层状侵入体的韵律层理成因

FORMATION OF THE RHYTHMIC LAYERING OF LAYERED INTRUSIONS

:层状侵入体的一个典型的特征是具有隐层理和韵律层理。分析比较了前人提出的韵律层理形成的各种机制并结合对攀枝花层状侵入体的研究认为 ,层状侵入体的韵律层理的形成与成岩的压实作用关系密切 ,细粒韵律层理是由于颗粒大小的微小差别或矿物成分含量的逐渐增加和重复的再平衡所致 ,矿物成分含量的逐渐增加和重复是通过在类似于奥斯特瓦尔德成熟的条件下循环溶解和晶体生长形成的。在影响层理形成的多种因素中 ,以对流作用、密度、粘度及岩浆房的几何形状等因素的研究较为详细 。

The cryptic layering and rhythmic layering are typical feature of layered intrusions. While the origin of layered intrusions varies a lot. In this paper, the rhythmic layering resulted from compaction-related processes was praised based on study of Panzhihua layered intrusion. Small difference of grain size and the re-equilibrium of variations of mineral content may cause the fine-scale cyclic layers. The cyclic solution and crystal growth during Ostwald ripening may have played a role in producing the increase and repetition of mineral content. Convection, density, viscous and shape of the magmatic chamber are main factors of the formatin of the rhythmic layering.