深层火成岩侵入体和相关构造发育特征及其石油地质意义——以塔里木盆地顺北地区为例

Characterization and petroleum geological significance of deep igneous intrusions and related structures in the Shunbei area， Tarim Basin

刘雨晴 邓尚 张荣 刘军 黄诚 高天

Yuqing Liu Shang Deng Rong Zhang Jun Liu Cheng Huang Tian Gao

为加深对塔里木盆地顺北地区岩浆侵入作用的研究，运用研究区丰富的三维地震资料，在详细刻画火成岩侵入体及相关构造发育特征和展布规律的基础上，建立了岩浆的垂向侵入模式，确立了岩浆的侧向流动方向，探讨了其石油地质意义。结果表明，顺北地区的碟形火成岩侵入体一般沿中、下奥陶统顶界面及以上界面层状叠置分布，碟形岩床之上发育逆断层和高陡裂隙两类构造，由此自下而上形成了“岩浆通道、叠置岩床、高陡构造”的岩浆垂向侵入模式。碟形岩床及相关构造的展布特征表明，该区岩浆自深部侵入到中、下奥陶统顶界面之后自北向南呈放射状侧向流动。研究火成岩侵入体对储层的改造作用和相关逆断层对油气的运聚作用有利于开拓顺北地区乃至整个塔里木盆地的油气勘探新领域。

The magma intrusion in the Shunbei area， Tarim Basin， is investigated based on newly acquired 3D seismic data. The igneous intrusions and related structures in the area are characterized and mapped in detail to establish a vertical intrusion model， determine lateral flow direction of magma， and reveal their petroleum significance. The igneous intrusions are saucer-shaped and distribute along the top boundary of the Lower-Middle Ordovician and the boundaries of strata above it in layered superimposition. Reverse faults and steep fractures occur above the saucer-shaped sills， leading to a vertical magma intrusion model of “magma pathway-superimposed sills-steep structure”. The actual distribution of the sills and related structures reveal that the magma in this area fisrt intruded from the deep to the top of the Middle-Lower Ordovician and then flew laterally from north to south in a radial pattern. All these suggest that igneous intrusions play a role in improving reservoir quality and the related reverse faults are the pathways for hydrocarbon to migrate. A deeper understanding of the sills and related structures can be a better guidance for oil and gas exploration in the Shunbei area or even the whole Tarim Basin.

10.11743/ogg20220109