The lithology and structural features of the Ahuachapán geothermal area and their impact on the movement of cold and hot fluids within the system are described, as well as the development and evaluation of the natural state model of the field. Four major lithologic units are present in Ahuachapán and three major aquifers have been identified; flow patterns and zones of fluid mixing were located on the basis of temperature and geochemical data from wells and surface manifestations. Geologic structures control the heat and fluid recharge and the flow within the reservoir. Modeling studies suggest, in agreement with field data, an overall average transmissivity of 25–35 darcy-meters, and indicate that the system is recharged by waters with temperatures greater than 250°C. The total thermal throughflow for the Ahuachapán reservoir in the unexploited state is estimated to be about 250 MWt.
","language":"English","publisher":"Elsevier","doi":"10.1016/0375-6505(91)90002-D","issn":"03756505","usgsCitation":"Aunzo, Z., Laky, C., Steingrimsson, B., Bodvarsson, G., Lippmann, M., Truesdell, A., Escobar, C., Quintanilla, A., and Cuellar, G., 1991, Pre-exploitation state of the Ahuachapán geothermal field, El Salvador: Geothermics, v. 20, no. 1-2, p. 1-22, https://doi.org/10.1016/0375-6505(91)90002-D.","productDescription":"22 p.","startPage":"1","endPage":"22","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":224284,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"20","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a80dce4b0c8380cd7b243","contributors":{"authors":[{"text":"Aunzo, Z.","contributorId":101020,"corporation":false,"usgs":true,"family":"Aunzo","given":"Z.","email":"","affiliations":[],"preferred":false,"id":369817,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Laky, C.","contributorId":26193,"corporation":false,"usgs":true,"family":"Laky","given":"C.","email":"","affiliations":[],"preferred":false,"id":369811,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Steingrimsson, B.","contributorId":98884,"corporation":false,"usgs":true,"family":"Steingrimsson","given":"B.","email":"","affiliations":[],"preferred":false,"id":369816,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Bodvarsson, G.S.","contributorId":98045,"corporation":false,"usgs":true,"family":"Bodvarsson","given":"G.S.","email":"","affiliations":[],"preferred":false,"id":369815,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Lippmann, M.J.","contributorId":66423,"corporation":false,"usgs":true,"family":"Lippmann","given":"M.J.","email":"","affiliations":[],"preferred":false,"id":369814,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Truesdell, A.H.","contributorId":52566,"corporation":false,"usgs":false,"family":"Truesdell","given":"A.H.","email":"","affiliations":[{"id":6672,"text":"former: USGS Southwest Biological Science Center, Colorado Plateau Research Station, Flagstaff, AZ. Current address: TN-SCORE, Univ of Tennessee, Knoxville, TN, e-mail: jennen@gmail.com","active":true,"usgs":false}],"preferred":false,"id":369813,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Escobar, C.","contributorId":18513,"corporation":false,"usgs":true,"family":"Escobar","given":"C.","email":"","affiliations":[],"preferred":false,"id":369809,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Quintanilla, A.","contributorId":45056,"corporation":false,"usgs":true,"family":"Quintanilla","given":"A.","email":"","affiliations":[],"preferred":false,"id":369812,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Cuellar, G.","contributorId":22094,"corporation":false,"usgs":true,"family":"Cuellar","given":"G.","email":"","affiliations":[],"preferred":false,"id":369810,"contributorType":{"id":1,"text":"Authors"},"rank":9}]}} ,{"id":70015005,"text":"70015005 - 1991 - A Sr-isotopic comparison between thermal waters, rocks, and hydrothermal calcites, Long Valley caldera, California","interactions":[],"lastModifiedDate":"2012-03-12T17:18:59","indexId":"70015005","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2499,"text":"Journal of Volcanology and Geothermal Research","active":true,"publicationSubtype":{"id":10}},"title":"A Sr-isotopic comparison between thermal waters, rocks, and hydrothermal calcites, Long Valley caldera, California","docAbstract":"The 87Sr/86Sr values of thermal waters and hydrothermal calcites of the Long Valley caldera geothermal system are more radiogenic than those of young intracaldera volcanic rocks. Five thermal waters display 87Sr/86Sr of 0.7081-0.7078 but show systematically lighter values from west to east in the direction of lateral flow. We believe the decrease in ratio from west to east signifies increased interaction of deeply circulating thermal water with relatively fresh volcanic rocks filling the caldera depression. All types of pre-, syn-, and post-caldera volcanic rocks in the west and central caldera have (87Sr/86Sr)m between about 0.7060 and 0.7072 and values for Sierra Nevada granodiorites adjacent to the caldera are similar. Sierran pre-intrusive metavolcanic and metasedimentary rocks can have considerably higher Sr-isotope ratios (0.7061-0.7246 and 0.7090-0.7250, respectively). Hydrothermally altered volcanic rocks inside the caldera have (87Sr/86Sr)m slightly heavier than their fresh volcanic equivalents and hydrothermal calcites (0.7068-0.7105) occupy a midrange of values between the volcanic/plutonic rocks and the Sierran metamorphic rocks. These data indicate that the Long Valley geothermal reservoir is first equilibrated in a basement complex that contains at least some metasedimentary rocks. Reequilibration of Sr-isotope ratios to lower values occurs in thermal waters as convecting geothermal fluids flow through the isotopically lighter volcanic rocks of the caldera fill. ?? 1991.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Volcanology and Geothermal Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"03770273","usgsCitation":"Goff, F., Wollenberg, H., Brookins, D., and Kistler, R.W., 1991, A Sr-isotopic comparison between thermal waters, rocks, and hydrothermal calcites, Long Valley caldera, California: Journal of Volcanology and Geothermal Research, v. 48, no. 3-4, p. 265-281.","startPage":"265","endPage":"281","numberOfPages":"17","costCenters":[],"links":[{"id":224344,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"48","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e308e4b0c8380cd45db5","contributors":{"authors":[{"text":"Goff, F.","contributorId":53408,"corporation":false,"usgs":true,"family":"Goff","given":"F.","email":"","affiliations":[],"preferred":false,"id":369832,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wollenberg, H.A.","contributorId":96681,"corporation":false,"usgs":true,"family":"Wollenberg","given":"H.A.","email":"","affiliations":[],"preferred":false,"id":369834,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Brookins, D.C.","contributorId":57727,"corporation":false,"usgs":true,"family":"Brookins","given":"D.C.","email":"","affiliations":[],"preferred":false,"id":369833,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Kistler, R. W.","contributorId":36112,"corporation":false,"usgs":true,"family":"Kistler","given":"R.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":369831,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70015007,"text":"70015007 - 1991 - U-series ages of solitary corals from the California coast by mass spectrometry","interactions":[],"lastModifiedDate":"2024-04-12T15:28:14.112152","indexId":"70015007","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","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":"U-series ages of solitary corals from the California coast by mass spectrometry","docAbstract":"The purpose of this study is to evaluate the feasibility of dating fossil solitary corals from Pleistocene marine strandlines outside tropical latitudes using the recently developed high sensitivity, high-precision U-series technique based on thermal-ionization mass-spectrometry (TIMS). The TIMS technique is much more efficient than conventional a spectrometry and, as a result, multiple samples of an individual coral skeleton, or different specimens from the same bed can be analyzed.
