A Preliminary Study on the Motion Characteristics of Longmenshan Fault Before and After the M8.0 Wenchuan Earthquake

Abstract eng:
This paper utilizes the mobile short-line leveling data from various observation sites across the Longmenshan fault to analyze the variation characteristics before and after the Wenchuan earthquake. By analyzing the motion type and stress pattern of the Longmenshan fault we investigate the seismogenic process and mechanism of the earthquake. The preliminary result is as follows. a) Before the Wenchuan earthquake the cross-fault short-line leveling measurements showed the activity of Longmenshan fault around 2006, and they all showed a characteristic of accelerated movement to different degrees before the earthquake. b) Before the earthquake the short-line leveling measurements across different faults indicated that the middle-south segment of Longmenshan fault showed reverse faulting movement, and the fault deformation was of backward “S” type. c) Before and after the Wenchuan earthquake the cross-fault displacement measurements reflected the spatial-temporal evolution of the accumulation and release of regional ground-surface stress, the interpretation of their mechanism is basically consistent with the focal mechanism solution.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket