Abstract: Tectono-Stratigraphic Interpretation, DBSG-114, Delaware Basin

Richard J. Erdlac Jr., Douglas B. Swift, James J. Reeves

Reprocessing and seismic sequence interpretation of Delaware Basin Group Shoot Line 114 suggests a complex interacting stratigraphic and tectonic history within the Delaware Basin and its margins. A total of 43 sequence stratigraphic intervals have been identified along a 30 mile portion of 114 made available for investigation. Considerable lateral stratigraphic variation was observed along the profile. Clastic sequence packages interfinger locally with other sediments, being shed basinward from both the Diablo and Central Basin Platforms. Numerous sequences thus display nondepositional or erosional hiatuses. Local channels or lensoidal-like reflection configurations are present throughout the section, from Rustler through Lower Pennsylvanian Formations. These features ar predominant within the deeper parts of the Basin and decrease in number towards the basin margins. Only one such body was encountered on the Diablo Platform whereas over two dozen were observed within the basin proper. These features may represent clastic and/or carbonate debris flows which moved laterally away from the basin margins to eventually flow parallel to the basin axis. Variations in amplitude and reflection continuity suggest lateral changes in rock type from shaly to more sand or carbonate rich lithologies. This interpretation is locally supported by well and sample logs which reflect this lithologic variation. Evidence for Permian-Pennsylvanian and older pre-Woodford tectonic activity is also suggested across the entire Delaware Basin from the stratigraphic intervals affect d by faulting. High and low-angle reverse and up-to-the-basin faults strongly suggest a tectonic event of about pre-Woodford age. Some of these faults may have been reactivated during the major Permo-Penn tectonic event which deformed the Permian Basin. Understanding the complex tectono-stratigraphic history of the region may be the key to unlocking new, undiscovered domestic oil and gas reserves within the Delaware Basin.

AAPG Search and Discovery Article #90960©1995 AAPG Southwest Section Meeting, Dallas, Texas