As a first step toward understanding the role of sedimentary structures in flow and transport through porous media, this work deterministically examines how small‐scale laboratory‐measured values of hydraulic conductivity relate to in situ values of simple, artificial structures in an intermediate‐scale (10 m long), two‐dimensional, heterogeneous, laboratory experiment. Results were judged based on how well simulations using measured values of hydraulic conductivities matched measured hydraulic heads, net flow, and transport through the tank. Discrepancies were investigated using sensitivity analysis and nonlinear regression estimates of the in situ hydraulic conductivity that produce the best fit to measured hydraulic heads and net flow. Permeameter and column experiments produced laboratory measurements of hydraulic conductivity for each of the sands used in the intermediate‐scale experiments. Despite explicit numerical representation of the heterogeneity the laboratory‐measured values underestimated net flow by 12–14% and were distinctly smaller than the regression‐estimated values. The significance of differences in measured hydraulic conductivity values was investigated by comparing variability of transport predictions using the different measurement methods to that produced by different realizations of the heterogeneous distribution. Results indicate that the variations in measured hydraulic conductivity were more important to transport than variations between realizations of the heterogeneous distribution of hydraulic conductivity.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2001WR000242","usgsCitation":"Barth, G.R., Hill, M.C., Illangasekare, T.H., and Rajaram, H., 2001, Predictive modeling of flow and transport in a two‐dimensional intermediate‐scale, heterogeneous porous medium: Water Resources Research, v. 37, no. 10, p. 2503-2512, https://doi.org/10.1029/2001WR000242.","productDescription":"10 p.","startPage":"2503","endPage":"2512","costCenters":[],"links":[{"id":478911,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2001wr000242","text":"Publisher Index Page"},{"id":233621,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"37","issue":"10","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a8201e4b0c8380cd7b849","contributors":{"authors":[{"text":"Barth, Gilbert R.","contributorId":15374,"corporation":false,"usgs":false,"family":"Barth","given":"Gilbert","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":396004,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"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":396007,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Illangasekare, Tissa H.","contributorId":194933,"corporation":false,"usgs":false,"family":"Illangasekare","given":"Tissa","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":396006,"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":396005,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70023066,"text":"70023066 - 2001 - Viscoelastic shear zone model of a strike-slip earthquake cycle","interactions":[],"lastModifiedDate":"2022-11-30T17:29:48.769129","indexId":"70023066","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2314,"text":"Journal of Geophysical Research B: Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"Viscoelastic shear zone model of a strike-slip earthquake cycle","docAbstract":"I examine the behavior of a two-dimensional (2-D) strike-slip fault system embedded in a 1-D elastic layer (schizosphere) overlying a uniform viscoelastic half-space (plastosphere) and within the boundaries of a finite width shear zone. The viscoelastic coupling model of Savage and Prescott [1978] considers the viscoelastic response of this system, in the absence of the shear zone boundaries, to an earthquake occurring within the upper elastic layer, steady slip beneath a prescribed depth, and the superposition of the responses of multiple earthquakes with characteristic slip occurring at regular intervals. So formulated, the viscoelastic coupling model predicts that sufficiently long after initiation of the system, (1) average fault-parallel velocity at any point is the average slip rate of that side of the fault and (2) far-field velocities equal the same constant rate. Because of the sensitivity to the mechanical properties of the schizosphere-plastosphere system (i.e., elastic layer thickness, plastosphere viscosity), this model has been used to infer such properties from measurements of interseismic velocity. Such inferences exploit the predicted behavior at a known time within the earthquake cycle. By modifying the viscoelastic coupling model to satisfy the additional constraint that the absolute velocity at prescribed shear zone boundaries is constant, I find that even though the time-averaged behavior remains the same, the spatiotemporal pattern of surface deformation (particularly its temporal variation within an earthquake cycle) is markedly different from that predicted by the conventional viscoelastic coupling model. These differences are magnified as plastosphere viscosity is reduced or as the recurrence interval of periodic earthquakes is lengthened. Application to the interseismic velocity field along the Mojave section of the San Andreas fault suggests that the region behaves mechanically like a ???600-km-wide shear zone accommodating 50 mm/yr fault-parallel motion distributed between the San Andreas fault system and Eastern California Shear Zone. Copyright 2001 by the American Geophysical Union.","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2001JB000342","issn":"01480227","usgsCitation":"Pollitz, F., 2001, Viscoelastic shear zone model of a strike-slip earthquake cycle: Journal of Geophysical Research B: Solid Earth, v. 106, no. B11, p. 26541-26560, https://doi.org/10.1029/2001JB000342.","productDescription":"20 p.","startPage":"26541","endPage":"26560","costCenters":[],"links":[{"id":233659,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","otherGeospatial":"Mojave Desert, San Andreas Fault","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -119.96815379209215,\n 34.48443294269454\n ],\n [\n -119.69349558896727,\n 34.38475956763793\n ],\n [\n -119.28700144834212,\n 34.15778760857671\n ],\n [\n -116.79310496396727,\n 33.692870080798244\n ],\n [\n -115.00233347959211,\n 32.74622590534098\n ],\n [\n -114.57386668271728,\n 33.81161930566759\n ],\n [\n -116.65028269834234,\n 35.57295474555886\n ],\n [\n -117.59510691709224,\n 35.653338449032404\n ],\n [\n -119.96815379209215,\n 34.48443294269454\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"106","issue":"B11","noUsgsAuthors":false,"publicationDate":"2001-11-10","publicationStatus":"PW","scienceBaseUri":"505bc284e4b08c986b32abb9","contributors":{"authors":[{"text":"Pollitz, F. F.","contributorId":108280,"corporation":false,"usgs":true,"family":"Pollitz","given":"F. F.","affiliations":[],"preferred":false,"id":396024,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70022794,"text":"70022794 - 2001 - Mississippi Valley-type lead-zinc deposits through geological time: Implications from recent age-dating research","interactions":[],"lastModifiedDate":"2012-03-12T17:20:04","indexId":"70022794","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2746,"text":"Mineralium Deposita","active":true,"publicationSubtype":{"id":10}},"title":"Mississippi Valley-type lead-zinc deposits through geological time: Implications from recent age-dating research","docAbstract":"Remarkable advances in age dating Mississippi Valley-type (MVT) lead-zinc deposits provide a new opportunity to understand how and where these deposits form in the Earth's crust. These dates are summarized and examined in a framework of global tectonics, paleogeography, fluid migration, and paleoclimate. Nineteen districts have been dated by paleomagnetic and/or radiometric methods. Of the districts that have both paleomagnetic and radiometric dates, only the Pine Point and East Tennessee districts have significant disagreements. This broad agreement between paleomagnetic and radiometric dates provides added confidence in the dating techniques used. The new dates confirm the direct connection between the genesis of MVT lead-zinc ores with global-scale tectonic events. The dates show that MVT deposits formed mainly during large contractional tectonic events at restricted times in the history of the Earth. Only the deposits in the Lennard Shelf of Australia and Nanisivik in Canada have dates that correspond to extensional tectonic events. The most important period for MVT genesis was the Devonian to Permian time, which corresponds to a series of intense tectonic events during the assimilation of Pangea. The second most important period for MVT genesis was Cretaceous to Tertiary time when microplate assimilation affected the western margin of North America and Africa-Eurasia. There is a notable paucity of MVT lead-zinc ore formation following the breakup of Rodinia and Pangea. Of the five MVT deposits hosted in Proterozoic rocks, only the Nanisivik deposit has been dated as Proterozoic. The contrast in abundance between SEDEX and MVT lead-zinc deposits in the Proterozoic questions the frequently suggested notion that the two types of ores share similar genetic paths. The ages of MVT deposits, when viewed with respect to the orogenic cycle in the adjacent orogen suggest that no single hydrologic model can be universally applied to the migration of the ore fluids. However, topographically driven models best explain most MVT districts. The migration of MVT ore fluids is not a natural consequence of basin evolution; rather, MVT districts formed mainly where platform carbonates had some hydrological connection to orogenic belts. There may be a connection between paleoclimate and the formation of some MVT deposits. This possible relationship is suggested by the dominance of evaporated seawater in fluid inclusions in MVT ores, by hydrological considerations that include the need for multiple-basin volumes of ore fluid to form most MVT districts, and the need for adequate precipitation to provide sufficient topographic head for topographically-driven fluid migration. Paleoclimatic conditions that lead to formation of evaporite conditions but yet have adequate precipitation to form large hydrological systems are most commonly present in low latitudes. For the MVT deposits and districts that have been dated, more than 75% of the combined metal produced are from deposits that have dates that correspond to assembly of Pangea in Devonian through Permian time. The exceptional endowment of Pangea and especially, North America with MVT lead-zinc deposits may be explained by the following: (1) Laurentia, which formed the core of North America, stayed in low latitudes during the Paleozoic, which allowed the development of vast carbonate platforms; (2) intense orogenic activity during the assembly of Pangea created ground preparation for many MVT districts through far-field deformation of the craton; (3) uplifted orogenic belts along Pangean suture zones established large-scale migration of basin fluids; and (4) the location of Pangea in low latitudes with paleoclimates with high evaporation rates led to the formation of brines by the evaporation of seawater and infiltration of these brines into deep basin aquifers during Pangean orogenic events.