Carma A San Juan
Carma San Juan is a Physical Scientist with the Geology, Geophysics, and Geochemistry Science Center.
Science and Products
Filter Total Items: 14
Prospect- and Mine-Related Features from U.S. Geological Survey 7.5- and 15-Minute Topographic Quadrangle Maps for the Western United States
This data release has been updated in 2017 with a newer version that includes additional states.
It is recommended to use the updated data and map services of the new data release located at: https://doi.org/10.5066/F78W3CHG
These data are part of a larger USGS project to develop an updated geospatial database of mines, mineral deposits and mineral regions in the United States. Mine and prospect
Locatable Mineral Assessment Tracts for the U.S. Geological Survey Sagebrush Mineral Resource Assessment Project
The polygon (vector) feature class represents locatable mineral resource assessment tracts (tracts of land) associated with the Department of the Interior (DOI) Sagebrush Focal Areas in Montana, Wyoming and Utah, central Idaho, and the Oregon-Nevada-Idaho border area. The mineral resources tracts are geographic areas that were assessed by the U.S. Geological Survey (USGS) and were determined to be
Filter Total Items: 28
Critical tissue residue approach linking accumulated metals in aquatic insects to population and community-level effects
Whole body Zn concentrations in individuals (n = 825) from three aquatic insect taxa (mayflies Rhithrogena spp. and Drunella spp. and the caddisfly Arctopsyche grandis) were used to predict effects on populations and communities (n = 149 samples). Both mayflies accumulated significantly more Zn than the caddisfly. The presence/absence of Drunella spp. most reliably distinguished sites with low and
Authors
Travis S. Schmidt, William H. Clements, Robert E. Zuellig, Katharine A. Mitchell, Stan E. Church, Richard B. Wanty, Carma A. San Juan, Monique Adams, Paul J. Lamothe
Evaluation of the extent of contamination caused by historical mining in catchments of central Colorado
The U.S. Geological Survey conducted an assessment of stream water and sediment quality in central Colorado, an area of about 54,000 km2. The study area is focused on small tributary catchments in the Rocky Mountains. The Colorado Mineral belt, a northeast-trending mineralized zone that experienced base- and precious-metal mining at the beginning of the late 1800s and early 1900s, cuts diagonally
Authors
Stan E. Church, David L. Fey, Richard B. Wanty, Travis S. Schmidt, T. L. Klein, Barnaby W. Rockwell, Carma A. San Juan
Death Valley regional groundwater flow system, Nevada and California: Hydrogeologic framework and transient groundwater flow model
A numerical three-dimensional (3D) transient groundwater flow model of the Death Valley region was developed by the U.S. Geological Survey for the U.S. Department of Energy programs at the Nevada Test Site and at Yucca Mountain, Nevada. Decades of study of aspects of the groundwater flow system and previous less extensive groundwater flow models were incorporated and reevaluated together with new
Authors
Wayne Belcher, Frank A. D'Agnese, Grady M. O'Brien, Donald S. Sweetkind, Carma A. San Juan, Randell J. Laczniak, Christopher J. Potter, Heather Putnam, Claudia C. Faunt, Joan B. Blainey, Mary C. Hill, M. S. Bedinger, J. R. Harrill
Predicting risks to aquatic life based on lithologic specific geochemical baselines
No abstract available.
Authors
Travis S. Schmidt, R. B. Wanty, P. L. Verplanck, S. E. Church, C. San Juan, D. Fey, B.W. Rockwell, E.H. deWitt, T. L. Klein
Reconnaissance of weathering rates in alpine catchments of central Colorado, USA
No abstract available.
Authors
R.E. Wanty, P. L. Verplanck, C. Bern, T. Todoro, C. San Juan, E.H. deWitt, T. L. Klein, D. Fey, T.S. Schmidt, S. E. Church
Development of a new toxic-unit model for the bioassessment of metals in streams
Two toxic-unit models that estimate the toxicity of trace-metal mixtures to benthic communities were compared. The chronic criterion accumulation ratio (CCAR), a modification of biotic ligand model (BLM) outputs for use as a toxic-unit model, accounts for the modifying and competitive influences of major cations (Ca2+, Mg2+, Na+, K+, H+), anions (HCO3−, CO32−,SO42−, Cl−, S2−) and dissolved organic
Authors
Travis S. Schmidt, W.H. Clements, K.A. Mitchell, Stanley E. Church, Richard B. Wanty, David L. Fey, Philip L. Verplanck, Carma A. San Juan
Geochemistry of surface water in alpine catchments in central Colorado, USA: Resolving host-rock effects at different spatial scales
The US Geological Survey is conducting a study of surface-water quality in the Rocky Mountains of central Colorado, an area of approximately 55,000 km2. Using new and existing geologic maps, the more than 200 rock formations represented in the area were arranged into 17 groups based on lithologic similarity. The dominant regional geologic feature affecting water quality in central Colorado is the
Authors
R. B. Wanty, P. L. Verplanck, Juan C.A. San, S. E. Church, T.S. Schmidt, D. L. Fey, E.H. deWitt, T. L. Klein
Environmental effects of hydrothermal alteration and historical mining on water and sediment quality in Central Colorado
The U.S. Geological Survey conducted an environmental assessment of 198 catchments in a 54,000-km2 area of central Colorado, much of which is on Federal land. The Colorado Mineral Belt, a northeast-trending zone of historical base- and precious-metal mining, cuts diagonally across the study area. The investigation was intended to test the hypothesis that degraded water and sediment quality are res
Authors
S. E. Church, D. L. Fey, T. L. Klein, T.S. Schmidt, R. B. Wanty, E.H. deWitt, B.W. Rockwell, Juan C.A. San
Aquatic ecosystems in Central Colorado are influenced by mineral forming processes and historical mining
Stream water and sediment toxicity to aquatic insects were quantified from central Colorado catchments to distinguish the effect of geologic processes which result in high background metals concentrations from historical mining. Our sampling design targeted small catchments underlain by rocks of a single lithology, which allowed the development of biological and geochemical baselines without the c
Authors
T.S. Schmidt, S. E. Church, W.H. Clements, K.A. Mitchell, D. L. Fey, R. B. Wanty, P. L. Verplanck, Juan C.A. San, T. L. Klein, E.H. deWitt, B.W. Rockwell
Effects of Mining on the Environment - A National Overview
No abstract available.
