Benjamin J Drenth, Ph.D.
Biography
Ben Drenth is a Research Geophysicist in the Geology, Geophysics, and Geochemistry Science Center in Denver, Colorado. His research is focused on the interpretation of gravity and magnetic geophysical data, in conjunction with other types of geophysical data and geologic information, to address 3D geologic mapping problems at a variety of scales. He specializes in interpretation in challenging physical and geologic environments, such as high-relief terrain and areas where the rocks of interest are concealed. USGS areas of focus include the National Cooperative Geologic Mapping and Mineral Resource Programs. He received a PhD in geophysics from the University of Oklahoma in 2009, a MS in geophysics from the University of Texas at El Paso in 2005, and a BS in geological engineering from Michigan Technological University in 2003.
Publications
Drenth, B.J., Grauch, V.J.S., and Rodriguez, B.D., 2013, Geophysical constraints on Rio Grande Rift structure in the central San Luis Basin, Colorado and New Mexico, in Hudson, M.R., and Grauch, V.J.S., eds., New Perspectives on Rio Grande Rift Basins: From Tectonics to Groundwater: Geological Society of America Special Paper 494, p. 75-99, doi:10.1130/2013.2494(04) [Link]
Science and Products
Geophysics of the Midcontinent Rift Region
The Midcontinent Rift system and surrounding Precambrian rocks are known to host highly significant mineral resources. Our project objectives are to increase understanding of this system through the integration of new and legacy geophysical data with geochemical and borehole data, map the lithology and structure of PreCambrian rocks, and develop an integrated 3D geologic model of the region....
A shifting rift—Geophysical insights into the evolution of Rio Grande rift margins and the Embudo transfer zone near Taos, New Mexico
We present a detailed example of how a subbasin develops adjacent to a transfer zone in the Rio Grande rift. The Embudo transfer zone in the Rio Grande rift is considered one of the classic examples and has been used as the inspiration for several theoretical models. Despite this attention, the history of its development into a major rift...
Grauch, V.J.S.; Bauer, Paul W.; Drenth, Benjamin J.; Kelson, Keith I. Geophysical expression of buried range-front embayment structure: Great Sand Dunes National Park, Rio Grande rift, Colorado
Great Sand Dunes National Park and Preserve (GRSA, Colorado) lies along the eastern margin of the San Luis Basin and the tectonically active Sangre de Cristo fault system that are part of the northern Rio Grande rift. GRSA lies within a prominent embayment in the range front where two separate sections of the Sangre de Cristo fault system...
Drenth, Benjamin J.; Grauch, V. J.; Ruleman, Chester A.; Schenk, Judith A Geologic map and cross sections of the Embudo Fault Zone in the Southern Taos Valley, Taos County, New Mexico
The southern Taos Valley encompasses the physiographic and geologic transition zone between the Picuris Mountains and the San Luis Basin of the Rio Grande rift. The Embudo fault zone is the rift transfer structure that has accommodated the kinematic disparities between the San Luis Basin and the Española Basin during Neogene rift extension. The...
Bauer, Paul W.; Kelson, Keith I.; Grauch, V.J.S.; Drenth, Benjamin J.; Johnson, Peggy S.; Aby, Scott B.; Felix, Brigitte Physical properties by geologic unit in the southern San Luis Basin, New Mexico
Physical properties of geologic units are important for geophysical interpretation because they provide the tie between lithology and geophysical fields. For gravity data, the applicable physical property is bulk density, which is the overall mass per unit volume of rocks, sediments, and their pore spaces. Bulk dry density is the mass per unit...
Grauch, V. J.; Drenth, Benjamin J. Principal facts of gravity data in the southern San Luis Basin, northern New Mexico
Gravity data were collected from 2006 through 2015 to assist in mapping subsurface geology in the southern San Luis Basin, northern New Mexico. This data release provides principal facts for 566 new gravity stations that were acquired to fill in gaps in the existing public gravity data coverage.
Drenth, Benjamin J. Geologic cross sections and preliminary geologic map of the Questa Area, Taos County, New Mexico
In 2011, the senior authors were contacted by Ron Gardiner of Questa, and Village of Questa Mayor Esther Garcia, to discuss the existing and future groundwater supply for the Village of Questa. This meeting led to the development of a plan in 2013 to perform an integrated geologic, geophysical, and hydrogeologic investigation of the Questa area by...