Detached and well-rounded fossil specimens of the solitary coral Balanophyllia elegans were collected from relict littoral deposits on emergent marine terraces along the California coast at Cayucos terrace (elevation 8 m, previously dated at 124 and 117 Ky by α counting), Shell Beach terrace (elevation about 25 m, previously undated), Nestor terrace, San Diego (elevation 23 m, previously dated at 131 to 109 Ky ), Bird Rock terrace, San Diego ( elevation 8 m, previously dated at 81 Ky ). Attached living specimens were collected from the intertidal zone on the modern terrace at Moss Beach.
Concentrations of 232Th in both living and fossil specimens are much higher than in reef-building corals (12 to 624 pmol/g vs. 0.1 to 1.6 pmol/g, respectively). However, because 230Th/232Th in Balanophyllia elegans are very low (2.22 × 10−3to 4.33 × 10−4), the high 232Th concentrations have negligible effect on the 230Th-234U dates. The high 232Th concentration in the living specimen (33.1 pmol/g) indicates that a significant amount of 232Th is incorporated in the aragonitic skeleton during growth, or attached to clay-sized silicates trapped in the skeletal material. The calculated initial 234U activities in the fossil specimens of Balanophyllia elegans are higher than the 234U activity in modern seawater or in the modern specimen. The higher initial activities could possibly reflect the influx of 234U-enriched continental water into Pleistocene coastal waters, or it could reflect minor diagenetic alteration, a persistent and fundamental problem in dating all corals.
Samples from a compound specimen from the Cayucos terrace were subjected to different preparation procedures. Samples prepared by a standard acid washing procedure yielded 230Th-234U ages of 125, 123, and 122 Ky, whereas samples prepared by an abbreviated procedure without acid washing yield significantly lower ages of 113 and 112 Ky. Two other specimens from the same bed yielded 230Th-234U ages of 118 and 115 Ky. Also, two specimens from a stratigraphically higher bed yielded ages of 120 and 117 Ky, and three specimens from a lower bed yield ages of 115, 113, and 101 Ky. Nine of the twelve ages of the treated samples from the Cayucos terrace range from 125 to 113 Ky. However, the ages do not follow the stratigraphie order. Two possible interpretations are ( 1 ) the age of the terrace deposit is 125 Ky and all younger ages reflect variable diagenetic alteration or (2) the age of the terrace is 125 to 113 Ky and the ages reflect sediment reworking over a period of 12 Ky.
Three specimens from a single bed on the Shell Beach terrace yield ages of 126, 122, and 121 Ky, similar to the older ages from Cayucos. The ages of solitary corals from the Cayucos and Shell Beach terraces are similar to ages of reef-building corals from terraces at numerous tropical localities. These are correlated with the last interglacial sea-level highstand, which probably stood 2 to 10 m above present sea level. The youngest ages and present elevations of the Cayucos and Shell Beach terraces yield tectonic uplift rates of 0.01 and 0.15 m/Ky, respectively, assuming the original elevation of each terrace was 7 m.
Four specimens from the basal gravel on the Nestor terrace yielded ages of 145, 143, 137, and 133 Ky. The three oldest ages, however, are older than that associated with the last interglacial. The possible explanations for these older ages are ( 1 ) diagenic alteration or ( 2 ) the Nestor terrace deposits reflect in some way a poorly documented early phase of the last interglacial sea level high stand.
","language":"English","publisher":"Elsevier","doi":"10.1016/0016-7037(91)90069-H","issn":"00167037","usgsCitation":"Stein, M., Wasserburg, G., Lajoie, K.R., and Chen, J., 1991, U-series ages of solitary corals from the California coast by mass spectrometry: Geochimica et Cosmochimica Acta, v. 55, no. 12, p. 3709-3722, https://doi.org/10.1016/0016-7037(91)90069-H.","productDescription":"14 p.","startPage":"3709","endPage":"3722","numberOfPages":"14","costCenters":[],"links":[{"id":224397,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"55","issue":"12","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bb9e4e4b08c986b327eac","contributors":{"authors":[{"text":"Stein, Martin","contributorId":28055,"corporation":false,"usgs":true,"family":"Stein","given":"Martin","email":"","affiliations":[],"preferred":false,"id":369840,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wasserburg, G.J.","contributorId":54734,"corporation":false,"usgs":true,"family":"Wasserburg","given":"G.J.","email":"","affiliations":[],"preferred":false,"id":369841,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lajoie, K. R.","contributorId":6828,"corporation":false,"usgs":true,"family":"Lajoie","given":"K.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":369839,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Chen, J.-H.","contributorId":61278,"corporation":false,"usgs":true,"family":"Chen","given":"J.-H.","affiliations":[],"preferred":false,"id":369842,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70015015,"text":"70015015 - 1991 - Changes in thermodynamic conditions of the Ahuachapán reservoir due to production and injection","interactions":[],"lastModifiedDate":"2015-05-29T10:53:46","indexId":"70015015","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1828,"text":"Geothermics","active":true,"publicationSubtype":{"id":10}},"title":"Changes in thermodynamic conditions of the Ahuachapán reservoir due to production and injection","docAbstract":"Since large-scale exploitation of the Ahuachapán reservoir began in 1975 large changes in the reservoir thermodynamic conditions have occurred. Drawdown of up to 15 bars and significant temperature changes have been observed in the wellfield. Temperatures have declined due to boiling in the reservoir in response to the pressure drawdown; localized and minor cooling due to reinjection of spent geothermal fluids have also been observed. There are indications of cold fluid influx deep into the reservoir from the west and north. Reservoir temperatures show that a significant amount of hot fluid recharge comes to the wellfield from the southeast, and temperatures also indicate that the recharge rate has increased with time as pressure declines in the reservoir. Chemical analyses of the produced fluids show that most wells are fed by a mixture of geothermal fluids and cooler, less-saline waters. The cold water inflow has increased due to exploitation, as demonstrated by decreased salinity of the produced fluids.
