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Uphill-facing scarps develop in the central Swiss Alps, particularly along the Upper Rhone valley, the Urseren valley, the Upper Rhine valley, and Bedretto valley. It has been argued whether they have gravitational origin, tectonic origin, or differential uplift after the deglaciation. We made geological survey and topographic interpretation in the Bedretto valley, in which the Ticino River flows from the west-southwest to east-northeast. The Bedretto valley slopes have shoulders on both sides of the valley at elevations of 1500 to 1900 m, below which is a lower U-shaped valley. Uphill-facing scarps develop more on the southern side slopes of the Bedretto valley, where is underlain mainly by mica schist of the Bedretto zone, than on the northern side slopes, where is underlain mainly by gneiss and slate. In addition, they develop much more on slopes higher than the slope shoulders, and the uphill-facing scarps on the lower U-shaped valley are much smaller in scale. Tributary valleys on the south side of the Bedretto valley go down into this lower U-shaped valley from the southeast with intervening ridges, and we surveyed along the valleys of Ri di Cristallina, Ri di Valleggio, and Val Cavagnolo. We found that steeply-dipping schistosity in the ridges is toppled valleyward with brittle fractures along the hinge zones, which are approximately along or slightly higher than the tributary valley bottom. Rock mass as thick as 300 m thus toppled. Flexural toppling of mica schist developed uphill-facing scarps, which were mostly along high-angle faults, some of which were recognized to have brittle crush zones. The flexural toppling generated extension field in the upper ridges, where rock mass apparently settled down along normal faults. The reason why the northern side slopes of the Bedretto valley have much smaller uphill facing scarps may be due to the rocks are mainly gneiss and also due to the numbers of faults are possibly much less than in the southern slopes . The facts that uphill facing scarps are mainly developed above the lower U-shaped valleys may be related to the longer time intervals of the exposure of slopes higher than the slope breaks to the atmosphere during the glacial age.

Individuals with knee osteoarthritis (OA) show various dynamic sagittal-plane changes during the early stance phase of gait. However, the effect of these kinematic alterations on knee load during the early stance remains poorly understood.The purpose of this study was to examine the effect of altered sagittal- plane knee kinematics on knee load during the early stance.A total of 13 healthy adult men underwent gait analysis trials using four conditions (baseline and three altered conditions). The three altered conditions were defined as follows: 1) Less flexion (LF): a gait that decreased knee flexion excursion (KFE) owing to a reduced peak knee flexion angle compared to baseline. 2) Initial flexion (IF): a gait with decreased KFE owing to an increased knee flexion angle at initial contact, during which the peak knee flexion angle did not differ from baseline. 3) Flexion gait (FG): a gait that increased the knee flexion angle at initial contact but did not reduce KFE compared with the baseline. Data analyzed included peak external knee flexion moment (KFM), KFM impulse (impulse was an integral value from initial contact to peak value), peak vertical ground reaction force (VGRF), and maximum loading rate.Both LF and IF conditions significantly decreased peak VGRF (p 0.05) compared with the baseline. Peak KFM decreased in the LF condition and increased in the FG condition versus baseline (p 0.05). A significantly increased KFM impulse was found in both IF and FG conditions when compared with baseline (p 0.05).An increase in knee flexion angle during early stance increased knee loading. Interventions are likely required for improving excessive knee flexion during early stance phase of gait in individuals with knee OA.

Earthquakes are considered to be important triggers of deep-seated gravitational slope deformation (DGSD) in seismically active regions, and if that is the case, DGSD features could be candidates for off-fault paleoseismology investigations. On the basis of pit excavations and sediment cores at an off-fault DGSD site and a trench excavation across the active Neodani fault at a nearby site, we examined the records of DGSD and surface-rupturing paleoearthquakes of the Neodani fault. The four most recent DGSD events were dated at after 240 cal BP, 1710–340 cal BP, 4730–3970 cal BP, and 5570–5340 cal BP. The four most recent surface-rupturing earthquakes were dated at 1891 CE (the Nobi earthquake), 2010–1220 cal BP, 7180–2110 cal BP, and before 9540 cal BP. We conclude that the ages of the four DGSD events are consistent with surface-rupturing earthquakes on the adjacent Neodani fault. We infer that static crustal strain from repeated seismogenic faulting plays an important role in the occurrence of DGSD events, at least in the immediate vicinity of active faults, although coseismic severe shaking would have at least some effect on them. Our case study suggests that off-fault DGSDs can be used to reconstruct or refine the paleoseismic history of a nearby active fault. We propose that an ideal DGSD for that purpose would be located in an area of concentrated strain near a termination, bend, or stepover of the target fault.