Bauer, Paul W.; Grauch, V.J.S.; Johnson, Peggy S.; Thompson, Ren A.; Drenth, Benjamin J.; Kelson, Keith I.
Preliminary geophysical interpretations of regional subsurface geology near the Questa Mine Tailing Facility and Guadalupe Mountain, Taos County, New Mexico
This report presents geophysical interpretations of regional subsurface geology in the vicinity of the Tailing Facility of the Questa Mine near Guadalupe Mountain, Taos County, New Mexico, in cooperation with the New Mexico Environment Department. The interpretations were developed from aeromagnetic data, regional gravity data, data from four...
Grauch, V.J.S.; Drenth, Benjamin J.; Thompson, Ren A.; Bauer, Paul W. What lies beneath: geophysical mapping of a concealed Precambrian intrusive complex along the Iowa–Minnesota border
Large-amplitude gravity and magnetic highs over northeast Iowa are interpreted to reflect a buried intrusive complex composed of mafic–ultramafic rocks, the northeast Iowa intrusive complex (NEIIC), intruding Yavapai province (1.8–1.72 Ga) rocks. The age of the complex is unproven, although it has been considered to be Keweenawan (∼1.1 Ga)....
Drenth, Benjamin J.; Anderson, Raymond R.; Schulz, Klaus J.; Feinberg, Joshua M.; Chandler, Val W.; Cannon, William F. Geophysical expression of a buried niobium and rare earth element deposit: the Elk Creek carbonatite, Nebraska, USA
The lower Paleozoic Elk Creek carbonatite is a 6–8-km-diameter intrusive complex buried under 200 m of sedimentary rocks in southeastern Nebraska. It hosts the largest known niobium deposit in the U.S. and a rare earth element (REE) deposit. The carbonatite is composed of several lithologies, the relations of which are poorly understood. Niobium...
Drenth, Benjamin J.
Porphyry copper assessment of eastern Australia: Chapter L in Global mineral resource assessment
The U.S. Geological Survey (USGS) conducts national and global assessments of resources (mineral, energy, water, and biologic) to provide science in support of decision making. Mineral resource assessments provide syntheses of available information about where mineral deposits are known and suspected to occur in the Earth’s crust and which...
Bookstrom, Arthur A.; Len, Richard A.; Hammarstrom, Jane M.; Robinson, Gilpin R.; Zientek, Michael L.; Drenth, Benjamin J.; Jaireth, Subhash; Cossette, Pamela M.; Wallis, John C. Late Miocene-Pleistocene evolution of a Rio Grande rift subbasin, Sunshine Valley-Costilla Plain, San Luis Basin, New Mexico and Colorado
The Sunshine Valley-Costilla Plain, a structural subbasin of the greater San Luis Basin of the northern Rio Grande rift, is bounded to the north and south by the San Luis Hills and the Red River fault zone, respectively. Surficial mapping, neotectonic investigations, geochronology, and geophysics demonstrate that the structural, volcanic, and...
Ruleman, C.A.; Thompson, R.A.; Shroba, R.R.; Anderson, M.; Drenth, B.J.; Rotzien, J.; Lyon, J. Advancements in understanding the aeromagnetic expressions of basin-margin faults—An example from San Luis Basin, Colorado
Advancements in aeromagnetic acquisition technology over the past few decades have led to greater resolution of shallow geologic sources with low magnetization, such as intrasedimentary faults and paleochannels. Detection and mapping of intrasedimentary faults in particular can be important for understanding the overall structural setting of an...
Grauch, V. J.; Bedrosian, Paul A.; Drenth, Benjamin J.
Less than One Percent of the United States Covered by Aeromagnetic Data that Meet Modern Standards
Less than one percent of the United States is mapped by aeromagnetic data that fully meet modern standards and best practices, according to a recent evaluation by the U.S. Geological Survey. Less than five percent of the country has been mapped with data that can be considered adequate in meeting those same standards
Media Advisory: Low-Level Flights to Begin Assessing Local Mineral Resources this Monday
U.S. Geological Survey scientists will conduct a high-resolution airborne survey to study the rock layers under a region of northeastern Iowa, starting Monday, October 19, and lasting into November.