","language":"English","doi":"10.1016/0375-6505(91)90003-E","issn":"03756505","usgsCitation":"Steingrimsson, B., Aunzo, Z., Bodvarsson, G., Truesdell, A., Cuellar, G., Escobar, C., and Quintanilla, A., 1991, Changes in thermodynamic conditions of the Ahuachapán reservoir due to production and injection: Geothermics, v. 20, no. 1-2, p. 23-38, https://doi.org/10.1016/0375-6505(91)90003-E.","productDescription":"16 p.","startPage":"23","endPage":"38","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":479732,"rank":1,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"https://escholarship.org/uc/item/1k97077w","text":"External Repository"},{"id":223577,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"20","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f437e4b0c8380cd4bbec","contributors":{"authors":[{"text":"Steingrimsson, B.","contributorId":98884,"corporation":false,"usgs":true,"family":"Steingrimsson","given":"B.","email":"","affiliations":[],"preferred":false,"id":369864,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Aunzo, Z.","contributorId":101020,"corporation":false,"usgs":true,"family":"Aunzo","given":"Z.","email":"","affiliations":[],"preferred":false,"id":547867,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bodvarsson, G.S.","contributorId":98045,"corporation":false,"usgs":true,"family":"Bodvarsson","given":"G.S.","email":"","affiliations":[],"preferred":false,"id":369863,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Truesdell, A.","contributorId":51919,"corporation":false,"usgs":true,"family":"Truesdell","given":"A.","affiliations":[],"preferred":false,"id":547868,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Cuellar, G.","contributorId":22094,"corporation":false,"usgs":true,"family":"Cuellar","given":"G.","email":"","affiliations":[],"preferred":false,"id":369860,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Escobar, C.","contributorId":18513,"corporation":false,"usgs":true,"family":"Escobar","given":"C.","email":"","affiliations":[],"preferred":false,"id":369859,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Quintanilla, A.","contributorId":45056,"corporation":false,"usgs":true,"family":"Quintanilla","given":"A.","email":"","affiliations":[],"preferred":false,"id":547869,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":70015017,"text":"70015017 - 1991 - Convergent radial dispersion: A note on evaluation of the Laplace transform solution","interactions":[],"lastModifiedDate":"2019-03-28T06:18:34","indexId":"70015017","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","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":"Convergent radial dispersion: A note on evaluation of the Laplace transform solution","docAbstract":"A numerical inversion algorithm for Laplace transforms that is capable of handling rapid changes in the computed function is applied to the Laplace transform solution to the problem of convergent radial dispersion in a homogeneous aquifer. Prior attempts by the author to invert this solution were unsuccessful for highly advective systems where the Peclet number was relatively large. The algorithm used in this note allows for rapid and accurate inversion of the solution for all Peclet numbers of practical interest, and beyond. Dimensionless breakthrough curves are illustrated for tracer input in the form of a step function, a Dirac impulse, or a rectangular input.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/91WR02301","usgsCitation":"Moench, A.F., 1991, Convergent radial dispersion: A note on evaluation of the Laplace transform solution: Water Resources Research, v. 27, no. 12, p. 3261-3264, https://doi.org/10.1029/91WR02301.","productDescription":"4 p.","startPage":"3261","endPage":"3264","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":223631,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"27","issue":"12","noUsgsAuthors":false,"publicationDate":"2008-01-08","publicationStatus":"PW","scienceBaseUri":"5059fbd7e4b0c8380cd4dfd6","contributors":{"authors":[{"text":"Moench, Allen F. afmoench@usgs.gov","contributorId":3903,"corporation":false,"usgs":true,"family":"Moench","given":"Allen","email":"afmoench@usgs.gov","middleInitial":"F.","affiliations":[],"preferred":true,"id":369869,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70015019,"text":"70015019 - 1991 - Estimation of suspended-sediment rating curves and mean suspended-sediment loads","interactions":[],"lastModifiedDate":"2016-06-01T16:17:53","indexId":"70015019","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","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":"Estimation of suspended-sediment rating curves and mean suspended-sediment loads","docAbstract":"Suspended-sediment loads are often estimated from an empirical relation between suspended-sediment load (L) and streamflow (S). This relation is usually defined as a power function, L = aSh, and is referred to as a suspended-sediment rating curve. This function can be formulated as either a linear or non-linear model to find the solution of the rating-curve parameters (a and b). Formulation of the power function as a linear model requires a logarithmic transformation to linearize the function and a subsequent correction for transformation bias. Rating-curve parameter estimates for both the bias-corrected, transformed-linear or non-linear models can be obtained by the method of least squares.
\nEach model has distinct advantages and disadvantages. A unique solution of the parameters of the transformed-linear model may be obtained algebraically. These parameter estimates have some optimal properties when certain attainable conditions are met. However, the parameter estimates must be corrected for transformation bias when obtained this way. Parameter estimates obtained for the non-linear model do not require a correction for transformation bias. However, these estimates must be obtained by iterative methods which do not always converge to a solution. In addition, the residual errors of the non-linear model typically are not identically distributed throughout the range of streamflow values. This problem adversely affects the precision of the parameter estimates. Weighted non-linear least squares can be used to improve the parameter estimates for the non-linear model, but the weights must be approximated and their appropriate form may be difficult to determine.
\nA simulation study was done to evaluate: (1) the accuracy and precision of parameter estimates for the bias-corrected, transformed-linear and non-linear models obtained by the method of least squares; (2) the accuracy of mean suspended-sediment loads calculated by the flow-duration, rating-curve method using model parameters obtained by the alternative methods. Parameter estimates obtained by least squares for the bias-corrected, transformed-linear model were considerably more precise than those obtained for the non-linear or weighted non-linear model. The accuracy of parameter estimates obtained for the biascorrected, transformed-linear and weighted non-linear model was similar and was much greater than the accuracy obtained by non-linear least squares. The improved parameter estimates obtained by the biascorrected, transformed-linear or weighted non-linear model yield estimates of mean suspended-sediment load calculated by the flow-duration, rating-curve method that are more accurate and precise than those obtained for the non-linear model.
","language":"English","publisher":"Elsevier","doi":"10.1016/0022-1694(91)90057-O","issn":"00221694","usgsCitation":"Crawford, C.G., 1991, Estimation of suspended-sediment rating curves and mean suspended-sediment loads: Journal of Hydrology, v. 129, no. 1-4, p. 331-348, https://doi.org/10.1016/0022-1694(91)90057-O.","productDescription":"18 p.","startPage":"331","endPage":"348","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":346,"text":"Indiana Water Science Center","active":true,"usgs":true}],"links":[{"id":223633,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"129","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0bb2e4b0c8380cd5282e","contributors":{"authors":[{"text":"Crawford, Charles G. 0000-0003-1653-7841 cgcrawfo@usgs.gov","orcid":"https://orcid.org/0000-0003-1653-7841","contributorId":1064,"corporation":false,"usgs":true,"family":"Crawford","given":"Charles","email":"cgcrawfo@usgs.gov","middleInitial":"G.","affiliations":[{"id":37947,"text":"Upper Midwest Water Science Center","active":true,"usgs":true},{"id":451,"text":"National Water Quality Assessment Program","active":true,"usgs":true}],"preferred":true,"id":369872,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70015032,"text":"70015032 - 1991 - The effect of sample hydration on 13C CPMAS NMR spectra of fulvic acids","interactions":[],"lastModifiedDate":"2025-03-13T22:10:10.552631","indexId":"70015032","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2958,"text":"Organic Geochemistry","active":true,"publicationSubtype":{"id":10}},"title":"The effect of sample hydration on 13C CPMAS NMR spectra of fulvic acids","docAbstract":"Three fulvic acids, two of which have been well studied by a number of other groups (Armadale and Suwannee river fulvic acids) have been examined by high resolution solid-state 13C-NMR techniques to delineate the effect of absorbed water. Two main effects of absorbed water were observed: (1) changes in spin lattice relaxation times in the rotating frame and cross polarization times and (2) total loss of signal so that some fulvic acid is effectively in solution. These results suggest that discrepancies in the literature concerning observed relative signal intensities from different structural groups are due to absorbed water and emphasize the necessity for proper precautionary drying before spectroscopic analysis.
