Sixty percent of the world's oil reserves are located in carbonate reservoirs. Carbonates have been a challenge to interpret, drill and produce the resource for industrial feedstock needed for providing finished products in the fuel, plastic, industrial chemical, and pharmaceutical industries. Let us spend some time getting to know a carbonate geologist, Larry Baria, with 48 years of experience and his search for reserves in subsurface carbonates as we get down to Earth.
Rene: How did you get interested in Geology?
Larry: As a child I loved collecting rocks, minerals, and fossils. I was encouraged by my civil engineer father who would bring home shiny chunks of granite rip-rap from Lake Lanier Dam in Georgia, Fort Union calcite from the Garrison Dam in North Dakota, or quartz crystals from the Blakey Mountain Dam in Arkansas.
My dad’s two brothers, Pete and Joe Baria, were geologists who shared their old college geology texts with me which also provided a lot of encouragement to a nerdy six year old kid. I was washing dirt samples looking for forams with my “toy” microscope by the time I was seven. I just never lost that awe and wonder about fossils and minerals.
Rene: I understand you are mineral collector with 1000's of specimens. What is your most exotic or favorite mineral?
Larry: Wow, that’s a tough question! Maybe a small fist-sized gold in quartz nugget from Australia (Figure 1)
or a large emerald green tourmaline from the Pederneira Mines in Brazil (Figure 2).
I also love the reds, oranges, and yellows of Arizona wulfenites. There are so many facets to a mineral from structure, color, composition, and location. Each mineral is so different. Even the same mineral from different locations can be unique and this awe and wonder drives my desire to collect the next specimen.
Rene: What attracted you to carbonate reservoirs?
Larry: While in college, two wonderful professors, Dr. Leonard Young and Dr. Clyde Moore, introduced me to carbonates. Carbonate geology was exciting in that one could see how lithologic facies could be associated with and identified by different marine animals, controlled by depositional environments and flow regimes.
After college, I went to work with Getty Oil Co.’s Research and Development Rock Studies Program led by Dr. Susan Longacre and they sent me to Ginsburg’s two-week field trip in the Florida Keys and Bahamas; I was hooked! By the way, the assistants on that trip, who were graduate and post-doc students at the time, were Wolfgang Slagger, Mitch Harris, and Paul Crevello. How could I not now love carbonates! Not to mention the turquoise water, white sand beaches, and Bahamian rum.
Rene: As a core interpreter, what challenges have you encountered with well logs calibrated to core?
Larry: I do love core description and have probably logged at least 10,000 feet or so mainly from the Permian Basin, on-shore Jurassic-Cretaceous Gulf Coast, eastern Saudi, some Paleozoics from the Mid-continent, and the northern Rockies.
Regarding logs calibrated to core; one really needs a formation imaging log to even come close to understanding the detail between core and log.
Rene: While geologists use well logs every day, the theory behind the logging tool is very much a geophysical method. Would you agree?
Larry: Yes. Logs are a remotely-derived, electrical, acoustic, and radioactive approximations of the rock and its fluid content. I’m not a log analysist by any means, however, I fortunately know a few good petrophysicists I can rely on in my professional network.
Rene: Are there any interesting field stories from Getty Oil days or from leading carbonate field trips?
Larry: I have loved all the field work I’ve ever done: Miocene fluvio-deltaic rocks of central Louisiana, Mississippi, and Alabama, the southwest desert, Ouachita and Ozark mountains, the Brooks Range, Central Italy, Bahamas, Wyoming and Montana... I love it all!
The most challenging and memorable field adventure was hiking the Muskeg in the Northern Brooks Range in Alaska with a 60 pound pack for a couple of weeks. I’m glad I had two good friends, Robert Handford and Bob LoPiccolo, along to share the misery and adventure. It was nice mapping the Lisburne Group's oil-saturated vuggy limestones and the nodular barites of the Siksikpuk Formation.
Rene: What is the most challenging downhole problem and solution you encountered?
Larry: For me, the most challenging [problem] has been the low resistivity pays found in the Frisco City Sand of Jurassic age in southern Alabama. There you have chlorite rims on most of the sand grains, plus pebbles and cobbles of chloritic schist and gneiss in an alluvial fan to wadi setting, all interbedded with well sorted inter-mountain dune sands. The porosity varies wildly and permeabilities range from 0.05 millidarcies to 5 darcies. Had we not taken conventional cores on almost every well and followed up with thin section petrography and x-ray diffraction (XRD), we would have floundered around and drilled a lot of dry holes based solely on seismic and logs. The high irreducible waters of the chlorite rims and the matrix clays of the gravelly alluvial fan facies would have disguised a lot of oil productive zones; that was a nice challenge to have.
Rene: How would you compare working for a major company like Getty Oil and working as an independent?
Larry: Getty EPR was a FANTASTIC experience: great people to work with, frequent field trips, continuing education experiences, cores coming in from all over the world, wonderful library access. And did I mention the great people I had a chance to work with? As an independent you don’t have those opportunities. Sure, you have more freedom of hours and direction of what to work on… but there is a constant need to bounce ideas off of a colleague who may or may not always be around. You have to worry about lining up the next job, bookkeeping, taxes, legalities, and often not enough time to do the thing one loves: Geology.
Rene: I understand that you invest your time and money in mentoring the next generation of geologists. What advice would you offer a young professional?
Larry: Having supported many graduate research projects, served on theses and dissertation committees, and been an adjunct at Ole Miss and Alabama, it’s been a wonderful way to stay updated with new geologic ideas and trends. I’d advise any young geoscientist to stay with a major or large independent for the first ten years or so. To a student I would say “take EVERY single geology course you can: mineralogy, paleontology, geomorphology, geochemistry, carbonate petrology, sandstone petrology, stratigraphy, structure, geophysics, clay mineralogy, micro-paleontology, igneous petrology, metamorphic petrology, whatever. You will use it all!" If you can’t bear the credit hour load, then at least audit it or sit in on the class.
Rene: It has been a pleasure to converse with you Larry about your love of the geological sciences. Your enthusiasm is felt in all aspects of your work with core, thin section, logs, minerals collecting, and mentoring up and coming young geologists. Working with carbonates, while challenging with regards to exploration, production, and drilling, is rewarded with a product that fuels the industrial , private , and medical sectors; shipping; and so much more.