Metal Transport in Mineralized Mountain Watersheds Completed
The central objective of this project is to develop a greater understanding of deep bedrock groundwater circulation and its contribution to surface water metal loads in mineralized mountain blocks composed of sedimentary rocks. This work is being performed in cooperation with Lawrence Berkeley National Laboratory as part of a broader research program aimed at understanding processes controlling the export of water, metals, carbon, and nitrogen from Rocky Mountain headwater catchments under changing climate and land-use conditions.
Science Issue and Relevance
Understanding the manner in which hydrothermally altered rocks containing abundant sulfide minerals ('mineralized rocks') naturally release metal-rich water to the environment in mountain watersheds is essential for managing surface water resources with locally mineralized mountain headwaters, such as the Colorado River. Understanding how these sulfide weathering processes are influenced by changing climate and land-use conditions is particularly important for managing to protect future water quality and ecosystem health, and for establishing reasonable clean-up standards at active and abandoned mine sites in light of potentially changing background metal levels. Most studies of the environmental effects of sulfide weathering in mineralized watersheds are limited to sampling surface waters and springs because groundwater wells are not available. For this reason, our understanding of the deeper (>10s of meters) hydrogeology and geochemistry is severely limited. This study and its combined use of geophysical methods, geologic characterization, water chemistry data, and bedrock wells of varying depth (up to 250 feet) will address multiple fundamental, yet poorly studied, aspects of deep bedrock groundwater flow and metals transport in mineralized mountain blocks. Even though bedrock groundwater discharge may be a relatively small component of the annual surface water budget, its contribution to stream metal loads may be disproportionately large due to higher concentrations in this groundwater. This phenomenon has been understudied, and recent work suggests that it may be widely under-appreciated.
Methods to Address Issue
This project combines geophysical, hydrologic, and geochemical methods with geological and borehole data to accomplish the research objectives. Our interdisciplinary approach is necessitated by the inherent complexity of hydrogeochemical systems in mineralized mountain blocks. Work will be focused in Redwell Basin, a road-accessed (allowing drilling) alpine watershed near Crested Butte, Colorado containing extensive mineralized bedrock. Redwell basin overlies the unmined but well-delineated Mt. Emmons porphyry Mo deposit (one of the largest in the USA), produces both natural and mining-related acid-rock drainage, and is within the upper East River watershed where most research activities funded under Lawrence Berkeley National Laboratory Watershed Function Science Focus Area are occurring. Two deep boreholes will be drilled in the upper part of Redwell Basin and completed with multi-level monitoring wells to depths up to 250 feet. Multiple shallow piezometers will also be drilled and installed in groundwater discharge zones. These wells and piezometers will provide a window to the deeper groundwater system, and enable the collection of geologic, geophysical, hydraulic, and geochemical data that will be used in combination with numerical modeling to determine fluxes of groundwater and dissolved constituents through the bedrock. Geophysical surveys will be used to generalize spatially discrete borehole and outcrop observations over broader areas. This integrated research approach should help fill significant knowledge gaps regarding the hydrogeochemical significance of bedrock flow systems for shallow ecosystems in the upper East River area, and the effects of mineralization on the hydraulic properties of the rocks.
Below are data releases associated with this project.
Surface electrical resistivity tomography, magnetic, and gravity surveys in Redwell Basin and the greater East River watershed near Crested Butte, Colorado, 2017
Strontium isotopic data from the Mount Emmons-Redwell area, Crested Butte, Colorado
Whole rock major, minor, and trace element geochemistry of the upper part of the Mount Emmons-Redwell porphyry molybdenum (Climax-type) deposit, Redwell Basin, Crested Butte, Colorado
Airborne electromagnetic, magnetic, and radiometric survey, upper East River and surrounding watersheds near Crested Butte, Colorado, 2017
Hydrologic and geophysical data from high-elevation boreholes in Redwell Basin near Crested Butte, Colorado
Geochemical analyses of surface water, groundwater and springs surrounding Mount Emmons near Crested Butte, Colorado (ver. 2.0, September 2020)
Environmental tracer data from surface water and groundwater samples collected in Redwell Basin near Crested Butte, Colorado, 2017-2019
Below are publications associated with this project.