","language":"English","publisher":"Elsevier","doi":"10.1016/0146-6380(91)90092-X","usgsCitation":"Hatcher, P.G., and Wilson, M.A., 1991, The effect of sample hydration on 13C CPMAS NMR spectra of fulvic acids: Organic Geochemistry, v. 17, no. 3, p. 293-299, https://doi.org/10.1016/0146-6380(91)90092-X.","productDescription":"7 p.","startPage":"293","endPage":"299","costCenters":[],"links":[{"id":223797,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"17","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bab4be4b08c986b322d4a","contributors":{"authors":[{"text":"Hatcher, Patrick G.","contributorId":93625,"corporation":false,"usgs":true,"family":"Hatcher","given":"Patrick","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":369899,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wilson, Michael A.","contributorId":66335,"corporation":false,"usgs":true,"family":"Wilson","given":"Michael","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":369900,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70015033,"text":"70015033 - 1991 - Herbicides in surface waters of the midwestern United States: The effect of spring flush","interactions":[],"lastModifiedDate":"2019-03-28T07:18:50","indexId":"70015033","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1565,"text":"Environmental Science & Technology","onlineIssn":"1520-5851","printIssn":"0013-936X","active":true,"publicationSubtype":{"id":10}},"title":"Herbicides in surface waters of the midwestern United States: The effect of spring flush","docAbstract":"Approximately three-fourths of all preemergent herbicides used in the United States are applied to row crops over a 12-state area, called the \"corn belt\" (I). The application of these compounds may cause widespread degradation of water quality (2). Because herbicides are water soluble, there is the potential for leaching into groundwater and surface water (3, 4), as well as aerial transport and Occurrence in precipitation (5). Monitoring studies in the Midwest have shown widespread detection of herbicides in groundwater and in surface water (3,4); however, little is known about the regional impact of herbicide application (6). The objective of our research was to assess the mag. nitude and persistence of herbicide runoff in the spring flush at the regional scale.
","language":"English","publisher":"American Chemical Society","doi":"10.1021/es00022a018","issn":"0013936X","usgsCitation":"Thurman, E., Goolsby, D.A., Meyer, M.T., and Kolpin, D., 1991, Herbicides in surface waters of the midwestern United States: The effect of spring flush: Environmental Science & Technology, v. 25, no. 10, p. 1794-1796, https://doi.org/10.1021/es00022a018.","productDescription":"3 p.","startPage":"1794","endPage":"1796","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":351,"text":"Iowa Water Science Center","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":223798,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","geographicExtents":"{\"type\":\"FeatureCollection\",\"features\":[{\"type\":\"Feature\",\"geometry\":{\"type\":\"MultiPolygon\",\"coordinates\":[[[[-87.800477,42.49192],[-87.812461,42.232278],[-87.511043,41.696535],[-87.187651,41.629653],[-86.616978,41.896625],[-86.321803,42.310743],[-86.208309,42.762789],[-86.540916,43.633158],[-86.25395,44.64808],[-86.066745,44.905685],[-85.780439,44.977932],[-85.540497,45.210169],[-85.641652,44.810816],[-85.520205,44.960347],[-85.477423,44.813781],[-85.355478,45.282774],[-84.91585,45.393115],[-85.110884,45.526285],[-84.94565,45.708621],[-85.011433,45.757962],[-84.774156,45.788918],[-83.488826,45.355872],[-83.291346,45.062597],[-83.435822,45.000012],[-83.277213,44.7167],[-83.335248,44.357995],[-83.890145,43.934672],[-83.909479,43.672622],[-83.618602,43.628891],[-83.227093,43.981003],[-82.833103,44.036851],[-82.643166,43.852468],[-82.423086,42.988728],[-82.509935,42.637294],[-82.648776,42.550401],[-82.630922,42.64211],[-82.780817,42.652232],[-83.40822,41.832654],[-83.37573,41.686647],[-82.481214,41.381342],[-81.69325,41.514161],[-80.533774,41.973475],[-80.518991,40.638801],[-80.667957,40.582496],[-80.619297,40.26517],[-80.88036,39.620706],[-81.656138,39.277355],[-81.874857,38.881174],[-82.068864,38.984878],[-82.318111,38.457876],[-82.569368,38.406258],[-82.611343,38.171548],[-82.474635,37.905902],[-81.982479,37.541807],[-83.128813,36.757864],[-83.690714,36.582581],[-88.011792,36.677025],[-88.127378,36.49854],[-89.5391,36.498201],[-89.733095,36.000608],[-90.368718,35.995812],[-90.075934,36.281485],[-90.157136,36.484317],[-94.617919,36.499414],[-94.699735,36.998805],[-102.000447,36.993249],[-102.051614,41.002377],[-104.039238,41.001502],[-104.043814,45.868385],[-96.618295,45.935407],[-96.554507,46.083978],[-96.798823,46.658071],[-96.851293,47.589264],[-97.139497,48.153108],[-97.108655,48.691484],[-97.238387,48.982631],[-95.153711,48.998903],[-95.153314,49.384358],[-94.878454,49.333193],[-94.640803,48.741171],[-93.818375,48.534442],[-92.984963,48.623731],[-92.634931,48.542873],[-92.698824,48.494892],[-92.341207,48.23248],[-92.066269,48.359602],[-91.542512,48.053268],[-90.88548,48.245784],[-90.703702,48.096009],[-89.489226,48.014528],[-90.86827,47.5569],[-92.058888,46.809938],[-91.942988,46.679939],[-90.880358,46.957661],[-90.78804,46.844886],[-90.920813,46.637432],[-90.398478,46.575832],[-88.982483,46.99883],[-88.400224,47.379551],[-87.816958,47.471998],[-87.730804,47.449112],[-88.349952,47.076377],[-88.462349,46.786711],[-88.167373,46.9588],[-87.915943,46.909508],[-87.619747,46.79821],[-87.366767,46.507303],[-86.850111,46.434114],[-86.188024,46.654008],[-84.964652,46.772845],[-84.969464,46.47629],[-84.177428,46.52692],[-84.097766,46.256512],[-84.247687,46.17989],[-83.931175,46.017871],[-83.63498,46.103953],[-83.49484,45.999541],[-84.345451,45.946569],[-84.656567,46.052654],[-84.820557,45.868293],[-85.047028,46.020603],[-85.528403,46.087121],[-85.663966,45.967013],[-86.278007,45.942057],[-86.687208,45.634253],[-86.532989,45.882665],[-86.92106,45.697868],[-87.018902,45.838886],[-88.027103,44.578992],[-87.943801,44.529693],[-87.428144,44.890738],[-87.021088,45.296541],[-87.73063,43.893862],[-87.910172,43.236634],[-87.800477,42.49192]]],[[[-88.684434,48.115785],[-88.447236,48.182916],[-89.022736,47.858532],[-89.255202,47.876102],[-88.684434,48.115785]]],[[[-86.880572,45.331467],[-86.956192,45.351179],[-86.82177,45.427602],[-86.880572,45.331467]]]]},\"properties\":{\"name\":\"Iowa\",\"nation\":\"USA \"}}]}","volume":"25","issue":"10","noUsgsAuthors":false,"publicationDate":"2002-05-01","publicationStatus":"PW","scienceBaseUri":"505a3070e4b0c8380cd5d64c","contributors":{"authors":[{"text":"Thurman, E.M.","contributorId":102864,"corporation":false,"usgs":true,"family":"Thurman","given":"E.M.","affiliations":[],"preferred":false,"id":369904,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Goolsby, D. A.","contributorId":50508,"corporation":false,"usgs":true,"family":"Goolsby","given":"D.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":369901,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Meyer, M. T.","contributorId":92279,"corporation":false,"usgs":true,"family":"Meyer","given":"M.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":369903,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Kolpin, D.W.","contributorId":87565,"corporation":false,"usgs":true,"family":"Kolpin","given":"D.W.","email":"","affiliations":[],"preferred":false,"id":369902,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70015046,"text":"70015046 - 1991 - Flexural extension of the upper continental crust in collisional foredeeps","interactions":[],"lastModifiedDate":"2023-12-27T11:50:21.761856","indexId":"70015046","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","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":"Flexural extension of the upper continental crust in collisional foredeeps","docAbstract":"Normal faults on the outer slopes of trenches and collisional foredeeps reveal that high-amplitude lithospheric flexure can result in inelastic extensional deformation of the convex side of a flexed plate. This process, which we call \"flexural extension,\" differs fundamentally from rifting in that the lower lithosphere contracts while the upper lithosphere extends. In the Taconic foreland of New York, a >100-km-wide zone of brittle failure propagated ahead of the convergent plate boundary, rupturing the upper crust to an estimated depth of 15-20 km. Dip-slip displacement on normal faults in the Taconic and Arkoma foredeeps produced water depths like those in the closest modern analogue, the Timor Trough. Structural evidence does not support common illustrations of flexural normal faults as planar-irrotational structures which simply die out at shallow crustal depths. Instead, the surface geology shows that flexural normal faulting must be rotational with respect to the enveloping surface of the flexed plate. This toppled domino geometry implies the presence at depth of a detachment or zone of distributed ductile simple shear where fault displacement and block rotation are accommodated.
