bcross

代码说明：

  将断层剖面划分为一组网格，并以固定的事件数或固定的扫描半径，计算每个网格点处的b值。然后用色彩表示断层面上b值的分布情况，从而反应断层的应力积累情况，便于地震学家分析该断层是否存在发震的可能(This subroutine creates a grid with spacing dx,dy (in degreees). The size will be selected interactively or grids the entire cross section. The b-value in each volume is computed around a grid point containing ni earthquakes or in between a certain radius. The standard deviation is calcualted either with the max. likelihood or by bootstrapping, when that box is checked. If not, both options can be assigned by the additional run assignment. Standard deviation of b-value in non-bootstrapping case is calculated from Aki-formula!)