Mineralogical, magnetic and geochemical data constrain the pathways and extent of weathering of mineralized sedimentary rocks
Surface parameters and bedrock properties covary across a mountainous watershed: Insights from machine learning and geophysics
Direct observation of the depth of active groundwater circulation in an alpine watershed
Baseflow age distributions and depth of active groundwater flow in a snow‐dominated mountain headwater basin
Mountain-block recharge: A review of current understanding
A 20-year record of water chemistry in an alpine setting, Mount Emmons, Colorado, USA
The suitability of using dissolved gases to determine groundwater discharge to high gradient streams
Below are news stories associated with this project.
Below are partners associated with this project.
- Overview
The central objective of this project is to develop a greater understanding of deep bedrock groundwater circulation and its contribution to surface water metal loads in mineralized mountain blocks composed of sedimentary rocks. This work is being performed in cooperation with Lawrence Berkeley National Laboratory as part of a broader research program aimed at understanding processes controlling the export of water, metals, carbon, and nitrogen from Rocky Mountain headwater catchments under changing climate and land-use conditions.
Science Issue and Relevance
Understanding the manner in which hydrothermally altered rocks containing abundant sulfide minerals ('mineralized rocks') naturally release metal-rich water to the environment in mountain watersheds is essential for managing surface water resources with locally mineralized mountain headwaters, such as the Colorado River. Understanding how these sulfide weathering processes are influenced by changing climate and land-use conditions is particularly important for managing to protect future water quality and ecosystem health, and for establishing reasonable clean-up standards at active and abandoned mine sites in light of potentially changing background metal levels. Most studies of the environmental effects of sulfide weathering in mineralized watersheds are limited to sampling surface waters and springs because groundwater wells are not available. For this reason, our understanding of the deeper (>10s of meters) hydrogeology and geochemistry is severely limited. This study and its combined use of geophysical methods, geologic characterization, water chemistry data, and bedrock wells of varying depth (up to 250 feet) will address multiple fundamental, yet poorly studied, aspects of deep bedrock groundwater flow and metals transport in mineralized mountain blocks. Even though bedrock groundwater discharge may be a relatively small component of the annual surface water budget, its contribution to stream metal loads may be disproportionately large due to higher concentrations in this groundwater. This phenomenon has been understudied, and recent work suggests that it may be widely under-appreciated.
Methods to Address Issue
This project combines geophysical, hydrologic, and geochemical methods with geological and borehole data to accomplish the research objectives. Our interdisciplinary approach is necessitated by the inherent complexity of hydrogeochemical systems in mineralized mountain blocks. Work will be focused in Redwell Basin, a road-accessed (allowing drilling) alpine watershed near Crested Butte, Colorado containing extensive mineralized bedrock. Redwell basin overlies the unmined but well-delineated Mt. Emmons porphyry Mo deposit (one of the largest in the USA), produces both natural and mining-related acid-rock drainage, and is within the upper East River watershed where most research activities funded under Lawrence Berkeley National Laboratory Watershed Function Science Focus Area are occurring. Two deep boreholes will be drilled in the upper part of Redwell Basin and completed with multi-level monitoring wells to depths up to 250 feet. Multiple shallow piezometers will also be drilled and installed in groundwater discharge zones. These wells and piezometers will provide a window to the deeper groundwater system, and enable the collection of geologic, geophysical, hydraulic, and geochemical data that will be used in combination with numerical modeling to determine fluxes of groundwater and dissolved constituents through the bedrock. Geophysical surveys will be used to generalize spatially discrete borehole and outcrop observations over broader areas. This integrated research approach should help fill significant knowledge gaps regarding the hydrogeochemical significance of bedrock flow systems for shallow ecosystems in the upper East River area, and the effects of mineralization on the hydraulic properties of the rocks.
