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介绍了简单而又新颖的公式,使用微震的二分量,即圆形台阵记录的水平运动直接推断勒夫波相速度(cL)时,这些公式具有帮助作用。我们的公式与一般用于推断瑞雷波相速度(cR)的微震探测技术的空间自相关(SPAC)方法的公式类似。虽然SPAC方法现有的理论确实提供了估计cL的可能性,但这只能通过求解非线性的方程组才能实现,而其中待求解的未知数也包括cR以及瑞雷波?勒夫波的幂分配比。相反,在我们公式中cL是出现的唯一未知数。基于我们推荐公式——我们称为SPAC+L、SPAC-L和CCA-L(其中CCA表示无中心圆形台阵)法——的cL估算法的现场适用范围通过2个测试点的分析结果说明。在所提出的3种技术中,SPAC+L法由于表现最佳而出名。3种方法的有效波长范围下限是台阵半径r的2～5倍区域,上限是10～25r的区域。近年来,提出了类似的仅涉及cL的圆形台阵微震技术,但与它们相比,我们在此给出的方法,不是在数理计算上繁冗更少,就是在数学上更为简单。
These simple and novel formulas are introduced, and the formulas are helpful when using the second component of microseism, the horizontal motion recorded by a circular array, to directly infer the phase velocity of the Love wave (cL). Our formula is similar to the formula for the Spatial Autocorrelation (SPAC) method of microseismic detection, which is generally used to infer the Rayleigh wave phase velocity (cR). Although the existing theory of the SPAC method does provide the possibility of estimating cL, this can only be done by solving nonlinear equations, where the unknowns to be solved also include the cR and the power distribution of the Rayleigh-Wavef ratio. In contrast, cL is the only unknowns that appear in our formulas. The field of application of the cL estimation method based on our recommended formula - we call SPAC + L, SPAC-L and CCA-L (where CCA stands for no center circular array) - passes the analysis of 2 test points Description. Among the three proposed techniques, the SPAC + L method is known for its best performance. The lower limit of the effective wavelength range of the three methods is a region of 2 to 5 times the radius r of the array and an upper limit of 10 to 25 r. In recent years, a similar circular array microseismic technique involving cL has been proposed, but compared with them, the method we give here is not less complicated in mathematical calculation or more mathematically simple.