Slab variations enhanced by oblique subduction along the convergent margin in Myanmar

Using the thermomechanical model developed from Stag3D code and the finite difference method (FDM), we constructed a 3D thermomechanical subduction model to explore the thermal variation and petrological metamorphic changes beneath Myanmar. An anelastic liquid approximation and the equations of conservation of mass, momentum, and energy are used. The model involves 3D geometric data for the incoming plate updated through seismology (Slab2) and real subduction velocities from the MORVEL datasets. The bottom of the slab and perpendicular plane are adiabatic and permeable, respectively, and the top surface is assumed to be rigid at a fixed temperature (0 °C). The trenchward temperature boundary follows a plate cooling model, and the plate ages are provided by EarthByte.

本研究采用基于Stag3D代码与有限差分法（FDM）开发的热机械模型，构建了三维热机械俯冲模型，以探究缅甸下方的热演化过程与岩石学变质变化。模型采用非弹性流体近似，结合质量、动量与能量守恒方程。所用数据包含通过地震学（Slab2）更新的俯冲板块三维几何数据，以及来自MORVEL数据集的实际俯冲速率。模型中，板片底部与垂直平面分别设置为绝热边界与透水边界，顶面被假定为固定温度（0℃）的刚性边界；向海沟方向的温度边界遵循板块冷却模型，板块年龄数据由EarthByte提供。