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Mineralium Deposita","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1007/s001260100208","issn":"00264598","usgsCitation":"Leach, D.L., Bradley, D., Lewchuk, M.T., Symons, D.T., De Marsily, G., and Brannon, J., 2001, Mississippi Valley-type lead-zinc deposits through geological time: Implications from recent age-dating research: Mineralium Deposita, v. 36, no. 8, p. 711-740, https://doi.org/10.1007/s001260100208.","startPage":"711","endPage":"740","numberOfPages":"30","costCenters":[],"links":[{"id":208061,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s001260100208"},{"id":233456,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"36","issue":"8","noUsgsAuthors":false,"publicationDate":"2014-03-01","publicationStatus":"PW","scienceBaseUri":"505a5b5ae4b0c8380cd6f4ef","contributors":{"authors":[{"text":"Leach, D. L.","contributorId":18758,"corporation":false,"usgs":true,"family":"Leach","given":"D.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":394935,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bradley, D.","contributorId":20087,"corporation":false,"usgs":true,"family":"Bradley","given":"D.","affiliations":[],"preferred":false,"id":394936,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lewchuk, Michael T.","contributorId":74890,"corporation":false,"usgs":true,"family":"Lewchuk","given":"Michael","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":394939,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Symons, David T. A.","contributorId":26824,"corporation":false,"usgs":true,"family":"Symons","given":"David","email":"","middleInitial":"T. A.","affiliations":[],"preferred":false,"id":394937,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"De Marsily, G.","contributorId":8262,"corporation":false,"usgs":true,"family":"De Marsily","given":"G.","email":"","affiliations":[],"preferred":false,"id":394934,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Brannon, J.","contributorId":33890,"corporation":false,"usgs":true,"family":"Brannon","given":"J.","email":"","affiliations":[],"preferred":false,"id":394938,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70022795,"text":"70022795 - 2001 - 1857 slip on the San Andreas fault Southeast of Cholame, California","interactions":[],"lastModifiedDate":"2012-03-12T17:20:04","indexId":"70022795","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1135,"text":"Bulletin of the Seismological Society of America","onlineIssn":"1943-3573","printIssn":"0037-1106","active":true,"publicationSubtype":{"id":10}},"title":"1857 slip on the San Andreas fault Southeast of Cholame, California","docAbstract":"Sieh and Jahns (1984) forecasted that the next moderate Parkfield earthquake might trigger a major earthquake along a fault segment greater than 30 km long southeast of Cholame. Their forecast assumed (1) the slip was 3-4 m in 1857 and characteristic of the segment; (2) a slip rate of 3.4 cm/yr; and (3) full strain release in earthquakes. This study represents an independent measurement of channel offsets, on 1:2400-scale low-sun aerial photographs and by field investigation, to estimate the amount of 1857 slip. Although rainfall is only moderate (30 cm/yr), few reliable offsets of less than 20 m persist here because cattle grazing and agricultural disking of soft sediments on the steep terrain greatly aggravate erosion. Reconstruction of offset geometry and size depends heavily on assumptions made about the post-1857 erosion. Most of the apparent 3- to 4-m offsets of Sieh and Jahns (1984) can also be measured as 2 to 3 m larger with equal or lower uncertainty. The four offsets judged as most reliable range between 5.4 and 6.7 m, and the 11 offsets of medium-high reliability average 5.8 ?? 0.3 m. Data are too sparse and ambiguous to resolve details of the 1857 slip for this segment but it is distinctly less than the 9 m of the Carrizo Plain and more than the 3-4 m previously estimated. Further trenching may refine some measurements, but probability calculations for a Cholame segment earthquake must allow for large observer-dependent uncertainty in the 1857 slip. Although the probability of an M ???7 Cholame event seems less than that suggested by a 3.5-m characteristic earthquake model, it remains among the highest in the state.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Bulletin of the Seismological Society of America","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1785/0120000043","issn":"00371106","usgsCitation":"Lienkaemper, J.J., 2001, 1857 slip on the San Andreas fault Southeast of Cholame, California: Bulletin of the Seismological Society of America, v. 91, no. 6, p. 1659-1672, https://doi.org/10.1785/0120000043.","startPage":"1659","endPage":"1672","numberOfPages":"14","costCenters":[],"links":[{"id":208080,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1785/0120000043"},{"id":233492,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"91","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e229e4b0c8380cd459e7","contributors":{"authors":[{"text":"Lienkaemper, J. J.","contributorId":71947,"corporation":false,"usgs":true,"family":"Lienkaemper","given":"J.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":394940,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70022727,"text":"70022727 - 2001 - Rehabilitation of gypsum-mined lands in the Indian desert","interactions":[],"lastModifiedDate":"2013-01-16T16:15:40","indexId":"70022727","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":905,"text":"Arid Soil Research and Rehabilitation","active":true,"publicationSubtype":{"id":10}},"title":"Rehabilitation of gypsum-mined lands in the Indian desert","docAbstract":"The economic importance of mining in the Indian Desert is second only to agriculture. Land disturbed by mining, however, has only recently been the focus of rehabilitation efforts. This research assesses the success of rehabilitation plans used to revegetate gypsum mine spoils within the environmental constraints of the north-west Indian hot-desert ecosystem. The rehabilitation plan first examined both mined and unmined areas and established assessments of existing vegetative cover and the quality of native soils and mine spoils. Tests were made on the effect of the use, and conservation, of available water through rainwater harvesting, amendment application (for physical and chemical spoil modification), plant establishment protocols, and the selection of appropriate germ plasm. Our results show that the resulting vegetative cover is capable of perpetuating itself under natural conditions while concurrently meeting the needs of farmers. Although the mine spoils are deficient in organic matter and phosphorus, they possess adequate amounts of all other nutrients. Total boron concentrations (>5.0 mg kg-1) in both the topsail and mine spoil indicate potentially phytotoxic conditions. Electrical conductance of mine spoil is 6-10 times higher than for topsail with a near-neutral pH. Populations of spoil fungi, Azotobactor, and nitrifying bacteria are low. The soil moisture storage in rainwater harvesting plots increased by 8% over the control and 48% over the unmined area. As a result of rehabilitation efforts, mine spoils show a steady buildup in organic carbon, and P and K due to the decomposition of farmyard manure and the contribution of nitrogen fixation by the established leguminous plant species. The rehabilitation protocol used at the site appears to have been successful. Following revegetation of the area with a mixture of trees, shrubs, and grasses, native implanted species have become established. Species diversity, measured in terms of species richness, increased after one year and then gradually declined over time; the decline was the result of the loss of annual species. The study not only develops methods of gypsum mine land rehabilitation but also helps in understanding processes of rehabilitation success in arid regions and emphasizes the importance of long-term monitoring of rehabilitation success. Copyright ?? 2001 Taylor & Francis.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Arid Soil Research and Rehabilitation","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1080/15324980119929","issn":"08903069","usgsCitation":"Sharma, K., Kumar, S., and Gough, L.P., 2001, Rehabilitation of gypsum-mined lands in the Indian desert: Arid Soil Research and Rehabilitation, v. 15, no. 1, p. 61-76, https://doi.org/10.1080/15324980119929.","startPage":"61","endPage":"76","numberOfPages":"16","costCenters":[],"links":[{"id":233487,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":265777,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1080/15324980119929"}],"volume":"15","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"50e4a601e4b0e8fec6cdc063","contributors":{"authors":[{"text":"Sharma, K.D.","contributorId":53545,"corporation":false,"usgs":true,"family":"Sharma","given":"K.D.","email":"","affiliations":[],"preferred":false,"id":394681,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kumar, S.","contributorId":89843,"corporation":false,"usgs":true,"family":"Kumar","given":"S.","affiliations":[],"preferred":false,"id":394683,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Gough, L. P.","contributorId":64198,"corporation":false,"usgs":true,"family":"Gough","given":"L.","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":394682,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70023040,"text":"70023040 - 2001 - River flow mass exponents with fractal channel networks and rainfall","interactions":[],"lastModifiedDate":"2012-03-12T17:20:36","indexId":"70023040","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":664,"text":"Advances in Water Resources","active":true,"publicationSubtype":{"id":10}},"title":"River flow mass exponents with fractal channel networks and rainfall","docAbstract":"An important problem in hydrologic science is understanding how river flow is influenced by rainfall properties and drainage basin characteristics. In this paper we consider one approach, the use of mass exponents, in examining the relation of river flow to rainfall and the channel network, which provides the primary conduit for transport of water to the outlet in a large basin. Mass exponents, which characterize the power-law behavior of moments as a function of scale, are ideally suited for defining scaling behavior of processes that exhibit a high degree of variability or intermittency. The main result in this paper is an expression relating the mass exponent of flow resulting from an instantaneous burst of rainfall to the mass exponents of spatial rainfall and that of the network width function. Spatial rainfall is modeled as a random multiplicative cascade and the channel network as a recursive replacement tree; these fractal models reproduce certain types of self-similar behavior seen in actual rainfall and networks. It is shown that under these modeling assumptions the scaling behavior of flow mirrors that of rainfall if rainfall is highly variable in space, and on the other hand flow mirrors the structure of the network if rainfall is not so highly variable. ?? 