A spectacular submarine spring is located about 4 km east of Crescent Beach, FL, in the Atlantic Ocean. The single vent feature of Crescent Beach Spring provides a unique opportunity to examine onshore–offshore hydrogeologic processes, as well as point source submarine ground water discharge. The Floridan aquifer system in northeastern Florida consists of Tertiary interspersed limestone and dolomite strata. Impermeable beds confine the water-bearing zones under artesian pressure. Miocene and younger confining strata have been eroded away at the vent feature, enabling direct hydrologic communication of Eocene ground water with coastal bottom waters.
The spring water had a salinity of 6.02, which was immediately diluted by ambient seawater during advection/mixing. The concentration of major solutes in spring water and onshore well waters confirm a generalized easterly flow direction of artesian ground water. Nutrient concentrations were generally low in the reducing vent samples, and the majority of the total nitrogen species existed as NH3. The submarine ground water tracers, Rn-222 (1174 dpm l−1, dpm), methane (232 nM) and barium (294.5 nM) were all highly enriched in the spring water relative to ambient seawater. The concentrations of the reverse redox elements U, V and Mo were expectedly low in the submarine waters. The strontium isotope ratio of the vent water (87Sr/86Sr=0.70798) suggests that the spring water contain an integrated signature indicative of Floridan aquifer system ground water. Additional Sr isotopic ratios from a series of surficial and Lower Floridan well samples suggest dynamic ground water mixing, and do not provide clear evidence for a single hydrogeologic water source at the spring vent. In this karst-dominated aquifer, such energetic mixing at the vent feature is expected, and would be facilitated by conduit and fractured flow. Radium isotope activities were utilized to estimate flow-path trajectories and to provide information on potential travel times between an onshore well and the spring. Using either 223Ra and 224Ra or 228Ra, and qualifying this approach with several key assumptions, estimates of water mass travel times from an upper Floridan well in Crescent Beach to the submarine vent feature (distance=4050 m) are in the order of ∼0.01–0.1 m min−1.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0009-2541(01)00322-9","issn":"00092541","usgsCitation":"Swarzenski, P., Reich, C., Spechler, R., Kindinger, J., and Moore, W., 2001, Using multiple geochemical tracers to characterize the hydrogeology of the submarine spring off Crescent Beach, Florida: Chemical Geology, v. 179, no. 1-4, p. 187-202, https://doi.org/10.1016/S0009-2541(01)00322-9.","productDescription":"16 p.","startPage":"187","endPage":"202","numberOfPages":"16","costCenters":[],"links":[{"id":232585,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Florida","otherGeospatial":"Crescent Beach","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -81.28028869628905,\n 29.74798440371394\n ],\n [\n -81.23153686523438,\n 29.74798440371394\n ],\n [\n -81.23153686523438,\n 29.786429141465277\n ],\n [\n -81.28028869628905,\n 29.786429141465277\n ],\n [\n -81.28028869628905,\n 29.74798440371394\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"179","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bc07be4b08c986b32a152","contributors":{"authors":[{"text":"Swarzenski, P.W. 0000-0003-0116-0578","orcid":"https://orcid.org/0000-0003-0116-0578","contributorId":29487,"corporation":false,"usgs":true,"family":"Swarzenski","given":"P.W.","affiliations":[],"preferred":false,"id":398826,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Reich, C. D. 0000-0002-2534-1456","orcid":"https://orcid.org/0000-0002-2534-1456","contributorId":36978,"corporation":false,"usgs":true,"family":"Reich","given":"C. D.","affiliations":[],"preferred":false,"id":398827,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Spechler, R. M.","contributorId":85961,"corporation":false,"usgs":true,"family":"Spechler","given":"R. M.","affiliations":[],"preferred":false,"id":398829,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Kindinger, J. L.","contributorId":38983,"corporation":false,"usgs":true,"family":"Kindinger","given":"J. L.","affiliations":[],"preferred":false,"id":398828,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Moore, W.S.","contributorId":90875,"corporation":false,"usgs":true,"family":"Moore","given":"W.S.","email":"","affiliations":[],"preferred":false,"id":398830,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70023730,"text":"70023730 - 2001 - A method for mapping apparent stress and energy radiation applied to the 1994 Northridge earthquake fault zone-revisited","interactions":[],"lastModifiedDate":"2012-03-12T17:20:13","indexId":"70023730","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1807,"text":"Geophysical Research Letters","active":true,"publicationSubtype":{"id":10}},"title":"A method for mapping apparent stress and energy radiation applied to the 1994 Northridge earthquake fault zone-revisited","docAbstract":"McGarr and Fletcher (2000) introduced a technique for estimating apparent stress and seismic energy radiation associated with small patches of a larger fault plane and then applied this method to the slip model of the Northridge earthquake (Wald et al., 1996). These results must be revised because we did not take account of the difference between the seismic energy near the fault and that in the farfield. The fraction f(VR) of the near-field energy that propagates into the far-field is a monotonic function that ranges from 0.11 to 0.40 as rupture velocity VR increases from 0.6?? to 0.95??, where ?? is the shear wave speed. The revised equation for apparent stress for subfault ij is taij = f(VR) ????/ 2 Dij??? D(t)ij2dt, where ?? is density, D(t)ij is the time-dependent slip, and Dij is the final slip. The corresponding seismic energy is Eaij = ADijtaij, where A is the subfault area. Our corrected distributions of apparent stress and radiated energy over the Northridge earthquake fault zone are about 35% of those published before.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Geophysical Research Letters","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1029/2001GL013094","issn":"00948276","usgsCitation":"McGarr, A., and Fletcher, J.B., 2001, A method for mapping apparent stress and energy radiation applied to the 1994 Northridge earthquake fault zone-revisited: Geophysical Research Letters, v. 28, no. 18, p. 3529-3532, https://doi.org/10.1029/2001GL013094.","startPage":"3529","endPage":"3532","numberOfPages":"4","costCenters":[],"links":[{"id":489796,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2001gl013094","text":"Publisher Index Page"},{"id":232384,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":207436,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1029/2001GL013094"}],"volume":"28","issue":"18","noUsgsAuthors":false,"publicationDate":"2001-09-15","publicationStatus":"PW","scienceBaseUri":"5059e454e4b0c8380cd465b1","contributors":{"authors":[{"text":"McGarr, Art 0000-0001-9769-4093","orcid":"https://orcid.org/0000-0001-9769-4093","contributorId":43491,"corporation":false,"usgs":true,"family":"McGarr","given":"Art","affiliations":[],"preferred":false,"id":398619,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Fletcher, Joe B.","contributorId":8850,"corporation":false,"usgs":true,"family":"Fletcher","given":"Joe","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":398618,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70023589,"text":"70023589 - 2001 - Molecular resolution and fragmentation of fulvic acid by electrospray ionization/multistage tandem mass spectrometry","interactions":[],"lastModifiedDate":"2018-12-03T08:05:21","indexId":"70023589","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":761,"text":"Analytical Chemistry","active":true,"publicationSubtype":{"id":10}},"title":"Molecular resolution and fragmentation of fulvic acid by electrospray ionization/multistage tandem mass spectrometry","docAbstract":"Molecular weight distributions of fulvic acid from the Suwannee River, Georgia, were investigated by electrospray ionization/quadrupole mass spectrometry (ESI/QMS), and fragmentation pathways of specific fulvic acid masses were investigated by electrospray ionization/ion trap multistage tandem mass spectrometry (ESI/MST/MS). ESI/QMS studies of the free acid form of low molecular weight poly(carboxylic acid) standards in 75% methanol/25% water mobile phase found that negative ion detection gave the optimum generation of parent ions that can be used for molecular weight determinations. However, experiments with poly(acrylic acid) mixtures and specific high molecular weight standards found multiply charged negative ions that gave a low bias to molecular mass distributions. The number of negative charges on a molecule is dependent on the distance between charges. ESI/MST/MS of model compounds found characteristic water loss from alcohol dehydration and anhydride formation, as well as CO2 loss from decarboxylation, and CO loss from ester structures. Application of these fragmentation pathways to specific masses of fulvic acid isolated and fragmented by ESI/MST/MS is indicative of specific structures that can serve as a basis for future structural confirmation after these hypothesized structures are synthesized.","language":"English","publisher":"ACS","doi":"10.1021/ac0012593","issn":"00032700","usgsCitation":"Leenheer, J., Rostad, C., Gates, P.M., Furlong, E., and Ferrer, I., 2001, Molecular resolution and fragmentation of fulvic acid by electrospray ionization/multistage tandem mass spectrometry: Analytical Chemistry, v. 73, no. 7, p. 1461-1471, https://doi.org/10.1021/ac0012593.","productDescription":"11 p.","startPage":"1461","endPage":"1471","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":232657,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":207588,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1021/ac0012593"}],"volume":"73","issue":"7","noUsgsAuthors":false,"publicationDate":"2001-03-07","publicationStatus":"PW","scienceBaseUri":"505a5d10e4b0c8380cd7012d","contributors":{"authors":[{"text":"Leenheer, J.A.","contributorId":75123,"corporation":false,"usgs":true,"family":"Leenheer","given":"J.A.","affiliations":[],"preferred":false,"id":398146,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Rostad, C.E.","contributorId":50939,"corporation":false,"usgs":true,"family":"Rostad","given":"C.E.","email":"","affiliations":[],"preferred":false,"id":398145,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Gates, Paul M.","contributorId":31411,"corporation":false,"usgs":true,"family":"Gates","given":"Paul","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":398144,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Furlong, E. T. 0000-0002-7305-4603","orcid":"https://orcid.org/0000-0002-7305-4603","contributorId":98346,"corporation":false,"usgs":true,"family":"Furlong","given":"E. T.","affiliations":[],"preferred":false,"id":398148,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Ferrer, I.","contributorId":97260,"corporation":false,"usgs":true,"family":"Ferrer","given":"I.","email":"","affiliations":[],"preferred":false,"id":398147,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70023509,"text":"70023509 - 2001 - Impact of climate and parent material on chemical weathering in Loess-derived soils of the Mississippi River valley","interactions":[],"lastModifiedDate":"2022-12-23T18:02:11.297181","indexId":"70023509","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3420,"text":"Soil Science Society of America Journal","active":true,"publicationSubtype":{"id":10}},"title":"Impact of climate and parent material on chemical weathering in Loess-derived soils of the Mississippi River valley","docAbstract":"Peoria Loess-derived soils on uplands east of the Mississippi River valley were studied from Louisiana to Iowa, along a south-to-north gradient of decreasing precipitation and temperature. Major element analyses of deep loess in Mississippi and Illinois show that the composition of the parent material is similar in the northern and southern parts of the valley. We hypothesized that in the warmer, wetter parts of the transect, mineral weathering should be greater than in the cooler, drier parts of the transect. Profile average values of CaO/TiO2, MgO/TiO2, K2O/TiO2 and Na2O/TiO2, Sr/Zr, Ba/Zr, and Rb/Zr represent proxies for depletion of loess minerals such as calcite, dolomite, hornblende, mica, and plagioclase. All ratios show increases from south to north, supporting the hypothesis of greater chemical weathering in the southern part of the valley. An unexpected result is that profile average values of Al2O3/TiO2 and Fe2O3/TiO2 (proxies for the relative abundance of clay minerals) show increases from south to north. This finding, while contrary to the evidence of greater chemical weathering in the southern part of the transect, is consistent with an earlier study which showed higher clay contents in Bt horizons of loess-derived soils in the northern part of the transect. We hypothesize that soils in the northern part of the valley received fine-grained loess from sources to the west of the Mississippi River valley either late in the last glacial period, during the Holocene or both. In contrast, soils in the southern part of the valley were unaffected by such additions.
