权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

RETROLOGICAL STUDY OF THE BILIBILI ALKALI LAYERED INTRUSION

哔哩哔哩碱层状入侵的追溯研究

基本信息

批准号：
09640574
负责人：
NISHIYAMA Tadao
金额：
$ 1.92万
依托单位：
KUMAMOTO UNIVERSITY (1998)Kyushu University (1997)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1998
项目状态：
已结题

项目摘要

This project carried out the investigation of the occurrence of the BiliBili alkali layered intrusion in the south of Sulawesi island, Indonesia, and examines the origin of the layered structures, leading to the following conclusions.(1) There are 197 layers within 120 meters from the contact between the intrusion and the surrounding Chamba Formation of the Miocene. The thickness of the layer increases systematically towards the interior of the intrusion. The systematics obeys the Spacing Law similar to that of the Liesegang Rings.(2) A layer consists of a hard part rich in Na2O and a soft part rich in K20.(3) Overall chemical variation of the intrusion based on the bulk rock chemistries of randomlly collected 24 samples is almost similar to that within a single layer. Thus chemical differentiation occurred during the layer formation by solidification of a homogeneous magma.(4) A physical model is proposed for the layer formation such that the layer represent a eutectic mushy layer where the interplay of the layer front (high temperature side of the layer) and the solidification front (low temperature side) casuses a periodical growth and solidification of the layer. Chemical differentiation within a layer was caused by mass transfer associated with heat transfer. The Spacing Law can be explained by the growth of solidified part which prevents an efficient heat loss from the intrusion that influences the thickness of the layer.

该项目对印度尼西亚苏拉威西岛南部BiliBili碱性层状侵入体的发生进行了调查，并检查了层状结构的起源，得出了以下结论。(1)岩体与周围中新世昌巴组接触面120米范围内有197层。该层的厚度朝向侵入体的内部系统地增加。系统学上遵循与Liesegang环相似的间距律。(2)层由富含Na2O的硬部分和富含K2O的软部分组成。(3)根据随机采集的24个样品的岩石化学成分，岩体的总体化学变化几乎与单层内的化学变化相似。因此，化学分异发生在层的形成过程中，由一个均匀的岩浆凝固。(4)提出了一个物理模型的层的形成，使层代表共晶糊状层的相互作用的层前（层的高温侧）和固化前（低温侧）的原因周期性的生长和固化的层。层内的化学差异是由与热传递相关的质量传递引起的。间距定律可以用凝固部分的生长来解释，凝固部分的生长阻止了影响层厚度的侵入的有效热损失。