2001 Elsevier Science Ltd. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Advances in Water Resources","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0309-1708(01)00031-8","issn":"03091708","usgsCitation":"Troutman, B., and Over, T., 2001, River flow mass exponents with fractal channel networks and rainfall: Advances in Water Resources, v. 24, no. 9-10, p. 967-989, https://doi.org/10.1016/S0309-1708(01)00031-8.","startPage":"967","endPage":"989","numberOfPages":"23","costCenters":[],"links":[{"id":208222,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0309-1708(01)00031-8"},{"id":233805,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"24","issue":"9-10","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505aadaee4b0c8380cd86f56","contributors":{"authors":[{"text":"Troutman, B.M.","contributorId":73638,"corporation":false,"usgs":true,"family":"Troutman","given":"B.M.","email":"","affiliations":[],"preferred":false,"id":395907,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Over, T.M.","contributorId":35918,"corporation":false,"usgs":true,"family":"Over","given":"T.M.","email":"","affiliations":[],"preferred":false,"id":395906,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":1001770,"text":"1001770 - 2001 - Fuel model selection for BEHAVE in midwestern oak savannas","interactions":[],"lastModifiedDate":"2022-12-22T21:00:05.461597","indexId":"1001770","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2899,"text":"Northern Journal of Applied Forestry","active":true,"publicationSubtype":{"id":10}},"title":"Fuel model selection for BEHAVE in midwestern oak savannas","docAbstract":"BEHAVE, a fire behavior prediction system, can be a useful tool for managing areas with prescribed fire. However, the proper choice of fuel models can be critical in developing management scenarios. BEHAVE predictions were evaluated using four standardized fuel models that partially described oak savanna fuel conditions: Fuel Model 1 (Short Grass), 2 (Timber and Grass), 3 (Tall Grass), and 9 (Hardwood Litter). Although all four models yielded regressions with R2 in excess of 0.8, Fuel Model 2 produced the most reliable fire behavior predictions.
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\"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -92.10542395414957,\n 37.96672124077274\n ],\n [\n -92.10542395414957,\n 37.775679865928325\n ],\n [\n -91.75063142433156,\n 37.775679865928325\n ],\n [\n -91.75063142433156,\n 37.96672124077274\n ],\n [\n -92.10542395414957,\n 37.96672124077274\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"18","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b32e4b07f02db6b43bd","contributors":{"authors":[{"text":"Grabner, K.W.","contributorId":51237,"corporation":false,"usgs":true,"family":"Grabner","given":"K.W.","affiliations":[],"preferred":false,"id":311714,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Dwyer, J.P.","contributorId":58980,"corporation":false,"usgs":true,"family":"Dwyer","given":"J.P.","email":"","affiliations":[],"preferred":false,"id":311715,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Cutter, B.E.","contributorId":30935,"corporation":false,"usgs":true,"family":"Cutter","given":"B.E.","email":"","affiliations":[],"preferred":false,"id":311713,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":1013123,"text":"1013123 - 2001 - Cost considerations for long-term ecological monitoring","interactions":[],"lastModifiedDate":"2012-02-02T00:04:07","indexId":"1013123","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1456,"text":"Ecological Indicators","active":true,"publicationSubtype":{"id":10}},"title":"Cost considerations for long-term ecological monitoring","docAbstract":"For an ecological monitoring program to be successful over the long-term, the perceived benefits of the information must justify the cost. Financial limitations will always restrict the scope of a monitoring program, hence the program's focus must be carefully prioritized. Clearly identifying the costs and benefits of a program will assist in this prioritization process, but this is easier said than done. Frequently, the true costs of monitoring are not recognized and are, therefore, underestimated. Benefits are rarely evaluated, because they are difficult to quantify. The intent of this review is to assist the designers and managers of long-term ecological monitoring programs by providing a general framework for building and operating a cost-effective program. Previous considerations of monitoring costs have focused on sampling design optimization. We present cost considerations of monitoring in a broader context. We explore monitoring costs, including both budgetary costs--what dollars are spent on--and economic costs, which include opportunity costs. Often, the largest portion of a monitoring program budget is spent on data collection, and other, critical aspects of the program, such as scientific oversight, training, data management, quality assurance, and reporting, are neglected. Recognizing and budgeting for all program costs is therefore a key factor in a program's longevity. The close relationship between statistical issues and cost is discussed, highlighting the importance of sampling design, replication and power, and comparing the costs of alternative designs through pilot studies and simulation modeling. A monitoring program development process that includes explicit checkpoints for considering costs is presented. The first checkpoint occur during the setting of objectives and during sampling design optimization. The last checkpoint occurs once the basic shape of the program is known, and the costs and benefits, or alternatively the cost-effectiveness, of each program element can be evaluated. Moving into the implementation phase without careful evaluation of costs and benefits is risky because if costs are later found to exceed benefits, the program will fail. The costs of development, which can be quite high, will have been largely wasted. Realistic expectations of costs and benefits will help ensure that monitoring programs survive the early, turbulent stages of development and the challenges posed by fluctuating budgets during implementation.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Ecological Indicators","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","usgsCitation":"Caughlan, L., and Oakley, K., 2001, Cost considerations for long-term ecological monitoring: Ecological Indicators, v. 14, p. 1-12.","productDescription":"pp. 1-12","startPage":"1","endPage":"12","numberOfPages":"12","costCenters":[{"id":106,"text":"Alaska Biological Science Center","active":false,"usgs":true}],"links":[{"id":128482,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"14","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4ad5e4b07f02db683438","contributors":{"authors":[{"text":"Caughlan, L.","contributorId":38498,"corporation":false,"usgs":true,"family":"Caughlan","given":"L.","affiliations":[],"preferred":false,"id":318522,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Oakley, K.L.","contributorId":101592,"corporation":false,"usgs":true,"family":"Oakley","given":"K.L.","email":"","affiliations":[],"preferred":false,"id":318523,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":1013272,"text":"1013272 - 2001 - Polar bears in the Beaufort Sea: A 30-year mark-recapture case history","interactions":[],"lastModifiedDate":"2017-02-28T09:59:05","indexId":"1013272","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2151,"text":"Journal of Agricultural, Biological, and Environmental Statistics","active":true,"publicationSubtype":{"id":10}},"title":"Polar bears in the Beaufort Sea: A 30-year mark-recapture case history","docAbstract":"Knowledge of population size and trend is necessary to manage anthropogenic risks to polar bears (Ursus maritimus). Despite capturing over 1,025 females between 1967 and 1998, previously calculated estimates of the size of the southern Beaufort Sea (SBS) population have been unreliable. We improved estimates of numbers of polar bears by modeling heterogeneity in capture probability with covariates. Important covariates referred to the year of the study, age of the bear, capture effort, and geographic location. Our choice of best approximating model was based on the inverse relationship between variance in parameter estimates and likelihood of the fit and suggested a growth from ≈ 500 to over 1,000 females during this study. The mean coefficient of variation on estimates for the last decade of the study was 0.16—the smallest yet derived. A similar model selection approach is recommended for other projects where a best model is not identified by likelihood criteria alone.
","language":"English","publisher":"The International Biometric Society","doi":"10.1198/108571101750524562","usgsCitation":"Amstrup, S.C., McDonald, T.L., and Stirling, I., 2001, Polar bears in the Beaufort Sea: A 30-year mark-recapture case history: Journal of Agricultural, Biological, and Environmental Statistics, v. 6, no. 2, p. 221-234, https://doi.org/10.1198/108571101750524562.","productDescription":"14 p.","startPage":"221","endPage":"234","costCenters":[{"id":106,"text":"Alaska Biological Science Center","active":false,"usgs":true},{"id":114,"text":"Alaska Science Center","active":true,"usgs":true}],"links":[{"id":129549,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Canada, Russia, United States","otherGeospatial":"Beaufort Sea","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -185.18554687499997,\n 67.30597574414466\n ],\n [\n -128.408203125,\n 67.30597574414466\n ],\n [\n -128.408203125,\n 76.16399261609192\n ],\n [\n -185.18554687499997,\n 76.16399261609192\n ],\n [\n -185.18554687499997,\n 67.30597574414466\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"6","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4ad8e4b07f02db6849f1","contributors":{"authors":[{"text":"Amstrup, Steven C.","contributorId":67034,"corporation":false,"usgs":false,"family":"Amstrup","given":"Steven","email":"","middleInitial":"C.","affiliations":[{"id":13182,"text":"Polar Bears International","active":true,"usgs":false}],"preferred":false,"id":318558,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McDonald, T. L.","contributorId":101211,"corporation":false,"usgs":false,"family":"McDonald","given":"T.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":318559,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Stirling, I.","contributorId":103615,"corporation":false,"usgs":false,"family":"Stirling","given":"I.","email":"","affiliations":[],"preferred":false,"id":318560,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"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":70023236,"text":"70023236 - 2001 - Nitrogen input to the Gulf of Mexico","interactions":[],"lastModifiedDate":"2020-09-25T18:16:02.119947","indexId":"70023236","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Nitrogen input to the Gulf of Mexico","docAbstract":"Historical streamflow and concentration data were used in regression models to estimate the annual flux of nitrogen (N) to the Gulf of Mexico and to determine where the nitrogen originates within the Mississippi Basin. Results show that for 1980-1996 the mean annual total N flux to the Gulf of Mexico was 1 568 000 t yr-1. The flux was about 61% nitrate N, 37% organic N, and 2% ammonium N. The flux of nitrate N to the Gulf has approximately tripled in the last 30 years with most of the increase occurring between 1970 and 1983. The mean annual N flux has changed little since the early 1980s, but large year-to-year variations in N flux occur because of variations in precipitation. During wet years the N flux can increase by 50% or more due to flushing of nitrate N that has accumulated in the soils and unsaturated zones in the basin. The principal source areas of N are basins in southern Minnesota, Iowa, Illinois, Indiana, and Ohio that drain agricultural land. Basins in this region yield 1500 to more than 3100 kg N km-2 yr-1 to streams, several times the N yield of basins outside this region.","language":"English","publisher":"Wiley","doi":"10.2134/jeq2001.302329x","issn":"00472425","usgsCitation":"Goolsby, D.A., Battaglin, W., Aulenbach, B., and Hooper, R.P., 2001, Nitrogen input to the Gulf of Mexico, v. 30, no. 2, p. 329-336, https://doi.org/10.2134/jeq2001.302329x.","productDescription":"8 p.","startPage":"329","endPage":"336","numberOfPages":"8","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":232718,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","otherGeospatial":"Mississippi–Atchafalaya River basin","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -92.28515625,\n 46.255846818480315\n ],\n [\n -93.955078125,\n 46.98025235521883\n ],\n [\n -98.173828125,\n 48.3416461723746\n ],\n [\n -101.6015625,\n 48.22467264956519\n ],\n [\n -102.12890625,\n 46.01222384063236\n ],\n [\n -100.107421875,\n 42.94033923363181\n ],\n [\n -97.03125,\n 41.44272637767212\n ],\n [\n -94.306640625,\n 38.61687046392973\n ],\n [\n -93.515625,\n 34.45221847282654\n ],\n [\n -94.39453125,\n 30.221101852485987\n ],\n [\n -92.46093749999999,\n 28.844673680771795\n ],\n [\n -89.6484375,\n 28.844673680771795\n ],\n [\n -88.330078125,\n 30.14512718337613\n ],\n [\n -88.505859375,\n 34.23451236236987\n ],\n [\n -87.451171875,\n 39.57182223734374\n ],\n [\n -85.341796875,\n 39.30029918615029\n ],\n [\n -78.75,\n 39.57182223734374\n ],\n [\n -75.234375,\n 42.09822241118974\n ],\n [\n -75.41015624999999,\n 44.59046718130883\n ],\n [\n -79.1015625,\n 42.94033923363181\n ],\n [\n -82.6171875,\n 41.44272637767212\n ],\n [\n -87.5390625,\n 41.77131167976407\n ],\n [\n -89.296875,\n 43.644025847699496\n ],\n [\n -91.318359375,\n 45.9511496866914\n ],\n [\n -92.28515625,\n 46.255846818480315\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"30","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a66e2e4b0c8380cd73051","contributors":{"authors":[{"text":"Goolsby, D. 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P.","contributorId":26321,"corporation":false,"usgs":true,"family":"Hooper","given":"R.","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":396957,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70022966,"text":"70022966 - 2001 - Statistical self-similarity of width function maxima with implications to floods","interactions":[],"lastModifiedDate":"2012-03-12T17:20:40","indexId":"70022966","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":664,"text":"Advances in Water Resources","active":true,"publicationSubtype":{"id":10}},"title":"Statistical self-similarity of width function maxima with implications to floods","docAbstract":"Recently a new theory of random self-similar river networks, called the RSN model, was introduced to explain empirical observations regarding the scaling properties of distributions of various topologic and geometric variables in natural basins. The RSN model predicts that such variables exhibit statistical simple scaling, when indexed by Horton-Strahler order. The average side tributary structure of RSN networks also exhibits Tokunaga-type self-similarity which is widely observed in nature. We examine the scaling structure of distributions of the maximum of the width function for RSNs for nested, complete Strahler basins by performing ensemble simulations. The maximum of the width function exhibits distributional simple scaling, when indexed by Horton-Strahler order, for both RSNs and natural river networks extracted from digital elevation models (DEMs). We also test a powerlaw relationship between Horton ratios for the maximum of the width function and drainage areas. These results represent first steps in formulating a comprehensive physical statistical theory of floods at multiple space-time scales for RSNs as discrete hierarchical branching structures. ?? 2001 Published by Elsevier Science Ltd.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Advances in Water Resources","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0309-1708(01)00030-6","issn":"03091708","usgsCitation":"Veitzer, S., and Gupta, V., 2001, Statistical self-similarity of width function maxima with implications to floods: Advances in Water Resources, v. 24, no. 9-10, p. 955-965, https://doi.org/10.1016/S0309-1708(01)00030-6.","startPage":"955","endPage":"965","numberOfPages":"11","costCenters":[],"links":[{"id":208218,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0309-1708(01)00030-6"},{"id":233799,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"24","issue":"9-10","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b9744e4b08c986b31b9ad","contributors":{"authors":[{"text":"Veitzer, S.A.","contributorId":68931,"corporation":false,"usgs":true,"family":"Veitzer","given":"S.A.","email":"","affiliations":[],"preferred":false,"id":395639,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Gupta, V.K.","contributorId":35516,"corporation":false,"usgs":true,"family":"Gupta","given":"V.K.","email":"","affiliations":[],"preferred":false,"id":395638,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70023018,"text":"70023018 - 2001 - Association of amphibians with attenuation of ultraviolet-b radiation in montane ponds","interactions":[],"lastModifiedDate":"2017-11-21T13:55:50","indexId":"70023018","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2932,"text":"Oecologia","active":true,"publicationSubtype":{"id":10}},"title":"Association of amphibians with attenuation of ultraviolet-b radiation in montane ponds","docAbstract":"Ambient ultraviolet-b (UV-B) radiation (280–320 nm) has increased at north-temperate latitudes in the last two decades. UV-B can be detrimental to amphibians, and amphibians have shown declines in some areas during this same period. We documented the distribution of amphibians and salmonids in 42 remote, subalpine and alpine ponds in Olympic National Park, Washington, United States. We inferred relative exposure of amphibian habitats to UV-B by estimating the transmission of 305- and 320-nm radiation in pond water. We found breeding Ambystoma gracile, A. macrodactylum and Rana cascadae at 33%, 31%, and 45% of the study sites, respectively. Most R. cascadae bred in fishless shallow ponds with relatively low transmission of UV-B. The relationship with UV-B exposure remained marginally significant even after the presence of fish was included in the model. At 50 cm water depth, there was a 55% reduction in incident 305-nm radiation at sites where breeding populations of R. cascadae were detected compared to other sites. We did not detect associations between UV-B transmission and A. gracile or A. macrodactylum. Our field surveys do not provide evidence for decline of R. cascadae in Olympic National Park as has been documented in Northern California, but are consistent with the hypothesis that the spatial distribution of R. cascadae breeding sites is influenced by exposure to UV-B. Substrate or pond depth could also be related to the distribution of R. cascadae in Olympic National Park.
","language":"English","publisher":"Springer","doi":"10.1007/s004420100688","usgsCitation":"Adams, M.J., Schindler, D.E., and Bury, R.B., 2001, Association of amphibians with attenuation of ultraviolet-b radiation in montane ponds: Oecologia, v. 128, no. 4, p. 519-525, https://doi.org/10.1007/s004420100688.","productDescription":"7 p.","startPage":"519","endPage":"525","costCenters":[{"id":290,"text":"Forest and Rangeland Ecosystem Science Center","active":false,"usgs":true}],"links":[{"id":233401,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"128","issue":"4","noUsgsAuthors":false,"publicationDate":"2001-08-01","publicationStatus":"PW","scienceBaseUri":"5059ee90e4b0c8380cd49e16","contributors":{"authors":[{"text":"Adams, M. J. 0000-0001-8844-042X mjadams@usgs.gov","orcid":"https://orcid.org/0000-0001-8844-042X","contributorId":3133,"corporation":false,"usgs":false,"family":"Adams","given":"M.","email":"mjadams@usgs.gov","middleInitial":"J.","affiliations":[{"id":290,"text":"Forest and Rangeland Ecosystem Science Center","active":false,"usgs":true},{"id":200,"text":"Coop Res Unit Seattle","active":true,"usgs":true},{"id":289,"text":"Forest and Rangeland Ecosys Science Center","active":true,"usgs":true}],"preferred":true,"id":395819,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Schindler, Daniel E.","contributorId":83485,"corporation":false,"usgs":true,"family":"Schindler","given":"Daniel","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":395818,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bury, R. Bruce buryb@usgs.gov","contributorId":3660,"corporation":false,"usgs":true,"family":"Bury","given":"R.","email":"buryb@usgs.gov","middleInitial":"Bruce","affiliations":[{"id":290,"text":"Forest and Rangeland Ecosystem Science Center","active":false,"usgs":true}],"preferred":false,"id":395817,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70023246,"text":"70023246 - 2001 - Variations in creep rate along the Hayward Fault, California, interpreted as changes in depth of creep","interactions":[],"lastModifiedDate":"2012-03-12T17:20:04","indexId":"70023246","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":"Variations in creep rate along the Hayward Fault, California, interpreted as changes in depth of creep","docAbstract":"Variations ill surface creep rate along the Hayward fault are modeled as changes in locking depth using 3D boundary elements. Model creep is driven by screw dislocations at 12 km depth under the Hayward and other regional faults. Inferred depth to locking varies along strike from 4-12 km. (12 km implies no locking.) Our models require locked patches under the central Hayward fault, consistent with a M6.8 earthquake in 1868, but the geometry and extent of locking under the north and south ends depend critically on assumptions regarding continuity and creep behavior of the fault at its ends. For the northern onshore part of the fault, our models contain 1.4-1.7 times more stored moment than the model of Bu??rgmann et al. [2000]; 45-57% of this stored moment resides in creeping areas. It is important for seismic hazard estimation to know how much of this moment is released coseismically or as aseismic afterslip.