Arthur N. Palmer, 1995. "Geochemical Models for the Origin of Macroscopic Solution Porosity in Carbonate Rocks", Unconformities and Porosity in Carbonate Strata, David A. Budd, Arthur H. Saller, Paul M. Harris
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Any single geologic setting may include a variety of geochemical environments, each capable of producing a different type of carbonate solution porosity Also, many types of porosity can form in more than one geologic setting. Thus, the interpretation of solution porosity is best approached by first delineating the geochemical processes necessary to form the observed pattern of porosity, and then using these insights to assess the broader geologic context. Throughout most of any carbonate formation the solution process is highly selective, and only those openings of maximum groundwater flow are enlarged, while surrounding openings undergo little or no enlargement. Pervasive macroscopic porosity, in which nearly all initial openings are enlarged by solution, is formed by: (1) meteoric water with high discharge and/or low flow distance, (2) mixing of waters of disparate chemistry, (3) oxidation of hydrogen sulfide, or (4) production of acids by redox reactions involving carbon compounds in reducing environments. Areally extensive solution porosity within a narrow stratigraphic range usually indicates solution or reduction of sulfates. Cavernous solution porosity is negligible where aggressive infiltration is lacking, in deep zones where groundwater chemistry is uniform, and in low-flow areas of diagenetically mature carbonate rocks far from sources of groundwater recharge.
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Looking for insights and methods useful for predicting and identifying subaerial exposure surfaces and associated porosity? This memoir addresses four major topics: Detection of unconformities; Modification of porosity during exposure; Preservation of porosity during burial; and Influence of unconformities on subsequent depositional and diagenetic patterns.