48282-SE
Karst from Recent to Reservoirs: International Conference on Paleokarst and Multi-Permeability Flow Systems, June 7-10, 2008, Rapid City, SD
This conference was sponsored by the Karst Waters Institute and took place at the Rushmore Plaza Civic Center, Rapid City, South Dakota, USA, June 6 to 11. The technical sessions included two and one-half days of talks and a poster/core session. A full-day field trip led by Art Palmer (State University of New York-Oneonta) examined the present day and paleo- karst of the Black Hills region. Participants had ample opportunity for personal interaction at several receptions, as well as a banquet where Bill Stone (Stone Aerospace) presented the lecture "Autonomous Exploration, Mapping, and Characterization of Channelized Karst Aquifers". Attendance of foreign keynote speakers was supported by an ACS-PRF grant. The meeting concluded with a committee-of-the-whole discussing the outcomes of the event, as well as future directions.
A main goal of the meeting was to promote exchange between researchers working in modern karst systems and those who explore paleokarst reservoirs for petroleum production. This aspiration was amply met with strong participation from both constituencies, and great interest in the varied types of data presented.
Many of the presentations emphasized the common theme of structure-process-time, reminding us that there is great value in understanding these challenging systems using traditional geological concepts. However, this does not (necessarily) mean using low-tech approaches, and there were many presentations using advanced technologies, computed tomography, digital simulations, etc. Conceptual models have been much refined since earlier meetings on this topic. In particular, it is now recognized that hypogenic karst, formed through deep-seated dissolution processes, may be much more widespread than previously considered. This brings in to light some problems with terminology, because the word "karst" as originally defined was based upon near surface geologic processes. In addition, it is quite likely that many reservoirs, which might at first pass be considered "buried karst", might actually never have been subjected to surficial processes. Where would such reservoirs fit in a sequence-stratigraphic framework? This emphasizes the importance of employing modern field studies for the recognition of correct reservoir analogs. Investigations of both active and inactive systems at scales ranging from sub-millimeter (thin sections, SEM) to multi-kilometer (wellfield, cave surveying, geophysics) all provide important insights that will benefit exploration and development. The benefit of using core and imaging logs was recognized, though caution must be exercised because a single well samples only a limited portion of the reservoir. The assembled scientists were reticent to suggest any changes to definitions or classification schemes, but instead emphasized the value of detailed characterization of each field/setting.
Areas that were identified as valuable for future research included:
The role of microorganisms in porosity development
Consequences of global icehouse/greenhouse settings
Consequences of global calcite/aragonite seawater chemistry
"Dekarstification" by sediment infill-mechanical collapse-precipitation
Mechanisms for deep sediment infilling
Synchronous carbonate deposition and karst development
The role of ore-generating MVT processes
Going beyond modern systems by modeling
Applying results of aquifer studies to petroleum reservoirs.
Conference co-chairmen were Chip Feazel (ConocoPhillips, Houston), John Mylroie (Mississippi State University) and Ira D. Sasowsky (University of Akron, Ohio). Cooperating organizations for the meeting were: ConocoPhillips, Chevron, Edwards Aquifer Authority, National Cave and Karst Research Institute (U.S.), National Park Service (U.S.), U.S. Geological Survey, American Association of Petroleum Geologists, and the American Chemical Society Petroleum Research Fund. There were 85 participants representing Australia, Belgium, Canada, China, Czech Republic, France, Hungary, Italy, Mexico, Slovenia, Spain, Ukraine, United Kingdom, and United States.
The proceedings, including extended abstracts and a 34 page full-color field trip guide have been issued as KWI Special Publication 14, and are available for purchase from the Karst Waters Institute website.
