Michael J Stephens
Michael J. Stephens is a Research Hydrologist with the USGS California Water Science Center, working in the Groundwater program area.
Michael's research focuses on water resources, particularly groundwater in sedimentary basins. He develops subsurface models of hydrogeologic systems including groundwater salinity, stratigraphy, porosity, temperature, and fault zones which help identify water resources.
Professional Experience
Research Hydrologist, USGS, 2022-present
Hydrologist, USGS, 2017-2022
Education and Certifications
MS, Geology, California State University, Sacramento, 2017
BS, Geology, University of Southern Indiana, 2015
Science and Products
Filter Total Items: 15
Groundwater salinity and the effects of produced water disposal in the Lost Hills-Belridge oilfields, Kern County, California Groundwater salinity and the effects of produced water disposal in the Lost Hills-Belridge oilfields, Kern County, California
Increased oil and gas production in many areas has led to concerns over the effects these activities may be having on nearby groundwater quality. In this study we determine the lateral and vertical extent of groundwater with less than 10,000 milligrams per liter (mg/l) total dissolved solids (TDS) near the Lost Hills-Belridge oilfields in northwestern Kern County, California and document...
Authors
Janice M. Gillespie, Tracy Davis, Michael J. Stephens, Lyndsay B. Ball, Matthew K. Landon
Groundwater salinity mapping using geophysical log analysis within the Fruitvale and Rosedale Ranch oil fields, Kern County, California, USA Groundwater salinity mapping using geophysical log analysis within the Fruitvale and Rosedale Ranch oil fields, Kern County, California, USA
A method is presented for deriving a volume model of groundwater total dissolved solids (TDS) from borehole geophysical and aqueous geochemical measurements. While previous TDS mapping techniques have proved useful in the hydrogeologic setting in which they were developed, they may yield poor results in settings with lithological heterogeneity, complex water chemistry, or limited data...
Authors
Michael J. Stephens, David H. Shimabukuro, Janice M. Gillespie, Will Chang
Tracing enhanced oil recovery signatures in casing gases from the Lost Hills oil field using noble gases Tracing enhanced oil recovery signatures in casing gases from the Lost Hills oil field using noble gases
Enhanced oil recovery (EOR) and hydraulic fracturing practices are commonly used methods to improve hydrocarbon extraction efficiency; however the environmental impacts of such practices remain poorly understood. EOR is particularly prevalent in oil fields throughout California where water resources are in high demand and disposal of high volumes of produced water may affect groundwater...
Authors
Peter H. Barry, Justin T. Kulongoski, Matthew K. Landon, R. L. Tyne, Janice M. Gillespie, Michael J. Stephens, D.J. Hillegonds, D.J. Byrne, C.J. Ballentine
Science and Products
Filter Total Items: 15
Groundwater salinity and the effects of produced water disposal in the Lost Hills-Belridge oilfields, Kern County, California Groundwater salinity and the effects of produced water disposal in the Lost Hills-Belridge oilfields, Kern County, California
Increased oil and gas production in many areas has led to concerns over the effects these activities may be having on nearby groundwater quality. In this study we determine the lateral and vertical extent of groundwater with less than 10,000 milligrams per liter (mg/l) total dissolved solids (TDS) near the Lost Hills-Belridge oilfields in northwestern Kern County, California and document...
Authors
Janice M. Gillespie, Tracy Davis, Michael J. Stephens, Lyndsay B. Ball, Matthew K. Landon
Groundwater salinity mapping using geophysical log analysis within the Fruitvale and Rosedale Ranch oil fields, Kern County, California, USA Groundwater salinity mapping using geophysical log analysis within the Fruitvale and Rosedale Ranch oil fields, Kern County, California, USA
A method is presented for deriving a volume model of groundwater total dissolved solids (TDS) from borehole geophysical and aqueous geochemical measurements. While previous TDS mapping techniques have proved useful in the hydrogeologic setting in which they were developed, they may yield poor results in settings with lithological heterogeneity, complex water chemistry, or limited data...
Authors
Michael J. Stephens, David H. Shimabukuro, Janice M. Gillespie, Will Chang
Tracing enhanced oil recovery signatures in casing gases from the Lost Hills oil field using noble gases Tracing enhanced oil recovery signatures in casing gases from the Lost Hills oil field using noble gases
Enhanced oil recovery (EOR) and hydraulic fracturing practices are commonly used methods to improve hydrocarbon extraction efficiency; however the environmental impacts of such practices remain poorly understood. EOR is particularly prevalent in oil fields throughout California where water resources are in high demand and disposal of high volumes of produced water may affect groundwater...
Authors
Peter H. Barry, Justin T. Kulongoski, Matthew K. Landon, R. L. Tyne, Janice M. Gillespie, Michael J. Stephens, D.J. Hillegonds, D.J. Byrne, C.J. Ballentine