Global changes in sea level, primarily the results of tectonism and glaciation, control deep-sea sedimentation. During periods of low sea level the frequency of turbidity currents is greatly increased. Episodes of low sea level also cause vigorous bottom currents (i.e., contour currents) which winnow away the fine-grained material of turbidites. In the rock record, the occurrence of most

Figure

turbidites and winnowed turbidites closely corresponds to lowstands of paleo-sea level. For example, plotting of all known winnowed turbidites on the global sea level curve indicates that 19 of 20 examples fall on or near lowstands.

An important exploration attribute of these observations is the possibility of predicting the occurrence of potential deep-sea reservoir facies in the geologic record by using seismic data in conjunction with information on global sea-level changes, basin geometry, and paleo-oceanography.

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