","language":"English","publisher":"Soil Science Society","doi":"10.2136/sssaj2001.1761","issn":"03615995","usgsCitation":"Muhs, D., Bettis, E., Been, J., and McGeehin, J., 2001, Impact of climate and parent material on chemical weathering in Loess-derived soils of the Mississippi River valley: Soil Science Society of America Journal, v. 65, no. 6, p. 1761-1777, https://doi.org/10.2136/sssaj2001.1761.","productDescription":"17 p.","startPage":"1761","endPage":"1777","costCenters":[],"links":[{"id":232653,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Arkansas, Illinois, Iowa, Kentucky, Louisiana, Mississippi, Missouri, Tennessee, Wisconsin","otherGeospatial":"Mississippi River Valley","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -91.92101739768592,\n 30.745236325390508\n ],\n [\n -91.26276996816591,\n 30.745223393791434\n ],\n [\n -91.26119907843233,\n 31.501794049950348\n ],\n [\n -90.65415266395712,\n 32.28782464081513\n ],\n [\n -90.80033934781983,\n 33.002207154484125\n ],\n [\n -90.72799900533826,\n 33.80500708711324\n ],\n [\n -89.84790814312959,\n 34.892530015067095\n ],\n [\n -89.434030676225,\n 36.07940701674747\n ],\n [\n -89.08300656124574,\n 36.350713126161665\n ],\n [\n -88.9159708331951,\n 36.98993925855281\n ],\n [\n -89.30871396819607,\n 37.743522956188244\n ],\n [\n -90.0645086005942,\n 38.32610022734718\n ],\n [\n -89.74466455809669,\n 38.75413259624344\n ],\n [\n -90.3795236274436,\n 39.28056918504862\n ],\n [\n -91.11342761200302,\n 39.8046507854373\n ],\n [\n -91.15566971529816,\n 40.27366606589638\n ],\n [\n -90.71591548275154,\n 40.89945953341336\n ],\n [\n -90.77964496350887,\n 41.284926473632424\n ],\n [\n -90.36297910470967,\n 41.317471264762275\n ],\n [\n -89.78704345457874,\n 41.94628081065335\n ],\n [\n -90.68524850766028,\n 42.85942099527375\n ],\n [\n -90.84309014947246,\n 43.48882672609571\n ],\n [\n -91.4221357727177,\n 43.4899804524637\n ],\n [\n -91.18749792066657,\n 42.54000415449812\n ],\n [\n -90.44422517568728,\n 41.88121211885803\n ],\n [\n -91.21738663656257,\n 41.479469211855616\n ],\n [\n -91.33408628539468,\n 41.233985575950584\n ],\n [\n -91.17412484030177,\n 40.98861913791299\n ],\n [\n -91.65525847001453,\n 40.50031910925233\n ],\n [\n -91.61375248491436,\n 39.734634896445755\n ],\n [\n -90.97788582035349,\n 39.11645652259517\n ],\n [\n -90.52653760209114,\n 38.0226126481557\n ],\n [\n -89.77722878038122,\n 37.55739189448239\n ],\n [\n -89.61530613927766,\n 36.82446879434379\n ],\n [\n -91.49688472273357,\n 33.739905027820654\n ],\n [\n -91.30423081879928,\n 32.30559941916022\n ],\n [\n -92.02903571192775,\n 31.316288983046135\n ],\n [\n -91.92101739768592,\n 30.745236325390508\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"65","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a38b6e4b0c8380cd61677","contributors":{"authors":[{"text":"Muhs, D.R. 0000-0001-7449-251X","orcid":"https://orcid.org/0000-0001-7449-251X","contributorId":61460,"corporation":false,"usgs":true,"family":"Muhs","given":"D.R.","affiliations":[],"preferred":false,"id":397872,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bettis, E. Arthur III","contributorId":72822,"corporation":false,"usgs":true,"family":"Bettis","given":"E. Arthur","suffix":"III","affiliations":[],"preferred":false,"id":397873,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Been, J.","contributorId":24949,"corporation":false,"usgs":true,"family":"Been","given":"J.","email":"","affiliations":[],"preferred":false,"id":397870,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"McGeehin, J. P. 0000-0002-5320-6091","orcid":"https://orcid.org/0000-0002-5320-6091","contributorId":48593,"corporation":false,"usgs":true,"family":"McGeehin","given":"J. P.","affiliations":[],"preferred":false,"id":397871,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70023640,"text":"70023640 - 2001 - Olivine-liquid relations of lava erupted by Kilauea volcano from 1994 to 1998: Implications for shallow magmatic processes associated with the ongoing east-rift-zone eruption","interactions":[],"lastModifiedDate":"2022-08-24T16:47:22.112866","indexId":"70023640","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1177,"text":"Canadian Mineralogist","active":true,"publicationSubtype":{"id":10}},"title":"Olivine-liquid relations of lava erupted by Kilauea volcano from 1994 to 1998: Implications for shallow magmatic processes associated with the ongoing east-rift-zone eruption","docAbstract":"From 1994 through 1998, the eruption of Kîlauea, in Hawai’i, was dominated by steady-state effusion at Pu‘u ‘Ô‘ô that was briefly disrupted by an eruption 4 km uprift at Nāpau Crater on January 30, 1997. In this paper, I describe the systematic relations of whole-rock, glass, olivine, and olivine-inclusion compositions of lava samples collected throughout this interval. This suite comprises vent samples and tube-contained flows collected at variable distances from the vent. The glass composition of tube lava varies systematically with distance and allows for the “vent-correction” of glass thermometry and olivine–liquid KD as a function of tube-transport distance. Combined olivine–liquid data for vent samples and “vent-corrected” lava-tube samples are used to document pre-eruptive magmatic conditions. KD values determined for matrix glasses and forsterite cores define three types of olivine phenocrysts: type A (in equilibrium with host glass), type B (Mg-rich relative to host glass) and type C (Mg-poor relative to host glass). All three types of olivine have a cognate association with melts that are present within the shallow magmatic plumbing system during this interval. During steady-state eruptive activity, the compositions of whole-rock, glass and most olivine phenocrysts (type A) all vary sympathetically over time and as influenced by changes of magmatic pressure within the summit-rift-zone plumbing system. Type-A olivine is interpreted as having grown during passage from the summit magma-chamber along the east-rift-zone conduit. Type-B olivine (high Fo) is consistent with equilibrium crystallization from bulk-rock compositions and is likely to have grown within the summit magma-chamber. Lower-temperature, fractionated lava was erupted during non-steady-state activity of the Nāpau Crater eruption. Type-A and type-B olivine–liquid relations indicate that this lava is a mixture of rift-stored and summit-derived magmas. Post- Nāpau lava (at Pu‘u ‘Ô‘ô) gradually increases in temperature and MgO content, and contains type-C olivine with complex zoning, indicating magma hybridization associated with the flushing of rift-stored components through the eruption conduit.
