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[1] In order to understand fully the deformational patterns of the Longitudinal Valley fault system, a major structure along the eastern structure of Taiwan, we mapped geomorphic features near the southern end of the Longitudinal Valley, where many well-developed fluvial landforms record deformation along multiple strands of the fault. Our analysis shows that the Longitudinal Valley fault there comprises two major strands. The Luyeh strand, on the west, has predominantly reverse motion. The Peinan strand, on the east, has a significant left-lateral component. Between the two strands, late Quaternary fluvial sediments and surfaces exhibit progressive deformation. The Luyeh strand dies out to the north, where it steps to the east and joins the Peinan strand to become the main strand of the reverse sinistral Longitudinal Valley fault. To the south, the Luyeh strand becomes an E-W striking monocline. This suggests that the reverse motion on the Longitudinal Valley system decreases drastically at that point. The Longitudinal Valley fault system is therefore likely to terminate abruptly there and does not seem to connect to any existing structure further to the south. This abrupt structural change suggests that the development of the Longitudinal Valley suture occurs through discrete structural 'jumps,' rather than by a continuous northward maturation. Citation: Shyu, J. B. H., K. Sieh, Y.-G. Chen, R. Y. Chuang, Y. Wang, and L.-H. Chung (2008), Geomorphology of the southemmost Longitudinal Valley fault: Implications for evolution of the active suture of eastern Taiwan. Tectonics, 27, TC1019, doi:10.1029/ 2006TC002060.

Numerous landforms along the Longitudinal Valley suture of eastern Taiwan indicate that two opposing reverse faults currently dominate the suturing process between the Luzon volcanic arc and the Central Range of Taiwan. The east-dipping Longitudinal Valley fault, on the eastern flank of the valley, is well known. The west-dipping Central Range reverse fault, on the western flank of the valley, is more obscure. Nonetheless, it has produced many uplifted lateritic fluvial terraces along the eastern flank of the Central Range in the central reach of the valley, from just north of the Wuhe Tableland to near Chihshang. The fault appears to be active but blind south of Chihshang and inactive along the northern part of the Longitudinal Valley. The late Quaternary slip rate of the fault is less than 12.8 mm/yr. This constraint means that the fault is absorbing far less than half of the horizontal shortening across the Longitudinal Valley suture. However, the late Quaternary slip rate along the fault may be comparable to the uplift and exhumation rate of the Central Range. This suggests that localized brittle slip along the Central Range fault is an important component of crustal thickening and uplift of the range, even though additional shortening and crustal thickening may be occurring because of pervasive deformation beneath the range. Keywords: Taiwan, tectonic geomorphology, Central Range fault, Longitudinal Valley, sutures, exhumation.

We document the precise sizes, but not the dates, of the six latest offsets across the San Andreas fault at Wallace Creek, California. Three and perhaps four of these, including the latest in 1857, show dextral offset of 7.5-8 m. The third and fourth offsets, however, are just 1.4 and 5.2 m. The predominance of similar offsets for the latest six events suggests that the fundamental properties of the fault system that control slip size do not vary greatly from event to event. The large offsets imply that ruptures involving this site are typically more than 200 km long. Keywords: San Andreas, fault, paleoseismology, earthquake, rupture.

A study was conducted on the uplift and erosion of the San Bernardino Mountains (SBMs) in southern California. The low-temperature cooling history of the SBMs was analyzed using radiogenic helium thermochronometry. Results showed that the helium ages of the uplift predate the present uplift of the range and that exhumation was only several kilometers since the Late Cretaceous. These results suggest that the uplift and exhumation is associated with transpression along the San Andreas fault.

Data from geotechnical boreholes and trenches, in combination with geomorphologic mapping, indicate that the Hollywood fault is an oblique, reverse-left-lateral fault that has undergone at least one surface-rupturing earthquake during latest Pleistocene to middle or late Holocene time. Geomorphologic observations show that the fault extends for 14 km along the southern edge of the eastern Santa Monica Mountains, from the Los Angeles River westward through downtown Hollywood to northwestern Beverly Hills, where the locus of active deformation steps 1.2 km southward along the West Beverly Hills lineament to the Santa Monica fault. Rupture of the entire Hollywood fault, by itself, could produce a [M.sub.w] [approximately]6.6 earthquake, similar in size to the highly destructive, 1994 Northridge earthquake, but even closer to more densely urbanized areas. Assuming a 0.35 mm/yr minimum fault-slip rate consistent with available geologic data, we calculate an average maximum recurrence interval for such moderate events of [less than or equal to][approximately]4000 yr. Although occurrence of such moderate events is consistent with the elapsed time since the poorly constrained age of the most recent surface rupture, the data do not preclude a longer quiescent interval suggestive of larger earthquakes. If earthquakes much larger than [M.sub.w] [approximately]6.6 occurred in the past, we speculate that they may have been generated by the Hollywood fault together with other faults in the Transverse Ranges Southern Boundary fault system.

The Wilshire fault is a potentially seismogenic, blind thrust fault interred to underline and cause the Wilshire arch, a Quaternary fold in the Hollywood area, just west of downtown Los Angeles, California. Two inverse models, based on the Wilshire arch, allow us to estimate the location and slip rate of the Wilshire fault, which may be illuminated by a zone of microearthquakes. A fault-bend fold model indicates a reverse-slip rate of 1.5-1.9 mm/yr, whereas a three-dimensional elastic-dislocation model indicates a right-reverse slip rate of 2.6-3.2 mm/yr. The Wilshire fault is a previously unrecognized seismic hazard directly beneath Hollywood and Beverly Hills, distinct from the faults under the nearby Santa Monica Mountains.

This study presents a distinctive type of Muslim gravestone found on the northern coast of Sumatra, Indonesia, that dates to the 15th century. These grave markers, locally known as plang-pleng, provide evidence for the formation and disappearance of an early form of vernacular Muslim material culture in Southeast Asia. We documented over 200 of these gravestones during a large-scale archaeological landscape survey. In this article, we present a typology of these gravestones based upon shape, morphology and ornamentation. We then discuss their geographical distribution and periodisation based on examples with dated Arabic inscriptions. Our results show that these gravestones were initially a cultural product of the historic trading settlement of Lamri dating from the early 15th century. By the middle of the 15th century, variations of these stones started to appear widely near the Aceh river. The plang-pleng tradition was displaced in the early 16th century by the batu Aceh gravestones associated with the Aceh sultanate, which became a standardised part of Muslim material culture in the region for the next two centuries. [ABSTRACT FROM AUTHOR]