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Geophysical Research Letters","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1029/2001GL012979","issn":"00948276","usgsCitation":"Simpson, R., Lienkaemper, J.J., and Galehouse, J., 2001, Variations in creep rate along the Hayward Fault, California, interpreted as changes in depth of creep: Geophysical Research Letters, v. 28, no. 11, p. 2269-2272, https://doi.org/10.1029/2001GL012979.","startPage":"2269","endPage":"2272","numberOfPages":"4","costCenters":[],"links":[{"id":478968,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2001gl012979","text":"Publisher Index Page"},{"id":207349,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1029/2001GL012979"},{"id":232238,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"28","issue":"11","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bc17be4b08c986b32a5c4","contributors":{"authors":[{"text":"Simpson, R.W.","contributorId":76738,"corporation":false,"usgs":true,"family":"Simpson","given":"R.W.","email":"","affiliations":[],"preferred":false,"id":397008,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lienkaemper, J. J.","contributorId":71947,"corporation":false,"usgs":true,"family":"Lienkaemper","given":"J.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":397007,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Galehouse, J.S.","contributorId":87720,"corporation":false,"usgs":true,"family":"Galehouse","given":"J.S.","affiliations":[],"preferred":false,"id":397009,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70024236,"text":"70024236 - 2001 - Determination of element affinities by density fractionation of bulk coal samples","interactions":[],"lastModifiedDate":"2012-03-12T17:20:16","indexId":"70024236","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1709,"text":"Fuel","active":true,"publicationSubtype":{"id":10}},"title":"Determination of element affinities by density fractionation of bulk coal samples","docAbstract":"A review has been made of the various methods of determining major and trace element affinities for different phases, both mineral and organic in coals, citing their various strengths and weaknesses. These include mathematical deconvolution of chemical analyses, direct microanalysis, sequential extraction procedures and density fractionation. A new methodology combining density fractionation with mathematical deconvolution of chemical analyses of whole coals and their density fractions has been evaluated. These coals formed part of the IEA-Coal Research project on the Modes of Occurrence of Trace Elements in Coal. Results were compared to a previously reported sequential extraction methodology and showed good agreement for most elements. For particular elements (Be, Mo, Cu, Se and REEs) in specific coals where disagreement was found, it was concluded that the occurrence of rare trace element bearing phases may account for the discrepancy, and modifications to the general procedure must be made to account for these.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Fuel","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier Science Ltd","publisherLocation":"Exeter, United Kingdom","doi":"10.1016/S0016-2361(00)00059-4","issn":"00162361","usgsCitation":"Querol, X., Klika, Z., Weiss, Z., Finkelman, R.B., Alastuey, A., Juan, R., Lopez-Soler, A., Plana, F., Kolker, A., and Chenery, S., 2001, Determination of element affinities by density fractionation of bulk coal samples: Fuel, v. 80, no. 1, p. 83-96, https://doi.org/10.1016/S0016-2361(00)00059-4.","startPage":"83","endPage":"96","numberOfPages":"14","costCenters":[],"links":[{"id":207084,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0016-2361(00)00059-4"},{"id":231687,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"80","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ffa3e4b0c8380cd4f2d4","contributors":{"authors":[{"text":"Querol, X.","contributorId":12340,"corporation":false,"usgs":true,"family":"Querol","given":"X.","email":"","affiliations":[],"preferred":false,"id":400492,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Klika, Z.","contributorId":69431,"corporation":false,"usgs":true,"family":"Klika","given":"Z.","email":"","affiliations":[],"preferred":false,"id":400497,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Weiss, Z.","contributorId":94562,"corporation":false,"usgs":true,"family":"Weiss","given":"Z.","email":"","affiliations":[],"preferred":false,"id":400499,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Finkelman, R. B.","contributorId":20341,"corporation":false,"usgs":true,"family":"Finkelman","given":"R.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":400493,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Alastuey, A.","contributorId":81375,"corporation":false,"usgs":true,"family":"Alastuey","given":"A.","email":"","affiliations":[],"preferred":false,"id":400498,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Juan, R.","contributorId":39663,"corporation":false,"usgs":true,"family":"Juan","given":"R.","email":"","affiliations":[],"preferred":false,"id":400494,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Lopez-Soler, A.","contributorId":65349,"corporation":false,"usgs":true,"family":"Lopez-Soler","given":"A.","email":"","affiliations":[],"preferred":false,"id":400496,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Plana, F.","contributorId":60799,"corporation":false,"usgs":true,"family":"Plana","given":"F.","email":"","affiliations":[],"preferred":false,"id":400495,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Kolker, A. 0000-0002-5768-4533","orcid":"https://orcid.org/0000-0002-5768-4533","contributorId":10947,"corporation":false,"usgs":true,"family":"Kolker","given":"A.","affiliations":[],"preferred":false,"id":400491,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Chenery, S.R.N.","contributorId":7579,"corporation":false,"usgs":true,"family":"Chenery","given":"S.R.N.","email":"","affiliations":[],"preferred":false,"id":400490,"contributorType":{"id":1,"text":"Authors"},"rank":10}]}} ,{"id":70023247,"text":"70023247 - 2001 - Remnant colloform pyrite at the haile gold deposit, South Carolina: A textural key to genesis","interactions":[],"lastModifiedDate":"2012-03-12T17:20:04","indexId":"70023247","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1472,"text":"Economic Geology","active":true,"publicationSubtype":{"id":10}},"title":"Remnant colloform pyrite at the haile gold deposit, South Carolina: A textural key to genesis","docAbstract":"Auriferous iron sulfide-bearing deposits of the Carolina slate belt have distinctive mineralogical and textural features-traits that provide a basis to construct models of ore deposition. Our identification of paragenetically early types of pyrite, especially remnant colloform, crustiform, and layered growth textures of pyrite containing electrum and pyrrhotite, establishes unequivocally that gold mineralization was coeval with deposition of host rocks and not solely related to Paleozoic tectonic events. Ore horizons at the Haile deposit, South Carolina, contain many remnants of early pyrite: (1) fine-grained cubic pyrite disseminated along bedding; (2) fine- grained spongy, rounded masses of pyrite that may envelop or drape over pyrite cubes; (3) fragments of botryoidally and crustiform layered pyrite, and (4) pyritic infilling of vesicles and pumice. Detailed mineral chemistry by petrography, microprobe, SEM, and EDS analysis of replaced pumice and colloform structures containing both arsenic compositional banding and electrum points to coeval deposition of gold and the volcanic host rocks and, thus, confirms a syngenetic origin for the gold deposits. Early pyrite textures are present in other major deposits of the Carolina slate belt, such as Ridgeway and Barite Hill, and these provide strong evidence for models whereby the sulfide ores formed prior to tectonism. The role of Paleozoic metamorphism was to remobilize and concentrate gold and other minerals in structurally prepared sites. Recognizing the significance of paragenetically early pyrite and gold textures can play an important role in distinguishing sulfide ores that form in volcanic and sedimentary environments from those formed solely by metamorphic processes. Exploration strategies applied to the Carolina slate belt and correlative rocks in the eastern United States in the Avalonian basement will benefit from using syngenetic models for gold mineralization.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Economic Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.2113/96.4.891","issn":"03610128","usgsCitation":"Foley, N., Ayuso, R., and Seal, R., 2001, Remnant colloform pyrite at the haile gold deposit, South Carolina: A textural key to genesis: Economic Geology, v. 96, no. 4, p. 891-902, https://doi.org/10.2113/96.4.891.","startPage":"891","endPage":"902","numberOfPages":"12","costCenters":[],"links":[{"id":207350,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.2113/96.4.891"},{"id":232239,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"96","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505aa6d7e4b0c8380cd850a4","contributors":{"authors":[{"text":"Foley, N.","contributorId":17800,"corporation":false,"usgs":true,"family":"Foley","given":"N.","email":"","affiliations":[],"preferred":false,"id":397010,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ayuso, R. A. 0000-0002-8496-9534","orcid":"https://orcid.org/0000-0002-8496-9534","contributorId":27079,"corporation":false,"usgs":true,"family":"Ayuso","given":"R. A.","affiliations":[],"preferred":false,"id":397011,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Seal, R.R. II","contributorId":102097,"corporation":false,"usgs":true,"family":"Seal","given":"R.R.","suffix":"II","email":"","affiliations":[],"preferred":false,"id":397012,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70023273,"text":"70023273 - 2001 - Comparision between crustal density and velocity variations in Southern California","interactions":[],"lastModifiedDate":"2012-03-12T17:20:13","indexId":"70023273","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":"Comparision between crustal density and velocity variations in Southern California","docAbstract":"We predict gravity from a three-dimensional Vp model of the upper crust and compare it to the observed isostatic residual gravity field. In general this comparison shows that the isostatic residual gravity field reflects the density variations in the upper to middle crust. Both data sets show similar density variations for the upper crust in areas such as the Peninsular Ranges and the Los Angeles basin. Both show similar variations across major faults, such as the San Andreas and Garlock faults in the Mojave Desert. The difference between the two data sets in regions such as the Salton Trough, the Eastern California Shear Zone, and the eastern Ventura basin (where depth to Moho is <30 km), however, suggests high-density middle to lower crust beneath these regions. Hence the joint interpretation of these data sets improves the depth constraints of crustal density variations.