Jim is a Supervisory Geologist and USGS-NASA Planetary Geologic Mapping (PGM) Program Coordinator. He specializes in the characterization of planetary landscapes using geologic mapping and comparative terrestrial analogs, with focus on planetary basins, stratigraphic architectures, traverse planning, mapping strategies, and cartographic representation of geologic environments.
Since becoming a USGS geologist in 2000, I have been active in the planetary geologic mapping community and involved in geologic mapping-based training for NASA engineers, managers, astronauts, mission teams, and students. Prior to USGS, I worked in the private sector as a field geologist for both hydrocarbon and environmental industries.
Professional Experience
8/2022 – present : Supervisory Geologist, U.S. Geological Survey, Flagstaff, AZ; Planetary geologic mapping, process strategies, program coordination, project development and management, and personnel supervision.
1/2011 – 8/2022 : Research Geologist, U.S. Geological Survey, Flagstaff, AZ; Planetary geologic mapping, process strategies, and program coordination.
4/2004 – 1/2011 : Geologist, U.S. Geological Survey, Flagstaff, AZ; Planetary geologic mapping and related topical studies.
6/2003 – 4/2004 : Project Geologist, MACTEC, Inc., Raleigh, NC; Geologic mapping and environmental assessments
10/1999 – 6/2003 : Geologic Science Technician, U.S. Geological Survey, Flagstaff, AZ; GIS-based Mars geologic and morphologic mapping.
6/1997 – 8/1999 : Project Geologist, Municipal Engineering Services, Garner, NC; Geologic mapping and design of groundwater monitoring systems
6/1996 – 6/1997 : Onboard Geophysicist (R/V Western Hercules), Houston, TX; Geophysical and navigational support for deep marine seismic surveys
Education and Certifications
Northern Arizona University, M.S. Geology, 2002 (Thesis: Re-characterization of the materials of Utopia Planitia)
Licensed Geologist, State of North Carolina (#2051)
North Carolina State University, B.S. Geology, 1996 (marine science concentration)
Affiliations and Memberships*
NASA Engineer and Manager Geology Field Instructor (2018 – present)
IAU Planetary Nomenclature, Mars Task Group member (2014 – present)
Astronaut Candidate (ASCAN) Geology Field Instructor (2019)
NASA Advisory Council’s Planetary Science Subcommittee member (2016-17)
Mapping and Planetary Spatial Infrastructure Team (MAPSIT) (2015-19)
NASA Space Grant Program mentor (2009, 2016, 2018)
Geologic Mapping Subcommittee member (2009-17), Chair (2011-14)
Honors and Awards
NASA Johnson Space Center Certificate of Appreciation – ASCAN Training (2017)
NASA Group Achievement Award (Desert-RATS Science Team), 2010
USGS Western Region Communicator of the Year, 2009
Science and Products
Planetary geologic mapping protocol—2022
Planetary geologic mapping protocol—2022
Workshop on terrestrial analogs for planetary exploration
A geologic field guide to S P Mountain and its lava flow, San Francisco Volcanic Field, Arizona
Exposure of an early to middle Noachian valley network in three dimensions on Mars
Planetary geologic mapping—Program status and future needs
Towards a planetary spatial data infrastructure
Large crater clustering tool
Widespread loess-like deposit in the Martian northern lowlands identifies Middle Amazonian climate change
Crater-based dating of geological units on Mars: methods and application for the new global geological map
The role of photogeologic mapping in traverse planning: Lessons from DRATS 2010 activities
History of plains resurfacing in the Scandia region of Mars
Emplacement of the youngest flood lava on Mars: A short, turbulent story
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Planetary Geologic Mapping Program
Terrestrial Analogs for Research and Geologic Exploration Training (TARGET)
Terrestrial Analogs for Research and Geologic Exploration Training (TARGET)
Geographic Boundaries Of Planetary Geologic Maps
Appendices for Planetary Geologic Mapping: Program Status and Future Needs
Geologic map of the Nepenthes Planum Region, Mars
Geologic map of Mars
Geologic map of the MTM 85200 quadrangle, Olympia Rupes region of Mars
Geologic map of the Metis Mons quadrangle (V–6), Venus
Geologic map of the northern plains of Mars
Science and Products
- Publications
Planetary geologic mapping protocol—2022