- Data
Below are data releases associated with this project.
Surface electrical resistivity tomography, magnetic, and gravity surveys in Redwell Basin and the greater East River watershed near Crested Butte, Colorado, 2017
Surface electrical resistivity tomography (ERT), time-domain electromagnetics (TEM), nuclear magnetic resonance (NMR), magnetics, and gravity data were acquired in 2016, 2017 and 2018 in the greater East River Watershed near Crested Butte Colorado with a focused effort in Redwell Basin. Five ERT profiles were acquired within Redwell Basin and Brush Creek to map geologic structure at depths up to 4Strontium isotopic data from the Mount Emmons-Redwell area, Crested Butte, Colorado
This U.S. Geological Survey (USGS) data release contains strontium isotopic data from water and rock samples collected between 2000 and 2019 from the Mount Emmons area, central Colorado. The data include strontium isotopic compositions, 87Sr/86Sr, for surface- and groundwater samples collected from streams, springs, draining mines, piezometers, and drill holes and for leachates of rock samples colWhole rock major, minor, and trace element geochemistry of the upper part of the Mount Emmons-Redwell porphyry molybdenum (Climax-type) deposit, Redwell Basin, Crested Butte, Colorado
This U.S. Geological Survey (USGS) data release provides whole rock major, minor, and trace element geochemical data from the fluorine-rich Mount Emmons-Redwell porphyry molybdenum (Climax-type) deposit (Mt. Emmons-Redwell deposit), located approximately 5.6 km (3.5 mi) northwest of Crested Butte, Colorado. The Mt. Emmons-Redwell deposit partly underlies Redwell Basin on the northwest flank of MouAirborne electromagnetic, magnetic, and radiometric survey, upper East River and surrounding watersheds near Crested Butte, Colorado, 2017
This data release consists of 1,984 line-kilometers of airborne electromagnetic (AEM), magnetic data and radiometric data collected from October to November 2017 in the upper East River and surrounding watersheds in central Colorado. The U.S. Geological Survey contracted Geotech Ltd. to acquire these data as part of regional investigations into the geologic structure and hydrologic framework of thHydrologic and geophysical data from high-elevation boreholes in Redwell Basin near Crested Butte, Colorado
Four boreholes (MW1, MW1UZ, MW2, MW2.1) were drilled in the fall of 2017 and summer of 2018 in upper Redwell Basin, a headwater catchment underlain by hydrothermally altered sedimentary rock in the Elk Mountains near the town of Crested Butte, Colorado. The boreholes were continuously cored using a wireline HQ-sized coring system and sample a combination of Quaternary-aged surficial colluvium andGeochemical analyses of surface water, groundwater and springs surrounding Mount Emmons near Crested Butte, Colorado (ver. 2.0, September 2020)
The U.S. Geological Survey (USGS), Colorado Division of Reclamation, Mining and Safety (DRMS), and Coal Creek Watershed Coalition (CCWC) working independently, have intermittently collected samples of surface- and groundwater and springs around Mount Emmons, near Crested Butte, Colorado. This data release is a compilation of the comprehensive inorganic chemical analyses conducted as a result of thEnvironmental tracer data from surface water and groundwater samples collected in Redwell Basin near Crested Butte, Colorado, 2017-2019
This dataset contains environmental tracer data from surface water and groundwater samples collected by the U.S. Geological Survey in Redwell Basin, an alpine watershed in the Elk Mountains near the town of Crested Butte, Colorado. The basin is underlain by interbedded shale and sandstone that have been variably hydrothermally altered and silicified by local magmatic intrusions. Samples were colle - Publications
Below are publications associated with this project.
