Andrew H Manning
Biography
B.A. Earth Science, Wesleyan University, Middletown, CT
M.S. Geology, with focus in structural geology, University of Utah, Salt Lake City
Ph.D. Geology, with focus in hydrogeology, University of Utah, Salt Lake City
Andrew Manning has been a Research Geologist with the U.S. Geological Survey since 2002. His research is largely focused on using noble gases and other environmental tracers to study mountain groundwater flow systems. His recent work focuses more specifically on the transport of metals in groundwater in mineralized mountain areas, and has expanded to include studying the source and migration of ore fluids responsible for the formation of mineral deposits.
Science and Products
Metal Transport in Mineralized Mountain Watersheds
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...
Geochemical Signatures of Covered Mineral Deposits in the Northern Midcontinent
We are evaluating the potential of geochemical prospecting techniques that have shown promise in other covered terranes for mineral exploration in the northern midcontinent of the U.S. Novel components will be added to these methods with the objective of method advancement and improving our understanding of processes controlling the transmission of unique geochemical signatures from buried...
Potential Impacts of Prospective Climate Change on Groundwater Recharge in the Western United States
Groundwater withdrawals in the western US are a critical component of the water resources strategy for the region. Climate change already may be substantially altering recharge into groundwater systems; however, the quantity and direction (increase or decrease) of changes are relatively unknown as most climate change assessments have focused on surface water systems. We propose to conduct a...
Using stream-side groundwater discharge for geochemical exploration in mountainous terrain
Groundwater chemistry has been predominantly used in geochemical exploration studies to identify mineralized targets concealed under transported cover in areas with gentle topography. Another potentially valuable ap-plication that has received little attention is using groundwater chemistry to identify deposits concealed within mountain ridges. A...
Manning, Andrew H.; Morrison, Jean M.; Wanty, Richard; Mills, Christopher T. Mountain-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...
Katherine Markovich; Manning, Andrew H.; Laura Condon; Jennifer McIntosh A 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...
Wanty, Richard; Manning, Andrew H.; Johnson, Michaela; Verplanck, Philip Testing the potential role of brine reflux in the formation of sedimentary exhalative (Sedex) ore deposits
Sedimentary exhalative (sedex) ore deposits are the world’s largest Zn-Pb deposits. While the geologic processes that formed these deposits are generally well understood, the fundamental hydrologic processes that drove these massive hydrothermal systems remain an area of debate. We use numerical modeling to test an emerging hypothesis, supported...
Manning, Andrew H.; Emsbo, Poul The 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...
Gleeson, Tom; Manning, Andrew H.; Popp, Andrea; Zane, Mathew; Clark, Jordan F. Noble gas data from Goldfield and Tonopah epithermal Au-Ag deposits, ancestral Cascades Arc, USA: Evidence for a primitive mantle volatile source
The He, Ne, and Ar isotopic composition of fluid inclusions in ore and gangue minerals were analyzed to determine the source of volatiles in the high-grade Goldfield and Tonopah epithermal Au-Ag deposits in southwestern Nevada, USA. Ar and Ne are mainly atmospheric, whereas He has only a minor atmospheric component. Corrected 3He/4He ratios (...
Manning, Andrew H.; Hofstra, Albert H. Implications of projected climate change for groundwater recharge in the western United States
Existing studies on the impacts of climate change on groundwater recharge are either global or basin/location-specific. The global studies lack the specificity to inform decision making, while the local studies do little to clarify potential changes over large regions (major river basins, states, or groups of states), a scale often important in...
Meixner, Thomas; Manning, Andrew H.; Stonestrom, David A.; Allen, Diana M.; Ajami, Hoori; Blasch, Kyle W.; Brookfield, Andrea E.; Castro, Christopher L.; Clark, Jordan F.; Gochis, David; Flint, Alan L.; Neff, Kirstin L.; Niraula, Rewati; Rodell, Matthew; Scanlon, Bridget R.; Singha, Kamini; Walvoord, Michelle Ann Insights into controls on hexavalent chromium in groundwater provided by environmental tracers, Sacramento Valley, California, USA
Environmental tracers are useful for determining groundwater age and recharge source, yet their application in studies of geogenic Cr(VI) in groundwater has been limited. Environmental tracer data from 166 wells located in the Sacramento Valley, northern California, were interpreted and compared to Cr concentrations to determine the origin and...
Manning, Andrew H.; Mills, Christopher T.; Morrison, Jean M.; Ball, Lyndsay B. Using noble gas tracers to constrain a groundwater flow model with recharge elevations: A novel approach for mountainous terrain
Environmental tracers provide information on groundwater age, recharge conditions, and flow processes which can be helpful for evaluating groundwater sustainability and vulnerability. Dissolved noble gas data have proven particularly useful in mountainous terrain because they can be used to determine recharge elevation. However, tracer-derived...
Doyle, Jessica M.; Gleeson, Tom; Manning, Andrew H.; Mayer, K. Ulrich Links between climate change, water-table depth, and water chemistry in a mineralized mountain watershed
Recent studies suggest that climate change is causing rising solute concentrations in mountain lakes and streams. These changes may be more pronounced in mineralized watersheds due to the sensitivity of sulfide weathering to changes in subsurface oxygen transport. Specific causal mechanisms linking climate change and accelerated weathering rates...
Manning, Andrew H.; Verplanck, Philip L.; Caine, Jonathan S.; Todd, Andrew S. Using geochemistry to identify the source of groundwater to Montezuma Well, a natural spring in Central Arizona, USA: Part 2
Montezuma Well is a unique natural spring located in a sinkhole surrounded by travertine. Montezuma Well is managed by the National Park Service, and groundwater development in the area is a potential threat to the water source for Montezuma Well. This research was undertaken to better understand the sources of groundwater to Montezuma Well....
Johnson, Raymond H.; DeWitt, Ed; Wirt, Laurie; Manning, Andrew H.; Hunt, Andrew G. Climate-change-driven deterioration of water quality in a mineralized watershed
A unique 30-year streamwater chemistry data set from a mineralized alpine watershed with naturally acidic, metal-rich water displays dissolved concentrations of Zn and other metals of ecological concern increasing by 100–400% (400–2000 μg/L) during low-flow months, when metal concentrations are highest. SO4 and other major ions show similar...
Todd, Andrew; Manning, Andrew H.; Verplanck, Philip L.; Crouch, Caitlin; McKnight, Diane M.; Dunham, Ryan