LGS Administrative Staff


Chacko J. John, PhD
Email: cjohn@lsu.edu
Telephone: 225-578-8681

Chacko J. John is Director, State Geologist and Professor-Research at the Louisiana Geological Survey (LGS), Louisiana State University (LSU). He holds M.S. and Ph.D degrees in Geology from the University of Delaware, and B.Sc. and M.Sc. Degrees in Geology from the University of Nagpur (India). Prior to his present position he served as Director of the Basin Research Institute of Louisiana State University, which is now the Basin Research Energy Section of the LGS.

John joined the LGS in 1987 and subsequently held the positions of Assistant Professor-Research, Associate Professor-Research, Chief, Energy and Mineral Resources Section, and Director of Research before being appointed to his current position in 1997. He has previously served as an advanced geologist with Marathon Oil Company, as a senior exploration geologist with Geo Consultants International, and as geologist-in-charge of the Akula Clay mine with English India Clays Ltd.

John is a member of many professional associations and has served as president of the Louisiana Section of the American Institute of Professional Geologists (AIPG), the Energy Minerals Division of the American Association of Petroleum Geologists (AAPG), the Gulf Coast Association of Geological Societies (GCAGS), and the Baton Rouge Geological Society. He was elected as a Fellow of the Geological Society of America in 2004, has been a recipient of professional society awards, and is the author and/or co-author of numerous technical reports, book chapters, professional presentations and journal publications.

His fields of research specialization are petroleum geology, sedimentology, reservoir characterization, depositional environments and models of clastic sandstone reservoirs, geopressured-geothermal energy resources, coastal geomorphology and environmental geology.

Chacko J. John, PhD projects


Marty Horn, PhD
Acting Assistant Director
Email: mhorn@lsu.edu
Telephone: 225-578-2681
Marty Horn joined the Louisiana Geological Survey as an assistant professor of research in January 2007. He had previously been employed at LSU since 2002 as an instructor in the LSU Department of Geology and Geophysics, where he also served as the field camp director.Horn earned a B.S. in Geophysics at the University of Oklahoma in 1982, an M.S. in Geology at the Arizona State University in 1986, and a Ph.D. in Mathematical Sciences & Geology at the University of Texas at Arlington in 1996. After graduation he taught courses in Mineralogy, Petrology, Volcanology, and Field Geology at UTA as an adjunct professor.While at UTA Horn also worked as a geologist for Snyder Oil Company, where he primarily focused on the Hosston and Cotton Valley trends of north Louisiana. At the LGS he has returned to full-time research on north Louisiana oil and gas reserves.

Marty Horn projects


John E. Johnston III, PG, CPG

Retired Assistant Director
Email: hammer@lsu.edu
Telephone: 225-578-5320

John is the Assistant Director emeritus of the Louisiana Geological Survey He holds undergraduate and graduate degrees in geological sciences from the University of Southern California and the University of Texas and served as a geologist for Shell Oil Company, Exxon Company, USA, and the Texas Bureau of Economic Geology. He has variously served as part-time faculty and taught petroleum engineering, English, geography, and geology at Louisiana State University (LSU) and taught geology at the University of Louisiana at Lafayette (ULL), where he was an adjunct full professor. John currently serves as chairman of the Louisiana Stratigraphic Commission and is a past president and past director of the Baton Rouge Geological Society. Johnston joined the LGS - when it was still part of the Louisiana Department of Natural Resources (DNR) - from Exxon as a Senior Research Geologist, was later named Chief Economic Geologist and then Deputy Director, and also served for several years as the acting head of the LGS. His title changed to Assistant Director when the Louisiana Legislature transferred the LGS from DNR to LSU in 1997. Johnston is the author and/or co-author of a number of publications, including the Official Stratigraphic Charts of Louisiana. His areas of particular expertise are environmental geology, petroleum geology, coal geology, and subsurface geology. LGS emergency support teams under John's leadership, detached from the LGS during critical emergencies, have been repeatedly commended for their emergency, scientific support, mapping, and search and rescue efforts during and after hurricanes - including Andrew, Katrina, Rita, Gustav, and Ike - and have been credited with saving lives. John is a Certified Professional Geologist and a Licensed Professional Geoscientist and is the recipient of a Louisiana Governor's Award for outstanding public service. He was appointed by the governor to the Louisiana Board of Professional Geoscientists in 2012 and is the board's chairman emeritus and vice-chairman. John is also a published fiction and non-fiction author and a member of the Science Fiction and Fantasy Writers of America (SFWA) as well as a recipient of a Nebula Award, SFWA's highest honor.


Melissa Esnault
Office Coordinator
Email: mesnau1@lsu.edu
Telephone: 225-578-5320
Melissa Esnault is the Office Coordinator of the LGS. She graduated from Louisiana Tech University in Ruston, Louisiana, in 2000 with a B.S. degree in Family Studies with a concentration in Early Childhood Development. Melissa joined LSU in 2007 as a Coordinator in LSU’s Office of Human Resources, where she was the assistant to the associate vice chancellor of Human Resource Management. She was previously employed as an inside sales representative by the Tembec Paper Corporation in St. Francisville, Louisiana and as an executive administrative assistant by the eFederal Credit Union in Baton Rouge. Melissa joined the LGS in 2010. 


Jeanne Johnson
Accounting Technician
Email: jeannej@lsu.edu
Telephone: 225-578-8407
Jeanne Johnson is the Accounting Technician for the Louisiana Geological Survey and handles all LGS grants, contracts and budgets. Johnson came to work at LSU in 1991 and has worked for the Department of Oceanography and Coastal Sciences, the Coastal Studies Institute and the School of Veterinary Medicine. Jeanne assists LGS researchers in the preparation of their proposal budgets and provides the staff with their respective monthly budget summaries.


Patrick O’Neill
Research Associate 3
Email: poneil2@lsu.edu
Telephone: 225-578-8590

Patrick O’Neill received a B.S. degree from the LSU School of Forestry in 1985 and worked in photogrammetry before joining the LGS. Pat is in charge of LGS Publications Office as well as the LGS core and well log libraries and facilities. He has experience with GPS data collection and related field work techiques.