The delta 18 O values of gold-bearing quartz from the Juneau gold belt range from 15.2 to 20.8 per mil, indicating that ore fluid values ranged from 7.2 to 12.8 per mil at an estimated temperature of 300 degrees C. Hydrothermal micas from many of the deposits are characterized by delta D values of -75 to -53 per mil, and ore fluids were calculated to have values of -35 to -15 per mil. In contrast, extracted fluid inclusion waters have a broad range of delta D values, from -48 in relatively undeformed quartz to about -110 per mil for some of the more deformed quartz veins. This range of more than 60 per mil reflects various mixtures from inclusions containing isotopically heavy, primary ore fluids and those containing low-temperature, isotopically light meteoric waters that were trapped in late fractures during uplift of the veins to shallow crustal levels. These results indicate a deep crustal source for the ore fluids, most likely of metamorphic origin. Values of delta D for muscovite, biotite, and hornblende from country rocks, as well as of delta 18 O for quartz-feldspar and quartz-plagioclase, provide little evidence of deep circulation of meteoric water along the length of the gold belt.The provinciality of delta 34 data suggests a regional metamorphic fluid of approximately -6 per mil that acquired much of its sulfur from lithologies near sites of ore deposition. Sulfur ratios of sulfide minerals from auriferous quartz range from -17.8 to -5.6 per mil in black phyllite hosts, from -6.0 to -1.3 per mil in less reduced metasedimentary rocks, and from -3.8 to +1.2 per mil in relatively oxidized igneous rocks. The regional fluid is interpreted to have driven desulfidation reactions in relatively 34 S-depleted sulfur reservoirs in the phyllites and 34 S-enriched reservoirs in the more oxidized lithologies.
","language":"English","publisher":"Society of Economic Geologists","doi":"10.2113/gsecongeo.86.1.66","issn":"03610128","usgsCitation":"Goldfarb, R., Newberry, R., Pickthorn, W., and Gent, C.A., 1991, Oxygen, hydrogen, and sulfur isotope studies in the Juneau gold belt, southeastern Alaska: Constraints on the origin of hydrothermal fluids: Economic Geology, v. 86, no. 1, p. 66-80, https://doi.org/10.2113/gsecongeo.86.1.66.","productDescription":"15 p.","startPage":"66","endPage":"80","numberOfPages":"15","costCenters":[],"links":[{"id":224016,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"86","issue":"1","noUsgsAuthors":false,"publicationDate":"1991-02-01","publicationStatus":"PW","scienceBaseUri":"505a72bce4b0c8380cd76c88","contributors":{"authors":[{"text":"Goldfarb, R.J.","contributorId":38143,"corporation":false,"usgs":true,"family":"Goldfarb","given":"R.J.","email":"","affiliations":[],"preferred":false,"id":369941,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Newberry, R.J.","contributorId":50558,"corporation":false,"usgs":true,"family":"Newberry","given":"R.J.","email":"","affiliations":[],"preferred":false,"id":369942,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Pickthorn, W.J.","contributorId":95458,"corporation":false,"usgs":true,"family":"Pickthorn","given":"W.J.","email":"","affiliations":[],"preferred":false,"id":369943,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Gent, C. A.","contributorId":17955,"corporation":false,"usgs":true,"family":"Gent","given":"C.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":369940,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70015065,"text":"70015065 - 1991 - Petrogenesis and geological history of a uranium source rock: a case study in northeastern Washington, U.S.A.","interactions":[],"lastModifiedDate":"2023-02-21T13:09:28.91328","indexId":"70015065","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":835,"text":"Applied Geochemistry","active":true,"publicationSubtype":{"id":10}},"title":"Petrogenesis and geological history of a uranium source rock: a case study in northeastern Washington, U.S.A.","docAbstract":"A small (4 km2) drainage basin in northeastern Washington contains highly uraniferous groundwater and highly uraniferous peaty sediments of Holocene age. The U is derived from granitic bedrock that underlies the entire drainage basin and that contains 9–16 ppm U. This local bedrock was studied by petrographic, chemical and isotopic methods to determine conditions of its petrogenesis and post-emplacement history that may have contributed to its present high U content and source-rock capability. The original magma was derived by anatexis of Precambrian continental crust of probable mixed metaigneous and metasedimentary character. Mineral-melt partitioning controlled the enrichment of U in chemically evolved phases of the crystallizing melt. Following emplacement in the upper crust at ∼100Ma, the pluton interacted with meteoric-hydrothermal water at ambient temperatures 300°C. Locally intense fracturing promoted alteration, and fracturing and alteration probably continued during later regional uplift in the Eocene. Regional uplift was followed by low-temperature alteration and weathering in the middle to late Tertiary. The combined result of hydrothermal alteration and low-temperature alteration and weathering was the redistribution of U from primary mineral hosts such as allanite to new sites on fracture surfaces and in secondary minerals such as hematite. Zones of highly fractured and altered rock show the most obvious evidence of this process. A model is proposed in which high-angle fractures beneath the drainage basin were the sites of Tertiary supergene enrichments of U. Recent glacio-isostatic uplift has elevated these older enriched zones to shallow levels where they are now being leached by oxidizing groundwater. The chemistry, mineralogy, texture and geological history of this U source-rock suggest criteria for locating other granitic terrane that may contain uraniferous waters and associated young surficial U deposits. The details of U distribution and mobility at this site also apply to the general topic of U mobility in granitic rocks.
