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The 1989 Mw 6.9 Loma Prieta earthquake is the first major event to occur along the San Andreas fault (SAF) zone in central California since the 1906 M 7.9 San Francisco earthquake. Given the complexity of this event, uncertainty has persisted as to whether this earthquake ruptured the SAF itself or a secondary fault. Recent work on the SAF in the Coachella Valley in southern California has revealed similar complexity, arising from a nonplanar, nonvertical fault geometry, and has led us to reexamine the Loma Prieta event. We have compiled data sets and data analyses in the vicinity of the Loma Prieta earthquake, including the 3D seismic velocity model and aftershock relocations of Lin and Thurber (2012), potential field data collected by the U.S. Geological Survey following the earthquake, and seismic refraction and reflection data from the 1991 profile of Catchings et al. (2004). The velocity model and aftershock relocations of Lin and Thurber (2012) reveal a geometry for the SAF that appears similar to that in the Coachella Valley (although rotated 180°): at Loma Prieta the fault dips steeply near the surface and curves with depth to join the moderately southwest-dipping main rupture below 6 km depth, itself also nonplanar. The SAF is a clear velocity boundary, with higher velocities on the northeast, attributable to Mesozoic accretionary and other rocks, and lower velocities on the southwest, attributable to Cenozoic sedimentary and volcanic rocks of the La Honda block. Rocks of the La Honda block have been offset right-laterally hundreds of kilometers from similar rocks in the southern San Joaquin Valley and vicinity, providing evidence that the curved northeast fault boundary of this block is the plate boundary. Thus, we interpret that the Loma Prieta earthquake occurred on the SAF and not on a secondary fault.

This study assessed the potential for a high-temperature blind geothermal system in southeastern Gabbs Valley, an area with no previous geothermal exploration, by utilizing geothermal play fairway analysis. Gabbs Valley is a structurally complex, tectonically active basin occupying a transtensional displacement transfer zone. Multiple lines of evidence suggest the presence of a blind geothermal system, including collocated intersecting gravity gradients, magnetic-low, low-resistivity, 2-m temperature anomaly, and 130–140 °C geothermometers obtained from nearby agricultural wells. Six 150 m-deep temperature-gradient holes were drilled to target the geophysical and thermal anomalies. Two holes produced bottom-hole temperatures of 114.5 °C and 124.9 °C. Drilling results establish the discovery of a blind geothermal system. Power estimates based on resource conceptual models of the geothermal system suggest a median (P50) capacity of ∼16 MWe.

The Clear Lake Volcanic Field in northern California is the youngest and northern-most part of a long-lived volcanic system that has produced recent (~10 ka) eruptions. Adjacent to the Clear Lake Volcanic Field is the world's largest energy producing geothermal field, The Geysers. The hottest part of The Geyser's geothermal field is in the northwest where temperatures reach ~400 °C at 3 km depth. Low permeability, high thermal gradients, and low steam saturation prescribed development of an enhanced geothermal system (EGS) in the Northwest Geysers to increase energy producing capacity. Though the Northwest Geysers is known to be the hottest part of the field, geophysical methods have failed to adequately image any inferred heat source. This project aims to image the heat source of the Northwest Geysers using newly collected gravity and magnetotelluric (MT) measurements. Gravity data were jointly modeled with existing magnetic data along a two-dimensional profile aligned with an existing geologic cross-section. The key feature of the potential field model is a low-density, low-susceptibility body at 5 km depth (bmsl) under the EGS. MT data were modeled in three-dimensions to characterize subsurface resistivity structure, where the upper 3 km of the resistivity model agrees well with existing data. Lithologic and steam saturation are estimated from modeled resistivity values using existing geophysical data. Below 3 km depth (bmsl), the resistivity model images a possible young intrusion under the EGS. A possible zone of partial melt (

With unemployment having now passed the critical 3 million level there is intense pressure on the Chancellor to adopt a more reflationary stance in the coming Budget. Even within the confines of the present strategy there appears to be some scope for a limited expansion. This review of UK and world economic data will appraise recent economic performance and make predictions about future economic prospects.

The outlook for the Scottish, and indeed British, economy is not encouraging. The figures of industrial output for June record a fall of 1.5%, suggesting that the nascent recovery in output experienced earlier this year is in need of intense incubation. Both domestically and internationally there appears to be little sign of policies designed to assist any such incubation.

Throughout this year economists, industrialists and politicians have been analysing and discussing the economy and making countervailing claims as to whether or not the recession is over. While many industrialists are clearly aware of the factors influencing their own business they are uncertain of the economy wide prospects. Meanwhile politicians couch their economic analysis in language which maximises their own political objectives. Similarly many economists attempt to defend the schools of thought upon which their reputations are staked. The conflicting viewpoints expressed have resulted in widespread confusion about the future prospects of both the Scottish and British economies. However, much of this confusion arises out of a failure to differentiate between the effect the current recession has had on the level of output and on the level of unemployment. It is widely recognised that a strong relationship exists between these variables and that changes in the level of unemployment lag behind changes in the level of output. It is worthwhile examining each of these factors and assessing their likely future movements.

While the world economy has slowed down dramatically, the UK economy seems becalmed. Although industrial production fell in July at least GDP is not declining as it did during 1980 and 1981. However as yet there are no strong indications of a revival in economic activity.

The data analysed in this paper will show that whilst the end of the recession may be approaching, there is no strong evidence of any sustained or substantial recovery. Indeed, as highlighted in the UK section, there is no clear evidence that the mechanisms upon which the government are relying will generate a significant upturn. The UK economy is notoriously unresponsive to price signals, and while one should support governments efforts to increase this sensitivity, historical evidence is at best equivocal on the efficacy of this approach. For example, while the response of manufacturing investment to changes in output is unambiguously positive, the response to changes in the cost of capital is unclear. Indeed the Treasury have been unable to establish a significant relationship between manufacturing investment and capital cost and, in consequence, base their forecasts on the assumption that such a link exists. Further, any positive effects which might stem from a fall in interest rates will be dampened by the considerable spare capacity in the manufacturing sector brought about by the depth of the current recession.

The textiles, leather, clothing and footwear sector (TLCF) encompasses a wide variety of industries producing a heterogeneous collection of products. It is not within the scope of this brief to analyse in detail such a complex mix of industries. Therefore the purpose of this brief is to describe the performance of the sector as a whole, within the context of the Scottish economy and to discuss the observed trends in the main economic variables outlined below. It should be noted that a study of the data available for the TLCF sector reveals numerous inconsistencies and deficiencies.