","language":"English","publisher":"Mineralogical Association of Canada","doi":"10.2113/gscanmin.39.2.239","usgsCitation":"Thornber, C.R., 2001, Olivine-liquid relations of lava erupted by Kilauea volcano from 1994 to 1998: Implications for shallow magmatic processes associated with the ongoing east-rift-zone eruption: Canadian Mineralogist, v. 39, no. 2, p. 239-266, https://doi.org/10.2113/gscanmin.39.2.239.","productDescription":"28 p.","startPage":"239","endPage":"266","numberOfPages":"28","costCenters":[],"links":[{"id":232224,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Hawaii","otherGeospatial":"Kilauea Volcano","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -155.401611328125,\n 19.169815723556237\n ],\n [\n -155.01434326171872,\n 19.321511226817176\n ],\n [\n -155.137939453125,\n 19.469181787843322\n ],\n [\n -155.30548095703125,\n 19.43421929772403\n ],\n [\n -155.40298461914062,\n 19.338357615423384\n ],\n [\n -155.47164916992188,\n 19.233363381183896\n ],\n [\n -155.401611328125,\n 19.169815723556237\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"39","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a6d6ce4b0c8380cd75125","contributors":{"authors":[{"text":"Thornber, Carl R. cthornber@usgs.gov","contributorId":2016,"corporation":false,"usgs":true,"family":"Thornber","given":"Carl","email":"cthornber@usgs.gov","middleInitial":"R.","affiliations":[{"id":157,"text":"Cascades Volcano Observatory","active":false,"usgs":true}],"preferred":false,"id":398294,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70023639,"text":"70023639 - 2001 - A new tracer‐density criterion for heterogeneous porous media","interactions":[],"lastModifiedDate":"2018-03-30T10:22:29","indexId":"70023639","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3722,"text":"Water Resources Research","onlineIssn":"1944-7973","printIssn":"0043-1397","active":true,"publicationSubtype":{"id":10}},"title":"A new tracer‐density criterion for heterogeneous porous media","docAbstract":"Tracer experiments provide information about aquifer material properties vital for accurate site characterization. Unfortunately, density‐induced sinking can distort tracer movement, leading to an inaccurate assessment of material properties. Yet existing criteria for selecting appropriate tracer concentrations are based on analysis of homogeneous media instead of media with heterogeneities typical of field sites. This work introduces a hydraulic‐gradient correction for heterogeneous media and applies it to a criterion previously used to indicate density‐induced instabilities in homogeneous media. The modified criterion was tested using a series of two‐dimensional heterogeneous intermediate‐scale tracer experiments and data from several detailed field tracer tests. The intermediate‐scale experimental facility (10.0×1.2×0.06 m) included both homogeneous and heterogeneous (σln k2 = 1.22) zones. The field tracer tests were less heterogeneous (0.24 < σln k2 < 0.37), but measurements were sufficient to detect density‐induced sinking. Evaluation of the modified criterion using the experiments and field tests demonstrates that the new criterion appears to account for the change in density‐induced sinking due to heterogeneity. The criterion demonstrates the importance of accounting for heterogeneity to predict density‐induced sinking and differences in the onset of density‐induced sinking in two‐ and three‐dimensional systems.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2000WR900287","usgsCitation":"Barth, G.R., Illangasekare, T.H., Hill, M.C., and Rajaram, H., 2001, A new tracer‐density criterion for heterogeneous porous media: Water Resources Research, v. 37, no. 1, p. 21-31, https://doi.org/10.1029/2000WR900287.","productDescription":"11 p.","startPage":"21","endPage":"31","costCenters":[],"links":[{"id":479005,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2000wr900287","text":"Publisher Index Page"},{"id":232182,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"37","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e4bae4b0c8380cd4689d","contributors":{"authors":[{"text":"Barth, Gilbert R.","contributorId":15374,"corporation":false,"usgs":false,"family":"Barth","given":"Gilbert","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":398290,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Illangasekare, Tissa H.","contributorId":194933,"corporation":false,"usgs":false,"family":"Illangasekare","given":"Tissa","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":398292,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hill, Mary C. mchill@usgs.gov","contributorId":974,"corporation":false,"usgs":true,"family":"Hill","given":"Mary","email":"mchill@usgs.gov","middleInitial":"C.","affiliations":[{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":true,"id":398293,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Rajaram, Harihar","contributorId":194934,"corporation":false,"usgs":false,"family":"Rajaram","given":"Harihar","email":"","affiliations":[],"preferred":false,"id":398291,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70023638,"text":"70023638 - 2001 - Abiotic vs. biotic influences on habitat selection of coexisting species: Climate change impacts?","interactions":[],"lastModifiedDate":"2022-10-07T18:25:07.977719","indexId":"70023638","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1465,"text":"Ecology","active":true,"publicationSubtype":{"id":10}},"title":"Abiotic vs. biotic influences on habitat selection of coexisting species: Climate change impacts?","docAbstract":"Species are commonly segregated along gradients of microclimate and vegetation. I explore the question of whether segregation is the result of microhabitat partitioning (biotic effects) or choice of differing microclimates (abiotic effects). I explored this question for four ground-nesting bird species that are segregated along a microclimate and vegetation gradient in Arizona. Birds shifted position of their nests on the microhabitat and microclimate gradient in response to changing precipitation over nine years. Similarly, annual bird abundance varied with precipitation across 12 yr. Those shifts in abundance and nesting microhabitat with changing precipitation demonstrate the importance of abiotic influences on bird distributions and habitat choice. However, nest-site shifts and microhabitat use also appear to be influenced by interactions among coexisting species. Moreover, shifts in habitat use by all species caused nest predation (i.e., biotic) costs that increased with increasing distance along the microclimate gradient. These results indicate that abiotic and biotic costs can strongly interact to influence microhabitat choice and abundances of coexisting species. Global climate change impacts have been considered largely in terms of simple distributional shifts, but these results indicate that shifts can also increase biotic costs when species move into habitat types for which they are poorly adapted or that create new biotic interactions.","language":"English","publisher":"Ecological Society of America","doi":"10.1890/0012-9658(2001)082[0175:AVBIOH]2.0.CO;2","issn":"00129658","usgsCitation":"Martin, T.E., 2001, Abiotic vs. biotic influences on habitat selection of coexisting species: Climate change impacts?: Ecology, v. 82, no. 1, p. 175-188, https://doi.org/10.1890/0012-9658(2001)082[0175:AVBIOH]2.0.CO;2.","productDescription":"14 p.","startPage":"175","endPage":"188","costCenters":[],"links":[{"id":232181,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Arizona","otherGeospatial":"Mogollon Rim","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -110.12695312499999,\n 31.363018491291182\n ],\n [\n -109.061279296875,\n 31.325486676506983\n ],\n [\n -109.0283203125,\n 33.458942753687644\n ],\n [\n -109.962158203125,\n 33.578014746143985\n ],\n [\n -110.55541992187499,\n 34.279914398549934\n ],\n [\n -111.29150390625,\n 34.56990638085636\n ],\n [\n -111.456298828125,\n 34.903952965590065\n ],\n [\n -111.785888671875,\n 35.074964853989556\n ],\n [\n -113.32397460937499,\n 35.64836915737426\n ],\n [\n -114.04907226562499,\n 36.11125252076156\n ],\n [\n -114.158935546875,\n 35.96911507577482\n ],\n [\n -114.444580078125,\n 35.89795019335754\n ],\n [\n -114.14794921875,\n 34.939985151560435\n ],\n [\n -113.587646484375,\n 34.352506668675936\n ],\n [\n -112.78564453124999,\n 34.06176136129718\n ],\n [\n -112.00561523437499,\n 33.50475906922609\n ],\n [\n -110.928955078125,\n 32.79651010951669\n ],\n [\n -110.994873046875,\n 32.40779154205701\n ],\n [\n -110.12695312499999,\n 31.363018491291182\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"82","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e641e4b0c8380cd472b7","contributors":{"authors":[{"text":"Martin, T. E.","contributorId":10911,"corporation":false,"usgs":true,"family":"Martin","given":"T.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":398289,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70023466,"text":"70023466 - 2001 - Water source to four U.S. wetlands: Implications for wetland management","interactions":[],"lastModifiedDate":"2012-03-12T17:20:10","indexId":"70023466","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3750,"text":"Wetlands","onlineIssn":"1943-6246","printIssn":"0277-5212","active":true,"publicationSubtype":{"id":10}},"title":"Water source to four U.S. wetlands: Implications for wetland management","docAbstract":"Results of long-term field studies of wetlands in four different hydrogeologic and climatic settings in the United States indicate that each has considerably different sources of water, which affects their response to climate variability and land-use practices. A fen wetland in New Hampshire is supplied almost entirely by ground water that originates as seepage from Mirror Lake; therefore, stream discharge from the fen closely follows the pattern of Mirror Lake stage fluctuations. A fen wetland in northern Minnesota is supplied largely by discharge from a regional ground-water flow system that has its recharge area 1 to 2 km to the east. Because of the size of this wetland's ground-water watershed, stream discharge from the fen has little variability. A prairie-pothole wetland in North Dakota receives more than 90 percent of its water from precipitation and loses more than 90 percent of its water to evapotranspiration, resulting in highly variable seasonal and annual water levels. A wetland in the sandhills of Nebraska lies in a regional ground-water flow field that extends for tens of kilometers and that contains numerous lakes and wetlands. The wetland receives water that moves through the ground-water system from the upgradient lakes and from ground water in local flow systems that are recharged between the lakes. The difference in sources of water to these wetlands implies that they would require different techniques to protect their water supply and water quality.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Wetlands","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"02775212","usgsCitation":"Winter, T.C., Rosenberry, D., Buso, D., and Merk, D., 2001, Water source to four U.S. wetlands: Implications for wetland management: Wetlands, v. 21, no. 4, p. 462-473.","startPage":"462","endPage":"473","numberOfPages":"12","costCenters":[],"links":[{"id":232650,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"21","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bcc74e4b08c986b32db60","contributors":{"authors":[{"text":"Winter, T. C.","contributorId":23485,"corporation":false,"usgs":true,"family":"Winter","given":"T.