ABSTRACT
Adjacent to the east and south boundaries of Wattenberg field, the lower Cretaceous D Sand is productive in an area that exhibits basin center, hydrocarbon saturated characteristics. In this geographic region, the D Sand produces from stratigraphically defined channel systems within the hydrocarbon saturated window. The key elements of D Sand exploration success in the hydrocarbon-saturated zone are identification of prospective channel trends and reservoir quality sandstone within the erosional channel. An estimated 240 MMBO and 570 BCFG have been produced from the D Sand in the D-J Basin since its discovery in 1930; approximately 24 MMBO and 133 BCFG have been produced from channel sandstones in the hydrocarbon-saturated zone.
Since 1993, HS Resources has acquired nine 3-D seismic surveys from T3N-R62W to T3S-R65W (Weld and Adams Counties, Colorado) totaling 114 square miles of data. The area of interest for HS Resources’ exploration activity was limited to that portion of the D-J Basin that lies within the hydrocarbon-saturated window. The company utilizes an integrated approach, combining geology, geophysics and reservoir engineering in its 3-D seismic exploration efforts. This approach to the D Sand Play has resulted in the discovery of the Spenson Field, and extensions of the Center Pivot and the Lanyard Fields.
The integration of the nine 3-D seismic surveys acquired over different play types within the D Sand play has provided the necessary prospect characteristics for an overall successful project. The utilization of 3-D seismic in combination with detailed regional mapping can significantly reduce the historically high risks of exploring for the D Sand. The result can be a profitable play for the small to mid size independent operator.