Research Interests
Glaciation, geomorphology, and subglacial processes; Quaternary geomorphic responses to climate change investigated through geologic mapping in the Great Plains, Basin and Range Province, and Great Lakes regions; Quaternary geologic and geomorphic record of large river systems.
Professional Experience
1996-present: Research Geologist, USGS
1992-1996: Hydrologist, USGS
1984-1991: Geologist, university teaching and research as graduate student, USGS contract work
1978-1983: Geologist, mostly private sector, mineral exploration industry
Education and Certifications
1992: Ph.D., Glaciology and Geology, University of Colorado
1986: M.S., Quaternary Geology, Humboldt State University
1978: B.A., Geology, Dartmouth College
Affiliations and Memberships*
American Geophysical Union, since 1985
Geological Society of America, since 1985
International Glaciological Society, since 1993
American Quaternary Association, since 1986
Colorado Scientific Society, since 1996
Science and Products
Implementation plan of the National Cooperative Geologic Mapping Program strategy—Great Lakes (Central Lowland and Superior Upland Physiographic Provinces)
An evaluation of effects of groundwater exchange on nearshore habitats and water quality of western Lake Erie
Stratigraphy and depositional environments of the upper Pleistocene Chemehuevi Formation along the lower Colorado River
Project plan-Surficial geologic mapping and hydrogeologic framework studies in the Greater Platte River Basins (Central Great Plains) in support of ecosystem and climate change research
Age, distribution, and formation of late cenozoic paleovalleys of the lower Colorado River and their relation to river aggradation and degradation
Late pleistocene aggradation and degradation of the lower colorado river: Perspectives from the Cottonwood area and other reconnaissance below Boulder Canyon
Coastal groundwater/surface-water interactions: a Great Lakes case study
Long-term sand supply to Coachella Valley Fringe-toed Lizard Habitat in the Northern Coachella Valley, California
Digital Geologic Map of the Nevada Test Site and Vicinity, Nye, Lincoln, and Clark Counties, Nevada, and Inyo County, California
Task 1-Grand Traverse Bay Quaternary Geologic Mapping
Missouri River Corridor Geologic Mapping
Geologic map of the northern White Hills, Mohave County, Arizona
Surficial geologic map of the Evansville, Indiana, and Henderson, Kentucky, area
Geologic map of the Hidden Hills Ranch Quadrangle, Clark County, Nevada
Geologic and geophysical maps of the Las Vegas 30' x 60' quadrangle, Clark and Nye counties, Nevada, and Inyo County, California
Geologic map of the Mound Spring quadrangle, Nye and Clark Counties, Nevada, and Inyo County, California
Science and Products
- Publications
Filter Total Items: 14
Implementation plan of the National Cooperative Geologic Mapping Program strategy—Great Lakes (Central Lowland and Superior Upland Physiographic Provinces)
IntroductionThe U.S. Geological Survey (USGS) National Cooperative Geologic Mapping Program (NCGMP) has published a strategic plan entitled “Renewing the National Cooperative Geologic Mapping Program as the Nation’s Authoritative Source for Modern Geologic Knowledge”. This plan provides the following vision, mission, and goals for the program for the years 2020–30:Vision: create an integrated, thrAn evaluation of effects of groundwater exchange on nearshore habitats and water quality of western Lake Erie
Historically, the high potentiometric surface of groundwater in the Silurian/Devonian carbonate aquifer in Monroe County, MI resulted in discharge of highly mineralized, SO4-rich groundwater to the Lake Erie shoreline near both Erie State Game Area (ESGA) and Pointe Mouillee State Game Area (PMSGA). Recently, regional groundwater levels near PMSGA have been drawn down as much as 45 m below lake leStratigraphy and depositional environments of the upper Pleistocene Chemehuevi Formation along the lower Colorado River
The Chemehuevi Formation forms a conspicuous, widespread, and correlative set of nonmarine sediments lining the valleys of the Colorado River and several of its larger tributaries in the Basin and Range geologic province. These sediments have been examined by geologists since J. S. Newberry visited the region in 1857 and are widely cited in the geologic literature; however their origin remains unrProject plan-Surficial geologic mapping and hydrogeologic framework studies in the Greater Platte River Basins (Central Great Plains) in support of ecosystem and climate change research
The Greater Platte River Basin area spans a central part of the Midcontinent and Great Plains from the Rocky Mountains on the west to the Missouri River on the east, and is defined to include drainage areas of the Platte, Niobrara, and Republican Rivers, the Rainwater Basin, and other adjoining areas overlying the northern High Plains aquifer. The Greater Platte River Basin contains abundant surfiAge, distribution, and formation of late cenozoic paleovalleys of the lower Colorado River and their relation to river aggradation and degradation
Distinctive far-traveled fluvial sediment of the lower Colorado River fills 20 paleo-valleys now stranded by the river downstream of Grand Canyon as it crosses the Basin and Range Province. These sediments resulted from two or more aggradational epi sodes in Pliocene and Pleistocene times following initial incision during the early Pliocene. A review of the stratigraphic evidence of major swings iLate pleistocene aggradation and degradation of the lower colorado river: Perspectives from the Cottonwood area and other reconnaissance below Boulder Canyon
