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The 10Be record in laminated travertines is a potential proxy for reconstructing past solar activity down to the annual scale; however, correcting for the potential influence of climatic or environmental variations remains challenging. Here, we present an annually resolved 10Be record using travertines from Baishuitai, China, covering the period from 1510 to 1701 CE, along with environmental proxies, to evaluate climatic influences and implement corrections to accurately reconstruct solar activity. We demonstrate that the 10Be deposition in travertines exhibits two environmental impacts: the transport efficiency of atmospheric 10Be into travertine and the additional 10Be inflow from overland flow associated with rainfall. We show that these impacts can be corrected based on iron and potassium contents. The resulting corrected record agrees with ice‐core and tree‐ring records, demonstrating the feasibility of using such carbonate sediment 10Be records to reconstruct past solar activity. Plain Language Summary: The travertine 10Be record has great potential as a proxy for high‐resolution reconstruction of past solar activity; however, the methodology for correcting the potential influence of climatic or environmental variations has not been fully established. This study presents a new high‐precision annual 10Be record using travertines from Baishuitai, China, covering the period 1510–1701 CE, together with records of environmental proxies, allowing us to evaluate the climatic influences and establish a methodology for correcting them to facilitate accurate solar activity reconstruction. We find that there are two environmental impacts on the deposition of 10Be in travertine: one is the transport efficiency of atmospheric 10Be into travertine, and the other is the additional 10Be inflow from the runoff following rainfall events, and we use iron (Fe) and potassium (K) contents to correct these impacts. The corrected travertine 10Be record exhibits good agreement with ice‐core 10Be and tree‐ring 14C records, supporting that the 10Be record in Baishuitai travertine reliably reflects the atmospheric radionuclide production rate as regulated by solar activity. This result demonstrates the feasibility of using such carbonate sediment 10Be records to reconstruct annual solar activity and suggests the possibility of extending the annual records further back in time than previously obtained. Key Points: A high‐precision annual record of travertine 10Be from 1510 to 1701 CE was obtained to assess its potential as a proxy for solar activityClimatological and environmental impacts on 10Be deposition were found to be correctable based on the content of trace elementsThe travertine 10Be record corrected for climatological impacts reasonably preserves the decadal and centennial‐scale solar cycles [ABSTRACT FROM AUTHOR]

Cosmogenic nuclides contained in the annual layers of natural materials record temporal variations in the galactic cosmic ray flux. 14C in tree rings and 10Be in ice cores from polar regions are often used to retrieve accurate histories of galactic cosmic rays. However, the variation in 14C produced in the atmosphere is strongly attenuated in the carbon cycle and the amplitude of decadal scale variations in tree rings is approximately 0.2‰. In the case of 10Be in ice cores, the variation remains at a relatively large amplitude; however, the records are accompanied by dating uncertainties. Another material that contains 10Be is sediment in continental areas. Terrestrial carbonate deposits sometimes form clear annual layers; however, detailed analyses on such deposits have not yet been widely conducted. Therefore, we evaluate the possibility of retrieving information concerning the galactic cosmic ray flux from the terrestrial carbonate deposits. In this paper, we report our preliminary results obtained from the measurements of 10Be in travertine and tufa samples from South China. We find that the 10Be flux obtained from the travertines is comparable to the level produced by galactic cosmic rays and that travertines might have potential as a tool for investigating past cosmic-ray variations with annual resolution. [ABSTRACT FROM AUTHOR]

Offset geomorphic features and deformed late Quaternary strata indicate active deformation along the Langshan-Seertengshan piedmont fault (LSPF), one of the most active faults in the Hetao fault zone in Inner Mongolia, North China. The widespread occurrence of bedrock fault scarps along the LSPF offers excellent opportunity to examine the faulting history. Using cosmogenic Be exposure dating, we measured the exposure ages of the western Langshankou scarp, located in the middle segment of the LSPF. Our data revealed at least two earthquakes that occurred at 22.2±3.3 ka and 7.2±2.4 ka, respectively. These events are consistent with previous paleoseismic trench studies. The regression of the relationship between the age and sampling height along the scarp yield a fault slip rate of 0.10 +0.05/-0.06 mm/yr, which is significantly lower than the average post-late Pleistocene fault slip rate of ~1 mm/yr, as estimated from the offset of the T2 terraces by previous studies. This indicates that the slip of the LSPF may have been accommodated by other fault branches. [ABSTRACT FROM AUTHOR]

