About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

GCAGS Transactions


Gulf Coast Association of Geological Societies Transactions
Vol. 19 (1969), Pages 489-501

The Subsurface Frio of South Texas: Stratigraphy and Depositional Environments as Related to the Occurrence of Hydrocarbons (1)

Gene B. Martin


An interpretation of depositional environments and a general depositional history of the subsurface Frio in South Texas is presented.

In the South Texas subsurface Frio the reservoir rocks appear to be very closely related to deltaic environments. In the updip Frio the hydrocarbons are found mainly in alternating deposits of:

  1. Non-marine environments (including deltaic plain, distributary, alluvial, and lacustrine).
  2. Coastal environments (including brackish water bays, beach, inter-distributary, and delta-front).

In the downdip Frio the hydrocarbons are found mainly in alternating deposits of:

  1. Inner-neritic environments (including open ocean beach, some brackish water, and delta-front).
  2. Middle-neritic environments (mainly pro-delta).

The subsurface Frio is believed to be the equivalent of the Bucatunna and upper and lower Chickasawhay Formations that are exposed in Mississippi and Alabama.

Evidence is presented to indicate that source beds and reservoir rocks may be one and the same, or at least a very close relationship exists, and that there has not been any appreciable long-distance migration of hydrocarbons.

The importance of the documentation of the depositional environment of mineral bearing sediments is stressed.

Pay-Per-View Purchase Options

The article is available through a document delivery service. Explain these Purchase Options.

Watermarked PDF Document: $14
Open PDF Document: $24