Where the lower Colorado River traverses the Basin and Range Province below the Grand Canyon, significant late Pleistocene aggradation and subsequent degrada tion of the river are indicated by luminescence, paleomagnetic, and U-series data and stratigraphy. Aggradational, finely bedded reddish mud, clay, and silt are underlain and overlain by cross-bedded to plane-bedded fine sand and silt. That sCoastal groundwater/surface-water interactions: a Great Lakes case study
Key similarities exist between marine and Great Lakes coastal environments. Water and nutrient fluxes across lakebeds in the Great Lakes are influenced by seiche and wind set-up and set-down, analogous to tidal influence in marine settings. Groundwater/surface-water interactions also commonly involve a saline-fresh water interface, although in the Great-Lakes cases, it is groundwater that is commoLong-term sand supply to Coachella Valley Fringe-toed Lizard Habitat in the Northern Coachella Valley, California
The Coachella Valley fringe-toed lizard (Uma inornata) is a federally listed threatened species that inhabits active sand dunes in the vicinity of Palm Springs, California. The Whitewater Floodplain and Willow Hole Reserves provide some of the primary remaining habitat for this species. The sediment-delivery system that creates these active sand dunes consists of fluvial depositional areas fed epiDigital Geologic Map of the Nevada Test Site and Vicinity, Nye, Lincoln, and Clark Counties, Nevada, and Inyo County, California
This digital geologic map of the Nevada Test Site (NTS) and vicinity, as well as its accompanying digital geophysical maps, are compiled at 1:100,000 scale. The map compilation presents new polygon (geologic map unit contacts), line (fault, fold axis, metamorphic isograd, dike, and caldera wall) and point (structural attitude) vector data for the NTS and vicinity, Nye, Lincoln, and Clark Counties, - Science
Task 1-Grand Traverse Bay Quaternary Geologic Mapping
The area encompassed by Task 1 includes the counties around Grand Traverse Bay in Michigan, with focus on Grand Traverse, Antrim, Charlevoix, and Emmet Counties. The primary objective of Task 1 is to produce a seamless, zoomable geologic framework map geodatabase in GeMS format that includes the following data: Quaternary surficial map units on the basis of new LiDAR data; Quaternary sediment...Missouri River Corridor Geologic Mapping
The priority area of mapping for this task is the reach spanned by the Missouri National Recreational River (MNRR), a unit of the National Park Service. MNRR comprises the congressionally designated reaches (2) of the Missouri River: the 59-mile reach below Gavins Point (GP) Dam, and the 39-mile reach above Lewis and Clark Lake (the reservoir held in by GP dam, which is the lowest of the 6 largest... - Maps
Geologic map of the northern White Hills, Mohave County, Arizona
IntroductionThe northern White Hills map area lies within the Kingman Uplift, a regional structural high in which Tertiary rocks lie directly on Proterozoic rocks as a result of Cretaceous orogenic uplift and erosional stripping of Paleozoic and Mesozoic strata. The Miocene Salt Spring Fault forms the major structural boundary in the map area. This low-angle normal fault separates a footwall (loweSurficial geologic map of the Evansville, Indiana, and Henderson, Kentucky, area
The geologic map of the Evansville, Indiana, and Henderson, Kentucky, area depicts and describes surficial deposits according to their origin and age. Unconsolidated alluvium and outwash fill the Ohio River bedrock valley and attain maximum thickness of 33-39 m under Diamond Island, Kentucky, and Griffith Slough, south of Newburgh, Indiana. The fill is chiefly unconsolidated, fine- to medium-grainGeologic map of the Hidden Hills Ranch Quadrangle, Clark County, Nevada
The prominent structural feature in the Pahrump Valley is the right-lateral Pahrump-Stewart Valley fault system (PSV) (Anderson and others, 1995b), which is the central segment of the State Line fault system as defined by Blakely and others (1998). The main trace of this fault system, as shown in figure 1A, strikes northwest along the California-Nevada state line through Pahrump and Stewart ValleyGeologic and geophysical maps of the Las Vegas 30' x 60' quadrangle, Clark and Nye counties, Nevada, and Inyo County, California
Las Vegas and Pahrump are two of the fastest growing cities in the US, and the shortage of water looms as among the greatest future problems for these cities. These new maps of the Las Vegas 30 x 60-minute quadrangle provide a geologic and geophysical framework and fundamental earth science database needed to address societal issues such as ground water supply and contamination, surface flood, laGeologic map of the Mound Spring quadrangle, Nye and Clark Counties, Nevada, and Inyo County, California
The Mound Spring quadrangle, the southwestern-most 7.5' quadrangle of the area of the Las Vegas 1:100,000-scale quadrangle, is entirely within the Pahrump Valley, spanning the Nevada/California State line. New geologic mapping of the predominantly Quaternary materials is combined with new studies of gravity and geochronology in this quadrangle. Eleven predominantly fine-grained units are delinea
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government