Spatial analysis of hypocenter to fault relationships for determining fault process zone width in Japan.
- Abilene Christian University, Abilene, TX
Preliminary investigation areas (PIA) for a potential repository of high-level radioactive waste must be evaluated by NUMO with regard to a number of qualifying factors. One of these factors is related to earthquakes and fault activity. This study develops a spatial statistical assessment method that can be applied to the active faults in Japan to perform such screening evaluations. This analysis uses the distribution of seismicity near faults to define the width of the associated process zone. This concept is based on previous observations of aftershock earthquakes clustered near active faults and on the assumption that such seismic activity is indicative of fracturing and associated impacts on bedrock integrity. Preliminary analyses of aggregate data for all of Japan confirmed that the frequency of earthquakes is higher near active faults. Data used in the analysis were obtained from NUMO and consist of three primary sources: (1) active fault attributes compiled in a spreadsheet, (2) earthquake hypocenter data, and (3) active fault locations. Examination of these data revealed several limitations with regard to the ability to associate fault attributes from the spreadsheet to locations of individual fault trace segments. In particular, there was no direct link between attributes of the active faults in the spreadsheet and the active fault locations in the GIS database. In addition, the hypocenter location resolution in the pre-1983 data was less accurate than for later data. These pre-1983 hypocenters were eliminated from further analysis.
- Research Organization:
- Sandia National Laboratories (SNL), Albuquerque, NM, and Livermore, CA (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 876371
- Report Number(s):
- SAND2004-4899; TRN: US0601184
- Country of Publication:
- United States
- Language:
- English
Similar Records
Determination of fault planes at Coalinga, California, by analysis of patterns in aftershock locations
Complex fault interactions in a restraining bend on the San Andreas fault, southern Santa Cruz Mountains, California
Related Subjects
AFTERSHOCKS
DISTRIBUTION
EARTHQUAKES
FRACTURING
GEOGRAPHIC INFORMATION SYSTEMS
HIGH-LEVEL RADIOACTIVE WASTES
HYPOCENTERS
RESOLUTION
SEISMICITY
Radioactive waste disposal.
High level radioactive waste disposal.
Earthquakes
Japan.