The San Andreas Fault (SAF) is the primary structure within a system of faults accommodating motion between the North American and Pacific plates. Physical models of faulting and characterizations of seismic hazard are informed by investigations of paleoseismology, slip distribution, and slip rate. The impact of earthquakes on people is…
The San Andreas Fault (SAF) is the primary structure within a system of faults accommodating motion between the North American and Pacific plates. Physical models of faulting and characterizations of seismic hazard are informed by investigations of paleoseismology, slip distribution, and slip rate. The impact of earthquakes on people is due in large part to social vulnerability. This dissertation contributes an analysis about the relationships between earthquake hazard and social vulnerability in Los Angeles, CA and investigations of paleoseismology and fault scarp array complexity on the central SAF. Analysis of fault scarp array geometry and morphology using 0.5 m digital elevation models along 122 km of the central SAF reveals significant variation in the complexity of SAF structure. Scarp trace complexity is measured by scarp separation, changes in strike, fault trace gaps, and scarp length per SAF kilometer. Geometrical complexity in fault scarp arrays indicates that the central SAF can be grouped into seven segments. Segment boundaries are controlled by interactions with subsidiary faults. Investigation of an offset channel at Parkfield, CA yields a late Holocene slip rate of 26.2 +6.4/- 4.3 mm/yr. This rate is lower than geologic measurements on the Carrizo section of the SAF and rates implied by far-field geodesy. However, it is consistent with historical observations of slip at Parkfield. Paleoseismology at Parkfield indicates that large earthquakes are absent from the stratigraphic record for at least a millennia. Together these observations imply that the amount of plate boundary slip accommodated by the main SAF varies along strike. Contrary to most environmental justice analyses showing that vulnerable populations are spatially-tied to environmental hazards, geospatial analyses relating social vulnerability and earthquake hazard in southern California show that these groups are not disproportionately exposed to the areas of greatest hazard. Instead, park and green space is linked to earthquake hazard through fault zone regulation. In Los Angeles, a parks poor city, the distribution of social vulnerability is strongly tied to a lack of park space. Thus, people with access to financial and political resources strive to live in neighborhoods with parks, even in the face of forewarned risk.
Successful public transit systems increase the value of locations they serve. Capturing this location value to help fund transit is often sensible, but challenging. This article defines location value capture, and synthesizes lessons learned from six European and North American transit agencies that have experience with location value capture funding.…
Successful public transit systems increase the value of locations they serve. Capturing this location value to help fund transit is often sensible, but challenging. This article defines location value capture, and synthesizes lessons learned from six European and North American transit agencies that have experience with location value capture funding. The opportunities for and barriers to implementing location value capture fall into three categories: agency institutional authority, agency organizational mission, and public support for transit. When any of these factors is incompatible with a location value capture strategy, implementation becomes difficult. In four of the cases studied, dramatic institutional change was critical for success. In five cases, acute crisis was a catalyst for institutional change, value capture implementation, or both. Using value capture strategies to fund transit requires practitioners to both understand agency organizational constraints, and to view transit agencies as institutions that can transform in response to changing situations.