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":397747,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Rosenberry, D.O. 0000-0003-0681-5641","orcid":"https://orcid.org/0000-0003-0681-5641","contributorId":38500,"corporation":false,"usgs":true,"family":"Rosenberry","given":"D.O.","affiliations":[],"preferred":true,"id":397749,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Buso, D.C.","contributorId":31392,"corporation":false,"usgs":true,"family":"Buso","given":"D.C.","email":"","affiliations":[],"preferred":false,"id":397748,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Merk, D.A.","contributorId":86357,"corporation":false,"usgs":true,"family":"Merk","given":"D.A.","email":"","affiliations":[],"preferred":false,"id":397750,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70022824,"text":"70022824 - 2001 - Evidence and characteristics of hydrolytic disproportionation of organic matter during metasomatic processes","interactions":[],"lastModifiedDate":"2012-03-12T17:20:06","indexId":"70022824","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","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":"Evidence and characteristics of hydrolytic disproportionation of organic matter during metasomatic processes","docAbstract":"Petroleum-geochemical analyses of carbonaceous regionally metamorphosed rocks, carbonaceous rocks from ore deposits, and alkalic plutonic rocks from diverse settings, demonstrated the presence of very low to moderately low concentrations of solvent-extractable organic matter, this observation in spite of the fact that some of these rocks were exposed to extremely high metamorphic temperatures. Biomarker and ??13C analyses established that the extractable organic matter originated as sedimentary-derived hydrocarbons. However, the chemistry of the extractable bitumen has been fundamentally transformed from that found in sediment bitumen and oils. Asphaltenes and resins, as defined in the normal petroleum-geochemical sense, are completely missing. The principal aromatic hydrocarbons present in oils and sediment bitumens (especially the methylated naphthalenes) are either in highly reduced concentrations or are missing altogether, Instead, aromatic hydrocarbons typical of sediment bitumens and oils are very minor, and a number of unidentified compounds and oxygen-bearing compounds are dominant. Relatively high concentrations of alkylated benzenes are typical. The polar \"resin\" fraction, eluted during column chromatography, is the principal compound group, by weight, being composed of six to eight dominant peaks present in all samples, despite the great geologic diversity of the samples. These, and other, observations suggest that a strong drive towards equilibrium exists in the \"bitumen.\" Gas chromatograms of the saturated hydrocarbons commonly have a pronounced hump in both the n-paraffins and naphthenes, centered near the C19 to C26 carbon numbers, and a ubiquitos minimum in the n-paraffin distribution near n-C12 to n-C14. Multiple considerations dictate that the bitumen in the samples is indigenous and did not originate from either surficial field contamination or from laboratory procedures. Our observations are consistent with the hydrolytic disproportion of organic matter (HDOM), in which water and organic matter, including hydrocarbons, easily exchange hydrogen or oxygen with one another under certain conditions (Helgeson et al., 1993). The process appears to take place via well-known organic-chemical redox reaction pathways and is most evident in open-fluid systems. The conclusion that HDOM took place in the analyzed samples, thus producing the chemistry of the extractable bitumen, is supported by numerous previously published organic-geochemical studies of metamorphic, volcanic, plutonic, and ore-deposit-related rocks by other investigators. HDOM is suggested as an unrecognized geologic agent of fundamental importance. The process appears to control major chemical reactions in diverse geologic environments including, but not limited to, petroleum geology and geochemistry, regional metamorphism, and base- and precious-metal ore deposition. Copyright ?? 2001 Elsevier Science Ltd.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Geochimica et Cosmochimica Acta","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0016-7037(01)00762-1","issn":"00167037","usgsCitation":"Price, L., and Dewitt, E., 2001, Evidence and characteristics of hydrolytic disproportionation of organic matter during metasomatic processes: Geochimica et Cosmochimica Acta, v. 65, no. 21, p. 3791-3826, https://doi.org/10.1016/S0016-7037(01)00762-1.","startPage":"3791","endPage":"3826","numberOfPages":"36","costCenters":[],"links":[{"id":208009,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0016-7037(01)00762-1"},{"id":233354,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"65","issue":"21","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0d27e4b0c8380cd52e40","contributors":{"authors":[{"text":"Price, L.C.","contributorId":48575,"corporation":false,"usgs":true,"family":"Price","given":"L.C.","email":"","affiliations":[],"preferred":false,"id":395030,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Dewitt, E.","contributorId":108257,"corporation":false,"usgs":true,"family":"Dewitt","given":"E.","email":"","affiliations":[],"preferred":false,"id":395031,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70023637,"text":"70023637 - 2001 - Investigating a physical basis for spectroscopic estimates of leaf nitrogen concentration","interactions":[],"lastModifiedDate":"2012-03-12T17:20:03","indexId":"70023637","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3254,"text":"Remote Sensing of Environment","printIssn":"0034-4257","active":true,"publicationSubtype":{"id":10}},"title":"Investigating a physical basis for spectroscopic estimates of leaf nitrogen concentration","docAbstract":"The reflectance spectra of dried and ground plant foliage are examined for changes directly due to increasing nitrogen concentration. A broadening of the 2.1-??m absorption feature is observed as nitrogen concentration increases. The broadening is shown to arise from two absorptions at 2.054 ??m and 2.172 ??m. The wavelength positions of these absorptions coincide with the absorption characteristics of the nitrogen-containing amide bonds in proteins. The observed presence of these absorption features in the reflectance spectra of dried foliage is suggested to form a physical basis for high correlations established by stepwise multiple linear regression techniques between the reflectance of dry plant samples and their nitrogen concentration. The consistent change in the 2.1-??m absorption feature as nitrogen increases and the offset position of protein absorptions compared to those of other plant components together indicate that a generally applicable algorithm may be developed for spectroscopic estimates of nitrogen concentration from the reflectance spectra of dried plant foliage samples. ?? 2001 Published by Elsevier Science Ireland Ltd.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Remote Sensing of Environment","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0034-4257(00)00163-2","issn":"00344257","usgsCitation":"Kokaly, R., 2001, Investigating a physical basis for spectroscopic estimates of leaf nitrogen concentration: Remote Sensing of Environment, v. 75, no. 2, p. 153-161, https://doi.org/10.1016/S0034-4257(00)00163-2.","startPage":"153","endPage":"161","numberOfPages":"9","costCenters":[],"links":[{"id":207306,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0034-4257(00)00163-2"},{"id":232144,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"75","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a3e65e4b0c8380cd63d45","contributors":{"authors":[{"text":"Kokaly, R.F. 0000-0003-0276-7101","orcid":"https://orcid.org/0000-0003-0276-7101","contributorId":42381,"corporation":false,"usgs":true,"family":"Kokaly","given":"R.F.","affiliations":[],"preferred":false,"id":398288,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70023597,"text":"70023597 - 2001 - Microbiological quality of Puget Sound Basin streams and identification of contaminant sources","interactions":[],"lastModifiedDate":"2016-05-27T13:02:53","indexId":"70023597","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2529,"text":"Journal of the American Water Resources Association","active":true,"publicationSubtype":{"id":10}},"title":"Microbiological quality of Puget Sound Basin streams and identification of contaminant sources","docAbstract":"Fecal coliforms, Escherichia coli, enterococci, and somatic coliphages were detected in samples from 31 sites on streams draining urban and agricultural regions of the Puget Sound Basin Lowlands. Densities of bacteria in 48 and 71 percent of the samples exceeded U.S. Environmental Protection Agency's freshwater recreation criteria for Escherichia coli and enterococci, respectively, and 81 percent exceeded Washington State fecal coliform standards. Male-specific coliphages were detected in samples from 15 sites. Male-specific F+RNA coliphages isolated from samples taken at South Fork Thornton and Longfellow Creeks were serotyped as Group II, implicating humans as potential contaminant sources. These two sites are located in residential, urban areas. F+RNA coliphages in samples from 10 other sites, mostly in agricultural or rural areas, were serotyped as Group I, implicating non-human animals as likely sources. Chemicals common to wastewater, including fecal sterols, were detected in samples from several urban streams, and also implicate humans, at least in part, as possible sources of fecal bacteria and viruses to the streams.
","language":"English","publisher":"Wiley","doi":"10.1111/j.1752-1688.2001.tb00978.x","issn":"1093474X","usgsCitation":"Embrey, S., 2001, Microbiological quality of Puget Sound Basin streams and identification of contaminant sources: Journal of the American Water Resources Association, v. 37, no. 2, p. 407-421, https://doi.org/10.1111/j.1752-1688.2001.tb00978.x.","productDescription":"15 p.","startPage":"407","endPage":"421","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":622,"text":"Washington Water Science Center","active":true,"usgs":true}],"links":[{"id":232140,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"37","issue":"2","noUsgsAuthors":false,"publicationDate":"2007-06-08","publicationStatus":"PW","scienceBaseUri":"505a5668e4b0c8380cd6d591","contributors":{"authors":[{"text":"Embrey, S.S.","contributorId":8448,"corporation":false,"usgs":true,"family":"Embrey","given":"S.S.","affiliations":[],"preferred":false,"id":398165,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70023253,"text":"70023253 - 2001 - Seedling mortality in Hawaiian rain forest: The role of small-scale physical disturbance","interactions":[],"lastModifiedDate":"2022-08-24T15:51:24.853482","indexId":"70023253","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1045,"text":"Biotropica","active":true,"publicationSubtype":{"id":10}},"title":"Seedling mortality in Hawaiian rain forest: The role of small-scale physical disturbance","docAbstract":"Most montane rain forests on the island of Hawaii consist of a closed canopy formed by Cibotium spp. tree ferns beneath an open canopy of emergent Metrosideros polymorpha trees. We used artificial seedlings to assess the extent to which physical disturbance caused by the senescing fronds of tree ferns and the activities of feral pigs might limit tree regeneration. Artificial seedlings were established terrestrially (N= 300) or epiphytically (N = 300) on tree fern stems. Half of the seedlings on each substrate were in an exclosure lacking feral pigs and half were in forest with pigs present. After one year, the percentage of seedlings damaged was significantly greater among terrestrial seedlings (25.7%) than epiphytic seedlings (11.3%). Significantly more terrestrial seedlings were damaged in the presence of pigs (31.3%) than in the absence of pigs (20.0%). Senescing fronds of tree ferns were responsible for 60.3 percent of the damaged seedlings. Physical disturbance is potentially a major cause of seedling mortality and may reduce the expected half-life of a seedling cohort to less than two years.
