Hydrocarbon Forming Pattern And Favorable Block Prediction Of Putaohua Oil Layer In Yongle Syncline Area

Yongle syncline locates at Sanzhao Depression in the regional tectonic, Putaohua reservior is the most important oil layer in the study area of the lower part or mid section Oily portfolio. For a long time, the law of Putaohua accumulation isn't made clear. In the paper, applying the sedimentology, sequence stratigraphy, petroleum geology, and other disciplines theories and methods, palaeostructure of the study area, sequence stratigraphic framework, the accumulation stage of oil and gas reservoirs, water and oil distribution, trap type are studied in deep; the law of hydrocarbon accumulation and enrichment is summarized. The further direction and goals of exploration and development are pointed out. There is an important guiding significance of the causes and prediction is of reservoir of the entire Sanzhao depression.This paper begins with Sanzhao Depression and the surrounding ancient tectonic evolution. A fine study the ancient tectonic evolution of Yongle syncline is done. The four stages of tectonic evolution are summed up. On the basis of ancient structure research, by Putaohua stratigraphic thickness, Putaohua sandstone thickness, ancient geomorphologic features, and distribution of facies, sand /mud ratio analysis, the study area is the north of a single source. During Yongle syncline Putaohua the deposition, deposition mainly controlled by the northern delta large sedimentary system. Appling sedimentology, sequence stratigraphy theory , the Yongle oilfield Putaohua layer make the subtle stratigraphic division and contrast. A high-resolution sequence stratigraphic framework is established. Through highlight deposition time unit microfacies study in important area, it was found that the study area is delta front subfacies. The distributary channel, sand sheet is main reservoir. The distributary channel is very narrow, developed, and extends far. By Yongle and Xujiaweizi depression hydrocarbon source rocks buried history research, oil and gas primary migration period is the late Nenjiang Es4 group, the key period of migration of the oil and gas reservoir is the later Mingshui second member, and the oil and gas of field migration obtain a new understanding. On the basis of study area Putaohua structures, sandstone, static, dynamic, shooting a well and the oil-water interface research, the 10 typical single traps are analysis.accumulation model of Yongle syncline is summed up; 'single local structures' main controlling oil factors are pointed out. Under the guidance of the reservoir accumulation law, prediction of the development region surrounding area and favorable blank area are done.