关键词: 准噶尔盆地, 全油气系统, 煤层气, 页岩气, 致密气, 深层—超深层, 勘探方向

Abstract: Junggar Basin is rich in oil-gas resources. There are three sets of major source rocks of Carboniferous System, Permian System and Jurassic System. There are diverse types of reservoirs, including volcanic rock, conglomerate, sandstone and carbonate-type mixed rock. Among them, conglomerates distributed at the edges and slopes of hydrocarbon-rich sags in the basin are the main body for increasing reserves. There are three sets of regional mudstone cap rocks distributed in the basin, which are vertically stacked with the reservoir, thus dividing the basin into a three-decker structure and forming three major petroleum systems, i.e., the Carboniferous, Permian and Jurassic petroleum system. In recent years, through innovating geological understandings, highlighting risk exploration, strengthening intensive exploration and fine exploration, and exploring the sag center and source rocks, Junggar Basin has achieved substantial achievements in the exploration of deep and ultra-deep fields. Particularly, focusing on "new areas, new fields, new strata and new types", based on previous research work, a deep analysis is performed on accumulation conditions for petroleum systems, and efforts are made to innovate the understandings of hydrocarbon accumulation, involving "whole petroleum system", "coalbed methane from other source rocks", "Carboniferous self-generation and self-reservoir and new generating hydrocarbon in paleo-reservoir". Therefore, four important new breakthroughs have been made as below:natural gas of lower assemble in the southern margin thrust belt, whole petroleum system in Fengcheng Formation in the western depression, paleo-uplift around the hydrocarbon-rich sag, and Jurassic coalbed methane in the basin. Future exploration directions and key areas are pointed out by systematically summarizing recent exploration achievements, and comprehensively analyzing the characteristics of the field. It has been clarified that the basin should adhere to the comprehensive exploration idea of "equal emphasis on both conventional and unconventional resources, collaborative development of oil and gas, and whole petroleum system" in the future, focusing on the further exploration of natural gas of the southern middle-lower assemblage, deep/ultra-deep conventional structural trap and unconventional light hydrocarbons in the western depression, and Jurassic coalbed methane.

Key words: Junggar Basin, whole petroleum system, coalbed methane, shale gas, tight gas, deep and ultra-deep strata, exploration direction