Twin Morrow Field; a case study

Upper Morrow sandstones in the Texas panhandle are often laterally discontinuous and small. Exploration and development of these sandstones can be precarious due to the rapid change from reservoir quality sandstone to shale. Successful incorporation of seismic data into reservoir delineation and characterization of the Upper Morrow sandstones could increase the success ratio and thereby enhance the economic feasibility of this type of exploration and development venture. Therefore, in 1989, Unocal shot a high resolution vibroseis line across Twin Morrow Field to analyze the seismic response of the productive Upper Morrow Sandstone, locally known as the Buckhaults Sandstone. The producing reservoir is an interpreted point bar deposit, three miles long and one mile wide with a maximum thickness of 55 ft. A reflector which is correlatable to the Buckhaults is present on the high resolution seismic data, but this sandstone is too thin for thickness resolution with current seismic methods.