Abstract:

In order to guide the exploration of saline basin from Palaeogene to Neogene in western Qaidam Basin, models of sands control and enrichment in saline basin were constructed, combining with field study of modern saline basin sedimentary characteristics of Qinghai lake. Delta sedimentary simulating experiment in salt water medium was carried out. The research results of delta sedimentary simulating experiment in salt water medium indicated that the sedimentary facies of saline basin delta is mainly composed by plain facies, accounting for over 80% of the entire delta area, and mouth bar microfacies in the delta front sub-facies is the most developed. The results show that the saline water medium controls the distance of transportation of various granularities, contrasting with water medium which less saline, fine-grained sediments in saline water were rapidly deposited in the mouth of river, and the coarse sediments transported farther, the sedimentary range were also more larger. The results indicate that saline basin delta sediment developed sand body architecture of river-over-bar sand body, on the longitudinal. Delta sedimentary simulating experiment defines the distribution characteristic of reservoir, enlarges the range of reservoir, and provides a technical support on oil-gas exploration in western Qaidam Basin.

Key words: sedimentary simulation, saline basin, delta, sedimentary feature, Qaidam Basin