The Pliocene fluvial/lacustrine sediments of the Sanying Formation lie along the Red River fault and its northwest extension; their majority outcrops appear around Eryuan. The Sanying Formation is characterized by multiple intercalated coal layers and its unconformities contact with the underlying Triassic limestone and the overlying Quaternary coarse sediments. Cosmogenic nuclide burial dating confirms the Pliocene age of the Sanying Formation. The burial ages of the overlying Quaternary sediments provide the lower age limit of the Sanying Formation: 2 Ma. Detrital zircon U-Pb age distribution suggests provenance of the Sanying Formation traced to the Songpan-Ganzi flysch belt. From the spatial distribution as well as sedimentary and fault ages, we found a strong connection of the Sanying Formation with the Red River and the Jianchuan faults. We therefore propose that activation of the Red River and the Jianchuan faults during the Late Miocene resulted in subsidence of basins in the extensional areas around Eryuan and in the middle to south segments of the Red River fault. The basins were filled with water carried by the Jinsha River and overflow-lakes formed within the basins where the Sanying Formation was deposited. Most of the lakes were dried and sedimentation of the Sanying Formation ceased due to the uplift of the Yunling Mountains, which forced rerouting of the Jinsha River at the beginning of Quaternary. [ABSTRACT FROM AUTHOR]

Abstract: Collision between the Indian and the Eurasian plates since the early Cenozoic produces one of the world’s most remarkable continental escarpments between the Tibetan Plateau and the adjacent Sichuan Basin. Yet Tertiary sediments are rare in the Sichuan Basin; the oldest preserved Late Cenozoic deposits called Dayi conglomerates directly overlie the Cretaceous or Jurassic red beds. Using cosmogenic 10Be and 26Al burial dating, we obtain deposition ages of ∼2.0 Ma and catchment erosion rates of ∼400 mm/ka for the Dayi conglomerates. Zircon U–Pb age distributions suggest derivation of these conglomerates from the Songpan-Ganzi flysch, the Pengguan complex and Late Permian and Triassic granite plutons in the headwater regions of the Min Jiang (Jiang, a Chinese term, means river). The formation of the poorly-sorted, sub-angular to sub-rounded and tens-centimeter-sized deposits in the western margin of the Sichuan Basin, after long distance transportation, is best explained by glacial activity ∼2.0 Ma ago in east Tibet. [Copyright &y& Elsevier]

Abstract: We have used in situ produced cosmogenic nuclides 10Be and 26Al to date lacustrine shorelines around eight lakes in Tibet. Two lakes located south of the Yarlung Tsangpo River discharged at high lake levels. One of them, Drolung Co (Co is a local term, meaning lake), became closed (its water level fell below its outlet channel) at ∼3.8ka and lowered over 120m vertically since then. This implies a significant change in intensity of precipitation driven by the Indian monsoon over southern Tibet in the middle-late Holocene. Nam Co and Dajia Co, located to the north of the Yarlung Tsangpo River, also drained at high lake levels and became closed ∼53–36ka and ∼48ka, respectively. Of four other lakes developed closely in the Qiangtang basin, north of the Yarlung Tsangpo River, Tangra Yum Co and Siling Co (located at 31–32°N) show exposure ages for high lake shorelines of over 220ka, the oldest lake shorelines reported for Tibet, while towards the north and west, the high lake of Zhari Nam Co appeared after the Last Glacial Maximum (LGM). The different pattern of lake development to the north of Yarlung Tsangpo River may reflect regional climate effects. [Copyright &y& Elsevier]

Abstract: The Daju and Lijiang-Daju fault zones which bound the Yulong Mountains on its northern and eastern perimeters, respectively, are segments of a continuous fault system that bends at Daju. Uplift of the Yulong Mountains, the southernmost glacierized mountain range in Eurasia, resulted from the normal faulting characteristics of the fault system. Using cosmogenic surface exposure dating with 10Be and 26Al, we have measured bedrock exposure ages as a function of elevation along an exposed bedrock scarp of the Daju fault. 10Be and 26Al exposure ages increase monotonically with elevation ranging from 2.6 to 9.6ka over the 51m scarp length giving an average dip-slip rate of 7.5m/ka during the Holocene period and a vertical uplift rate of 5.7m/ka. The 5.7m/ka Holocene uplift rate and supporting geomorphic features suggest that the uplift of the Yulong Mountains mainly occurred in the Quaternary. The fast slip rate and seismic quiescence for the recent 2.8ka call attention to the possible recurrence of large magnitude earthquake events along the fault zone. [Copyright &y& Elsevier]

Abstract: Glacial deposits are present at the head of the Ürümqi River valley, Tianshan, Central Asia. 10Be surface exposure ages of 15 boulders from three sites along a 12 km valley transect range from 9 to 21 ka suggesting emplacement by glacial retreat and advance commencing at the global last glacial maximum (LGM) and most likely abating in the early Holocene. Although the age spread for a given locality is not small, perhaps indicating post-depositional reworking, maximum ages per site are either coeval with or are post-LGM and inconsistent with previous pre-LGM electron spin resonance ages. [Copyright &y& Elsevier]

