Volatile fluid overpressure in layered intrusions and the formation of potholes
Volatile fluid overpressure in layered intrusions and the formation of potholes
复制标题
层状侵入体中的挥发性流体超压和坑洞的形成
DOI：
10.1080/08120099208728023
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发表时间：
1992
影响因子：
1.2
通讯作者：
A. Boudreau
中科院分区：
文献类型：
--
作者：
A. Boudreau
层状侵入体中发育的坑洞在形态上与被称为麻点的沉积特征相似。通过与麻点形成理论的类比，认为当凝固层间液体分离出富挥发分的流体相时，坑洞区域下方的堆积段产生了显著的超压。当流体从积云间液体中分离出来的速度快于流体从晶体堆中逸出的速度时，就会形成流体超压。孔隙压力的增加表现为洞底和晶体堆最上面的圆顶状肿胀，最终破裂并导致流体猛烈逃逸。堆积物的流态化和不一致熔融的结合导致了孔洞的形成，这是由于挥发性元素加入到演化较少的液体和晶体组合中而导致液相线温度降低而造成的。S认为，过多的硫化物沉淀应伴随着流液混合事件.
Potholes that develop in layered intrusions show morphologic similarities with sedimentary features known as pockmarks. By analogy with pockmark formation theory, it is suggested that the cumulate section below the pothole region develops significant overpressures as solidifying intercumulus liquid separates a volatile‐rich fluid phase. A fluid overpressure develops as fluid separates from the intercumulus liquid faster than the fluid can escape from the crystal pile. The increase in pore pressure expresses itself as a dome‐shaped swelling on the chamber floor and in the uppermost part of the crystal pile, which eventually fractures and results in the violent escape of fluid. The combination of fluidization of the cumulates and incongruent melting, caused by the depression of liquidus temperature as a result of volatile elements added to less evolved liquid and crystal assemblages, leads to the formation of the pothole. Excess sulphide precipitation should accompany the fluid‐liquid mixing event as S‐bear...