Mineralogical, magnetic and geochemical data constrain the pathways and extent of weathering of mineralized sedimentary rocks
The oxidative weathering of sulfidic rock can profoundly impact watersheds through the resulting export of acidity and metals. Weathering leaves a record of mineral transformation, particularly involving minor redox-sensitive phases, that can inform the development of conceptual and quantitative models. In sulfidic sedimentary rocks, however, variations in depositional history, diagenesis and mineAuthorsSergio Carrero, Sarah P. Slotznick, Sirine C. Fakra, M. Cole Sitar, Sharon E. Bone, Jeffrey L. Mauk, Andrew H. Manning, Nicholas L. Swanson-Hysell, Kenneth H. Williams, Jillian F. Banfield, Benjamin GilbertSurface parameters and bedrock properties covary across a mountainous watershed: Insights from machine learning and geophysics
Bedrock property quantification is critical for predicting the hydrological response of watersheds to climate disturbances. Estimating bedrock hydraulic properties over watershed scales is inherently difficult, particularly in fracture-dominated regions. Our analysis tests the covariability of above- and belowground features on a watershed scale, by linking borehole geophysical data, near-surfaceAuthorsSebastian Uhlemann, Baptiste Dafflon, Haruko Murakami Wainwright, Kenneth Hurst Williams, Burke J. Minsley, Katrina D. Zamudio, Bradley Carr, Nicola Falco, Craig Ulrich, Susan S. HubbardDirect observation of the depth of active groundwater circulation in an alpine watershed
The depth of active groundwater circulation is a fundamental control on stream flows and chemistry in mountain watersheds, yet it remains challenging to characterize and is rarely well constrained. We collected hydraulic conductivity, hydraulic head, temperature, chemical, noble gas, and 3H/3He groundwater age data from discrete levels in two boreholes 46 and 81 m deep in an alpine watershed, in cAuthorsAndrew H. Manning, Lyndsay B. Ball, Richard Wanty, Kenneth H. WilliamsBaseflow age distributions and depth of active groundwater flow in a snow‐dominated mountain headwater basin
Deeper flows through bedrock in mountain watersheds could be important, but lack of data to characterize bedrock properties limits understanding. To address data scarcity, we combine a previously published integrated hydrologic model of a snow‐dominated, headwater basin of the Colorado River with a new method for dating baseflow age using dissolved gas tracers SF6, CFC‐113, N2, and Ar. The originaAuthorsRosemary W.H. Carroll, Andrew H. Manning, Richard G. Niswonger, David W Marchetti, Kenneth H. WilliamsMountain-block recharge: A review of current understanding
Mountain-block recharge (MBR) is the subsurface inflow of groundwater to lowland aquifers from adjacent mountains. MBR can be a major component of recharge but remains difficult to characterize and quantify due to limited hydrogeologic, climatic, and other data in the mountain block and at the mountain front. The number of MBR-related studies has increased dramatically in the 15 years since the laAuthorsKatherine Markovich, Andrew H. Manning, Laura Condon, Jennifer McIntoshA 20-year record of water chemistry in an alpine setting, Mount Emmons, Colorado, USA
From 1997 to the present, the U.S. Geological Survey and other agencies have been collecting water samples for chemical analyses on Mount Emmons in central Colorado, USA. The geology of Mount Emmons is dominated by Upper Cretaceous to Paleogene sediments of marine to continental origin, with felsic intrusive rocks interrupting the sedimentary block. Extensive sulphide-rich alteration accompanied tAuthorsRichard Wanty, Andrew H. Manning, Michaela Johnson, Philip VerplanckThe suitability of using dissolved gases to determine groundwater discharge to high gradient streams
Determining groundwater discharge to streams using dissolved gases is known to be useful over a wide range of streamflow rates but the suitability of dissolved gas methods to determine discharge rates in high gradient mountain streams has not been sufficiently tested, even though headwater streams are critical as ecological habitats and water resources. The aim of this study is to test the suitabiAuthorsTom Gleeson, Andrew H. Manning, Andrea Popp, Mathew Zane, Jordan F. Clark - News
Below are news stories associated with this project.
- Partners
Below are partners associated with this project.