羌塘盆地及周边地带地球物理场与油气深部构造背景初探

THE PRELIMINARY STUDY OF GEOPHYSICAL FIELD AND DEEP STRUCTRAL BACKGROUND OF OIL AND GAS FOR QIANGTANG BASIN AND ITS NEIDHBOURING REGIONS

本文对已有的地球物理场资料、地壳与上地幔结构的概略展布以及青藏高原的大地构造格局进行了综合分析。结果表明：该区沉积层巨厚，重力场表现为负异常，地壳底部与上地幔顶部相对周边造山带上隆，低速异常分布，地幔对流向生此向下聚集．这些要素提出：羌塘盆地具有构成新油气田的深部构造背景和地球物理场特征。基于这些初步认识。

Qinghai-Xizang Plateau, which has great thickness Mesozoic and Cenozoic sedimentary formation, is a special geotectonics environment formed under the cooperations of its aroud plates. This paper discusses whether the plateau, especially Qiangtang basin, reserve rich oil ang gas. According to the known geophysical data and sketchy distribution of crust and upper mantle structure and combining with Qinghai- Xizang geotectonics framework, we have made synthetical studies for Qiangtang basin. The study shows that this zone has great thicknese sedimentary and negative gravity anomaly, the lower crust and upper mantle have low velocity anomaly compared with aroud orogenic belt and mantle conviction accumulate down here. The above faters reveal that Qiangtang basin has the geophysical field chatarter and deep structral background for the formation of new oil or gas field. Based on this primary recognition,we Finally give some suggestions for the further study on Qiangtang hasin.