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While there has been significant research on the dating of paleoearthquakes using methods such as surface cosmogenic dating, and trench-based luminescence or radiocarbon dating, this paper focuses on implementing an alternative surface dating method using a fault scarp-based optically stimulated luminescence (OSL) dating approach. Hence for the first time, we investigated the Pleistocene to Holocene earthquake cycle of the Manisa Fault, one of the dip-slip active faults of the Western Anatolia extensional province, utilizing novel OSL surface exposure techniques. In this technique, OSL bleaching profiles on the fault surface are directly related to the exposure of the fresh fault scarps that are produced by earthquakes. The results indicate that the Manisa Fault is responsible for at least six surface rupturing earthquakes since the Holocene, occurring at 154 ± 22 year (E6: LSD3), 416 ± 48 year (E5: LSD4), 1103 ± 82 year (E4: LSD5), 2067 ± 138 year (E3: LSD6), 5376 ± 48 year (E2: LSD7), and 6432 ± 218 year (E1: LSD8). Our results of the first use of this novel method on the Manisa Fault are in agreement with prior cosmogenic dating of fault scarps and trench-based paleoseismological chronological data, and we conclude that the OSL surface chronology is a promising alternative for fault scarp dating of paleoearthquakes. [ABSTRACT FROM AUTHOR]

Glacial successions in the Anyemaqen and Nianbaoyeze Mountains of northeastern Tibet are reassessed and new glacial chronologies are presented for these regions. Cosmogenic radionuclide and optically stimulated luminescence dating indicates that two glacial advances occurred in marine isotope stage (MIS)-3 and MIS-2. In the Anyemaqen Mountains, a third advance occurred in the Early Holocene. We suggest that glaciation was synchronous in the Anyemaqen and Nianbaoyeze Mountains, as well as in other glaciated areas of Tibet and the Himalaya that are influenced by the Asian monsoon. The maximum extent of glaciation occurred early in the last glacial cycle (MIS-3) during a time of increased insolation when the monsoon intensified and supplied abundant precipitation, as snow at high altitude, to feed high-altitude glaciers. This suggests that precipitation, as snow, is fundamental in controlling glaciation in these regions. However, the occurrence of glacial advances during the insolation minimum of MIS-2 suggests that, despite reduced precipitation at this time, the annual temperatures were cold enough to maintain positive glacier mass balances. The numerically defined chronologies for the Anyemaqen and Nianbaoyeze Mountains presented here provide a framework for comparing glacial advances in other parts of high Asia. Keywords: Tibet, glaciation, monsoon, cosmogenic radionuclide dating, optically stimulated luminescence dating.

Moraines south of Mount Everest in the Khumbu Himal were dated using optically stimulated luminescence. Clustering of ages and morphostratigraphy allowed three advances to be dated: (1) the Periche Glacial Stage (ca. 18-25 ka), (2) the Chhukung Glacial Stage (ca. 10 ka), and (3) the Lobuche Stage (ca. 1-2 ka). The Periche Stage is coincident with Oxygen Isotope Stage 2; the Chhukung Stage represents a late glacial or early Holocene glacial advance; and the Lobuche Stage is a late Holocene glacial advance that predates the Little Ice Age. Keywords: dating, glaciers, Himalaya, Last Glacial Maximum, monsoons, Mount Everest.

Holocene aeolian sand sheets at the margins of high-level deflation surfaces in the Scottish Highlands commonly comprise two units: a lower weathered unit representing slow accumulation throughout much or all of the Holocene, and an upper unit of structureless sand that is inferred to represent recent erosion of aeolian deposits and aeolisols from adjacent plateaux. OSL dating of samples from above and below the upper-lower unit contact at three sites in NW Scotland places the onset of upper unit sediment accumulation within the interval AD 1550–1700. Accumulation rates calculated from OSL ages confirm rapid accumulation of upper-unit deposits. The timing of the onset of upper-unit sand accumulation excludes expansion of sheep grazing, intrinsic instability and atmospheric pollution as triggers of plateausurface vegetation degradation and consequent erosion, but favours climatic deterioration (increased wind stress and possibly prolonged snow-lie) during the —Little Ice Age― as the likely cause. This explanation does not, however, apply in all cases; at an OSL-dated site in the Grampian Highlands upper-unit aeolian sand accumulation commenced around AD 1900. [ABSTRACT FROM AUTHOR]

