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The inter-comparison of different soil moisture (SM) products over the Tibetan Plateau (TP) reveals the inconsistency among different SM products, when compared to in situ measurement. It highlights the need to constrain the model simulated SM with the in situ measured data climatology. In this study, the in situ soil moisture networks, combined with the classification of climate zones over the TP, were used to produce the in situ measured SM climatology at the plateau scale. The generated TP scale in situ SM climatology was then used to scale the model-simulated SM data, which was subsequently used to scale the SM satellite observations. The climatology-scaled satellite and model-simulated SM were then blended objectively, by applying the triple collocation and least squares method. The final blended SM can replicate the SM dynamics across different climatic zones, from sub-humid regions to semi-arid and arid regions over the TP. This demonstrates the need to constrain the model-simulated SM estimates with the in situ measurements before their further applications in scaling climatology of SM satellite products. [ABSTRACT FROM AUTHOR]

Felsic igneous rocks in the Songxi area are a key part of the Qiangtang Terrane and India–Asia collision zone, and can constrain the evolution of the Tibetan Plateau. This paper presents new geochronological, geochemical, and isotopic data for Early Cretaceous granodiorites (119 Ma), leucogranites (111 Ma), and monzogranites (107–102 Ma) from the Songxi area in the western Qiangtang Terrane. The granodiorites are characterized by enriched Sr–Nd–Pb–Hf isotopic compositions (87Sr/86Sr i = 0.70721–0.70925, ε Nd (t) = −7.6 to −5.6, 206Pb/204Pb i = 18.907–18.964, 207Pb/204Pb i = 15.782–15.825, and ε Hf (t) = −24.0 to −2.0) and are adakitic with low Mg# values (39–44) and high K 2 O contents (2.6–3.9 wt%). The leucogranites have low Sr concentrations (80–100 ppm), high Rb/Sr (2.83–3.53) and low CaO/Na 2 O (0.19–0.22) ratios, high initial 87Sr/86Sr ratios (0.71653–0.71721), and low ε Nd (t) (−12.4 to −11.8) and ε Hf (t) (−18.8 to −6.8) values. The monzogranites are I-type granitoids and have enriched Sr–Nd–Pb–Hf isotopic compositions (87Sr/86Sr i = 0.70956–0.70966, ε Nd (t) = −8.5 to −8.3, 206Pb/204Pb i = 18.740–18.749, 207Pb/204Pb i = 15.759–15.778, and ε Hf (t) = −16.9 to −1.4). Our data suggest that these three types of granitoids were likely generated by partial melting of a thickened lower crust, metapelite-dominated source by fluid-absent muscovite melting, and normal lower crust, respectively. Integration of our new and existing data allows us to conclude that the Songxi granitoids formed in a continental margin arc setting. This further suggests that some sediment-derived leucogranites form in a continental arc setting, and are unrelated to continental collision. Tectonic compression and crustal thickening of the western Tibetan Plateau during the Early Cretaceous occurred when the Bangong–Nujiang oceanic lithosphere was subducted northward at a low angle beneath the western Qiangtang Terrane before ca. 119 Ma. [Display omitted] • The Songxi adakitic granodiorites were derived from thickened lower crust • Some sediment-derived leucogranites can be formed in continental arc setting • The Cretaceous crustal thickening of the western Tibetan Plateau began at ca. 119 Ma [ABSTRACT FROM AUTHOR]

We determined vertical components of slip rates of 0.22 ± 0.03 mm a-1 for the Jiayuguan fault and 0.11 ± 0.03 mm a-1 for the Jintanan Shan fault, which lie along the northeastern edge of the Tibetan Plateau and in the western Hexi Corridor (Northern Qilian Shan, China). We used structural investigations, air-photo imagery analysis, topographic profiling, optically stimulated luminescence (OSL) dating, and 10Be exposure dating. To quantify the slip rates along the faults, we identified and surveyed the well-preserved fault scarps, and we sampled quartz-rich pebbles and cobbles on fan surfaces and within ∼2-m-deep pits to determine surface exposure ages and pre-depositional inheritance. Our slip rates pertain to the past ∼115 ka. They are consistent with previous geological and GPS constraints that suggest that NNE-SSW shortening across the northeastern Tibetan Plateau has been distributed onto several active faults and that shortening is partitioned into low slip rates of 1 mm a-1 on each fault. We infer that the decreasing slip rate from 95 E eastward to the eastern end of the Altyn Tagh fault and the low slip rates of these thrust faults are related. The total shortening in the direction parallel to the Altyn Tagh fault in the Yumen Basin of 0.90-1.43 mm a-1 attests that left-lateral strike slip at the eastern end of the fault has indeed been absorbed by deformation within the Yumen Basin. We infer that the Tibetan Plateau continues to grow northeastward by thrust faulting at low rates and by folding on the northeastern edge of the Hexi Corridor basin. [ABSTRACT FROM AUTHOR]

By combining terrace riser offsets with terrace ages dated by 14C, optically stimulated luminescence (OSL), and 10Be techniques, we determine average slip rates of 1.1 ± 0.3 mm/yr and 1.2 ± 0.4 mm/yr for the Elashan and Riyueshan faults, two northnorthwest-- trending, right-lateral, strikeslip faults west and east of the lake Qinghai in the northeastern margin of the Tibetan Plateau. These faults are conjugate to the major easterly trending, left-lateral Altyn Tagh, Haiyuan-Qilianshan, and Kunlun faults, and they contribute to the subdivision of the region between the Haiyuan- Qilianshan and Kunlun faults into small blocks tens to ~100 km in dimension. The rela tively low slip rates in this region reflect distributed deformation. The total rightlateral offsets of geological contacts are ~9-- 12 km along the Elashan fault and ~11--12 km for the northern segment of the Riyueshan fault. If long-term slip rates were constant during late Cenozoic time, dates of initiation of dextral movement would be 9 or 10 ± 3 Ma for the two strike-slip faults, concurrent with onsets or acceleration of tectonic deformation in Cenozoic basins nearby. Our study highlights a stage of tectonic deformation in the northeastern margin of the Tibetan Plateau beginning since ca. 8--12 Ma, tens of millions of years after the collision between India and Eurasia began. [ABSTRACT FROM AUTHOR]