Authors
S. E. Church, T.S. Schmidt, C. A. San Juan, G.S. Plumlee
Ground-water modeling of the Death Valley Region, Nevada and California
The Death Valley regional ground-water flow system (DVRFS) of southern Nevada and eastern California covers an area of about 100,000 square kilometers and contains very complex geology and hydrology. Using a computer model to represent the complex system, the U.S. Geological Survey simulated ground-water flow in the Death Valley region for use with U.S. Department of Energy projects in southern Ne
Authors
W.R. Belcher, C.C. Faunt, D. S. Sweetkind, J.B. Blainey, C. A. San Juan, R. J. Laczniak, M. C. Hill
Proceedings of the U.S. Geological Survey Fourth Biennial Geographic Information Science Workshop: Denver, Colorado, April 23-27, 2001
Introduction:
The U.S. Geological Survey (USGS) Fourth Biennial Geographic Information Science (GIS) Workshop (USGS-GIS 2001) was held April 23-27, 2001, at the Denver Federal Center in Denver, Colorado. The workshop provided an environment for participants to improve their knowledge about GIS and GIS-related applications that are used within the USGS. Two major topics of USGS-GIS 2001 were the
Authors
Jennifer B. Sieverling, Stephen J. Char, Carma A. San Juan
Science and Products
Filter Total Items: 14
Prospect- and Mine-Related Features from U.S. Geological Survey 7.5- and 15-Minute Topographic Quadrangle Maps for the Western United States
This data release has been updated in 2017 with a newer version that includes additional states.
It is recommended to use the updated data and map services of the new data release located at: https://doi.org/10.5066/F78W3CHG
These data are part of a larger USGS project to develop an updated geospatial database of mines, mineral deposits and mineral regions in the United States. Mine and prospect
Locatable Mineral Assessment Tracts for the U.S. Geological Survey Sagebrush Mineral Resource Assessment Project
The polygon (vector) feature class represents locatable mineral resource assessment tracts (tracts of land) associated with the Department of the Interior (DOI) Sagebrush Focal Areas in Montana, Wyoming and Utah, central Idaho, and the Oregon-Nevada-Idaho border area. The mineral resources tracts are geographic areas that were assessed by the U.S. Geological Survey (USGS) and were determined to be
Filter Total Items: 28
Critical tissue residue approach linking accumulated metals in aquatic insects to population and community-level effects
Whole body Zn concentrations in individuals (n = 825) from three aquatic insect taxa (mayflies Rhithrogena spp. and Drunella spp. and the caddisfly Arctopsyche grandis) were used to predict effects on populations and communities (n = 149 samples). Both mayflies accumulated significantly more Zn than the caddisfly. The presence/absence of Drunella spp. most reliably distinguished sites with low and
Authors
Travis S. Schmidt, William H. Clements, Robert E. Zuellig, Katharine A. Mitchell, Stan E. Church, Richard B. Wanty, Carma A. San Juan, Monique Adams, Paul J. Lamothe
Evaluation of the extent of contamination caused by historical mining in catchments of central Colorado
The U.S. Geological Survey conducted an assessment of stream water and sediment quality in central Colorado, an area of about 54,000 km2. The study area is focused on small tributary catchments in the Rocky Mountains. The Colorado Mineral belt, a northeast-trending mineralized zone that experienced base- and precious-metal mining at the beginning of the late 1800s and early 1900s, cuts diagonally
Authors
Stan E. Church, David L. Fey, Richard B. Wanty, Travis S. Schmidt, T. L. Klein, Barnaby W. Rockwell, Carma A. San Juan
Death Valley regional groundwater flow system, Nevada and California: Hydrogeologic framework and transient groundwater flow model
A numerical three-dimensional (3D) transient groundwater flow model of the Death Valley region was developed by the U.S. Geological Survey for the U.S. Department of Energy programs at the Nevada Test Site and at Yucca Mountain, Nevada. Decades of study of aspects of the groundwater flow system and previous less extensive groundwater flow models were incorporated and reevaluated together with new
Authors
Wayne Belcher, Frank A. D'Agnese, Grady M. O'Brien, Donald S. Sweetkind, Carma A. San Juan, Randell J. Laczniak, Christopher J. Potter, Heather Putnam, Claudia C. Faunt, Joan B. Blainey, Mary C. Hill, M. S. Bedinger, J. R. Harrill
Predicting risks to aquatic life based on lithologic specific geochemical baselines
No abstract available.