The Planetary Geologic Mapping Protocol covers the idealized process of compiling a NASA-funded map product of a non-terrestrial solid surface planetary body for U.S. Geological Survey (USGS) publication and summarizes technical specifications of the Mapping Process for authors and reviewers. Directed by community and programmatic recommendations, the USGS Planetary Geologic Map Coordination GroupAuthorsJames A. Skinner, Alexandra E. Huff, Sarah R. Black, Holly C. Buban, Corey M. Fortezzo, Tenielle A. Gaither, Trent M. Hare, Marc A. HunterFilter Total Items: 19Planetary geologic mapping protocol—2022
The Planetary Geologic Mapping Protocol covers the idealized process of compiling a NASA-funded map product of a non-terrestrial solid surface planetary body for U.S. Geological Survey (USGS) publication and summarizes technical specifications of the Mapping Process for authors and reviewers. Directed by community and programmatic recommendations, the USGS Planetary Geologic Map Coordination GroupAuthorsJames A. Skinner, Alexandra E. Huff, Sarah R. Black, Holly C. Buban, Corey M. Fortezzo, Tenielle A. Gaither, Trent M. Hare, Marc A. HunterWorkshop on terrestrial analogs for planetary exploration
Terrestrial analogs are an important part of the robotic and human exploration of the solar system. One of the main recommendations from a community survey conducted in 2019 was to hold a workshop to increase communication and share resources among scientists, engineers, data managers, educators, and students who are involved, or hope to be involved, in terrestrial analog studies.AuthorsLauren A. Edgar, Amber Gullikson, M. Elise Rumpf, James SkinnerA geologic field guide to S P Mountain and its lava flow, San Francisco Volcanic Field, Arizona
IntroductionWe created this guide to introduce the user to the San Francisco Volcanic Field as a terrestrial analog site for planetary volcanic processes. For decades, the San Francisco Volcanic Field has been used to teach scientists to recognize the products of common types of volcanic eruptions and associated volcanic features. The volcanic processes and products observed in this volcanic fieldAuthorsAmber L. Gullikson, M. Elise Rumpf, Lauren A. Edgar, Laszlo P. Keszthelyi, James A. Skinner, Lisa ThompsonExposure of an early to middle Noachian valley network in three dimensions on Mars
We document a set of channels in a section of the Martian cratered highlands located between crustal massifs northeast of Hellas Planitia that are visible in cross section and planview >200 m below the surface. The morphometry and spatial distribution of the outcrops provide concrete geological evidence of a dynamic aqueous system in a structural sub-basin during the Early to Middle Noachian, bolsAuthorsJames A. Skinner, Corey M. Fortezzo, Peter J. Mouginis-MarkPlanetary geologic mapping—Program status and future needs
The United States Geological Survey’s (USGS) Planetary Geologic Map Coordination Group (Flagstaff, Ariz.) surveyed planetary geoscience map makers and users to determine the importance, relevance, and usability of such products to their planetary science research and to current and future needs of the planetary science community. This survey was prepared because the planetary science community lacAuthorsJames A. Skinner, Alexandra E. Huff, Corey M. Fortezzo, Tenielle Gaither, Trent M. Hare, Marc A. Hunter, Holly BubanTowards a planetary spatial data infrastructure
Planetary science is the study of planets, moons, irregular bodies such as asteroids and the processes that create and modify them. Like terrestrial sciences, planetary science research is heavily dependent on collecting, processing and archiving large quantities of spatial data to support a range of activities. To address the complexity of storing, discovering, accessing, and utilizing spatial daAuthorsJason Laura, Trent M. Hare, Lisa R. Gaddis, Robin L. Fergason, James Skinner, Justin Hagerty, Brent ArchinalLarge crater clustering tool
In this paper we present the Large Crater Clustering (LCC) tool set, an ArcGIS plugin that supports the quantitative approximation of a primary impact location from user-identified locations of possible secondary impact craters or the long-axes of clustered secondary craters. The identification of primary impact craters directly supports planetary geologic mapping and topical science studies whereAuthorsJason Laura, James A. Skinner, Marc A. HunterWidespread loess-like deposit in the Martian northern lowlands identifies Middle Amazonian climate change
Consistently mappable units critical to distinguishing the style and interplay of geologic processes through time are sparse in the Martian lowlands. This study identifies a previously unmapped Middle Amazonian (ca. 1 Ga) unit (Middle Amazonian lowland unit, mAl) that postdates the Late Hesperian and Early Amazonian lowland plains by >2 b.y. The unit is regionally defined by subtle marginal scarpsAuthorsJames A. Skinner, Kenneth L. Tanaka, Thomas PlatzCrater-based dating of geological units on Mars: methods and application for the new global geological map
