Case history of complex-fracture behavior in the Hanoi Trough, Vietnam

In this paper we present a detailed case history of complex fracture behavi or in exploratory wells in the Hanoi Trough, Vietnam. The target formations are stacked fluvial channel deposits that occur at depths of 10,000 to 12, 000 ft. The initial three wells were drilled from the same pad, with bottom hole locations about 3,000 to 5,000 ft apart and a probable fault between t he No. 1 and No. 3 well. The gas reservoirs encountered were slightly overp ressured and varied significantly in quality, with permeability ranging fro m 0.01 to 1 md. The first three wells were fracture stimulated in an attemp t to improve deliverability. However, only one of the three treatments was successful due to complex fracture behavior. A comprehensive data set consi sting of core analysis, rock mechanical tests, pre- and post-fracture logs, geochemical analyses, pre- and post-fracture well tests, and detailed frac ture modeling was compiled to understand fracture performance in this compl ex environment. Without such a complete data set, identifying the cause of the treatment failures would probably not have been possible.