| Abstract: | Locations and velocities were calculated for microseisms occurring in samples of rock subjected to triaxial loading and injection of pore fluid. This was accomplished by analyzing arrival times of acoustic emission using an automatic first arrival picker. Apparent velocity anomalies were observed prior to both failure of intact samples and violent slip in samples containing saw cuts. Further analysis revealed that these fluctuations in calculated velocity were not due to changes in the true seismie velocity. Instead, variations in calculated velocity are shown to be related to sampling errors in picking first arrivals. The systematic picking of late first arrivals for small magnitude events was found to be a persistent bias resulting in low calculated velocities. This has encouraged the reexamination of earthquake records to determine how important sampling biases are in contributing to reported velocity anomalies. ?? 1978 Birkha??user Verlag. |
| Genre: | Article |
| ProdID: | 70012541 |
| Citation Author: | Lockner, D. A.; Byerlee, J. D. |
| Citation Contributing Office: | |
| Citation Datum: | |
| Citation Day: | |
| Citation Edition: | |
| Citation Editor: | |
| Citation End Page: | 772 |
| Citation Issue: | 4-5 |
| Citation Keywords: | |
| Citation Language: | English |
| Citation Larger Work Title: | Pure and Applied Geophysics PAGEOPH |
| Citation LatN: | |
| Citation LatS: | |
| Citation LonE: | |
| Citation LonW: | |
| Citation Month: | |
| Citation No Pagination: | |
| Citation Number Of Pages: | 8 |
| Citation Online Only Flag: | |
| Citation Phsyical Description: | |
| Citation Projection: | |
| Citation Public Comments: | |
| Citation Publisher: | |
| Citation Series: | |
| Citation Series Code: | |
| Citation Series Number: | |
| Citation Search Results Text: | Velocity anomalies: An alternative explanation based on data from laboratory experiments; 1978; Article; Journal; Pure and Applied Geophysics PAGEOPH; Lockner, D. A.; Byerlee, J. D. |
| Citation Start Page: | 765 |
| Citation Volume: | 116 |
| Citation Year: | 1978 |
| Type: | citation/reference |
| Text: | Velocity anomalies: An alternative explanation based on data from laboratory experiments; 1978; Article; Journal; Pure and Applied Geophysics PAGEOPH; Lockner, D. A.; Byerlee, J. D. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| URL (DIGITAL OBJECT IDENTIFIER): | http://dx.doi.org/10.1007/BF00876537 |
| Date Other: | Sun, 1 Jan 1978 00:00 -0600 |
| Publisher: | |