","language":"English","publisher":"Wiley","doi":"10.1111/j.1744-7429.2001.tb00182.x","usgsCitation":"Drake, D.R., and Pratt, L.W., 2001, Seedling mortality in Hawaiian rain forest: The role of small-scale physical disturbance: Biotropica, v. 33, no. 2, p. 319-323, https://doi.org/10.1111/j.1744-7429.2001.tb00182.x.","productDescription":"5 p.","startPage":"319","endPage":"323","numberOfPages":"5","costCenters":[{"id":5049,"text":"Pacific Islands Ecosys Research Center","active":true,"usgs":true}],"links":[{"id":232317,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Hawaii","otherGeospatial":"Hawaii Volcanoes National Park","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -155.0177764892578,\n 19.332526369847702\n ],\n [\n -155.0438690185547,\n 19.330582575049508\n ],\n [\n -155.0994873046875,\n 19.388238642115578\n ],\n [\n -155.1228332519531,\n 19.39601093343177\n ],\n [\n -155.13587951660156,\n 19.379170499941292\n ],\n [\n -155.23200988769528,\n 19.397953948267734\n ],\n [\n -155.23681640625,\n 19.41867799583191\n ],\n [\n -155.2704620361328,\n 19.436809370143173\n ],\n [\n -155.28007507324216,\n 19.434866819701945\n ],\n [\n -155.2972412109375,\n 19.454938719968595\n ],\n [\n -155.32470703125,\n 19.44652177370614\n ],\n [\n -155.36109924316406,\n 19.383056908418272\n ],\n [\n -155.39199829101562,\n 19.34289288466279\n ],\n [\n -155.42152404785156,\n 19.24632927300332\n ],\n [\n -155.43731689453125,\n 19.177598387749878\n ],\n [\n -155.43731689453125,\n 19.160735484156255\n ],\n [\n -155.3638458251953,\n 19.20159262068579\n ],\n [\n -155.33294677734375,\n 19.23206673568465\n ],\n [\n -155.28831481933594,\n 19.265127996468802\n ],\n [\n -155.1825714111328,\n 19.25605301966429\n ],\n [\n -155.11322021484375,\n 19.279387659275706\n ],\n [\n -155.0164031982422,\n 19.329286698998818\n ],\n [\n -155.0177764892578,\n 19.332526369847702\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"33","issue":"2","noUsgsAuthors":false,"publicationDate":"2006-03-15","publicationStatus":"PW","scienceBaseUri":"505b8acbe4b08c986b3173ae","contributors":{"authors":[{"text":"Drake, Donald R.","contributorId":27765,"corporation":false,"usgs":true,"family":"Drake","given":"Donald","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":397028,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Pratt, Linda W. lpratt@usgs.gov","contributorId":3708,"corporation":false,"usgs":true,"family":"Pratt","given":"Linda","email":"lpratt@usgs.gov","middleInitial":"W.","affiliations":[],"preferred":true,"id":397027,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022705,"text":"70022705 - 2001 - Identifying variably saturated water-flow patterns in a steep hillslope under intermittent heavy rainfall","interactions":[],"lastModifiedDate":"2012-03-12T17:20:39","indexId":"70022705","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1923,"text":"Hydrogeology Journal","active":true,"publicationSubtype":{"id":10}},"title":"Identifying variably saturated water-flow patterns in a steep hillslope under intermittent heavy rainfall","docAbstract":"The objective of this paper is to identify water-flow patterns in part of an active landslide, through the use of numerical simulations and data obtained during a field study. The approaches adopted include measuring rainfall events and pore-pressure responses in both saturated and unsaturated soils at the site. To account for soil variability, the Richards equation is solved within deterministic and stochastic frameworks. The deterministic simulations considered average water-retention data, adjusted retention data to account for stones or cobbles, retention functions for a heterogeneous pore structure, and continuous retention functions for preferential flow. The stochastic simulations applied the Monte Carlo approach which considers statistical distribution and autocorrelation of the saturated conductivity and its cross correlation with the retention function. Although none of the models is capable of accurately predicting field measurements, appreciable improvement in accuracy was attained using stochastic, preferential flow, and heterogeneous pore-structure models. For the current study, continuum-flow models provide reasonable accuracy for practical purposes, although they are expected to be less accurate than multi-domain preferential flow models.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Hydrogeology Journal","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1007/s100400100129","issn":"14312174","usgsCitation":"El-Kadi, A., and Torikai, J., 2001, Identifying variably saturated water-flow patterns in a steep hillslope under intermittent heavy rainfall: Hydrogeology Journal, v. 9, no. 3, p. 231-242, https://doi.org/10.1007/s100400100129.","startPage":"231","endPage":"242","numberOfPages":"12","costCenters":[],"links":[{"id":208162,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s100400100129"},{"id":233674,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"9","issue":"3","noUsgsAuthors":false,"publicationDate":"2014-02-01","publicationStatus":"PW","scienceBaseUri":"505a385de4b0c8380cd61545","contributors":{"authors":[{"text":"El-Kadi, A. I.","contributorId":103838,"corporation":false,"usgs":true,"family":"El-Kadi","given":"A. I.","affiliations":[],"preferred":false,"id":394605,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Torikai, J.D.","contributorId":93926,"corporation":false,"usgs":true,"family":"Torikai","given":"J.D.","affiliations":[],"preferred":false,"id":394604,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022732,"text":"70022732 - 2001 - Moss and lichen cover mapping at local and regional scales in the boreal forest ecosystem of central Canada","interactions":[],"lastModifiedDate":"2015-08-27T13:46:24","indexId":"70022732","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2316,"text":"Journal of Geophysical Research D: Atmospheres","active":true,"publicationSubtype":{"id":10}},"title":"Moss and lichen cover mapping at local and regional scales in the boreal forest ecosystem of central Canada","docAbstract":"Mosses and lichens are important components of boreal landscapes [Vitt et al., 1994; Bubier et al., 1997]. They affect plant productivity and belowground carbon sequestration and alter the surface runoff and energy balance. We report the use of multiresolution satellite data to map moss and lichens over the BOREAS region at a 10 m, 30 m, and 1 km scales. Our moss and lichen classification at the 10 m scale is based on ground observations of associations among soil drainage classes, overstory composition, and cover type among four broad classes of ground cover (feather, sphagnum, and brown mosses and lichens). For our 30 m map, we used field observations of ground cover-overstory associations to map mosses and lichens in the BOREAS southern study area (SSA). To scale up to a 1 km (AVHRR) moss map of the BOREAS region, we used the TM SSA mosaics plus regional field data to identify AVHRR overstory-ground cover associations. We found that: 1) ground cover, overstory composition and density are highly correlated, permitting inference of moss and lichen cover from satellite-based land cover classifications; 2) our 1 km moss map reveals that mosses dominate the boreal landscape of central Canada, thereby a significant factor for water, energy, and carbon modeling; 3) TM and AVHRR moss cover maps are comparable; 4) satellite data resolution is important; particularly in detecting the smaller wetland features, lakes, and upland jack pine sites; and 5) distinct regional patterns of moss and lichen cover correspond to latitudinal and elevational gradients. Copyright 2001 by the American Geophysical Union.