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Geophysical Research Letters","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1029/2001GL013392","issn":"00948276","usgsCitation":"Langenheim, V., and Hauksson, E., 2001, Comparision between crustal density and velocity variations in Southern California: Geophysical Research Letters, v. 28, no. 16, p. 3087-3090, https://doi.org/10.1029/2001GL013392.","startPage":"3087","endPage":"3090","numberOfPages":"4","costCenters":[],"links":[{"id":478934,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2001gl013392","text":"Publisher Index Page"},{"id":207596,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1029/2001GL013392"},{"id":232678,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"28","issue":"16","noUsgsAuthors":false,"publicationDate":"2001-08-15","publicationStatus":"PW","scienceBaseUri":"5059f83be4b0c8380cd4cf6e","contributors":{"authors":[{"text":"Langenheim, V.E. 0000-0003-2170-5213","orcid":"https://orcid.org/0000-0003-2170-5213","contributorId":54956,"corporation":false,"usgs":true,"family":"Langenheim","given":"V.E.","affiliations":[{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true}],"preferred":false,"id":397104,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hauksson, E.","contributorId":10932,"corporation":false,"usgs":true,"family":"Hauksson","given":"E.","affiliations":[],"preferred":false,"id":397103,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022971,"text":"70022971 - 2001 - Seismic-reflection imaging of Tertiary faulting and related post-Eocene deformation 20 km North of Memphis, Tennessee","interactions":[],"lastModifiedDate":"2012-03-12T17:20:39","indexId":"70022971","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1517,"text":"Engineering Geology","active":true,"publicationSubtype":{"id":10}},"title":"Seismic-reflection imaging of Tertiary faulting and related post-Eocene deformation 20 km North of Memphis, Tennessee","docAbstract":"Other than the Crittenden County fault zone (CCFZ), little is known about the seismic hazard from earthquake faults within 50 km of Memphis, Tennessee, a city that contains a large inventory of older buildings that are vulnerable to moderate and strong earthquake ground shaking. To address this lack of knowledge about faulting near Memphis, we acquired a 4.5 km long Mini-Sosie seismic-reflection profile across the boundary between the loess-covered bluffs and modern Mississippi River flood plain in Meeman-Shelby Forest State Park north of Memphis. We imaged a previously unknown reverse/thrust fault that displaces Paleozoic and Cretaceous rocks and upwarps Tertiary deposits on the floodplain portion of the profile about 25 km north of downtown Memphis. The Paleozoic and Cretaceous rocks are vertically faulted about 70 and 40 m, respectively, in an up-to-the-west sense of displacement. The fault displacement apparently terminates in the basal portion of the Paleocene section and causes only an upwarping of the overlying deposits. The overlying Paleocene and Eocene deposits, which are probably the youngest deposits imaged, are upwarped about 50-60 m with the same sense of displacement as the underlying older units. The sense of displacement, amplitude, and appearance of the fault in the seismic data are very similar to that observed in the seismic reflection images of the CCFZ 15 km west of this profile. Although we have imaged this new fault in only one location, its proximity to Memphis and similarities to the CCFZ, leads us to speculate that it may be a parallel structure to the CCFZ and thus warrants further study. ?? 2001 Elsevier Science B.V. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Engineering Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0013-7952(01)00052-7","issn":"00137952","usgsCitation":"Williams, R.A., Stephenson, W.J., Odum, J.K., and Worley, D.M., 2001, Seismic-reflection imaging of Tertiary faulting and related post-Eocene deformation 20 km North of Memphis, Tennessee: Engineering Geology, v. 62, no. 1-3, p. 79-90, https://doi.org/10.1016/S0013-7952(01)00052-7.","startPage":"79","endPage":"90","numberOfPages":"12","costCenters":[],"links":[{"id":208251,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0013-7952(01)00052-7"},{"id":233869,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"62","issue":"1-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8b81e4b08c986b3178a1","contributors":{"authors":[{"text":"Williams, R. A.","contributorId":82323,"corporation":false,"usgs":true,"family":"Williams","given":"R.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":395649,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Stephenson, W. J.","contributorId":87982,"corporation":false,"usgs":true,"family":"Stephenson","given":"W.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":395650,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Odum, J. K.","contributorId":105705,"corporation":false,"usgs":true,"family":"Odum","given":"J.","email":"","middleInitial":"K.","affiliations":[],"preferred":false,"id":395652,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Worley, D. M.","contributorId":98332,"corporation":false,"usgs":true,"family":"Worley","given":"D.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":395651,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70023119,"text":"70023119 - 2001 - Mountains on Io: High-resolution Galileo observations, initial interpretations, and formation models","interactions":[],"lastModifiedDate":"2022-12-01T17:37:05.095565","indexId":"70023119","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2317,"text":"Journal of Geophysical Research E: Planets","active":true,"publicationSubtype":{"id":10}},"title":"Mountains on Io: High-resolution Galileo observations, initial interpretations, and formation models","docAbstract":"During three close flybys in late 1999 and early 2000 the Galileo spacecraft acquired new observations of the mountains that tower above Io's surface. These images have revealed surprising variety in the mountains' morphologies. They range from jagged peaks several kilometers high to lower, rounded structures. Some are very smooth, others are covered by numerous parallel ridges. Many mountains have margins that are collapsing outward in large landslides or series of slump blocks, but a few have steep, scalloped scarps. From these observations we can gain insight into the structure and material properties of Io's crust as well as into the erosional processes acting on Io. We have also investigated formation mechanisms proposed for these structures using finite-element analysis. Mountain formation might be initiated by global compression due to the high rate of global subsidence associated with Io's high resurfacing rate; however, our models demonstrate that this hypothesis lacks a mechanism for isolating the mountains. The large fraction (∼40%) of mountains that are associated with paterae suggests that in some cases these features are tectonically related. Therefore we have also simulated the stresses induced in Io's crust by a combination of a thermal upwelling in the mantle with global lithospheric compression and have shown that this can focus compressional stresses. If this mechanism is responsible for some of Io's mountains, it could also explain the common association of mountains with paterae.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2000JE001354","issn":"01480227","usgsCitation":"Turtle, E.P., Jaeger, W.L., Keszthelyi, L., McEwen, A.S., Milazzo, M.P., Moore, J., Phillips, C.B., Radebaugh, J., Simonelli, D.P., Schuster, P., and Galileo SSI Team, 2001, Mountains on Io: High-resolution Galileo observations, initial interpretations, and formation models: Journal of Geophysical Research E: Planets, v. 106, no. E12, p. 33175-33199, https://doi.org/10.1029/2000JE001354.","productDescription":"25 p.","startPage":"33175","endPage":"33199","costCenters":[],"links":[{"id":233914,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"otherGeospatial":"Io","volume":"106","issue":"E12","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5ebbe4b0c8380cd70c3c","contributors":{"authors":[{"text":"Turtle, Elizabeth P.","contributorId":45443,"corporation":false,"usgs":false,"family":"Turtle","given":"Elizabeth","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":396277,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Jaeger, Windy L.","contributorId":61679,"corporation":false,"usgs":true,"family":"Jaeger","given":"Windy","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":396297,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Keszthelyi, Laszlo P. 0000-0003-1879-4331 laz@usgs.gov","orcid":"https://orcid.org/0000-0003-1879-4331","contributorId":52802,"corporation":false,"usgs":true,"family":"Keszthelyi","given":"Laszlo P.","email":"laz@usgs.gov","affiliations":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"preferred":true,"id":396231,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"McEwen, Alfred S.","contributorId":61657,"corporation":false,"usgs":false,"family":"McEwen","given":"Alfred","email":"","middleInitial":"S.","affiliations":[{"id":7042,"text":"University of Arizona","active":true,"usgs":false}],"preferred":false,"id":396232,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Milazzo, Moses P. 0000-0002-9101-2191 moses@usgs.gov","orcid":"https://orcid.org/0000-0002-9101-2191","contributorId":4811,"corporation":false,"usgs":true,"family":"Milazzo","given":"Moses","email":"moses@usgs.gov","middleInitial":"P.","affiliations":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"preferred":true,"id":396319,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Moore, Jeff","contributorId":49059,"corporation":false,"usgs":true,"family":"Moore","given":"Jeff","email":"","affiliations":[{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true}],"preferred":false,"id":396284,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Phillips, Cynthia B.","contributorId":210488,"corporation":false,"usgs":false,"family":"Phillips","given":"Cynthia","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":396365,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Radebaugh, Jani","contributorId":101792,"corporation":false,"usgs":true,"family":"Radebaugh","given":"Jani","email":"","affiliations":[],"preferred":false,"id":396260,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Simonelli, Damon P.","contributorId":210484,"corporation":false,"usgs":false,"family":"Simonelli","given":"Damon","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":396271,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Schuster, Peter","contributorId":61607,"corporation":false,"usgs":true,"family":"Schuster","given":"Peter","email":"","affiliations":[],"preferred":false,"id":396261,"contributorType":{"id":1,"text":"Authors"},"rank":10},{"text":"Galileo SSI Team","contributorId":299582,"corporation":true,"usgs":false,"organization":"Galileo SSI Team","id":858120,"contributorType":{"id":1,"text":"Authors"},"rank":11}]}} ,{"id":70022802,"text":"70022802 - 2001 - Modelling middle pliocene warm climates of the USA","interactions":[],"lastModifiedDate":"2012-03-12T17:20:09","indexId":"70022802","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2997,"text":"Palaeontologia Electronica","active":true,"publicationSubtype":{"id":10}},"title":"Modelling middle pliocene warm climates of the USA","docAbstract":"The middle Pliocene warm period represents a unique time slice in which to model and understand climatic processes operating under a warm climatic regime. Palaeoclimatic model simulations, focussed on the United States of America (USA), for the middle Pliocene (ca 3 Ma) were generated using the USGS PRISM2 2?? ?? 