The tectonic evolution and accumulation controlling characteristics of the middle fault depress belt of Hailaer-Tamtsag basin

摘要

The oil and gas resources is rich in the middle fault depress belt of Hailaer-Tamtsag basin.In recent years,gradually exploration success shows that the exploration potential of structural belt.But under the control of the complex tectonic and sedimentary evolution,hydrocarbon accumulation and distribution regularity needs further research.Using simulation of balance section the middle fault depress belt,combined with filling characteristics and superposition characteristics of basin that makes clear about the middle fault depress belt evolution process and the structural of rich oil forming process in the different tectonic evolution stages,and its control action of hydrocarbon accumulation.The study shows that the Hailaer-Tamtsag basin be made up with residual basin(under Tongbomiao Formation)and passive rift basin(Nantun formation-the late of Qinyuangang formation),superposition of two different nature of the basin.In this paper,we further be divided the passive rift basin into four evolution stages:Lower member of Nantun 1 formation-member of Nantun 1 formation,initial weak fault depression period;upper member of Nantun 1 formation-Nantun 2 formation,strongly fault depression period;Damoguaihe formation-Yimin formation,fault depression-depression transformation period;Qinyuangang formation-Now,depression period;Complex tectonic evolution process controling the three types of oil and gas accumulation zone development of the middle fault depress belt: overturned structure belU central anticlinal belt or central uplift belt and tilted uplift beInversion structure belt controls the upper oil gas bearing system,formation of the fault depression-depression transformation period.Central anticlinal belt or central uplift belt controls the middle oil gas bearing system,formation of the strongly fault depression period.Tilted uplift belt controls the lower oil gas bearing system,formation of the initial weak faulted period.