","language":"English","publisher":"Wiley","doi":"10.1029/2001JD000509","issn":"01480227","usgsCitation":"Rapalee, G., Steyaert, L.T., and Hall, F., 2001, Moss and lichen cover mapping at local and regional scales in the boreal forest ecosystem of central Canada: Journal of Geophysical Research D: Atmospheres, v. 106, no. D24, p. 33551-33563, https://doi.org/10.1029/2001JD000509.","startPage":"33551","endPage":"33563","numberOfPages":"13","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":222,"text":"Earth Resources Observation and Science (EROS) Center","active":true,"usgs":true}],"links":[{"id":487430,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2001jd000509","text":"Publisher Index Page"},{"id":233566,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"106","issue":"D24","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5e88e4b0c8380cd70ad5","contributors":{"authors":[{"text":"Rapalee, G.","contributorId":35904,"corporation":false,"usgs":true,"family":"Rapalee","given":"G.","email":"","affiliations":[],"preferred":false,"id":394695,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Steyaert, L. T.","contributorId":71303,"corporation":false,"usgs":true,"family":"Steyaert","given":"L.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":394697,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hall, F.G.","contributorId":47099,"corporation":false,"usgs":true,"family":"Hall","given":"F.G.","email":"","affiliations":[],"preferred":false,"id":394696,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70022822,"text":"70022822 - 2001 - New constraints on the pyroclastic eruptive history of the Campanian volcanic Plain (Italy)","interactions":[],"lastModifiedDate":"2016-10-12T16:19:58","indexId":"70022822","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2751,"text":"Mineralogy and Petrology","active":true,"publicationSubtype":{"id":10}},"title":"New constraints on the pyroclastic eruptive history of the Campanian volcanic Plain (Italy)","docAbstract":"The ∼ 150 km3 (DRE) trachytic Campanian Ignimbrite, which is situated north-west of Naples, Italy, is one of the largest eruptions in the Mediterranean region in the last 200 ky. Despite centuries of investigation, the age and eruptive history of the Campanian Ignimbrite is still debated, as is the chronology of other significant volcanic events of the Campanian Plain within the last 200–300 ky. New 40Ar/39Ar geochronology defines the age of the Campanian Ignimbrite at 39.28 ± 0.11 ka, about 2 ky older than the previous best estimate. Based on the distribution of the Campanian Ignimbrite and associated uppermost proximal lithic and polyclastic breccias, we suggest that the Campanian Ignimbrite magma was emitted from fissures activated along neotectonic Apennine faults rather than from ring fractures defining a Campi Flegrei caldera. Significantly, new volcanological, geochronological, and geochemical data distinguish previously unrecognized ignimbrite deposits in the Campanian Plain, accurately dated between 157 and 205 ka. These ages, coupled with a xenocrystic sanidine component > 315 ka, extend the volcanic history of this region by over 200 ky. Recent work also identifies a pyroclastic deposit, dated at 18.0 ka, outside of the topographic Campi Flegrei basin, expanding the spatial distribution of post-Campanian Ignimbrite deposits. These new discoveries emphasize the importance of continued investigation of the ages, distribution, volumes, and eruption dynamics of volcanic events associated with the Campanian Plain. Such information is critical for accurate assessment of the volcanic hazards associated with potentially large-volume explosive eruptions in close proximity to the densely populated Neapolitan region.
","language":"English","publisher":"Springer-Verlag","doi":"10.1007/s007100170010","issn":"09300708","usgsCitation":"de Vivo, B., Rolandi, G., Gans, P.B., Calvert, A., Bohrson, W., Spera, F., and Belkin, H., 2001, New constraints on the pyroclastic eruptive history of the Campanian volcanic Plain (Italy): Mineralogy and Petrology, v. 73, no. 1-3, p. 47-65, https://doi.org/10.1007/s007100170010.","productDescription":"19 p.","startPage":"47","endPage":"65","numberOfPages":"19","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":233892,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Italy","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n 14.084472656249998,\n 40.76806170936614\n ],\n [\n 14.084472656249998,\n 42.1104489601222\n ],\n [\n 15.611572265625,\n 42.1104489601222\n ],\n [\n 15.611572265625,\n 40.76806170936614\n ],\n [\n 14.084472656249998,\n 40.76806170936614\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"73","issue":"1-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a6566e4b0c8380cd72ba8","contributors":{"authors":[{"text":"de Vivo, B.","contributorId":50549,"corporation":false,"usgs":false,"family":"de Vivo","given":"B.","affiliations":[],"preferred":false,"id":395021,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Rolandi, G.","contributorId":76472,"corporation":false,"usgs":false,"family":"Rolandi","given":"G.","email":"","affiliations":[],"preferred":false,"id":395022,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Gans, P. B.","contributorId":79913,"corporation":false,"usgs":true,"family":"Gans","given":"P.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":395023,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Calvert, A.","contributorId":105089,"corporation":false,"usgs":true,"family":"Calvert","given":"A.","email":"","affiliations":[],"preferred":false,"id":395026,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Bohrson, W.A.","contributorId":102092,"corporation":false,"usgs":false,"family":"Bohrson","given":"W.A.","affiliations":[],"preferred":false,"id":395025,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Spera, F. J.","contributorId":89315,"corporation":false,"usgs":false,"family":"Spera","given":"F. J.","affiliations":[],"preferred":false,"id":395024,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Belkin, H. E. 0000-0001-7879-6529","orcid":"https://orcid.org/0000-0001-7879-6529","contributorId":38160,"corporation":false,"usgs":true,"family":"Belkin","given":"H. E.","affiliations":[],"preferred":false,"id":395020,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":70023782,"text":"70023782 - 2001 - In situ stimulation of groundwater denitrification with formate to remediate nitrate contamination","interactions":[],"lastModifiedDate":"2018-12-03T09:43:33","indexId":"70023782","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","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":"In situ stimulation of groundwater denitrification with formate to remediate nitrate contamination","docAbstract":"In situ stimulation of denitrification has been proposed as a mechanism to remediate groundwater nitrate contamination. In this study, sodium formate was added to a sand and gravel aquifer on Cape Cod, MA, to test whether formate could serve as a potential electron donor for subsurface denitrification. During 16- and 10-day trials, groundwater from an anoxic nitrate-containing zone (0.5-1.5 mM) was continuously withdrawn, amended with formate and bromide, and pumped back into the aquifer. Concentrations of groundwater constituents were monitored in multilevel samplers after up to 15 m of transport by natural gradient flow. Nitrate and formate concentrations were decreased 80-100% and 60-70%, respectively, with time and subsequent travel distance, while nitrite concentrations inversely increased. The field experiment breakthrough curves were simulated with a two-dimensional site-specific model that included transport, denitrification, and microbial growth. Initial values for model parameters were obtained from laboratory incubations with aquifer core material and then refined to fit field breakthrough curves. The model and the lab results indicated that formate-enhanced nitrite reduction was nearly 4-fold slower than nitrate reduction, but in the lab, nitrite was completely consumed with sufficient exposure time. Results of this study suggest that a long-term injection of formate is necessary to test the remediation potential of this approach for nitrate contamination and that adaptation to nitrite accumulation will be a key determinative factor.In situ stimulation of denitrification has been proposed as a mechanism to remediate groundwater nitrate contamination. In this study, sodium formate was added to a sand and gravel aquifer on Cape Cod, MA, to test whether formate could serve as a potential electron donor for subsurface denitrification. During 16- and 10-day trials, groundwater from an anoxic nitrate-containing zone (0.5-1.5 mM) was continuously withdrawn, amended with formate and bromide, and pumped back into the aquifer. Concentrations of groundwater constituents were monitored in multilevel samplers after up to 15 m of transport by natural gradient flow. Nitrate and formate concentrations were decreased 80-100% and 60-70%, respectively, with time and subsequent travel distance, while nitrite concentrations inversely increased. The field experiment breakthrough curves were simulated with a two-dimensional site-specific model that included transport, denitrification, and microbial growth. Initial values for model parameters were obtained from laboratory incubations with aquifer core material and then refined to fit field breakthrough curves. The model and the lab results indicated that formate-enhanced nitrite reduction was nearly 4-fold slower than nitrate reduction, but in the lab, nitrite was completely consumed with sufficient exposure time. Results of this study suggest that a long-term injection of formate is necessary to test the remediation potential of this approach for nitrate contamination and that adaptation to nitrite accumulation will be a key determinative factor.","language":"English","publisher":"ACS","doi":"10.1021/es001360p","issn":"0013936X","usgsCitation":"Smith, R.L., Miller, D., Brooks, M.H., Widdowson, M., and Killingstad, M., 2001, In situ stimulation of groundwater denitrification with formate to remediate nitrate contamination: Environmental Science & Technology, v. 35, no. 1, p. 196-203, https://doi.org/10.1021/es001360p.","productDescription":"8 p.","startPage":"196","endPage":"203","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":232547,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":207525,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1021/es001360p"}],"volume":"35","issue":"1","noUsgsAuthors":false,"publicationDate":"2000-11-29","publicationStatus":"PW","scienceBaseUri":"505a39abe4b0c8380cd619da","contributors":{"authors":[{"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":398823,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Miller, D.N.","contributorId":36324,"corporation":false,"usgs":true,"family":"Miller","given":"D.N.","email":"","affiliations":[],"preferred":false,"id":398821,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Brooks, M. H.","contributorId":107735,"corporation":false,"usgs":true,"family":"Brooks","given":"M.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":398825,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Widdowson, M.A.","contributorId":46262,"corporation":false,"usgs":true,"family":"Widdowson","given":"M.A.","email":"","affiliations":[],"preferred":false,"id":398822,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Killingstad, M.W.","contributorId":105478,"corporation":false,"usgs":true,"family":"Killingstad","given":"M.W.","email":"","affiliations":[],"preferred":false,"id":398824,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":1001796,"text":"1001796 - 2001 - Mitochondrial phylogeography, subspecific taxonomy, and conservation genetics of sandhill cranes (Grus canadensis; Aves: Gruidae)","interactions":[],"lastModifiedDate":"2022-10-06T16:56:34.406857","indexId":"1001796","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1324,"text":"Conservation Genetics","active":true,"publicationSubtype":{"id":10}},"displayTitle":"Mitochondrial phylogeography, subspecific taxonomy, and conservation genetics of sandhill cranes (Grus canadensis; Aves: Gruidae)","title":"Mitochondrial phylogeography, subspecific taxonomy, and conservation genetics of sandhill cranes (Grus canadensis; Aves: Gruidae)","docAbstract":"Six subspecies of sandhill cranes (Grus canadensis) have been denoted based on perceived morphological and/or breeding locality differences among them. Three subspecies are migratory, breeding from the high arctic in North America and Siberia (lesser sandhill, G. c. canadensis),south through central Canada (Canadian sandhill, G. c. rowani) and into the northern United States (greater sandhill, G. c. tabida). A review of sandhill crane taxonomy indicates that the size variation, on the basis of which these subspecies were named, may be clinal and not diagnostic. The other three subspecies, all listed as endangered or threatened, are non-migratory, resident in Florida (G. c. pratensis), Mississippi (G. c. pulla), and Cuba (G. c. nesiotes). We used analysis of mitochondrial DNA control region (CR) sequences to determine whether haplotypes representing current subspecies show any genetic cohesion or are more consistent with a pattern of clinal variation in morphology. CR sequences indicate that only two highly divergent (5.3%) lineages of sandhill cranes occur in North America: one lineage composed only of arctic-nesting G. c. canadensis, the other of the remaining North American subspecies (we lack data on the Cuban population). The deep split between lineages is consistent with an estimated isolation of approximately 1.5 Mya (mid-Pleistocene), while the distribution of mutational changes within lineages is consistent with an hypothesis of rapid, post-Pleistocene population expansions. No other phylogeographic structuring is concordant with subspecific boundaries, however, analysis of molecular variance indicates that there is significant population genetic differentiation among all subspecies except G. c. tabida and G. c. rowani, which are indistinguishable. We suggest that recognition of the recently named G. c. rowani be abandoned.