2?? data set of boundary conditions and the UK Meteorological Office's HadAMS General Circulation Model (GCM). Model results suggest that conditions in the USA during the middle Pliocene can be characterised as annually warmer (by 2?? to 4??C), less seasonal, wetter (by a maximum of 4 to 8 mm/day) and with an absence of freezing winters over the central and southern Great Plains. A sensitivity experiment suggests that the main forcing mechanisms for surface temperature changes in near coastal areas are the imposed Pliocene sea surface temperatures (SST's). In interior regions, reduced Northern Hemisphere terrestrial ice, combined with less snow cover and a reduction in the elevation of the western cordillera of North America, generate atmospheric circulation changes and positive albedo feedbacks that raise surface temperatures. A complex set of climatic feedback mechanisms cause an enhancement of the hydrological cycle magnifying the moisture bearing westerly wind belt during the winter season (Dec., Jan., Feb.). Predictions produced by the model are in broad agreement with available geological evidence. However, the GCM appears to underestimate precipitation levels in the interior and central regions of the southern USA. Copyright: Palaeontological Association, 22 June 2001.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Palaeontologia Electronica","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"10948074","usgsCitation":"Haywood, A., Valdes, P., Sellwood, B., Kaplan, J., and Dowsett, H., 2001, Modelling middle pliocene warm climates of the USA: Palaeontologia Electronica, v. 4, no. 1.","costCenters":[],"links":[{"id":233571,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"4","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5c6de4b0c8380cd6fcaf","contributors":{"authors":[{"text":"Haywood, A.M.","contributorId":101050,"corporation":false,"usgs":true,"family":"Haywood","given":"A.M.","email":"","affiliations":[],"preferred":false,"id":394954,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Valdes, P.J.","contributorId":77331,"corporation":false,"usgs":true,"family":"Valdes","given":"P.J.","email":"","affiliations":[],"preferred":false,"id":394950,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Sellwood, B.W.","contributorId":78509,"corporation":false,"usgs":true,"family":"Sellwood","given":"B.W.","email":"","affiliations":[],"preferred":false,"id":394951,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Kaplan, J.O.","contributorId":97288,"corporation":false,"usgs":true,"family":"Kaplan","given":"J.O.","email":"","affiliations":[],"preferred":false,"id":394953,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Dowsett, H.J. 0000-0003-1983-7524","orcid":"https://orcid.org/0000-0003-1983-7524","contributorId":87924,"corporation":false,"usgs":true,"family":"Dowsett","given":"H.J.","affiliations":[],"preferred":false,"id":394952,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70022990,"text":"70022990 - 2001 - Delineating a recharge area for a spring using numerical modeling, Monte Carlo techniques, and geochemical investigation","interactions":[],"lastModifiedDate":"2018-12-03T09:41:59","indexId":"70022990","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":"Delineating a recharge area for a spring using numerical modeling, Monte Carlo techniques, and geochemical investigation","docAbstract":"Recharge areas of spring systems can be hard to identify, but they can be critically important for protection of a spring resource. A recharge area for a spring complex in southern Wisconsin was delineated using a variety of complementary techniques. A telescopic mesh refinement (TMR) model was constructed from an existing regional-scale ground water flow model. This TMR model was formally optimized using parameter estimation techniques; the optimized \"best fit\" to measured heads and fluxes was obtained by using a horizontal hydraulic conductivity 200% larger than the original regional model for the upper bedrock aquifer and 80% smaller for the lower bedrock aquifer. The uncertainty in hydraulic conductivity was formally considered using a stochastic Monte Carlo approach. Two-hundred model runs used uniformly distributed, randomly sampled, horizontal hydraulic conductivity values within the range given by the TMR optimized values and the previously constructed regional model. A probability distribution of particles captured by the spring, or a \"probabilistic capture zone,\" was calculated from the realistic Monte Carlo results (136 runs of 200). In addition to portions of the local surface watershed, the capture zone encompassed areas outside of the watershed - demonstrating that the ground watershed and surface watershed do not coincide. Analysis of water collected from the site identified relatively large contrasts in chemistry, even for springs within 15 m of one another. The differences showed a distinct gradation from Ordovician-carbonate-dominated water in western spring vents to Cambrian-sandstone-influenced water in eastern spring vents. The difference in chemistry was attributed to distinctive bedrock geology as demonstrated by overlaying the capture zone derived from numerical modeling over a bedrock geology map for the area. This finding gives additional confidence to the capture zone calculated by modeling.","language":"English","publisher":"Wiley","doi":"10.1111/j.1745-6584.2001.tb02360.x","issn":"0017467X","usgsCitation":"Hunt, R.J., Steuer, J.J., Mansor, M., and Bullen, T., 2001, Delineating a recharge area for a spring using numerical modeling, Monte Carlo techniques, and geochemical investigation: Ground Water, v. 39, no. 5, p. 702-712, https://doi.org/10.1111/j.1745-6584.2001.tb02360.x.","productDescription":"11 p.","startPage":"702","endPage":"712","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":233582,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"39","issue":"5","noUsgsAuthors":false,"publicationDate":"2005-12-13","publicationStatus":"PW","scienceBaseUri":"5059fe60e4b0c8380cd4ece1","contributors":{"authors":[{"text":"Hunt, R. J.","contributorId":40164,"corporation":false,"usgs":true,"family":"Hunt","given":"R.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":395710,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Steuer, J. J.","contributorId":12430,"corporation":false,"usgs":true,"family":"Steuer","given":"J.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":395709,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Mansor, M.T.C.","contributorId":85370,"corporation":false,"usgs":true,"family":"Mansor","given":"M.T.C.","email":"","affiliations":[],"preferred":false,"id":395712,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Bullen, T.D.","contributorId":79911,"corporation":false,"usgs":true,"family":"Bullen","given":"T.D.","email":"","affiliations":[],"preferred":false,"id":395711,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70023499,"text":"70023499 - 2001 - Distribution of fine-scale mantle heterogeneity from observations of Pdiff coda","interactions":[],"lastModifiedDate":"2012-03-12T17:20:11","indexId":"70023499","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1135,"text":"Bulletin of the Seismological Society of America","onlineIssn":"1943-3573","printIssn":"0037-1106","active":true,"publicationSubtype":{"id":10}},"title":"Distribution of fine-scale mantle heterogeneity from observations of Pdiff coda","docAbstract":"We present stacked record sections of Global Seismic Network data that image the average amplitude and polarization of the high-frequency Pdiff coda and investigate their implications on the depth extent of fine-scale (~10 km) mantle heterogeneity. The extended 1-Hz coda lasts for at least 150 sec and is observed to a distance of 130??. The coda's polarization angle is about the same as the main Pdiff arrival (4.4 sec/deg) and is nearly constant with time. Previous studies show that multiple scattering from heterogeneity restricted to the lowermost mantle generates an extended Pdiff coda with a constant polarization. Here we present an alternative model that satisfies our Pdiff observations. The model consists of single scattering from weak (~1%) fine-scale (~2 km) structures distributed throughout the mantle. Although this model is nonunique, it demonstrates that Pdiff coda observations do not preclude the existence of scattering contributions from the entire mantle.