费尔干纳盆地巴特肯地区混合沉积的特征及成因

 综合应用岩心、测录井、铸体薄片、扫描电镜等多种资料及测试手段，对中亚费尔干纳盆地巴特肯地区白垩系-古近系混合沉积特征进行研究，分析混合沉积成因，并探索混合沉积与油气的关系。结果表明，费尔干纳盆地巴特肯地区白垩系-古近系发育的混合沉积，包括混积岩和混积层系两种形式，其中，混积岩主要为含陆源碎屑-碳酸盐岩和陆源碎屑质-碳酸盐岩，混积层系主要为碳酸盐岩-混积岩层系和陆源碎屑岩-混积岩层系；混合沉积在巴特肯地区分布十分广泛，局限台地相、蒸发台地相、障壁海岸相和浅海陆棚相均有分布；混合沉积成因主要为相缘混合，其次为原地混合和间断混合；混合沉积在烃源层、储集层和盖层三方面均具有一定贡献，古近系泥灰岩是巴特肯地区主要的烃源岩之一，同时也可作为区域性盖层，而白垩系-古近系灰岩储集层也并非严格意义上的纯碳酸盐岩，多为混积岩或混积层系中的一部分。

Characteristics and origins of mixed sediments in Batken region of Fergana basin

By means of various data and measurements such as rock cores, well logging, mud logging, cast thin-sections and scanning electron microscope, this paper investigates the characteristics and origins of mixed sediments and their relation with petroleum-gas resources from Cretaceous-Paleocene in Batken region of Fergana basin in the central Asia. It is considered that mixed sediments from Cretaceous-Paleocene in the research area developed with two forms:mixed rocks and mixed layer series. The mixed rocks are dominantly terrigenous clastic bearing-carbonate rock and terrigenous clastithic-carbonate rock. And the mixed layer series are mainly carbonate rockmixed rock layer series and terrigenous clastic rock-mixed rock layer series. The mixed sediments in the research area are widely distributed in various environments, including restricted platform, evaporated platform, barrier coast and neritic shelf. Furthermore, the main origin of the mixed sediments is facies mixing, followed by in situ mixing and punctuated mixing. In addition, the mixed sediments in the research area made some contribution to source-reservoir-cap rocks. To be more specific, the marlite of Paleocene is one of the main source rocks as well as regional cap rocks for the research area. Besides, the limestone reservoirs of Paleogene and Cretaceous are not pure carbonate rocks. Instead, most of them are mixed rocks or part of the mixed layer series.