","language":"English","publisher":"Springer","doi":"10.1023/A:1012203532300","usgsCitation":"Rhymer, J., Fain, M., Austin, J.E., Johnson, D.H., and Krajewski, C., 2001, Mitochondrial phylogeography, subspecific taxonomy, and conservation genetics of sandhill cranes (Grus canadensis; Aves: Gruidae): Conservation Genetics, v. 2, p. 203-218, https://doi.org/10.1023/A:1012203532300.","productDescription":"15 p.","startPage":"203","endPage":"218","costCenters":[{"id":480,"text":"Northern Prairie Wildlife Research Center","active":true,"usgs":true}],"links":[{"id":129212,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Canada, Cuba, Russia, United States","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -193.7109375,\n 59.355596110016315\n ],\n [\n -195.205078125,\n 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M.G.","contributorId":98671,"corporation":false,"usgs":true,"family":"Fain","given":"M.G.","email":"","affiliations":[],"preferred":false,"id":311799,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Austin, J. E.","contributorId":5999,"corporation":false,"usgs":true,"family":"Austin","given":"J.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":311795,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Johnson, Douglas H. 0000-0002-7778-6641","orcid":"https://orcid.org/0000-0002-7778-6641","contributorId":70327,"corporation":false,"usgs":true,"family":"Johnson","given":"Douglas","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":311797,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Krajewski, C.","contributorId":35679,"corporation":false,"usgs":true,"family":"Krajewski","given":"C.","email":"","affiliations":[],"preferred":false,"id":311796,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70023596,"text":"70023596 - 2001 - Estimating equation for mixed populations of floods in Massachusetts","interactions":[],"lastModifiedDate":"2012-03-12T17:20:02","indexId":"70023596","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2341,"text":"Journal of Hydrologic Engineering","active":true,"publicationSubtype":{"id":10}},"title":"Estimating equation for mixed populations of floods in Massachusetts","docAbstract":"A single equation for estimating the peak flows of annual floods at ungauged sites in Massachusetts was developed by combining the conditional probabilities of floods caused by tropical cyclones and ice-jam releases with the conditional probability of \"ordinary\" floods. Regression equations for these three flood populations demonstrated that two basin characteristics, drainage-basin area and basin head, and frequency of flooding determined the corresponding peak-flow rates.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Hydrologic Engineering","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1061/(ASCE)1084-0699(2001)6:1(72)","issn":"10840699","usgsCitation":"Murphy, P., 2001, Estimating equation for mixed populations of floods in Massachusetts: Journal of Hydrologic Engineering, v. 6, no. 1, p. 72-74, https://doi.org/10.1061/(ASCE)1084-0699(2001)6:1(72).","startPage":"72","endPage":"74","numberOfPages":"3","costCenters":[],"links":[{"id":207303,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1061/(ASCE)1084-0699(2001)6:1(72)"},{"id":232139,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"6","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0b18e4b0c8380cd5257e","contributors":{"authors":[{"text":"Murphy, P.J.","contributorId":91903,"corporation":false,"usgs":true,"family":"Murphy","given":"P.J.","email":"","affiliations":[],"preferred":false,"id":398164,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70023511,"text":"70023511 - 2001 - Comments on \"Failures in detecting volcanic ash from a satellite-based technique\"","interactions":[],"lastModifiedDate":"2012-03-12T17:20:10","indexId":"70023511","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3254,"text":"Remote Sensing of Environment","printIssn":"0034-4257","active":true,"publicationSubtype":{"id":10}},"title":"Comments on \"Failures in detecting volcanic ash from a satellite-based technique\"","docAbstract":"The recent paper by Simpson et al. [Remote Sens. Environ. 72 (2000) 191.] on failures to detect volcanic ash using the 'reverse' absorption technique provides a timely reminder of the danger that volcanic ash presents to aviation and the urgent need for some form of effective remote detection. The paper unfortunately suffers from a fundamental flaw in its methodology and numerous errors of fact and interpretation. For the moment, the 'reverse' absorption technique provides the best means for discriminating volcanic ash clouds from meteorological clouds. The purpose of our comment is not to defend any particular algorithm; rather, we point out some problems with Simpson et al.'s analysis and re-state the conditions under which the 'reverse' absorption algorithm is likely to succeed. ?? 2001 Elsevier Science Inc. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Remote Sensing of Environment","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0034-4257(01)00231-0","issn":"00344257","usgsCitation":"Prata, F., Bluth, G., Rose, B., Schneider, D., and Tupper, A., 2001, Comments on \"Failures in detecting volcanic ash from a satellite-based technique\": Remote Sensing of Environment, v. 78, no. 3, p. 341-346, https://doi.org/10.1016/S0034-4257(01)00231-0.","startPage":"341","endPage":"346","numberOfPages":"6","costCenters":[],"links":[{"id":207604,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0034-4257(01)00231-0"},{"id":232694,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"78","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f7f1e4b0c8380cd4cdc0","contributors":{"authors":[{"text":"Prata, F.","contributorId":44323,"corporation":false,"usgs":true,"family":"Prata","given":"F.","email":"","affiliations":[],"preferred":false,"id":397877,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bluth, G.","contributorId":94822,"corporation":false,"usgs":true,"family":"Bluth","given":"G.","email":"","affiliations":[],"preferred":false,"id":397881,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Rose, B.","contributorId":68500,"corporation":false,"usgs":true,"family":"Rose","given":"B.","email":"","affiliations":[],"preferred":false,"id":397880,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Schneider, D.","contributorId":52752,"corporation":false,"usgs":true,"family":"Schneider","given":"D.","email":"","affiliations":[],"preferred":false,"id":397878,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Tupper, A.","contributorId":58056,"corporation":false,"usgs":false,"family":"Tupper","given":"A.","email":"","affiliations":[{"id":32858,"text":"Australian Bureau of Meteorology","active":true,"usgs":false}],"preferred":false,"id":397879,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70023546,"text":"70023546 - 2001 - A comparison of solute-transport solution techniques and their effect on sensitivity analysis and inverse modeling results","interactions":[],"lastModifiedDate":"2022-10-17T15:21:48.913436","indexId":"70023546","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1861,"text":"Ground Water","active":true,"publicationSubtype":{"id":10}},"title":"A comparison of solute-transport solution techniques and their effect on sensitivity analysis and inverse modeling results","docAbstract":"Five common numerical techniques for solving the advection-dispersion equation (finite difference, predictor corrector, total variation diminishing, method of characteristics, and modified method of characteristics) were tested using simulations of a controlled conservative tracer-test experiment through a heterogeneous, two-dimensional sand tank. The experimental facility was constructed using discrete, randomly distributed, homogeneous blocks of five sand types. This experimental model provides an opportunity to compare the solution techniques: the heterogeneous hydraulic-conductivity distribution of known structure can be accurately represented by a numerical model, and detailed measurements can be compared with simulated concentrations and total flow through the tank. The present work uses this opportunity to investigate how three common types of results - simulated breakthrough curves, sensitivity analysis, and calibrated parameter values - change in this heterogeneous situation given the different methods of simulating solute transport. The breakthrough curves show that simulated peak concentrations, even at very fine grid spacings, varied between the techniques because of different amounts of numerical dispersion. Sensitivity-analysis results revealed: (1) a high correlation between hydraulic conductivity and porosity given the concentration and flow observations used, so that both could not be estimated; and (2) that the breakthrough curve data did not provide enough information to estimate individual values of dispersivity for the five sands. This study demonstrates that the choice of assigned dispersivity and the amount of numerical dispersion present in the solution technique influence estimated hydraulic conductivity values to a surprising degree.","language":"English","publisher":"National Groundwater Association","doi":"10.1111/j.1745-6584.2001.tb02312.x","issn":"0017467X","usgsCitation":"Mehl, S., and Hill, M.C., 2001, A comparison of solute-transport solution techniques and their effect on sensitivity analysis and inverse modeling results: Ground Water, v. 39, no. 2, p. 300-307, https://doi.org/10.1111/j.1745-6584.2001.tb02312.x.","productDescription":"8 p.","startPage":"300","endPage":"307","costCenters":[],"links":[{"id":232534,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"39","issue":"2","noUsgsAuthors":false,"publicationDate":"2005-12-13","publicationStatus":"PW","scienceBaseUri":"5059e375e4b0c8380cd46033","contributors":{"authors":[{"text":"Mehl, S.","contributorId":20114,"corporation":false,"usgs":true,"family":"Mehl","given":"S.","affiliations":[],"preferred":false,"id":397991,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hill, M. C.","contributorId":48993,"corporation":false,"usgs":true,"family":"Hill","given":"M.