Abstract:

Exploration and development activities in Tahe oilfield indicate that the Triassic targets are characte-rized by great burial depth and low amplitude of local structures.Its traps are mainly of subtle types,including low amplitude structure,lithologic structures,and lithologic-structural combination traps.This paper puts forward ways of identification and evaluation of non-structural traps based on the experiences of exploration in the Triassic strata.Favorable oil an gas plays are firstly located through an all-round,dynamic,and comprehensive regio-nal study;then,seismic identification and evaluation techniques of non-structural traps with amplitude extraction as the core are developed based on study of sequence stratigraphy to locate and identify favorable non-structural traps in Tahe oilfield;and finally,trap evaluation is performed by using the technology of seismic hydrocarbon detection.A rational combination of the above-mentioned methods may be a effective way to reduce exploration risks and improve success rate.

Key words: lithologic trap, combination trap, seismic prediction technique, identification and evaluation of non-structural traps, Triassic, Tahe oilfield