Detailed studies of Cretaceous Edwards carbonate beaches revealed striking vertical sequences of first generation, early diagenetic fabrics which are thought to represent the diagenetic imprint of the original hydrologic regimen on the sediments during and soon after their deposition.

The classic environmental zones of the beach can be recognized in the Cretaceous prograding beach sequences and contain, from top to bottom, the following diagenetic features.

The backshore zone contains penecontemporaneous dolomite, dedolomite, montmorillonite-caliche paleosoil zones; all evidence points to a meteoric-vadose diagenetic environment.

The foreshore zone contains much moldic porosity, micrite rims on grains, beach rock cemented during deposition by metastable carbonates; all intragranular cements have a low iron content indicating an oxidizing vadose cementation environment. These features indicate the influence of both meteoric and marine hydrologic conditions.

The lower foreshore zone is characterized by dominant inversion textures preserving shell structure of original aragonite grains, the notably poor development of micrite rims, the presence of early metastable carbonate cementation (beach rock) and relatively high iron content of intragranular cements. These features indicate reducing phreatic, dominantly marine hydrologic conditions during diagenesis.

The offshore zone contains high iron intragranular cements, multiple bored, and inverted bored surfaces. The diagenetic environment was no doubt marine phreatic.

Companion studies of Holocene carbonate beach sediments, rocks, and interstitial water confirm to a remarkable degree, the diagenetic patterns found in the foreshore and upper offshore zones of the Edwards carbonate beaches, which lends strong support to the use of these patterns as a preliminary model of carbonate diagenesis in the beach environment.

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