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":397992,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022780,"text":"70022780 - 2001 - A model for rotation and shape of Asteroid 9969 Braille from ground-based observations and images obtained during the deep space 1 (DS1) flyby","interactions":[],"lastModifiedDate":"2012-03-12T17:20:39","indexId":"70022780","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1963,"text":"Icarus","active":true,"publicationSubtype":{"id":10}},"title":"A model for rotation and shape of Asteroid 9969 Braille from ground-based observations and images obtained during the deep space 1 (DS1) flyby","docAbstract":"Image data from the DS1 encounter with Asteroid 9969 Braille and data from a coordinated ground-based photometric observing campaign are combined to study the physical properties of this small Mars crosser. From telescope data the object's brightness was found to vary by up to 0.5 mag from night to night, with the most probable synodic rotational period being 226.4 ?? 1.3 h (9.4 days) and a mean lightcurve magnitude R(1, ?? = 24??) = 17.04 ?? 0.10. During the flyby of the spacecraft, two frame images from a range of approximately 13,500 km and phase angle 82.4??, which impose strong constraints on size, shape, and albedo of the object, were obtained. Using telescope and flyby data in combination, the asteroid is estimated to have a size of 2.1 ?? 1 ?? 1 km3 and shown to have photometric properties similar to the asteroid 4 Vesta, notably a comparably high albedo. The high albedo supports the notion (L. Soderblom et al. 1999, Bull. Am. Astron. Soc. 31,) that Braille is of the V or Q taxonomic type. ?? 2001 Academic Press.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Icarus","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1006/icar.2001.6648","issn":"00191035","usgsCitation":"Oberst, J., Mottola, S., Di, M.M., Hicks, M., Buratti, B., Soderblom, L., and Thomas, N., 2001, A model for rotation and shape of Asteroid 9969 Braille from ground-based observations and images obtained during the deep space 1 (DS1) flyby: Icarus, v. 153, no. 1, p. 16-23, https://doi.org/10.1006/icar.2001.6648.","startPage":"16","endPage":"23","numberOfPages":"8","costCenters":[],"links":[{"id":233786,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":208214,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1006/icar.2001.6648"}],"volume":"153","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e46be4b0c8380cd46658","contributors":{"authors":[{"text":"Oberst, J.","contributorId":103427,"corporation":false,"usgs":true,"family":"Oberst","given":"J.","email":"","affiliations":[],"preferred":false,"id":394880,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Mottola, S.","contributorId":18124,"corporation":false,"usgs":true,"family":"Mottola","given":"S.","email":"","affiliations":[],"preferred":false,"id":394876,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Di, Martino M.","contributorId":16621,"corporation":false,"usgs":true,"family":"Di","given":"Martino","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":394875,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hicks, M.","contributorId":34563,"corporation":false,"usgs":true,"family":"Hicks","given":"M.","email":"","affiliations":[],"preferred":false,"id":394877,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Buratti, B.","contributorId":51433,"corporation":false,"usgs":true,"family":"Buratti","given":"B.","affiliations":[],"preferred":false,"id":394878,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Soderblom, L.","contributorId":106244,"corporation":false,"usgs":true,"family":"Soderblom","given":"L.","affiliations":[],"preferred":false,"id":394881,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Thomas, N.","contributorId":72490,"corporation":false,"usgs":true,"family":"Thomas","given":"N.","email":"","affiliations":[],"preferred":false,"id":394879,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":70023721,"text":"70023721 - 2001 - Groundwater residence times in Shenandoah National Park, Blue Ridge Mountains, Virginia, USA: A multi-tracer approach","interactions":[],"lastModifiedDate":"2018-12-03T09:11:42","indexId":"70023721","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1213,"text":"Chemical Geology","active":true,"publicationSubtype":{"id":10}},"title":"Groundwater residence times in Shenandoah National Park, Blue Ridge Mountains, Virginia, USA: A multi-tracer approach","docAbstract":"Chemical and isotopic properties of water discharging from springs and wells in Shenandoah National Park (SNP), near the crest of the Blue Ridge Mountains, VA, USA were monitored to obtain information on groundwater residence times. Investigated time scales included seasonal (wet season, April, 1996; dry season, August–September, 1997), monthly (March through September, 1999) and hourly (30-min interval recording of specific conductance and temperature, March, 1999 through February, 2000). Multiple environmental tracers, including tritium/helium-3 (3H/3He), chlorofluorocarbons (CFCs), sulfur hexafluoride (SF6), sulfur-35 (35S), and stable isotopes (δ18O and δ2H) of water, were used to estimate the residence times of shallow groundwater discharging from 34 springs and 15 wells. The most reliable ages of water from springs appear to be based on SF6 and 3H/3He, with most ages in the range of 0–3 years. This range is consistent with apparent ages estimated from concentrations of CFCs; however, CFC-based ages have large uncertainties owing to the post-1995 leveling-off of the CFC atmospheric growth curves. Somewhat higher apparent ages are indicated by 35S (>1.5 years) and seasonal variation of δ18O (mean residence time of 5 years) for spring discharge. The higher ages indicated by the 35S and δ18O data reflect travel times through the unsaturated zone and, in the case of 35S, possible sorption and exchange of S with soils or biomass. In springs sampled in April, 1996, apparent ages derived from the 3H/3He data (median age of 0.2 years) are lower than those obtained from SF6 (median age of 4.3 years), and in contrast to median ages from 3H/3He (0.3 years) and SF6 (0.7 years) obtained during the late summer dry season of 1997. Monthly samples from 1999 at four springs in SNP had SF6apparent ages of only 1.2 to 2.5±0.8 years, and were consistent with the 1997 SF6 data. Water from springs has low excess air (0–1 cm3 kg−1) and N2–Ar temperatures that vary seasonally. Concentrations of He and Ne in excess of solubility equilibrium indicate that the dissolved gases are not fractionated. The seasonal variations in N2–Ar temperatures suggest shallow, seasonal recharge, and the excess He and Ne data suggest waters mostly confined to gas exchange in the shallow, mountain-slope, water-table spring systems. Water from wells in the fractured rock contains up to 8 cm3 kg−1 of excess air with ages in the range of 0–25 years. Transient responses in specific conductance and temperature were observed in spring discharge within several hours of large precipitation events in September, 1999; both parameters increased initially, then decreased to values below pre-storm base-flow values. The groundwater residence times indicate that flushing rates of mobile atmospheric constituents through groundwater to streams draining the higher elevations in SNP average less than 3 years in base-flow conditions.
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L.","contributorId":86375,"corporation":false,"usgs":true,"family":"Michel","given":"R.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":398557,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Schlosser, P.","contributorId":106656,"corporation":false,"usgs":true,"family":"Schlosser","given":"P.","email":"","affiliations":[],"preferred":false,"id":398559,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70023545,"text":"70023545 - 2001 - Hydrogen bond breaking in aqueous solutions near the critical point","interactions":[],"lastModifiedDate":"2012-03-12T17:20:11","indexId":"70023545","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1216,"text":"Chemical Physics Letters","active":true,"publicationSubtype":{"id":10}},"title":"Hydrogen bond breaking in aqueous solutions near the critical point","docAbstract":"The nature of water-anion bonding is examined using X-ray absorption fine structure spectroscopy on a 1mZnBr2/6m NaBr aqueous solution, to near critical conditions. Analyses show that upon heating the solution from 25??C to 500??C, a 63% reduction of waters occurs in the solvation shell of ZnBr42-, which is the predominant complex at all pressure-temperature conditions investigated. A similar reduction in the hydration shell of waters in the Br- aqua ion was found. Our results indicate that the water-anion and water-water bond breaking mechanisms occurring at high temperatures are essentially the same. This is consistent with the hydration waters being weakly hydrogen bonded to halide anions in electrolyte solutions. ?? 2001 Elsevier Science B.V.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Chemical Physics Letters","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0009-2614(01)00061-6","issn":"00092614","usgsCitation":"Mayanovic, R.A., Anderson, A.J., Bassett, W.A., and Chou, I., 2001, Hydrogen bond breaking in aqueous solutions near the critical point: Chemical Physics Letters, v. 336, no. 3-4, p. 212-218, https://doi.org/10.1016/S0009-2614(01)00061-6.","startPage":"212","endPage":"218","numberOfPages":"7","costCenters":[],"links":[{"id":207518,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0009-2614(01)00061-6"},{"id":232533,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"336","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a3348e4b0c8380cd5ee9f","contributors":{"authors":[{"text":"Mayanovic, Robert A.","contributorId":88528,"corporation":false,"usgs":true,"family":"Mayanovic","given":"Robert","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":397990,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Anderson, Alan J.","contributorId":28770,"corporation":false,"usgs":true,"family":"Anderson","given":"Alan","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":397987,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bassett, William A.","contributorId":47533,"corporation":false,"usgs":true,"family":"Bassett","given":"William","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":397989,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Chou, I.-M. 0000-0001-5233-6479","orcid":"https://orcid.org/0000-0001-5233-6479","contributorId":44283,"corporation":false,"usgs":true,"family":"Chou","given":"I.-M.","affiliations":[{"id":245,"text":"Eastern Mineral and Environmental Resources Science Center","active":true,"usgs":true}],"preferred":false,"id":397988,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ]}