准噶尔盆地北部古生代构造演化与石炭系烃源岩

The Paleozoic tectonic evolution and the Carboniferous source rocks in the northern Juggar Basin

在准噶尔北部地区断裂演化的基础上,将北部地区震旦纪—石炭纪的构造演化划分为两个阶段:①震旦纪—中奥陶世洋盆扩张阶段;②晚奥陶世—石炭纪洋盆俯冲、地体拼接阶段。石炭纪准噶尔盆地北部地区处于半深海-浅海、海-陆过渡环境,具备烃源岩发育条件。钻井和露头揭示,石炭系发育上、下石炭统两套烃源岩。油-源对比分析和构造演化研究表明,伦5井、滴北1井油气主要来源于乌伦古坳陷石炭系。

The tectonic evolution history of the Northern Junggar Basin from the Sinian to the Carboniferous can be divided into two stages based on study of its fault evolution. The first is ocean basin spreading stage from the Sinian to the Middle Ordovician and the second is ocean basin subduction and plate suturing stage from the Late Ordovician to the Carboniferous. During the Carboniferous, the northern Junggar Basin was in bathyal- shallow marine and ocean-continent transitional environments, and therefore was suitable for the development of source rocks. Drilling data and field outcrops reveal that there are two sets of source rocks developed in the Lower and Upper Carboniferous respectively. Oil-source correlation and tectonic evolution analysis suggest that the oil/gas of the Lun-5 and DB-1 wells are mainly derived from the Carboniferous source rocks in the Wulungu depression.