火成岩侵入形成的构造物理模拟实验

The physical modeling on the structures resulted by igneous rock irruption

在上覆地层为横向均质的情况下完成了火成岩侵入形成特殊构造的物理模拟实验。结果表明,在侵入过程中,岩浆向正上方呈蛇曲状盘旋上升,顶部构造呈圆形或近圆形拱起,拱起边界为封闭型断层。岩浆侵入脆性地层时表现为应力积聚与释放的交替,具脉动跳跃现象,岩浆通道形状不规则;岩浆侵入塑性地层时应力变化平稳,岩浆通道向四周扩张,顶部地层构造形态具继承性。实验过程很好地解释了济阳坳陷SH24构造的形成发育机制。实验成果填补了国内火成岩侵入构造物理模拟的空白,为今后类似实验提供了借鉴。

The physical modeling on the structures resulted by igneous rock irruption was taken under the condition of horizontal isotropic medium as overlying formation. The results showed that the magma spiraled up during the irruption , many closed faults were formed at the edge of arch. The stress accumulated and released alternatively when it irrupted into brittleness formations and magma conduit formed irregularly. The stress changed steadily when it goes into plasticity formation, the magma conduit expanded around, the shape of the structures on top was of inheritance. The experiment process revealed the development mechanism of the structure SH24, Jiyang Depression filled in gaps in the fields of the physical modeling on the structures resulted by igneous rock irruption.