RSQSim_v0

Description

<h2> RSQSim basics </h2>

<p> RSQSim is a 3D boundary element code which relies on the rate and state friction formulation to generate synthetic earthquake catalogs. RSQSim utilizes quasi-static stress interactions between adjacent fault elements and discrete element states to speed up the computation. It assumes steady-state during the interseismic period , which allows for an analytical solution for time to failure, which allows for skipping inter-event time-stepping. During the coseismic period, the elastodynamics are grossly approximated by reducing the rate coefficient a to weaken adjacent fault elements and introducing a parameter for dynamic overshoot.

<h3>Input Data & Fault File Formatting</h3>

<h4>1. Quad (Rectangular) Elements</h4> <p><em>Schema:</em> <code>x y z l w strike dip rake sliprate section_number section_name</code></p> <ul> <li><strong>x, y, z:</strong> Coordinates of the center of the fault patch (in meters).</li> <li><strong>l, w:</strong> The along-strike and down-dip dimensions of the patch (in meters).</li> <li><strong>strike, dip:</strong> Orientation of the fault patch in degrees, adhering to the Aki and Richards (2002) convention.</li> <li><strong>rake:</strong> Direction of motion of the hanging wall relative to the footwall in degrees (Aki and Richards, 2002 convention).</li> <li><strong>sliprate:</strong> Long-term average slip rate (in m/s).</li></ul> <h4>2. Triangular Elements</h4> <p><em>Schema:</em> <code>x1 y1 z1 x2 y2 z2 x3 y3 z3 rake sliprate section_number section_name</code></p> <ul> <li><strong>x1 y1 z1 to x3 y3 z3:</strong> Explicit 3D coordinates for the three vertices of the triangular element.</li> <li><strong>Ordering Rule:</strong> Vertices must be ordered according to the <strong>right-hand rule</strong> such that they produce an upward-facing normal vector for dipping faults.</li><li><strong>rake / sliprate:</strong> Consistent with the quad format definitions above.</li> </ul>