New Wave Carbonate Research: What Paleontologists Can Learn from It: A Status Report from Cancun, Mexico

Abstract

Carbonate research in recent years has moved a long way from the emphasis on facies and paleoecology that dominated work in the '60s and early '70sso far, indeed, that traditional paleontologists may view it as an unrelated discipline. Yet much that has been happening of late in carbonate circles has significant application to problems in the mainstream of paleontologic thought, including determination of paleosalinities, paleotemperatures, and the calibration of secular changes through Phanerozoic time. The benefits of interaction between carbonate researchers in industry and academia were crystallized at Cancun last August, as 65 geologists gathered to parade, review, and joust over current research in an SEPM Research Symposium convened by Paul Harris (Chevron Research), Lynton Land (University of Texas), and Peter Scholle (Chevron Research). The symposium title 'Spar Cements and Secondary Porosity in Carbonate Rocks' ensured strong financial support from oil companies and drew almost equal participation from geologists in industry and academia. Participants came from many countries on both sides of the Atlantic, including U.S.A., Canada, Venezuela, Belize, Great Britain, West Germany, and Poland. Four consecutive days of focussed discussion challenged brains as well as derrieres, for sessions began promptly at 8:00 a.m. each morning and continued well past 10:00 p.m. in the evenings, and opportunities were provided for informal discussion still later (should the mind, body, and soul prove capable!). Presentations were organized in four sequential sessions: (1)Surficial Processes, (2) Burial Processes, (3) Analytical Methods, and (4) Review: Comparison of Diagenetic Environments. Understandably, most of the papers were primarily oriented to carbonate petrologists, but several should be of considerable interest to PALAIOS readers for specific new data, for techniques, and for some significant theoretical implications. In the 'specific new data' category, algae were implicated as catalysts of some rather esoteric cements in two different Caribbean habitats. Brian Jones (University of Alberta) documented evidence that algae, fungi and lichen promoted the formation of 'lichen stromatolites' and microdendritic calcite growths in sinkholes on exposures of the Bluff Dolomite (Oligocene to Miocene) on Grand Cayman Island. John Kaldi (Shell Canada Limited) illustrated how algal filaments in beachrock pores of northern Jamaica have promoted the formation of low-magnesian meniscus cements by trapping fine detritus and retaining droplets of marine water in intergranular spaces.