In this study we have investigated the apparent dose (De*) distribution in four samples of young sedimentary quartz from different depositional environments, and on standard quartz comprised of artificial binary-dose mixtures. We have used a simplified two-step single-aliquot regenerative-dose (SAR) approach to rapidly measure De* from a large number of small aliquots (∼50–100 grains), with a small sub-set subjected to routine SAR measurements to enable monitoring of luminescence characteristics. We have used an F-ratio analysis to interpret De* distributions. This analysis is sensitive to structure, the leading edge and modal data in De* distributions, indicated by inflections and plateaux in F-ratio plots. We cautiously suggest that F-ratios at or approaching unity may indicate a single dose component. [Copyright &y& Elsevier]

Uplifted marine terraces are common landforms in coastal regions where active tectonics are an important component of landscape evolution, such as along the coastal stretches of southern California. The pattern and elevation of shoreline angles on active folds provide information about rates of uplift and fold growth, which is important for defining tectonic models. A particularly impressive succession of marine terraces are developed across the Santa Barbara fold belt (SBFB) in southern California, which comprises an east-west linear zone of active folds and (mostly) blind faults on the coastal piedmont and in the Santa Barbara Channel. The fold belt is characterized by several flights of emergent late Pleistocene marine terraces uplifted and preserved on the flanks of active anticlines. At several locations along the fold belt, the first emergent marine terrace is numerically dated by methods that include uranium-series dating on terrace corals, 14C dating on terrace shells and detrital charcoal, optically stimulated luminescence of marine terrace sands, and oxygen isotopic signatures (δ18O) of mollusks. Individual marine terraces have as many as four ages, using up to three different dating methods, providing confidence in terrace chronology. Ages of higher terraces are estimated assuming a constant rate of uplift for a particular flight. Of the 31 terraces, 22 formed during a time of falling sea level, with 9 forming at or near marine oxygen isotope stage (MIS) 3 or 5 highstands. Ages and rates of uplift of the first emergent terrace vary systematically from west (younger and higher) to east (older and lower). The first emergent marine terraces in the western-most SBFB are approximately 45 ka (MIS 3), and the rate of local surface uplift is ~2 m/k.y. In the central part of the belt, ? rst emergent terraces date to 60-70 ka (MIS 5), and uplift rates decrease to ~1.2 m/k.y. First emergent marine terraces preserved in the easternmost fold belt range from 70 ka to 105 ka (MIS 5), with rates of local surface uplift of ~0.5 m/k.y. Lower rates of uplift in the eastern end of the fold belt result from the MIS 5 terrace being tilted down into the Carpinteria syncline. Rates of vertical uplift in the western end of the fold belt are about six times higher than previously reported, suggesting the seismic hazard is also greater. [ABSTRACT FROM AUTHOR]

Glacial successions in the Anyemaqen and Nianbaoyeze Mountains of northeastern Tibet are reassessed and new glacial chronologies are presented for these regions. Cosmogenic radionuclide and optically stimulated luminescence dating indicates that two glacial advances occurred in marine isotope stage (MIS)-3 and MIS-2. In the Anyemaqen Mountains, a third advance occurred in the Early Holocene. We suggest that glaciation was synchronous in the Anyemaqen and Nianbaoyeze Mountains, as well as in other glaciated areas of Tibet and the Himalaya that are influenced by the Asian monsoon. The maximum extent of glaciation occurred early in the last glacial cycle (MIS-3) during a time of increased insolation when the monsoon intensified and supplied abundant precipitation, as snow at high altitude, to feed high-altitude glaciers. This suggests that precipitation, as snow, is fundamental in controlling glaciation in these regions. However, the occurrence of glacial advances during the insolation minimum of MIS-2 suggests that, despite reduced precipitation at this time, the annual temperatures were cold enough to maintain positive glacier mass balances. The numerically defined chronologies for the Anyemaqen and Nianbaoyeze Mountains presented here provide a framework for comparing glacial advances in other parts of high Asia. [ABSTRACT FROM AUTHOR]