\\A filtration model commonly used to describe removal of colloids during packed-bed filtration in water treatment applications was modified for describing downgradient transport of bacteria in sandy, aquifer sediments. The modified model was applied to the results of a small-scale (7 m), natural-gradient tracer test and to observations of an indigenous bacterial population moving downgradient within a plume of organically contaminated groundwater in Cape Cod, MA. The model reasonably accounted for concentration histories of labeled bacteria appearing at samplers downgradient from the injection well in the tracer experiment and for the observed 0.25-μm increase in average cell length for an unlabeled, indigenous bacterial population, 0.6 km downgradient from the source of the plume. Several uncertainties were apparent in applying filtration theory to problems involving transport of bacteria in groundwater. However, adsorption (attachment) appeared to be a major control of the extent of bacterial movement downgradient, which could be described, in part, by filtration theory. Estimates of the collision efficiency factor, which represents the physicochemical factors that determine adsorption of the bacteria onto the grain surfaces, ranged from 5.4 x 10-3 to 9.7 x 10-3.
","language":"English","publisher":"ACS","doi":"10.1021/es00013a021","issn":"0013936X","usgsCitation":"Harvey, R., and Garabedian, S., 1991, Use of colloid filtration theory in modeling movement of bacteria through a contaminated sandy aquifer: Environmental Science & Technology, v. 25, no. 1, p. 178-185, https://doi.org/10.1021/es00013a021.","productDescription":"8 p.","startPage":"178","endPage":"185","numberOfPages":"8","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":224234,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"25","issue":"1","noUsgsAuthors":false,"publicationDate":"2002-05-01","publicationStatus":"PW","scienceBaseUri":"505bbed7e4b08c986b3297f6","contributors":{"authors":[{"text":"Harvey, R.W. 0000-0002-2791-8503","orcid":"https://orcid.org/0000-0002-2791-8503","contributorId":11757,"corporation":false,"usgs":true,"family":"Harvey","given":"R.W.","affiliations":[],"preferred":false,"id":369976,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Garabedian, S. P.","contributorId":56657,"corporation":false,"usgs":true,"family":"Garabedian","given":"S. P.","affiliations":[],"preferred":false,"id":369977,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70015076,"text":"70015076 - 1991 - Importance of hydrologic data for interpreting wetland maps and assessing wetland loss and mitigation","interactions":[],"lastModifiedDate":"2012-03-12T17:18:59","indexId":"70015076","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1022,"text":"Biological Report - US Fish & Wildlife Service","active":true,"publicationSubtype":{"id":10}},"title":"Importance of hydrologic data for interpreting wetland maps and assessing wetland loss and mitigation","docAbstract":"The US Geological Survey collects and disseminates, in written and digital formats, groundwater and surface-water information related to the tidal and nontidal wetlands of the United States. This information includes quantity, quality, and availability of groundwater and surface water; groundwater and surface-water interactions (recharge-discharge); groundwater flow; and the basic surface-water characteristics of streams, rivers, lakes, and wetlands. Water resources information in digital format can be used in geographic information systems (GISs) for many purposes related to wetlands. US Geological Survey wetland-related activities include collection of information important for assessing and mitigating coastal wetland loss and modification, hydrologic data collection and interpretation, GIS activities, identification of national trends in water quality and quantity, and process-oriented wetland research. -Author","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Biological Report - US Fish & Wildlife Service","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","usgsCitation":"Carter, V., 1991, Importance of hydrologic data for interpreting wetland maps and assessing wetland loss and mitigation: Biological Report - US Fish & Wildlife Service, v. 90, no. 18, p. 79-85.","startPage":"79","endPage":"85","numberOfPages":"7","costCenters":[],"links":[{"id":224403,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"90","issue":"18","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a393be4b0c8380cd61856","contributors":{"authors":[{"text":"Carter, V.","contributorId":61115,"corporation":false,"usgs":true,"family":"Carter","given":"V.","email":"","affiliations":[],"preferred":false,"id":369998,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70015077,"text":"70015077 - 1991 - Louisiana coastal GIS network: Graphical user interface for access to spatial data","interactions":[],"lastModifiedDate":"2017-09-06T14:48:50","indexId":"70015077","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Louisiana coastal GIS network: Graphical user interface for access to spatial data","docAbstract":"Louisiana's coastal wetlands support a large percentage of the nation's seafood and fur industries, vast deposits of oil and natural gas, habitat for thousands of species of plants and animals, winter nesting grounds and migratory paths for numerous waterfowl, and many recreational resources enjoyed by residents and tourists. Louisiana's wetlands also have the highest rates of coastal erosion and wetland loss in the nation. While numerous studies across many disciplines have been conducted on both local and regional scales, no complete inventory exists for this information. The Louisiana Coastal Geographic Information System Network (LCGISN) is currently being developed to facilitate access to existing data for coastal zone planners, managers, and researchers. The Louisiana Geological Survey (LGS), in cooperation with the LSU Department of Geography and Anthropology, the Computer Aided Design and Geographic Information Systems Research Laboratory (CADGIS), and others, is pursuing this project under the terms of a cooperative agreement with the U.S. Geological Survey. LCGISN is an automated system for searching and retrieving geographic, cartographic, and bibliographic data. By linking original programming with an existing GIS software package and an industry standard relational database management system, LCGISN will provide the capability for users to search for data references by interactively defining the area of interest on a displayed map/image reference background. Several agencies will be networked to provide easy access to a wide variety of information. LCGISN, with its headquarters at LGS, will serve as the central node on the network, providing data format conversions, projection and datum transformations, and storage of several of the most commonly used data sets. Thematic mapper data, USGS 7.5-minute quadrangle map boundaries, political and legal boundaries, major transportation routes, and other digital data will provide a base map to aid the user in selecting the exact area of interest. Then, the user will set search criteria by proceeding through a series of menu-driven options. The system will then return any or all of the following: a list of digital maps or imagery that can be displayed immediately and visually overlayed, a list of maps/remotely sensed data and information on their availability, and a list of bibliographic references concerning the area and subject defined.","largerWorkTitle":"GIS/LIS 1991 Proceedings","conferenceTitle":"Proceedings of GIS/LIS '91","conferenceDate":"28 October 1991 through 1 November 1991","conferenceLocation":"Atlanta, GA, USA","language":"English","publisher":"Publ by ASPRS","publisherLocation":"Bethesda, MD, United States","isbn":"0944426751","usgsCitation":"Hiland, M., McBride, R., Davis, D., Braud, D., Streiffer, H., Jones, F., Lewis, A., and Williams, S., 1991, Louisiana coastal GIS network: Graphical user interface for access to spatial data, in GIS/LIS 1991 Proceedings, v. 2, Atlanta, GA, USA, 28 October 1991 through 1 November 1991, p. 845-856.","productDescription":"12 p.","startPage":"845","endPage":"856","costCenters":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"links":[{"id":223579,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -91.4501953125,\n 