9416760 Johnson This study will determine whether areas of concentrated damage to houses, roads and other structures can be ascribed to areas of localized ground deformation along buried faults during the January 17, 1994 Northridge earthquake. Preliminary investigations have identified zones of fracturing in the vicinity of Tampa Avenue and Balboa Avenue. Details of ground deformation will be assessed with pre- and post-earthquake ground surveys and aerial photographs. measurements of changes in length of lines between manhole covers, fire hydrants, etc. will be used to prepare a detailed, two-dimensional strain grid map. The results will indicate whether the localized damage in the stud areas after the Northridge event was due primarily to ground deformation, or to some other mechanism such as shaking in valley fill, and will thus help in evaluating the seisin hazard of other areas of the Los Angeles basin that contain buried faults.
