magnetite and sphene, suggest that magnetite series rocks may have become oxidized during crystallization near the level of intrusion, through the processes of second boiling and differential loss of hydrogen. For the Daito-Yokota, magnetite series suite, Fe/(Fe+Mg) for biotites decreased from 0.48 to 0.37 as SiO2 content of the host rock increased from 55.3 to 75.5 wt %; for an ilmenite series suite from the Takanawa Peninsula, Fe/(Fe+Mg) for biotites increased from 0.51 to 0.77 with an increase in host rock SiO2 from 53.4 to 75.5. Detailed consideration of amphibole chemistry shows predominance of edenitic and tschermakitic substitution schemes as well as coupling between substitutions of Ti in octahedral sites and AlIV. Interrelations between amphibole and biotite chemistry show that Fe/(Fe+Mg) and Mn contents can be interpreted in terms of equilibration, whereas Ti content cannot. The chemistry of chlorites correlates well with that of biotites; primary and secondary muscovites are distinct in composition. Plagioclase in all studied suites shows igneous zoning appropriate to host rock composition; perthitic alkali feldspars in all samples have lost albite component, and temperatures based on the two-feldspar geothermometer are low. The biotite-apatite geothermometer is also inoperative for this group of samples because fully fluorinated apatites typically occur in biotites of modest F content. Whereas magnetites have reequilibrated, analyses of ilmenites for the representative Daito-Yokota and Takanawa suites corroborate biotite compositional data and suggest that fO2 probably differed by 2 to 3 orders of magnitude during crystallization of silica-rich magnetite and ilmenite series granites. Whole-rock chemistry supports mineral chemistry in suggesting that the studied granitoids have crystallized from magmas generated in a lower crustal environment in which mantle-derived magmas partially melted source materials with igneous characteristics.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB086iB11p10431","issn":"01480227","usgsCitation":"Czamanske, G., Ishihara, S., and Atkin, S., 1981, Chemistry of rock-forming minerals of the Cretaceous-Paleocene batholith in southwestern Japan and implications for magma genesis: Journal of Geophysical Research Solid Earth, v. 86, no. B11, p. 10431-10469, https://doi.org/10.1029/JB086iB11p10431.","productDescription":"39 p.","startPage":"10431","endPage":"10469","numberOfPages":"39","costCenters":[],"links":[{"id":221465,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"86","issue":"B11","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"5059f5abe4b0c8380cd4c360","contributors":{"authors":[{"text":"Czamanske, G.K.","contributorId":26300,"corporation":false,"usgs":true,"family":"Czamanske","given":"G.K.","email":"","affiliations":[],"preferred":false,"id":361791,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ishihara, S.","contributorId":83269,"corporation":false,"usgs":true,"family":"Ishihara","given":"S.","email":"","affiliations":[],"preferred":false,"id":361793,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Atkin, S.A.","contributorId":79621,"corporation":false,"usgs":true,"family":"Atkin","given":"S.A.","email":"","affiliations":[],"preferred":false,"id":361792,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70012124,"text":"70012124 - 1981 - Chemical constraints of groundwater management in the Yucatan peninsula, Mexico","interactions":[],"lastModifiedDate":"2019-12-06T07:03:57","indexId":"70012124","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","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":"Chemical constraints of groundwater management in the Yucatan peninsula, Mexico","docAbstract":"Two critical objectives of water management in the Yucatan are: (1) to develop regional groundwater supplies for an expanding population and tourism based on the Mayan archeological sites and excellent beaches; and (2) to control groundwater pollution in a chemically sensitive system made vulnerable by geologic conditions.
The Yucatan peninsula is a coastal plain underlain by permeable limestone and has an annual rainfall of more than 1000 mm. Such a setting should provide abundant supplies of water; however, factors of climate and hydrogeology have combined to form a hydrologic system with chemical boundaries that decrease the amount of available fresh water.
Management of water resources has long had a major influence on the cultural and economic development of the Yucatan. The Mayan culture of the northern Yucatan developed by extensive use of groundwater. The religion was water-oriented and the Mayan priests prayed to Chac, the water god, for assistance in water management primarily to decrease the severity of droughts. The Spaniards arrived in 1517 and augmented the supplies by digging wells, which remained the common practice for more than 300 years. Many wells now have been abandoned because of serious problems of pollution resulting from the use of a sewage disposal well adjacent to each supply well.
The modern phase of water management began in 1959 when the Secretaría de Recursos Hidráulicos (S.R.H.) was charged with the responsibility for both scientific investigations and development programmes for water-supply and sewage-disposal systems for cities, villages and islands.
