渭河盆地边界活动断裂的分形几何特征

本文运用分形几何理论,对渭河盆地两条边界活动断层即秦岭北缘活断层和北山南缘活断层进行了分维度量,发现活断层的维数大小反映了断裂活动性的强弱程度,高维数对应着构造活动性强和地震活动丛集的断层段,而低维数则刚好相反。

FRACTILE GEOMETRIC FEATURES OF THE TWO MARGIN ACTIVE FAULTS IN THE WEIHE BASIN

The fractile dimensions of the north margin faults of the Qinling mountains and the north margin faults in the weihe Basin are calculated by means of fractile geometry. The tatal fractile dimensions of the first fault are 1. 28 (D=l. 28). The difference between the whole fractile dimension and the partial one is apparent . that is, part A : D=l. 233; part B : D = l. 302; part C : D=l. 351. The total fractile dimension of the last fault is 1. 384(D = 1. 384); the partial fractile dimensions are given: part A : D=l. 317; part B : D=l. 392; part C : D=l. 455. The research indicated that different geometric structures and active intensity are displayed by partial fractile dimension of the active fault. The high fractile dimension is corresponded with the high rate of the branch faults and the complicated geometric structure region and vice versa. Regions which have high fractile dimensions are also charac-terissed by the high rate of earthquakes.