Authors
Travis S. Schmidt, R. B. Wanty, P. L. Verplanck, S. E. Church, C. San Juan, D. Fey, B.W. Rockwell, E.H. deWitt, T. L. Klein
Reconnaissance of weathering rates in alpine catchments of central Colorado, USA
No abstract available.
Authors
R.E. Wanty, P. L. Verplanck, C. Bern, T. Todoro, C. San Juan, E.H. deWitt, T. L. Klein, D. Fey, T.S. Schmidt, S. E. Church
Development of a new toxic-unit model for the bioassessment of metals in streams
Two toxic-unit models that estimate the toxicity of trace-metal mixtures to benthic communities were compared. The chronic criterion accumulation ratio (CCAR), a modification of biotic ligand model (BLM) outputs for use as a toxic-unit model, accounts for the modifying and competitive influences of major cations (Ca2+, Mg2+, Na+, K+, H+), anions (HCO3−, CO32−,SO42−, Cl−, S2−) and dissolved organic
Authors
Travis S. Schmidt, W.H. Clements, K.A. Mitchell, Stanley E. Church, Richard B. Wanty, David L. Fey, Philip L. Verplanck, Carma A. San Juan
Geochemistry of surface water in alpine catchments in central Colorado, USA: Resolving host-rock effects at different spatial scales
The US Geological Survey is conducting a study of surface-water quality in the Rocky Mountains of central Colorado, an area of approximately 55,000 km2. Using new and existing geologic maps, the more than 200 rock formations represented in the area were arranged into 17 groups based on lithologic similarity. The dominant regional geologic feature affecting water quality in central Colorado is the
Authors
R. B. Wanty, P. L. Verplanck, Juan C.A. San, S. E. Church, T.S. Schmidt, D. L. Fey, E.H. deWitt, T. L. Klein
Environmental effects of hydrothermal alteration and historical mining on water and sediment quality in Central Colorado
The U.S. Geological Survey conducted an environmental assessment of 198 catchments in a 54,000-km2 area of central Colorado, much of which is on Federal land. The Colorado Mineral Belt, a northeast-trending zone of historical base- and precious-metal mining, cuts diagonally across the study area. The investigation was intended to test the hypothesis that degraded water and sediment quality are res
Authors
S. E. Church, D. L. Fey, T. L. Klein, T.S. Schmidt, R. B. Wanty, E.H. deWitt, B.W. Rockwell, Juan C.A. San
Aquatic ecosystems in Central Colorado are influenced by mineral forming processes and historical mining
Stream water and sediment toxicity to aquatic insects were quantified from central Colorado catchments to distinguish the effect of geologic processes which result in high background metals concentrations from historical mining. Our sampling design targeted small catchments underlain by rocks of a single lithology, which allowed the development of biological and geochemical baselines without the c
Authors
T.S. Schmidt, S. E. Church, W.H. Clements, K.A. Mitchell, D. L. Fey, R. B. Wanty, P. L. Verplanck, Juan C.A. San, T. L. Klein, E.H. deWitt, B.W. Rockwell
Effects of Mining on the Environment - A National Overview
No abstract available.
Authors
S. E. Church, T.S. Schmidt, C. A. San Juan, G.S. Plumlee
Ground-water modeling of the Death Valley Region, Nevada and California
The Death Valley regional ground-water flow system (DVRFS) of southern Nevada and eastern California covers an area of about 100,000 square kilometers and contains very complex geology and hydrology. Using a computer model to represent the complex system, the U.S. Geological Survey simulated ground-water flow in the Death Valley region for use with U.S. Department of Energy projects in southern Ne
Authors
W.R. Belcher, C.C. Faunt, D. S. Sweetkind, J.B. Blainey, C. A. San Juan, R. J. Laczniak, M. C. Hill
Proceedings of the U.S. Geological Survey Fourth Biennial Geographic Information Science Workshop: Denver, Colorado, April 23-27, 2001
Introduction:
The U.S. Geological Survey (USGS) Fourth Biennial Geographic Information Science (GIS) Workshop (USGS-GIS 2001) was held April 23-27, 2001, at the Denver Federal Center in Denver, Colorado. The workshop provided an environment for participants to improve their knowledge about GIS and GIS-related applications that are used within the USGS. Two major topics of USGS-GIS 2001 were the
Authors
Jennifer B. Sieverling, Stephen J. Char, Carma A. San Juan