Abstract:

The Ordos Basin is being constructed into Chinas second Daqing oil field—“ShaanMeng Daqing”—based on the large Sulige gas field. The petroleum exploration in the Ordos Basin has experienced a complex and tortuous course. People have had doubts about petroleum prospects in this basin many times. No major advances had been made until a Triassic oil field was found in Qingyang in 1970 after nearly 30 years of probe. In 1988 the Lower Paleozoic Jingbian gas field was found and in 2000 the Su No. 6 well revealed the large Sugeli gas field; then great breakthroughs in petroleum exploration in the basin have been made step by step. This paper deals with the exploration course in Ordos and the relationship between the guiding ideas in various stages of the exploration and breakthroughs in the oil field, as well as their key links. The basic experience put forward is as follows: (1) we should continuously sum up and deepen our knowledge in practice, overcome the trammels of the idea of search for structural oil/gas reservoirs and understand the importance of lithologic oil/gas reservoirs; (2) at first Li Siguang emphasized the determination of the work direction on the basis of an allround study of the basin but then he emphasized search for oil/gas in areas without structures in the central part of the basin, implying that his analysis of the oil/gas reservoirforming conditions in the Ordos Basin overstepped the view of structural expulsion of oil and structural accumulation of oil and that he had got the new idea of looking for lithologic oil/gas reservoirs; and (3) three techniques should be stressed, i.e.，the highresolution seismic technique used to outline channel sand bodies, fracture pressure technique and advance water injection used for lowpermeability oil/gas reservoirs and the “five plus one” management model. The paper also proposes the work direction of expanding resources in the future.

Key words:  , Ordos Basin； Sulige； Li Siguang； lithologic gas reservoir； Changqing