29.03215782622282\n ],\n [\n -88.39599609375,\n 29.03215782622282\n ],\n [\n -88.39599609375,\n 30.453409130203596\n ],\n [\n -91.4501953125,\n 30.453409130203596\n ],\n [\n -91.4501953125,\n 29.03215782622282\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a49ece4b0c8380cd689ba","contributors":{"authors":[{"text":"Hiland, Matteson","contributorId":101390,"corporation":false,"usgs":true,"family":"Hiland","given":"Matteson","email":"","affiliations":[],"preferred":false,"id":370004,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McBride, Randolph A.","contributorId":48711,"corporation":false,"usgs":false,"family":"McBride","given":"Randolph A.","affiliations":[{"id":5115,"text":"Louisiana State University","active":true,"usgs":false}],"preferred":false,"id":370000,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Davis, Donald","contributorId":90471,"corporation":false,"usgs":true,"family":"Davis","given":"Donald","affiliations":[],"preferred":false,"id":370003,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Braud, Dewitt","contributorId":66853,"corporation":false,"usgs":true,"family":"Braud","given":"Dewitt","affiliations":[],"preferred":false,"id":370001,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Streiffer, Henry","contributorId":105057,"corporation":false,"usgs":true,"family":"Streiffer","given":"Henry","email":"","affiliations":[],"preferred":false,"id":370005,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Jones, Farrell","contributorId":105860,"corporation":false,"usgs":true,"family":"Jones","given":"Farrell","affiliations":[],"preferred":false,"id":370006,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Lewis, Anthony","contributorId":67221,"corporation":false,"usgs":true,"family":"Lewis","given":"Anthony","affiliations":[],"preferred":false,"id":370002,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Williams, S.","contributorId":18514,"corporation":false,"usgs":true,"family":"Williams","given":"S.","email":"","affiliations":[],"preferred":false,"id":369999,"contributorType":{"id":1,"text":"Authors"},"rank":8}]}} ,{"id":70015103,"text":"70015103 - 1991 - Estimating estuarine flushing and residence times in Charlotte Harbor, Florida, via salt balance and a box model","interactions":[],"lastModifiedDate":"2013-02-22T13:39:15","indexId":"70015103","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2620,"text":"Limnology and Oceanography","active":true,"publicationSubtype":{"id":10}},"title":"Estimating estuarine flushing and residence times in Charlotte Harbor, Florida, via salt balance and a box model","docAbstract":"The new concept is that, over many tidal cycles, the tidally averaged \"flow' (Qg) of water from the Gulf of Mexico, with a salinity of 35???, can be treated as a constant at any point in the estuary. This flow is used in a simple mixing equation to predict salinity in the estuary at different river inflows, and the predicted salinities are used to compute residence times for water in the estuary. The techniques developed to achieve optimal precision in the relation between river inflow and salinity include a newly derived equation to fit Qg by a least-squares method and a procedure to determine the optimal averaging period for river inflow. Results from Charlotte Harbor indicate that, under average (70 m3s-1) river inflow, 95% of the original water present in the harbor flushes into the gulf in 130 d. -from Authors","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Limnology and Oceanography","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"American Society of Limnology and Oceanography","usgsCitation":"Miller, R.L., and McPherson, B.F., 1991, Estimating estuarine flushing and residence times in Charlotte Harbor, Florida, via salt balance and a box model: Limnology and Oceanography, v. 36, no. 3, p. 602-612.","startPage":"602","endPage":"612","numberOfPages":"11","costCenters":[],"links":[{"id":223968,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":267941,"type":{"id":11,"text":"Document"},"url":"https://www.aslo.org/lo/toc/vol_36/issue_3/0602.pdf"}],"volume":"36","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0b1ae4b0c8380cd52588","contributors":{"authors":[{"text":"Miller, R. L.","contributorId":54178,"corporation":false,"usgs":true,"family":"Miller","given":"R.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":370078,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McPherson, B. F.","contributorId":62983,"corporation":false,"usgs":true,"family":"McPherson","given":"B.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":370079,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70015104,"text":"70015104 - 1991 - Aquatic fulvic acids in microbially based ecosystems: results from two desert lakes in Antarctica","interactions":[],"lastModifiedDate":"2013-02-22T14:12:27","indexId":"70015104","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2620,"text":"Limnology and Oceanography","active":true,"publicationSubtype":{"id":10}},"title":"Aquatic fulvic acids in microbially based ecosystems: results from two desert lakes in Antarctica","docAbstract":"These lakes receive very limited input of organic material from the surrounding barren desert, but they sustain algal and bacterial populations under permanent ice cover. One lake has an extensive anoxic zone and high salinities; the other is oxic and has low salinities. Despite these differences, fulvic acids from both lakes had similar elemental compositions, carbon distributions, and amino acid contents, indicating that the chemistry of microbially derived fulvic acvids is not strongly influenced by chemical conditions in the water column. Compared to fulvic acids from other natural waters, these fulvic acids have low C:N atomic ratios (19-25) and low contents of aromatic carbons (5-7% of total carbon atoms); they are most similar to marine fulvic acids. -from Authors","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Limnology and Oceanography","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"American Society of Limnology and Oceanography","usgsCitation":"McKnight, D.M., Aiken, G., and Smith, R.L., 1991, Aquatic fulvic acids in microbially based ecosystems: results from two desert lakes in Antarctica: Limnology and Oceanography, v. 36, no. 5, p. 998-1006.","startPage":"998","endPage":"1006","numberOfPages":"9","costCenters":[],"links":[{"id":224017,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":267942,"type":{"id":11,"text":"Document"},"url":"https://www.aslo.org/lo/toc/vol_36/issue_5/0998.pdf"}],"volume":"36","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ed0de4b0c8380cd495c4","contributors":{"authors":[{"text":"McKnight, Diane M.","contributorId":59773,"corporation":false,"usgs":false,"family":"McKnight","given":"Diane","email":"","middleInitial":"M.","affiliations":[{"id":16833,"text":"INSTAAR, University of Colorado","active":true,"usgs":false}],"preferred":false,"id":370081,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Aiken, G. R. 0000-0001-8454-0984","orcid":"https://orcid.org/0000-0001-8454-0984","contributorId":14452,"corporation":false,"usgs":true,"family":"Aiken","given":"G. R.","affiliations":[],"preferred":false,"id":370080,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Smith, R. L.","contributorId":93904,"corporation":false,"usgs":true,"family":"Smith","given":"R.","email":"","middleInitial":"L.","affiliations":[{"id":595,"text":"U.S. Geological Survey","active":false,"usgs":true}],"preferred":false,"id":370082,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70015145,"text":"70015145 - 1991 - New evidence on the hydrothermal system in Long Valley caldera, California, from wells, fluid sampling, electrical geophysics, and age determinations of hot-spring deposits","interactions":[],"lastModifiedDate":"2012-03-12T17:18:55","indexId":"70015145","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2499,"text":"Journal of Volcanology and Geothermal Research","active":true,"publicationSubtype":{"id":10}},"title":"New evidence on the hydrothermal system in Long Valley caldera, California, from wells, fluid sampling, electrical geophysics, and age determinations of hot-spring deposits","docAbstract":"Data collected since 1985 from test drilling, fluid sampling, and geologic and geophysical investigations provide a clearer definition of the hydrothermal