The potential of deep natural gas resources is great at the northern margin of Qaidam Basin

but it is lower in exploration maturity.The gas accumulation conditions and plays for exploration are still to be revealed

restricting the exploration progress of natural gas.Given studies on seismic

geological

geochemical and drilling data

we analyzed the conditions for gas accumulation in deep strata at the northern margin of Qaidam Basin comprehensively in terms of source rock

reservoir

structure

and carrier system

and pointed out the favorable plays for deep gas exploration based on the existing exploration results and geological conditions.The results show that due to the widespread distribution of the Jurassic

a new Jurassic hydrocarbon generation depression is discovered in the western segment of the piedmont of Altun Mountain

featuring high potential of hydrocarbon generation in the deep high-to-over-mature source rocks.Both the weathering crust of bedrocks and clastic rocks with well-developed secondary pores may serve as the effective reservoirs in deep horizons:the physical properties of the former are not controlled by depth

and the latter were well developed characterized by high quality in deep horizons.The fracture-dominated carrier system of wide distribution is conducive to the vertical and horizontal migration of natural gas generated from ultra-deep source rocks.Multi-stage tectonic activities have led to the formation of multiple types of traps in deep layers at the northern margin of Qaidam Basin; meanwhile the continuous hydrocarbon generation of source rocks have facilitated the earlier

multi-stage hydrocarbon accumulation in these deep traps.In view of the above results

it is concluded that the traps around the hydrocarbon generation sag with well-developed deep large faults are favorable for deep gas accumulation

and the paleo-uplift at the basin margin and the large-scale anticlinal traps in the late tectonic zone are prospective areas for hydrocarbon exploration

with the deep layers in the piedmont of the Altun Mountain being the most prospective one.