Active Deformation of Northern L.A. Region
Active Deformation of the Northern Los Angeles Region -- What Earth Scientists Know and Need to Know
Dates: Thursday, October 27 and Friday, October 28
Organizers: Gary Fuis, Lucy Jones, and Rufus Catchings
Location: Caltech, South Mudd Building, Salvatori Room (3rd floor)
In the Fall of 2005, the U.S. Geological Survey (USGS) and Southern California Earthquake Center (SCEC) held a workshop entitled "Active Deformation of the Northern Los Angeles Region." The chief purposes of this workshop were (1) to understand on which faults strain is currently building up and (2) to understand the history of strain build-up and release (earthquakes) backward through time. Recent geodetic studies have indicated that a zone between downtown Los Angeles (LA) and the San Gabriel Mountains is contracting at a rate that would, if concentrated on a single thrust fault, produce one or more M 6.5-7.0 earthquakes every ~100 years, or larger quakes more infrequently. This deformation may be concentrating on blind thrust faults just north of and(or) beneath downtown LA, but more modeling of the deformation is required to confirm this result. Recent subsurface-imaging studies, studies of landforms (hills, valleys), and studies of trenches across faults have shown a major zone of past deformation and past earthquakes extending from the region of the Puente Hills to the region of downtown LA. The 1987 M 5.9 Whittier Narrows earthquake occurred in the eastern part of this zone.
The workshop lasted 2 days, with the first day, Thursday Oct. 27, devoted to scientific talks and discussion of the northern Los Angeles region and the second day, Friday Oct. 28, devoted to a discussion of the results of the first day with cities in this region and other government agencies. You can now view the presentations and the text of talks for Day 2 by clicking on links in the agenda below.
Friday, October 28
08:00 | Coffee and donuts | |
08:30 | Arrival and Welcome | |
08:45 | 1. Overview of Earthquake Hazard in the northern Los Angeles Basin and San Gabriel Valley | Jones |
2. Available Earthquake Products and Services | Hauksson | |
3. Unique Geologic Problems of the northern Los Angeles Basin and the San Gabriel Valley | Fuis | |
Coffee break | ||
4. Unique Geologic Problems of the northern Los Angeles Basin and the San Gabriel Valley | Fuis | |
5. What Do Scientists Need to Solve these Problems? |
Hudnut Jordan |
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6. What Do Cities Need?
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Jones, Fuis | |
11:15 | Lunch (provided) | |
12:15 | 7. Discussion and Conclusions | |
13:30 | Adjourn |