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The timing of the deposition of the well-preserved Quaternary marine terraces in the coastal region of northeastern Turkey are crucial in understanding the Quaternary tectonics of the Pontides. The chronology of raised marine terraces between Trabzon and Rize has remained unrevealed because of chronologic limitations. This study aims to establish chronology for the terrace deposits by applying optically stimulated luminescence (OSL) dating methods using single aliquot regenerative dose (SAR) techniques on quartz grains extracted from marine terraces. Eleven samples were collected from the lowest three Quaternary marine terraces. The OSL ages clusters into three groups: 52.4 ± 4.6 to 60.0 ± 4.7 ka (terrace level T1); 16.8 ± 0.8 to 33.9 ± 2.8 ka (T2); and 11.7 ± 0.9 ka (T3). This chronology is consistent with the classical terrace stratigraphy; i.e. younger terraces are located at lower elevations and vice versa for the older terraces. We correlate the established terrace chronology with MIS 3c, MIS 3a, and MIS 1. We calculated apparent uplift rates are 0.98 ± 0.12 mm/year, 1.39 ± 0.26 mm/year, and 1.50 ± 0.78 mm/year from marine terrace levels 1, 2, and 3, respectively. Based on the existing eustatic sea-level data/curve, we estimated tectonic uplift rates up to 5 mm per year. Our results indicate that the coastal region of the Eastern Pontides experienced three accumulation periods, with sea-level highstands overprinting the uplifting coastline, and the coastal region of Eastern Pontides has been tectonically active from Late Pleistocene to Early Holocene. This study reveals that marine terraces in the coastal region of northeastern Anatolia might have displaced by the South Black Sea Fault which ultimately points to a regional subsidence with the higher uplift rate, and it points to a differential uplift along the Eastern Pontides. [ABSTRACT FROM AUTHOR]

We present a comprehensive comparison of optically stimulated luminescence (OSL) ages with cosmogenic radionuclide (CRN) ages, and the first study to validate CRN dates from boulders on moraine ridges using luminescence dates from glaciogenic sediments from associated moraines, accomplished from both direct and stratigraphic relationships between CRN and OSL sampling sites. Both quartz and K-feldspars extracted from 12 Late Quaternary glaciogenic sediments were studied using single-aliquot OSL techniques. Rapid signal saturation in preliminary additive-dose infrared-stimulated K-feldspar luminescence growth data was interpreted as evidence of insufficiently bleached latent luminescence, and these data gave rise to overestimated ages in the majority of samples. Further analysis concentrated on replicated single-aliquot regenerative-dose (SAR) measurements of quartz minerals using blue-green stimulation. The SAR sensitivity correction method repeatedly failed in two of the samples and a further sample exhibited significant thermal transfer. Nevertheless, three of the eight glacial successions in the upper Hunza valley were defined using quartz-luminescence. Although we discuss the possibility of inherited components in the CRN data, in terms of paleoclimatic interpretations both dating techniques give concordant results. [Copyright &y& Elsevier]

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]

Moraines along the southwestern slopes of the Qilian Shan were dated using cosmogenic radionuclide (CRN) surface exposure techniques to help define the timing of glaciation in northernmost Tibet. The CRN data show glaciers extending 5-10 km beyond their present positions during the global Last Glacial Maximum (LGM) and probably maintained at their maximum extent until the Lateglacial. These data help support the view that glaciers throughout Tibet and the Himalaya were maintained at or near their maximum LGM extent until the Lateglacial. An optically stimulated luminescence date of 11.8 ± 1.0 ka on silt that caps a latero-frontal moraine shows that glaciers had retreated significantly by the end of the Pleistocene and that loess was beginning to form in this region in response to the changing climate during and after the Younger Dryas Stade. [ABSTRACT FROM AUTHOR]

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]

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]

Glacial landforms and sediments provide evidence for two Late Quaternary major glaciations in the eastern Hindu Kush. New optically stimulated luminescence (OSL) dating was undertaken to define the timing of these glaciations and associated sediment deposition. The Drosh Glacial, was defined by OSL dating to have occurred during marine isotopic stage-3, producing an extensive valley glaciation that extended to an altitude of ⩾1300 m above sea level (asl) in the main valley, with an equilibrium line altitude (ELA) depression of ∼1200 m. The Pret Glacial produced a valley glaciation that extended to an altitude of ∼1670 m asl. in the main valley, with an ELA depression of ∼1000 m. The new OSL dating suggests that this glacial stage probably represents several glacial advances that occurred during the latter part of the Last Glacial. Moraines representing two minor glacial advances, the Shandur and Barum Glacial stages, were also recognized near the contemporary glaciers. These probably formed during the Middle/Late Holocene and Little Ice Age, respectively. This study and comparisons with adjacent regions suggest that there was limited glaciation during the global Last Glacial Maximum (LGM) in the Hindu Kush. Deglaciation in the mountain ranges of the Himalayas and the consequent meltwater discharge into the adjacent seas was negligible immediately after the global LGM and it was therefore of minor importance as a forcing factor for global climate change during the end of the last glacial cycle. However, our studies show that glaciation and particularly deglaciation is important in controlling the deposition of thick valley fills and the landscape evolution of the high mountain environments. [Copyright &y& Elsevier]

The Eastern Pontides (EP), which is the under transpressional deformation zone, is an active mountain belt that has been rising rapidly since the Cenozoic era because of the Arabian-Eurasian convergence. Morphometric studies have been performed to investigate the tectonic activity of this region and better understand the characteristics of the faults geomorphologically; the faults control the mountain fronts in the drainage basin of the EP. The results show the Hypsometric Curve (HC)-Hypsometric Integral (0.37-HI-0.67), Basin-Shaped Analysis (1.2-Bs-7), Valley-Floor-Width to Height-Ratio (0.4-Vf-1.2) and Asymmetry Factor (35-AF-81) applied to 46 drainage basins together with 9 tectonically controlled geomorphic indices (1.2-Smf-1.5) and a Stream Length Gradient (30-SL-120) indicate that the EP is tectonically active, and when the areas are evaluated according to Smf and Vf analyses, the tectonic level is relatively high. According to our conceptual model for the uplifting of the EP, with respect to field studies and morphometric analysis, (i) the EP is the active deformation zone and has a "push-up" geometry in conjunction with the North Anatolian Fault; (ii) the EP is progressively uplifting at a rate of more than 0.5 mm/yr in along with the thrust faults of the Black Sea Fault (BSF) and Borjomi-Kazbegi Fault (BKF). [ABSTRACT FROM AUTHOR]

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]

Ethno-pedology, the systematic definition and classification of indigenous technical knowledge of soil attributes, has often ignored scientific knowledge of soil properties. This paper considers one ethno-pedological class, cesa–goz soils, managed by Kanuri and Shuwa Arab peoples in the Kala–Balge region, northeast Nigeria. Soil micromorphology demonstrates that these soils have been managed in different ways over extended periods, defined by optically stimulated luminescence (OSL) dating. This has resulted in discrete soil types, indicating that ethno-pedological soil classification can be enhanced by integrating it with scientifically defined soil properties and chronologies. These observations carry major implications for the application of ethno-pedology approaches to land management development and the understanding of landscape history. [Copyright &y& Elsevier]

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]