system in Long Valley caldera than was previously available. This information confirms the existence of high-temperature (> 200??C) reservoirs within the volcanic fill in parts of the west moat. These reservoirs contain fluids which are chemically similar to thermal fluids encountered in the central and eastern parts of the caldera. The roots of the present-day hydrothermal system (the source reservoir, principal zones of upflow, and the magmatic heat source) most likely occur within metamorphic basement rocks beneath the western part of the caldera. Geothermometer-temperature estimates for the source reservoir range from 214 to 248??C. Zones of upflow of hot water could exist beneath the plateau of moat rhyolite located west of the resurgent dome or beneath Mammoth Mountain. Lateral flow of thermal water away from such upflow zones through reservoirs in the Bishop Tuff and early rhyolite accounts for temperature reversals encountered in most existing wells. Dating of hot-spring deposits from active and inactive thermal areas confirms previous interpretations of the evolution of hydrothermal activity that suggest two periods of extensive hot-spring discharge, one peaking about 300 ka and another extending from about 40 ka to the present. The onset of hydrothermal activity around 40 ka coincides with the initiation of rhyolitic volcanism along the Mono-Inyo Craters volcanic chain that extends beneath the caldera's west moat. ?? 1991.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Volcanology and Geothermal Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"03770273","usgsCitation":"Sorey, M., Suemnicht, G., Sturchio, N., and Nordquist, G., 1991, New evidence on the hydrothermal system in Long Valley caldera, California, from wells, fluid sampling, electrical geophysics, and age determinations of hot-spring deposits: Journal of Volcanology and Geothermal Research, v. 48, no. 3-4, p. 229-263.","startPage":"229","endPage":"263","numberOfPages":"35","costCenters":[],"links":[{"id":223750,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"48","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a657de4b0c8380cd72be9","contributors":{"authors":[{"text":"Sorey, M.L.","contributorId":73185,"corporation":false,"usgs":true,"family":"Sorey","given":"M.L.","affiliations":[],"preferred":false,"id":370198,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Suemnicht, G.A.","contributorId":11339,"corporation":false,"usgs":true,"family":"Suemnicht","given":"G.A.","email":"","affiliations":[],"preferred":false,"id":370196,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Sturchio, N.C.","contributorId":16580,"corporation":false,"usgs":true,"family":"Sturchio","given":"N.C.","affiliations":[],"preferred":false,"id":370197,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Nordquist, G.A.","contributorId":86493,"corporation":false,"usgs":true,"family":"Nordquist","given":"G.A.","email":"","affiliations":[],"preferred":false,"id":370199,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70015162,"text":"70015162 - 1991 - Observations of gas hydrates in marine sediments, offshore northern California","interactions":[],"lastModifiedDate":"2024-09-23T11:55:33.686226","indexId":"70015162","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","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":"Observations of gas hydrates in marine sediments, offshore northern California","docAbstract":"Biogenic gas hydrates were recovered in shallow cores (< 6 m deep) from the Eel River basin in offshore northern California between 40°38′ and 40°56′N. The gas hydrates contained primarily methane (δ13C = −57.6 to −69.1‰) and occurred as dispersed crystals, small (2–20 mm) nodules, and layered bands within the sediment. These hydrates, recovered in sediment at water depths between 510 and 642 m, coincide nearly, but not exactly, with areas showing bottom-simulating reflectors (BSRs) on seismic-reflection records. This study confirms indirect geophysical and geologic observations that gas hydrates are present north of the Mendocino Fracture Zone in sediment of the Eel River basin but probably are absent to the south in the Point Arena basin. This discovery extends the confirmed sites of gas hydrates in the eastern Pacific region beyond the Peruvian and Central American margins to the northern California margin.
No abstract available.
","language":"English","publisher":"American Chemical Society","doi":"10.1021/es00016a008","issn":"0013936X","usgsCitation":"Chiou, C.T., Kile, D.E., and Rutherford, D., 1991, The neutral oil in commercial linear alkylbenzenesulfonate and its effect on organic solute solubility in water: Environmental Science & Technology, v. 25, no. 4, p. 660-665, https://doi.org/10.1021/es00016a008.","productDescription":"6 p.","startPage":"660","endPage":"665","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":223107,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"25","issue":"4","noUsgsAuthors":false,"publicationDate":"2002-05-01","publicationStatus":"PW","scienceBaseUri":"505bae10e4b08c986b323ee7","contributors":{"authors":[{"text":"Chiou, C. T.","contributorId":97080,"corporation":false,"usgs":true,"family":"Chiou","given":"C.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":373231,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kile, D. E.","contributorId":22758,"corporation":false,"usgs":true,"family":"Kile","given":"D.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":373230,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Rutherford, D.W.","contributorId":21244,"corporation":false,"usgs":true,"family":"Rutherford","given":"D.W.","email":"","affiliations":[],"preferred":false,"id":373229,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70016344,"text":"70016344 - 1991 - Late Neogene marine Ostracoda from Tjornes, Iceland","interactions":[],"lastModifiedDate":"2024-06-19T00:06:23.391777","indexId":"70016344","displayToPublicDate":"1991-01-01T00:00:00","publicationYear":"1991","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2412,"text":"Journal of Paleontology","active":true,"publicationSubtype":{"id":10}},"title":"Late Neogene marine Ostracoda from Tjornes, Iceland","docAbstract":"On the western side of the Tjörnes Peninsula in northern Iceland exposures of fossiliferous marine sediments, basalts, and glacial tills record the climatic history of this region of the North Atlantic Ocean. Seventy-five marine ostracode species were recovered from the Pliocene Tjörnes sediments and Quaternary sediments known as the Breidavik beds. The ostracode assemblages contain many warm-water genera that do not inhabit Iceland today and indicate early to middle Pliocene (4.5–3.0 Ma) winter and summer bottom-water temperatures that averaged 5–6°C and 14–16°C, respectively (maximum 20°C in summer, rarely below 3°C in winter except during a brief cooling 3.5–3.2 Ma). An intensified North Atlantic Drift and a diminished or absent East Greenland Current account for warm-water oceanographic conditions at 66°N. Late Pliocene marine climates were cooler with winter and summer averages of about 9°C and 8°C. Early Pleistocene ostracode assemblages dated at 1.7–1.3 Ma contain extant arctic–subarctic species that indicate winter and summer temperatures of about − 1.5°C and 4–5°C. New species Bensonocythere eirikssoni, Robertsonites williamsi, Hemicythere rekaensis, Thaerocythere mayburyae, Thaerocythere whatleyi, Leptocythere tjornesensis, Tetracytherura bardarsoni, and Cytheromorpha einarssoni are described.
A deeply incised gorge is buried nearly 800 m beneath the floor of the Valencia Trough in the western Mediterranean Sea. The gorge is steeply cut more than 200m into Messinian evaporite deposits and has been mapped for more than 40 km. Published and unpublished seismic profiles show the total length to be nearly 300 km. The gorge is not aligned with any known large fluvial systems, and its orientation indicates that it may have been connected near Valencia with the Betic Strait, the portal in southern Spain proposed to link the Atlantic and the western Mediterranean. The Betic Strait was probably open at least through early Messinian time. Conservative estimates show that sea water flowing through the Valencia gorge at rates of 0.5 to 2 m/s could have refilled the western Mediterranean basins below 2000 m in less than 50 yr.