综合物化探技术在柴达木盆地的应用

Application of Integrated Geophysical and Geochemical Exploration Techniques in Qaidam Basin

应用综合物化探技术从地球物理场方面揭示了柴达木盆地具有双重基底结构,上部为褶皱基底,深部存在结晶基底,该基底的厚度变化控制着盆地的隆凹格局;褶皱基底岩性具有明显的分区性,不同分区的基底岩性差异较大,从而造成不同分区具有不同的变形特征,这种分区性受深部结构断裂控制。山前带是柴达木盆地油气勘探的重要领域,但由于复杂的地形地质条件,很多认识具有局限性。综合勘探在山前带的应用基本明确了山前带的构造特征,发现了一些山前凹陷和逆掩推覆区,拓宽了柴达木盆地的勘探领域。

From the perspective of geophysical field, applied integrated geophysical and geochemical exploration techniques reveal that Qaidam Basin has double basement structures. The upper is the folded basement and the crystallized basement exists in the deep part. The thickness variation of the crystallized basement controls the upwarping- downwarping pattern of the basin. The folded basement lithology has obvious zoning characteristics and it varies a lot in different zones. As a result, different zones have different deformed characteristics. The zonality is determined by the fracture of deep structure. The front belt of mountain is an important area for oil and gas exploration in Qaidam Basin, however, there are still a lot of limitations on the cognition of it due to its sophisticated topographic and geological conditions. The structural characteristics of the foothill belt have been basically known, some piedmont depressions and overthrust nappe zones have been discovered, and the exploration area of Qaidam Basin has been widened as well on the basis of the application of the integrated geophysical and geochemical exploration techniques.