The scalar moment and moment magnitude of microseismic events

Autor: Bradley Bankhead, Arcangelo Sena, Wenjie Jiao, Michael Davidson
Rok vydání: 2013
Předmět:
Zdroj: SEG Technical Program Expanded Abstracts 2013.
DOI: 10.1190/segam2013-1370.1
Popis: Summary We investigate the seismic moment and moment magnitude for microseismic events. We show that the scalar moment M T 0 defined by Bowers and Hudson (1999) should be used in microseismic studies for characterizing the size of an event and calculating its moment magnitude. For nondouble couple sources, the so called “Brune model” is no longer an appropriate way for estimating the seismic moment and magnitude. Moreover, the S wave alone is not sufficient for determining the total seismic moment. Instead, P wave must be studied in order to determine the total seismic moment of an event. An example Barnett Shale dataset is studied and the results show that the magnitudes estimated through Brune model are off by as high as 1.92, with an absolute average of 0.35. The moment magnitudes based on the scalar moment M T 0 also give a more reasonable size distribution and b-value estimation.
Databáze: OpenAIRE