The new, post-Viking generation of Mars orbital imaging and topographical data provide significant higher-resolution details of surface morphologies, which induced a new effort to photo-geologically map the surface of Mars at 1:20,000,000 scale. Although from unit superposition relations a relative stratigraphical framework can be compiled, it was the ambition of this mapping project to provide abAuthorsThomas Platz, Gregory Michael, Kenneth L. Tanaka, James A. Skinner, Corey M. FortezzoThe role of photogeologic mapping in traverse planning: Lessons from DRATS 2010 activities
We produced a 1:24,000 scale photogeologic map of the Desert Research and Technology Studies (DRATS) 2010 simulated lunar mission traverse area and surrounding environments located within the northeastern part of the San Francisco Volcanic Field (SFVF), north-central Arizona. To mimic an exploratory mission, we approached the region “blindly” by rejecting prior knowledge or preconceived notions ofAuthorsJames A. Skinner, Corey M. FortezzoHistory of plains resurfacing in the Scandia region of Mars
We present a preliminary photogeologic map of the Scandia region of Mars with the objective of reconstructing its resurfacing history. The Scandia region includes the lower section of the regional lowland slope of Vastitas Borealis extending about 500–1800 km away from Alba Mons into the Scandia sub-basin below −4800 m elevation. Twenty mapped geologic units express the diverse stratigraphy of theAuthorsKenneth L. Tanaka, Corey M. Fortezzo, Rosalyn K. Hayward, J. Alexis P. Rodriguez, James A. SkinnerEmplacement of the youngest flood lava on Mars: A short, turbulent story
Recently acquired data from the High Resolution Imaging Science Experiment (HiRISE), Context (CTX) imager, and Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) onboard the Mars Reconnaissance Orbiter (MRO) spacecraft were used to investigate the emplacement of the youngest flood-lava flow on Mars. Careful mapping finds that the Athabasca Valles flood lava is the product of a single eruAuthorsWindy L. Jaeger, Laszlo P. Keszthelyi, James A. Skinner, Moses P. Milazzo, Alfred S. McEwen, Timothy N. Titus, Mark R. Rosiek, Donna M. Galuszka, Elpitha Howington-Kraus, Randolph L. KirkNon-USGS Publications**
Skinner, J.A., Jr., Fortezzo, C.M., and Mouginis-Mark, P.J., 2021, Exposure of an Early to Middle Noachian valley network in three dimensions on Mars, Icarus, 354 (doi:10.1016/j.icarus.2020.114071).Laura, J., Skinner, J.A., Jr., and Hunter, M.A., 2017, Large Crater Clustering Tool, Computers and Geosciences, 105 (doi:10.1016/j.cageo.2017.04.011).Skinner, J.A., Jr., and Fortezzo, C.M., 2013, The role of photogeologic mapping in traverse planning: Lessons from DRATS 2010 activities, Acta Astronautica (doi:10.1016/j.actaastro.2011.11.011).Skinner, J.A., Jr., Tanaka, K.L., and Platz, T., 2012, Widespread loess-like deposit in the Martian northern lowlands identified Middle Amazonian climate change, Geology (doi:10.1130/G33513).Jaeger, W.L., Keszthelyi, L.P., Skinner, J.A., Jr., Milazzo, M.P., McEwen, A.S., Titus, T.N., Rosiek, M.R., Galuszka, D.M., Howington-Kraus, E., Kirk, R.L., and the HiRISE Team, 2010, Emplacement of the youngest flood lavas on Mars: A short, turbulent story, Icarus, v. 205, no. 1. (doi:10.1016/j.icarus.2009.09.011).Skinner, J.A., Jr. and Mazzini, A., 2009, Martian mud volcanism: Terrestrial analogs and implications for formational scenarios, Journal of Marine and Petroleum Geology, 26, 1866-1878 (doi:10.1026/jmarpetgeo.2009.02.006).Tanaka, K. L., Skinner, J.A., Jr., Crumpler, L., and Dohm, J.M., 2009, Assessment of planetary geologic mapping techniques for Mars using terrestrial analogues: The SP Mountain area of the San Francisco Volcanic Field, Arizona, Planetary and Space Science, 57, 510-532 (doi:10.1026/j.pss.2008.06.012).Tanaka, K.L., Fortezzo, C.M., Hayward, R.K., Rodriguez, J.A.P., and Skinner, J.A., Jr., 2009, History of plains resurfacing in the Scandia region of Mars, Planetary and Space Science, (doi:10.1016/j.pss.2010.11.004).Hare, T.M., Kirk, R.L., Skinner, J.A., Jr., and Tanaka, K.L., 2009, Extraterrestrial GIS, in Manual of Geographic Information Systems, M. Madden (ed.), pp. 1199-1219.Tanaka, K.L., Rodriguez, J.A.P., Skinner, J.A., Jr., Bourke, M.C., Fortezzo, C.M., Herkenhoff, K.E., Kolb, E.J., and Okubo, C.H., 2008. North polar region of Mars: Advances in stratigraphy, structure, and erosional modification, Icarus (doi:10.1016/j.icarus.2008.01.021).Skinner, J.A., Jr. and Tanaka, K.L., 2007. Evidence and implications of sedimentary diapirism in the southern Utopia highland-lowland boundary plain, Mars, Icarus 186. 41-59 (doi:10.1016/j.icarus.2006.08.013).Tanaka, K.L., Carr, M.H., Skinner, J.A., Jr., Gilmore, M.S., and Hare, T.M., 2003, Geology of the MER 2003 “Elysium” candidate landing site in southeastern Utopia Planitia, Mars, J. Geophys. Res. 108 (doi:10.1029/2003JE002054).Tanaka, K.L., Skinner, J.A., Jr., Hare, T.M., Joyal, T., and Wenker, A., 2003, Resurfacing history of the northern plains of Mars based on geologic mapping of Mars Global Surveyor data, J. Geophys. Res., 108 (doi:10.1029/2002JE001908).**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
- Science
Planetary Geologic Mapping ProgramPlanetary Geologic Mapping ProgramTerrestrial Analogs for Research and Geologic Exploration Training (TARGET)Terrestrial Analogs for Research and Geologic Exploration Training (TARGET)
Terrestrial Analogs for Research and Geologic Exploration Training (TARGET)
The U. S. Geological Survey (USGS) Astrogeology Science Center (ASC) recently established the Terrestrial Analogs for Research and Geologic Exploration Training (TARGET) program. This service-oriented program is built around the recognition that the Earth is a fundamental training ground for human and robotic planetary exploration, and that ASC is in a unique position in northern Arizona with... - Data
Geographic Boundaries Of Planetary Geologic Maps
A polygon layer of regions of multiple planetary bodies beyond Earth that are covered by proposed or published planetary geologic maps published by the USGS.Appendices for Planetary Geologic Mapping: Program Status and Future Needs
Appendices include the original survey, response data, and collated results related to the Open File Report. Geoscience maps, regardless of target body, are spatial and temporal representations of materials and processes recorded on planetary surfaces (Varnes, 1973; Spencer, 2000). The information and context provided by these maps promote basic and applied research within and across various geosc - Maps
Geologic map of the Nepenthes Planum Region, Mars
This map product contains a map sheet at 1:1,506,000 scale that shows the geology of the Nepenthes Planum region of Mars, which is located between the cratered highlands that dominate the southern hemisphere and the less-cratered sedimentary plains that dominate the northern hemisphere. The map region contains cone- and mound-shaped landforms as well as lobate materials that are morphologically sGeologic map of Mars
This global geologic map of Mars, which records the distribution of geologic units and landforms on the planet's surface through time, is based on unprecedented variety, quality, and quantity of remotely sensed data acquired since the Viking Orbiters. These data have provided morphologic, topographic, spectral, thermophysical, radar sounding, and other observations for integration, analysis, and iGeologic map of the MTM 85200 quadrangle, Olympia Rupes region of Mars
The north polar region of Mars is dominated by Planum Boreum, a roughly circular, domical plateau that rises >2,500 m above the surrounding lowland. Planum Boreum is >1,500 km in diameter, contains deep, curvilinear troughs and chasmata, isolated cavi, and marginal scarps and slopes. The north polar plateau is surrounded by low-lying and nearly horizontal plains of various surface texture, geologiGeologic map of the Metis Mons quadrangle (V–6), Venus
The Metis Mons quadrangle (V–6) in the northern hemisphere of Venus (lat 50° to 75° N., long 240° to 300° E.) includes a variety of coronae, large volcanoes, ridge and fracture (structure) belts, tesserae, impact craters, and other volcanic and structural features distributed within a plains setting, affording study of their detailed age relations and evolutionary development. Coronae in particulaGeologic map of the northern plains of Mars
The northern plains of Mars cover nearly a third of the planet and constitute the planet's broadest region of lowlands. Apparently formed early in Mars' history, the northern lowlands served as a repository both for sediments shed from the adjacent ancient highlands and for volcanic flows and deposits from sources within and near the lowlands. Geomorphic evidence for extensive tectonic deformatio
*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