Metamorphosed Mesozoic volcanic rocks from the east-central Sierra Nevada range in composition from basalt to rhyolite and have ages, based on whole rock Rb-Sr and U-Pb zircon dating, of about 237–224, 185, 163, 134, and 100 m.y. The major plutons of the batholith in this area are of Triassic (215–200 m.y.) and Cretaceous (94–80 m.y.) ages. Initial 87Sr/86Sr values for the metamorphosed volcanic rocks of the area are in the range from 0.7042 to 0.7058 and are generally different from the values for the surrounding batholithic rocks (0.7056–0.7066). A circular, zoned granitic pluton, with an outcrop area of 2.5 km2, similar in appearance to a ring dike complex, was apparently a conduit for some or possibly all of the middle-Cretaceous metamorphosed volcanic rocks exposed about 5 km to the south in the western part of the Ritter Range. Samples from the metamorphosed volcanic rocks and the pluton yield a Rb-Sr whole rock isochron age of 99.9 ± 2.2 m.y. with an initial 87Sr/86Sr of 0.7048 ± 0.0001. Major element variation diagrams of the pluton and volcanic rocks define coincident compositional trends. The pluton, intruded into Early Jurassic metamorphosed volcanic rocks (Rb-Sr whole rock isochron age of 185 ± 6 m.y., initial 87/86Sr = 0.70474 ± 0.00009), is composed of a central body of granite that is intruded into and almost completely surrounded by a crescent-shaped outer rim of quartz monzodiorite. Contact relations between the granitic rocks, intrusive in some places and completely gradational at other places, indicate that the quartz monzodiorite was not completely crystallized prior to the intrusion of the granite. Modal minerology within the pluton is also consistent with this inferred crystallization history. The granitic rock textures are cataclastic, characterized by a groundmass of feldspar and quartz that surrounds larger grains of feldspar, hornblende, and biotite. Widely spaced aplite dikes from the granite intrude the quartz monzodiorite along the contact between the granitic rocks. The aplite dikes and interstitial alkali feldspar associated with myrmekite in the pluton, being undeformed, indicate crystallization of a small amount of silicate liquid after cataclasis. Aplite compositions suggest a minimum crystallization pressure of 0.5 kb (1–2 km); this depth is consistent with crystallization near the base of a large stratovolcano. The pluton is characterized by steep, linear features, defined by mineral clots and inclusions, that probably formed during the upward movement of the nearly crystallized magma in the volcanic conduit. The ages of volcanic events relative to the ages of the major intrusive epochs and the major element and isotopic compositions of the volcanic rocks relative to the major plutons indicate that the volcanic rocks are not simply or directly related to the major plutons in the Sierra Nevada.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/JB086iB11p10489","issn":"01480227","usgsCitation":"Kistler, R.W., and Swanson, S., 1981, Petrology and geochronology of metamorphosed volcanic rocks and a middle Cretaceous volcanic neck in the east-central Sierra Nevada, California: Journal of Geophysical Research Solid Earth, v. 86, no. B11, p. 10489-10501, https://doi.org/10.1029/JB086iB11p10489.","productDescription":"13 p.","startPage":"10489","endPage":"10501","numberOfPages":"13","costCenters":[],"links":[{"id":221611,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"86","issue":"B11","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"505a7820e4b0c8380cd78641","contributors":{"authors":[{"text":"Kistler, R. W.","contributorId":36112,"corporation":false,"usgs":true,"family":"Kistler","given":"R.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":361930,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Swanson, S.E.","contributorId":84505,"corporation":false,"usgs":true,"family":"Swanson","given":"S.E.","email":"","affiliations":[],"preferred":false,"id":361931,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70011987,"text":"70011987 - 1981 - Crystal growth of calcite from calcium bicarbonate solutions at constant PCO2 and 25°C: a test of a calcite dissolution model","interactions":[],"lastModifiedDate":"2018-03-21T15:10:31","indexId":"70011987","displayToPublicDate":"1981-01-01T00:00:00","publicationYear":"1981","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":"Crystal growth of calcite from calcium bicarbonate solutions at constant PCO2 and 25°C: a test of a calcite dissolution model","docAbstract":"A highly reproducible seeded growth technique was used to study calcite crystallization from calcium bicarbonate solutions at 25°C and fixed carbon dioxide partial pressures between 0.03 and 0.3 atm. The results are not consistent with empirical crystallization models that have successfully described calcite growth at low PCO2 (< 10−3 atm). Good agreement was found between observed crystallization rates and those calculated from the calcite dissolution rate law and mechanism proposed by Plummer et al. (1978).
","language":"English","publisher":"Elsevier","doi":"10.1016/0016-7037(81)90222-2","issn":"00167037","usgsCitation":"Reddy, M.M., Plummer, N., and Busenberg, E., 1981, Crystal growth of calcite from calcium bicarbonate solutions at constant PCO2 and 25°C: a test of a calcite dissolution model: Geochimica et Cosmochimica Acta, v. 45, no. 8, p. 1281-1289, https://doi.org/10.1016/0016-7037(81)90222-2.","productDescription":"9 p.","startPage":"1281","endPage":"1289","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":220730,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"45","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fcfbe4b0c8380cd4e565","contributors":{"authors":[{"text":"Reddy, Michael M. mmreddy@usgs.gov","contributorId":684,"corporation":false,"usgs":true,"family":"Reddy","given":"Michael","email":"mmreddy@usgs.gov","middleInitial":"M.","affiliations":[{"id":145,"text":"Branch of Regional Research-Central Region","active":false,"usgs":true}],"preferred":true,"id":362456,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Plummer, Niel 0000-0002-4020-1013 nplummer@usgs.gov","orcid":"https://orcid.org/0000-0002-4020-1013","contributorId":190100,"corporation":false,"usgs":true,"family":"Plummer","given":"Niel","email":"nplummer@usgs.gov","affiliations":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"preferred":true,"id":362458,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Busenberg, E.","contributorId":56796,"corporation":false,"usgs":true,"family":"Busenberg","given":"E.","affiliations":[],"preferred":false,"id":362457,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ]}