Geoffrey Phelps, MSc
Phelps works in the GMEG Science Center. He received a BA in geology from UC Berkeley and an MSc from the University of London, Birkbeck in geographic information science. He specializes in geologic mapping, gravity and magnetics, and spatial analysis. Presently his research is focused on using data science tools in 2D and 3D geologic mapping, and gravity and magnetic forward and inverse modeling.
Science and Products
Filter Total Items: 29
Preliminary surficial geologic map database of the Amboy 30 x 60 minute quadrangle, California Preliminary surficial geologic map database of the Amboy 30 x 60 minute quadrangle, California
The surficial geologic map database of the Amboy 30x60 minute quadrangle presents characteristics of surficial materials for an area approximately 5,000 km2 in the eastern Mojave Desert of California. This map consists of new surficial mapping conducted between 2000 and 2005, as well as compilations of previous surficial mapping. Surficial geology units are mapped and described based on
Authors
David R. Bedford, David M. Miller, Geoffrey A. Phelps
A Preliminary Investigation of The Structure of Southern Yucca Flat, Massachusetts Mountain, and CP Basin, Nevada Test Site, Nevada, Based on Geophysical Modeling A Preliminary Investigation of The Structure of Southern Yucca Flat, Massachusetts Mountain, and CP Basin, Nevada Test Site, Nevada, Based on Geophysical Modeling
New gravity and magnetic data collected in the vicinity of Massachusetts Mountain and CP basin (Nevada Test Site, NV) provides a more complex view of the structural relationships present in the vicinity of CP basin than previous geologic models, helps define the position and extent of structures in southern Yucca Flat and CP basin, and better constrains the configuration of the basement...
Authors
Geoffrey A. Phelps, Leigh Justet, Barry C. Moring, Carter W. Roberts
Preliminary gravity inversion model of basins east of Yucca Flat, Nevada Test Site, Nevada Preliminary gravity inversion model of basins east of Yucca Flat, Nevada Test Site, Nevada
No abstract available.
Authors
Geoffrey A. Phelps, Carter W. Roberts, Barry C. Moring
Modeling of the Climax Stock and Related Plutons Based on the Inversion of Magnetic Data, Southwest Nevada Modeling of the Climax Stock and Related Plutons Based on the Inversion of Magnetic Data, Southwest Nevada
Two models of the Climax and Gold Meadows stocks were generated using a new method of magnetic inversion modeling based on the pseudogravity anomaly. The first model examined the shape of the two stocks and their connection at depth, concluding that the stocks are connected -4000 m below the ground surface. The second model re-examined the shape and depth of the Climax stock using a two...
Authors
Geoffrey A. Phelps, Robert C. Jachens, Barry C. Moring, Carter W. Roberts
Geologic map of the Hiller Mountain Quadrangle, Clark County, Nevada, and Mohave County, Arizona Geologic map of the Hiller Mountain Quadrangle, Clark County, Nevada, and Mohave County, Arizona
Map Scale: 1:24,000 Map Type: colored geologic map The Hiller Mountains Quadrangle straddles Virgin Canyon in the eastern part of Lake Mead. Proterozoic gneisses and granitoid rocks underlie much of the quadrangle. They are overlain by upper Miocene basin-filling deposits of arkosic conglomerate, basalt, and the overlying Hualapai Limestone. Inception of the Colorado River followed...
Authors
Keith A. Howard, Simon Hook, Geoffrey A. Phelps, Debra L. Block
Preliminary gravity inversion model of Frenchman Flat Basin, Nevada Test Site, Nevada Preliminary gravity inversion model of Frenchman Flat Basin, Nevada Test Site, Nevada
The depth of the basin beneath Frenchman Flat is estimated using a gravity inversion method. Gamma-gamma density logs from two wells in Frenchman Flat constrained the density profiles used to create the gravity inversion model. Three initial models were considered using data from one well, then a final model is proposed based on new information from the second well. The preferred model...
Authors
Geoffrey A. Phelps, Scott E. Graham
Science and Products
Filter Total Items: 29
Preliminary surficial geologic map database of the Amboy 30 x 60 minute quadrangle, California Preliminary surficial geologic map database of the Amboy 30 x 60 minute quadrangle, California
The surficial geologic map database of the Amboy 30x60 minute quadrangle presents characteristics of surficial materials for an area approximately 5,000 km2 in the eastern Mojave Desert of California. This map consists of new surficial mapping conducted between 2000 and 2005, as well as compilations of previous surficial mapping. Surficial geology units are mapped and described based on
Authors
David R. Bedford, David M. Miller, Geoffrey A. Phelps
A Preliminary Investigation of The Structure of Southern Yucca Flat, Massachusetts Mountain, and CP Basin, Nevada Test Site, Nevada, Based on Geophysical Modeling A Preliminary Investigation of The Structure of Southern Yucca Flat, Massachusetts Mountain, and CP Basin, Nevada Test Site, Nevada, Based on Geophysical Modeling
New gravity and magnetic data collected in the vicinity of Massachusetts Mountain and CP basin (Nevada Test Site, NV) provides a more complex view of the structural relationships present in the vicinity of CP basin than previous geologic models, helps define the position and extent of structures in southern Yucca Flat and CP basin, and better constrains the configuration of the basement...
Authors
Geoffrey A. Phelps, Leigh Justet, Barry C. Moring, Carter W. Roberts
Preliminary gravity inversion model of basins east of Yucca Flat, Nevada Test Site, Nevada Preliminary gravity inversion model of basins east of Yucca Flat, Nevada Test Site, Nevada
No abstract available.
Authors
Geoffrey A. Phelps, Carter W. Roberts, Barry C. Moring
Modeling of the Climax Stock and Related Plutons Based on the Inversion of Magnetic Data, Southwest Nevada Modeling of the Climax Stock and Related Plutons Based on the Inversion of Magnetic Data, Southwest Nevada
Two models of the Climax and Gold Meadows stocks were generated using a new method of magnetic inversion modeling based on the pseudogravity anomaly. The first model examined the shape of the two stocks and their connection at depth, concluding that the stocks are connected -4000 m below the ground surface. The second model re-examined the shape and depth of the Climax stock using a two...
Authors
Geoffrey A. Phelps, Robert C. Jachens, Barry C. Moring, Carter W. Roberts
Geologic map of the Hiller Mountain Quadrangle, Clark County, Nevada, and Mohave County, Arizona Geologic map of the Hiller Mountain Quadrangle, Clark County, Nevada, and Mohave County, Arizona
Map Scale: 1:24,000 Map Type: colored geologic map The Hiller Mountains Quadrangle straddles Virgin Canyon in the eastern part of Lake Mead. Proterozoic gneisses and granitoid rocks underlie much of the quadrangle. They are overlain by upper Miocene basin-filling deposits of arkosic conglomerate, basalt, and the overlying Hualapai Limestone. Inception of the Colorado River followed...
Authors
Keith A. Howard, Simon Hook, Geoffrey A. Phelps, Debra L. Block
Preliminary gravity inversion model of Frenchman Flat Basin, Nevada Test Site, Nevada Preliminary gravity inversion model of Frenchman Flat Basin, Nevada Test Site, Nevada
The depth of the basin beneath Frenchman Flat is estimated using a gravity inversion method. Gamma-gamma density logs from two wells in Frenchman Flat constrained the density profiles used to create the gravity inversion model. Three initial models were considered using data from one well, then a final model is proposed based on new information from the second well. The preferred model...
Authors
Geoffrey A. Phelps, Scott E. Graham