ABSTRACT: Geophysical Evaluation of the Yacheng 13-1 Natural Gas Field, People's Republic of China
Barry M. Davis, Andrew C. Selby
The Yacheng 13-1 natural gas field was discovered by ARCO China in 1983 with the drilling of the Yacheng 13-1-1 well. Since that time an additional 5 wells have been drilled to define the field. Current mapping of the field indicates there are 3299 BCF gas-in-place in the main reservoir.
Geophysics have been central in the process of assessing field reserves. It has been critical in the structural mapping of the field, as well as defining the stratigraphic character and elements of the reservoir. The 2-D seismic acquired in 1979, 1983, 1984, and 1985 provide a 1 km grid of data. This grid has been sufficient to characterize the field in a gross sense; however, only with the use of state-of-the-art processing methods has ARCO China been able to maximize the benefit of these data in assessing the reservoir distribution, gas/fluid contacts and well information.
In 1989, ARCO reprocessed all of the seismic lines over the field using the Pre-Stack F/K Migration technique. This improved the structural image and the resolution of stratigraphic elements. From these improvements, a better understanding of the relationship between faulting and basin depositional history and hydrocarbon contacts within the 13-1 Sand member has resulted. Furthermore, their reprocessing has allowed detailed mapping of additional potential reservoirs within the overlying wedge member.
AAPG Search and Discovery Article #90097©1990 Fifth Circum-Pacific Energy and Mineral Resources Conference, Honolulu, Hawaii, July 29-August 3, 1990