We present a new approach for recognizing the origin of accreted basaltic rocks based on ocean plate stratigraphy (OPS), and on the petrology and geochemistry of basalts from mid-oceanic ridges (MORB) and oceanic islands (OIB) using examples from four accretionary complexes (AC) in SW Japan: Akiyoshi, Mino–Tamba, Chichibu and Shimanto. The key to the problem is the model of OPS, which includes an association of igneous and sedimentary rocks that form on an oceanic plate during its travel from a mid-oceanic ridge to a subduction zone. We propose the reconstruction of the tectonic settings of basalts according to their relationships with associated OPS sediments, their petrogenesis and their geochemical features. Five types of OPS are recognized in the accretionary complexes of SW Japan: (1) sandstone/shale; (2) sandstone/shale and chert; (3) sandstone/shale, chert and MORB; (4) sandstone/shale, chert, MORB and gabbro (± peridotite); (5) seamount OPS including OIB, cap carbonates, slope clastics and basal shale/chert. The alkaline, tholeiitic or calc-alkaline composition of basaltic melts, which are typical of oceanic islands, mid-oceanic ridges and island-arcs, respectively, can be identified by the sequence in crystallization of their major phenocrysts, i.e. olivine (ol), clinopyroxene (cpx) and plagioclase (pl), and by their compositions. Alkaline and calc-alkaline mafic lavas are characterized by an ol → cpx → pl succession, whereas tholeiitic melts by their ol → pl ± cpx succession. Titanium-rich minerals, e.g., Ti–augite, kaersutite, Ti–biotite, are typical of alkaline lavas. The application of geochemistry-based tectonic discrimination diagrams is also a powerful tool, if not supported by geological and petrological data, may result in confusion due to magma contamination, post-magmatic alteration, and secular change of mantle thermal conditions. We propose that a direct comparison of normalized multi-element patterns and key binary plots from older volcanic rocks with their modern analogues provides a more viable and reliable method of basalt discrimination. Our OPS–petrology–geochemistry method allows us to confirm the above conclusions that the lavas of the Akiyoshi, Mino–Tamba and Southern Chichibu AC formed in oceanic islands, because they are associated with seamount OPS sediments, crystallized from ol to cpx and pl, contain Ti–augite and kaersutite and are enriched in TiO2, LREE and Nb. In this paper we present geochemical data from the Inuyama basalts of the Mino–Tamba AC and from the Toba complex in the huge Mikabu greenstone belt of the Chichibu AC. The Inuyama basalts are in contact with Jurassic pelagic cherts, but their geochemical features are confusing; they contain phenocrysts of ol, Ti–augite and kaersutite and therefore probably formed in seamounts. The Toba volcanic rocks are a part of the huge ophiolite belt; they have flat to slightly LREE-enriched REE patterns, are characterized by an ol → cpx succession of phenocrysts and they plot in the OIB field in binary plots suggesting they formed in an oceanic plateau.

In managed forests, partial harvest within riparian areas is one way to provide harvest opportunities and maintain some of the functions of riparian vegetation. We examined the response of coniferous seedlings to a 50 %-partial harvest in a second-growth, coniferous riparian forest in the Pacific Northwest. Partial canopy opening facilitated the establishment of Tsuga heterophylla and Thuja plicata, but Pseudotsuga menziesii did not show the same tendency. Results suggested that differences in seedling establishment were related to differences in light. Increased light availability also stimulated growth of Rubus spectabilis, especially in moist sites, and the dense cover precluded establishment of coniferous seedlings. Once R. spectabilis was established, continued stem recruitment maintained a dense stable cover, and even intense disturbance did not affect the stability of the populations. R. spectabilis would be a major competitor to constrain conifer seedlings to regenerate in riparian zones. Although Gaultheria shallon extended their cover, competition from dense G. shallon was not as severe as from R. spectabilis.

The relationship between large deep-seated landslides and geologic structures characteristic of accretionary complexes were examined in the Chichibu belt on the eastern part of the Kii Peninsula, central Japan. In the Chichibu belt, bedrock consists of Jurassic accretionary complexes composed of basalt, limestone, chert, Permian–Triassic boundary siliceous shale (PTBS), mudstone, sandstone, and melanges with sheared shale matrices. The landslides treated in this paper include prehistoric examples involving volumes greater than one million cubic meters (located in the Karako, Sono, Kasagi, and Aso areas), and the modern Kasugadani landslide that was triggered by the Typhoon Meari on 29–30 September 2004. The age of the landslide in the Sono area was estimated at 20,440 ± 70 BP and 20,820 ± 70 BP based on AMS-14C ages of wood fragments embedded in the dammed lake sediments, while ages of the other prehistoric slides are not known. All of the landslides occurred on dip slopes. The bedding, foliation, and fault planes of the rocks in the area generally trend E–W and dip to the north, although those in the Kasugadani area dip to the south as a result of local folding. The landslides selectively slid along the planes of (1) PTBS horizons that were less strong than those of underlying chert, (2) lithologic boundaries with physical contrasts, or (3) boundary faults between melange units. These geologic structures, including the north-dipping bedding/cleavage/fault planes, were formed during Jurassic subduction–accretion and later uplift processes. The movement directions estimated for the 269 landslides and unstable slopes in this region are also N–NNE, and their slip planes are subparallel to the general bedding/cleavage planes in this area. Thus, future slides are also likely to occur on north-facing slopes.