A typical sedimentary cycle of the Gulf Coastal Eocene consists of cross-bedded sands, well bedded sands, silty brown shale, unctuous brown shale, glauconitic brown shale, massive glauconite marl, gray calcareous shale, impure limestone, gray calcareous shale, unctuous brown shale, silty brown shale, well bedded sands, and cross-bedded sands listed in ascending order. Cycles of this type are rarely complete, most of them are broken or interrupted by disconformities. Most of the disconformities occur either at the base of the cross-bedded sands at the beginning of the cycle (regressional hiatus) or at the base of the massive glauconite marl (transgressional hiatus). The positions of the disconformities in the stratigraphic section of eastern and central Texas are shown. Th magnitude of the hiatuses is estimated with the aid of new methods.

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