The Flippen carbonate (Wolfcampian) was deposited during a high stillstand of sea level under subtidal to intertidal conditions. Eleven cores in Fisher and Jones Counties have been subjected to megascopic and petrographic analysis with special interest given to the Alkali Creek SW field in Fisher County. Five distinctive limestone facies, designated according to their most outstanding characteristics are: (1) constructional phylloid algal buildups, (2) crestal boundstones, (3) flanking bed packstone-wackestone, (4) foremound pelloidal grainstone, and (5) capping grainstones.

Early diagenesis occurred after deposition of the sediments in the marine environment. This is evident in micritization, submarine cements, and effects attributed to binding and encrusting habits of algae, particularly Archaeolithoporella and Tubiphytes.

Primary intergranular and intrabiotic porosity is best developed and preserved in biograinstones along the shallow flanks of the constructional mound. Stabilization and lithification of originally deposited sediments began early during subaerial exposure and subsequent freshwater diagenesis. Secondary porosity was formed by the dissolution of aragonitic phylloid algae and pelecypods, forming hollow micrite envelopes or biomolds. Aragonitic lime mud was replaced by calcite micrite and microspar. Calcitization and dissolution resulted in the precipitation of crusts of calcite scalenohedra in primary and secondary voids. Dolomite cement crusts also line primary and secondary voids, and these rhombs subsequently were dedolomitized. Precipitation of blocky equant nonferroan calcite, ferroan calcite, and ferroan dolomite cements partially to completely filled primary and secondary voids. A late stage of dissolution, which presumably occurred at depth, enhanced existing primary and secondary porosity. No cementation followed the late stage of diagenesis.

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