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Bulletin of the Seismological Society of America","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1785/0120000285","issn":"00371106","usgsCitation":"Earle, P., and Shearer, P., 2001, Distribution of fine-scale mantle heterogeneity from observations of Pdiff coda: Bulletin of the Seismological Society of America, v. 91, no. 6, p. 1875-1881, https://doi.org/10.1785/0120000285.","startPage":"1875","endPage":"1881","numberOfPages":"7","costCenters":[],"links":[{"id":232490,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":207496,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1785/0120000285"}],"volume":"91","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a02cfe4b0c8380cd501f2","contributors":{"authors":[{"text":"Earle, P.S.","contributorId":17011,"corporation":false,"usgs":true,"family":"Earle","given":"P.S.","email":"","affiliations":[],"preferred":false,"id":397840,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Shearer, P.M.","contributorId":80456,"corporation":false,"usgs":true,"family":"Shearer","given":"P.M.","email":"","affiliations":[],"preferred":false,"id":397841,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70023510,"text":"70023510 - 2001 - Kullback-Leibler information in resolving natural resource conflicts when definitive data exist","interactions":[],"lastModifiedDate":"2012-03-12T17:20:10","indexId":"70023510","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3779,"text":"Wildlife Society Bulletin","onlineIssn":"1938-5463","printIssn":"0091-7648","active":true,"publicationSubtype":{"id":10}},"title":"Kullback-Leibler information in resolving natural resource conflicts when definitive data exist","docAbstract":"Conflicts often arise in the management of natural resources. Often they result from differing perceptions, varying interpretations of the law, and self-interests among stakeholder groups (for example, the values and perceptions about spotted owls and forest management differ markedly among environmental groups, government regulatory agencies, and timber industries). We extend the conceptual approach to conflict resolution of Anderson et al. (1999) by using information-theoretic methods to provide quantitative evidence for differing stakeholder positions. Importantly, we assume that relevant empirical data exist that are central to the potential resolution of the conflict. We present a hypothetical example involving an experiment to assess potential effects of a chemical on monthly survival probabilities of the hen clam (Spisula solidissima). The conflict centers on 3 stakeholder positions: 1) no effect, 2) an acute effect, and 3) an acute and chronic effect of the chemical treatment. Such data were given to 18 analytical teams to make independent analyses and provide the relative evidence for each of 3 stakeholder positions in the conflict. The empirical evidence strongly supports only one of the 3 positions in the conflict: the application of the chemical causes acute and chronic effects on monthly survival, following treatment. Formal inference from all the stakeholder positions is provided for the 2 key parameters underlying the hen clam controversy. The estimates of these parameters were essentially unbiased (the relative bias for the control and treatment group's survival probability was -0.857% and 1.400%, respectively) and precise (coefficients of variation were 0.576% and 2.761%, respectively). The advantages of making formal inference from all the models, rather than drawing conclusions from only the estimated best model, is illustrated. Finally, we contrast information-theoretic and Bayesian approaches in terms of how positions in the controversy enter the formal analysis.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Wildlife Society Bulletin","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"00917648","usgsCitation":"Anderson, D., Burnham, K., and White, G.C., 2001, Kullback-Leibler information in resolving natural resource conflicts when definitive data exist: Wildlife Society Bulletin, v. 29, no. 4, p. 1260-1270.","startPage":"1260","endPage":"1270","numberOfPages":"11","costCenters":[],"links":[{"id":232693,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"29","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a40cde4b0c8380cd65053","contributors":{"authors":[{"text":"Anderson, David R.","contributorId":8413,"corporation":false,"usgs":true,"family":"Anderson","given":"David R.","affiliations":[],"preferred":false,"id":397874,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Burnham, K.P.","contributorId":63760,"corporation":false,"usgs":true,"family":"Burnham","given":"K.P.","email":"","affiliations":[],"preferred":false,"id":397876,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"White, Gary C.","contributorId":26256,"corporation":false,"usgs":true,"family":"White","given":"Gary","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":397875,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70023432,"text":"70023432 - 2001 - 1r2dinv: A finite-difference model for inverse analysis of two dimensional linear or radial groundwater flow","interactions":[],"lastModifiedDate":"2012-03-12T17:20:14","indexId":"70023432","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1315,"text":"Computers & Geosciences","printIssn":"0098-3004","active":true,"publicationSubtype":{"id":10}},"title":"1r2dinv: A finite-difference model for inverse analysis of two dimensional linear or radial groundwater flow","docAbstract":"We have developed a program for inverse analysis of two-dimensional linear or radial groundwater flow problems. The program, 1r2dinv, uses standard finite difference techniques to solve the groundwater flow equation for a horizontal or vertical plane with heterogeneous properties. In radial mode, the program simulates flow to a well in a vertical plane, transforming the radial flow equation into an equivalent problem in Cartesian coordinates. The physical parameters in the model are horizontal or x-direction hydraulic conductivity, anisotropy ratio (vertical to horizontal conductivity in a vertical model, y-direction to x-direction in a horizontal model), and specific storage. The program allows the user to specify arbitrary and independent zonations of these three parameters and also to specify which zonal parameter values are known and which are unknown. The Levenberg-Marquardt algorithm is used to estimate parameters from observed head values. Particularly powerful features of the program are the ability to perform simultaneous analysis of heads from different tests and the inclusion of the wellbore in the radial mode. These capabilities allow the program to be used for analysis of suites of well tests, such as multilevel slug tests or pumping tests in a tomographic format. The combination of information from tests stressing different vertical levels in an aquifer provides the means for accurately estimating vertical variations in conductivity, a factor profoundly influencing contaminant transport in the subsurface. ?? 2001 Elsevier Science Ltd. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Computers and Geosciences","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0098-3004(01)00036-X","issn":"00983004","usgsCitation":"Bohling, G.C., and Butler, J., 2001, 1r2dinv: A finite-difference model for inverse analysis of two dimensional linear or radial groundwater flow: Computers & Geosciences, v. 27, no. 10, p. 1147-1156, https://doi.org/10.1016/S0098-3004(01)00036-X.","startPage":"1147","endPage":"1156","numberOfPages":"10","costCenters":[],"links":[{"id":232733,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":207624,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0098-3004(01)00036-X"}],"volume":"27","issue":"10","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e242e4b0c8380cd45a5d","contributors":{"authors":[{"text":"Bohling, Geoffrey C.","contributorId":43109,"corporation":false,"usgs":false,"family":"Bohling","given":"Geoffrey","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":397638,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Butler, J.J. Jr.","contributorId":12194,"corporation":false,"usgs":true,"family":"Butler","given":"J.J.","suffix":"Jr.","email":"","affiliations":[],"preferred":false,"id":397637,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022814,"text":"70022814 - 2001 - The Upper Pennsylvanian Pittsburgh coal bed: Resources and mine models","interactions":[],"lastModifiedDate":"2022-12-22T18:50:03.31214","indexId":"70022814","displayToPublicDate":"2001-01-01T00:00:00","publicationYear":"2001","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2832,"text":"Natural Resources Research","onlineIssn":"1573-8981","printIssn":"1520-7439","active":true,"publicationSubtype":{"id":10}},"title":"The Upper Pennsylvanian Pittsburgh coal bed: Resources and mine models","docAbstract":"The U.S. Geological Survey recently completed a digital coal resource assessment model of the Upper Pennsylvanian Pittsburgh coal bed, which indicates that after subtracting mined-out coal, 16 billion short tons (14 billion tonnes) remain of the original 34 billion short tons (31 billion tonnes) of coal. When technical, environmental, and social restrictions are applied to the remaining Pittsburgh coal model, only 12 billion short tons (11 billion tonnes) are available for mining. Our assessment models estimate that up to 0.61 billion short tons (0.55 billion tonnes), 2.7 billion short tons (2.4 billion tonnes), and 8.5 billion short tons (7.7 billion tonnes) could be available for surface mining, continuous mining, and longwall mining, respectively. This analysis is an example of a second-generation regional coal availability study designed to model recoverability characteristics for all the major coal beds in the United States.
","language":"English","publisher":"Springer","doi":"10.1023/A:1011529430807","issn":"15207439","usgsCitation":"Watson, W., Ruppert, L., Tewalt, S., and Bragg, L.J., 2001, The Upper Pennsylvanian Pittsburgh coal bed: Resources and mine models: Natural Resources Research, v. 10, no. 1, p. 21-34, https://doi.org/10.1023/A:1011529430807.","productDescription":"14 p.","startPage":"21","endPage":"34","costCenters":[],"links":[{"id":233789,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Maryland, Ohio, Pennsylvania, West Virginia","otherGeospatial":"Upper Pennsylvanian Pittsburgh Coal Bed","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -83.78929271159902,\n 39.066553580455945\n ],\n [\n -83.64647044597436,\n 38.81875203081822\n ],\n [\n -82.8774274772241,\n 38.85298303544727\n ],\n [\n -82.43797435222433,\n 38.54431172682851\n ],\n [\n -80.60325755534937,\n 37.69730870201133\n ],\n [\n -79.74632396159942,\n 38.58726238265223\n ],\n [\n -79.37278880534907,\n 38.707387597242956\n ],\n [\n -78.91136302409907,\n 38.91284766884306\n ],\n [\n -78.5378278678494,\n 39.34748007643097\n ],\n [\n -77.77977122722427,\n 39.89752847367427\n ],\n [\n -78.274155992849,\n 40.67690125274703\n ],\n [\n -78.74656810222416,\n 41.298869404839365\n ],\n [\n -80.26268138347442,\n 41.323626036386486\n ],\n [\n -81.3832868522241,\n 40.560151221702995\n ],\n [\n -83.28392161784913,\n 39.52566599169779\n ],\n [\n -83.78929271159902,\n 39.066553580455945\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"10","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bb153e4b08c986b3252cf","contributors":{"authors":[{"text":"Watson, W.D.","contributorId":96730,"corporation":false,"usgs":true,"family":"Watson","given":"W.D.","email":"","affiliations":[],"preferred":false,"id":394988,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ruppert, L.F. 0000-0003-4990-0539","orcid":"https://orcid.org/0000-0003-4990-0539","contributorId":59043,"corporation":false,"usgs":true,"family":"Ruppert","given":"L.F.","affiliations":[],"preferred":false,"id":394987,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Tewalt, S.J.","contributorId":55838,"corporation":false,"usgs":true,"family":"Tewalt","given":"S.J.","affiliations":[],"preferred":false,"id":394986,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Bragg, L. J.","contributorId":104055,"corporation":false,"usgs":true,"family":"Bragg","given":"L.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":394989,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ]}