石油与天然气地质 ›› 2011, Vol. 32 ›› Issue (4): 506-511，521.doi: 10.11743/ogg20110403

• 石油与天然气地质 • 上一篇    下一篇

塔里木盆地大理岩化储层发育特征

  

  • 出版日期:2011-08-28 发布日期:2011-09-26

Characteristics of marmorized reservoirs in the Tarim Basin

  • Online:2011-08-28 Published:2011-09-26

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570

被引次数

11

摘要：

摘要：在岩浆侵入体热作用下，塔里木盆地下古生界碳酸盐岩局部发生了大理岩化作用。塔里木盆地西北缘巴楚县的塘王城剖面是大理岩化作用较为典型的野外剖面，塔中地区的中16井是揭示大理岩化作用较为典型的钻井。大理岩化特征随碳酸盐岩距离岩浆侵入体的远近不同呈现出规律性的变化。距离侵入岩体越近，大理岩颗粒越粗；而随着距侵入岩体距离增加，大理岩化程度逐渐降低，并逐步消失。碳酸盐岩发生大理岩化后的颗粒呈近似六边形的嵌晶状结构，次生孔隙空间较不发育。与灰岩原岩相比，大理岩化碳酸盐岩具有相似的锶同位素组成和较轻的碳氧同位素组成，由此表明大理岩化作用是热变质作用为主的过程；在此过程中，除原岩地层中少量地层水参与外，没有外来流体的参与。由于缺少外来流体的溶蚀作用，大理岩化储层物性与灰岩原岩相比没有明显的变化，而是继承了灰岩原岩的孔渗特征。

关键词: 关键词：大理岩化作用, 碳酸盐岩, 同位素, 储层, 塔里木盆地

Abstract:

Abstract: The Lower Paleozoic carbonates of Tarim Basin were marbleized locally due to the thermal effects of magma intrusions. Marmorization is typical on the Tangwangcheng outcrop section in Bachu county at the northwestern margin of Tarim Basin and in cores from Well Zhong-16 in the Tazhong area. The characteristics of marmorization change regularly with the distance from carbonate rocks to intrusions. The degree of marmorization is high in the periphery of igneous intrusions with grains of marble being relatively coarse, but is progressively lowers and eventually disappears away from the intrusions. Grains of carbonate experienced marmorization show pseudo-hexagonal poikilitic structure with poorly developed secondary pores. Compared with the unaltered limestone, the marmorized carbonates have similar strontium isotope composition but slighter oxygen and carbon isotope compositions, indicating that the marmorization is a process dominated by thermal metamorphism. During this process, no extraneous fluids except for a small amount of formation water in the original carbonates are involved. The quality of marmorized reservoirs is basically similar with the unaltered limestone due to the absence of dissolution from extraneous fluids.

Key words:  , Key words： marmorization, carbonate rock, isotope, reservoir, Tarim Basin