Abstract: Hundred-meter-thick lacustrine sediments are widespread along the Middle Yangtze River. The distribution of these sediments suggests that an event blocked the river, forming a lake stretching 160 km from east to west and 110 km north to south, with a depth of ≥500 m. Using the cosmogenic nuclides 10Be and 26Al we have dated the time of burial of the lacustrine sediments and fluvial gravels beneath the sediments. Our results indicate a deposition age for these sediments between 1.34 and 1.58 Ma. Studies of zircon U–Pb age distributions within lacustrine sediments and fluvial sands related to the paleo-lake formation show diverse provenances from the upper Yangtze River and Yalong River, a major tributary of the Yangtze River. These deposits contain geologic fingerprints that allow identification of the source region of the lacustrine deposits and fluvial sands. Our results support the reversal of the Middle Yangtze River before the paleo-lake formation. We hypothesize that the geologic event that dammed the originally southward flow was the lateral movement of Chenghai fault in the Dali fault system initiated in early Quaternary. Water eventually cut through the spillway and flowed to the east. [Copyright &y& Elsevier]

The basin history of the northeastern Tibetan Plateau provides an ideal record for understanding the tectonic evolution of the plateau. We present high-resolution magnetostratigraphy and cosmogenic 10Be/26Al burial chronology from the Tongxin Basin in the Arcuate Ranges area in the northeastern Tibetan Plateau and reconstruct a long depositional history ranging from >21.7 to 4.6 Ma. Our new chronologic data suggest that a broad N-S-trending elongated basin existed during the Late Oligocene-Early Miocene (>21.7–16.5 Ma). WNW-trending faulting initiated at ca. 16.5 Ma and resulted in the formation of some fault-bounded basins outward from the western margin of the broad basin, but did not strongly affect the deposition within the basin region. Subsequently, intense northeastward compression elevated both WNW- and NWN-trending mountain ranges at ca. 7.6 Ma. Thrust-induced surface uplift elevated basin sediments and formed piggy-back basins in the hanging-wall blocks, reflecting the northeastward expansion of the northeastern Tibetan Plateau. • A sedimentary history ranging from >21.7–4.2 Ma is revealed in the Tongxin Basin. • A broad basin region developed in 21.7–7.6 Ma in the NE Tibetan Plateau. • Significant NE compression altered the predominant basin region at ca. 7.6 Ma. • The basins provide insights into the expansion pattern of the NE Tibetan Plateau. [ABSTRACT FROM AUTHOR]

The northern Qinling Mountains stretch from east to west in Central China. They have undergone distinct surface uplift during the Late Cenozoic and have become the geographical boundary between northern and southern China. To investigate the topographic evolution of the northern Qinling Mountains over millennial timescales and to explore the major controlling factors of relief development we have calculated 10Be-derived catchment-averaged erosion rates. Results show that the catchment-averaged erosion rates ranged between ~67.4 and 327 m Ma−1. These erosion rates are nonlinearly correlated with topographic parameters, indicating that topographic steepness controls the spatial variability of the erosion rates. Comparison of local erosion rates reveals that lithology and precipitation have limited influence. Instead, the spatial distribution of erosion in the northern Qinling Mountains is primarily controlled by active tectonics, which can be attributed to uplift along the Qinling Piedmont Fault and the Taibai Fault. Due to the intensive tectonic activity of the Qinling Piedmont Fault since the Late Miocene, the Heihe River Basin has developed as a transient landscape. Finally, comparison between the vertical fault slip rates of the Qinling Piedmont Fault and erosion rates indicates that the topography of the northern Qinling Mountains has undergone continuous uplift and growth since at least the Late Pleistocene. Our results suggest that the northeastward growth of the Tibetan Plateau has regulated the modern erosion of the northern Qinling Mountains and shaped their modern topography. • Study of topographic evolution in the northern Qinling Mountains, E Tibetan Plateau • Analysis of 10Be catchment erosion rates combined with river long profile metrics • Erosion rates relate to active tectonics along the Qinling Piedmont and Taibai Faults • Fault-related uplift drives transient incision of the Heihe River • Late Cenozoic topographic development linked to Tibetan Plateau NE growth [ABSTRACT FROM AUTHOR]

Age is of great significance to understanding the causes of landslide instability and movement, and therefore, it is important to know when conducting a hazard assessment. To date, no detailed and comprehensive determination of the age of the Mahu giant landslide has been conducted. The Mahu giant landslide is located in the lower reaches of the Jinsha River and has a volume of 2.38 km3 and a maximum elevation difference of 1080 m, making it the largest subaerial landslide found to date in China. In this study, we report the age of the landslide based on 36Cl exposure dating. Ten cosmogenic nuclide samples were collected from boulders on the landslide deposits and the bedrock on the landslide's scarp, and eight valid ages were derived in the range of 11.63 ± 0.96 to 29.14 ± 1.81 ka. Based on the lithologies and ages of the landslide's scarp and the deposits, the landslide is concluded to have been formed by two major events, with error weighted mean ages of 14.75 and 25.21 ka. The age results for the Mahu landslide obtained in this study provide a basis for understanding the causes of the Mahu landslide. Moreover, this case study indicates that the regional fault activity and earthquake risk can be analyzed from the perspective of landslide science. • Tested the accurate age of the Mahu giant landslide with the 36Cl exposure dating method. • Divided the Mahu landslide into two major events, with error weighted mean ages of 14.75 and 25.21 ka. • This study provides an evidence for further analysis of regional fault activity and earthquake risk. [ABSTRACT FROM AUTHOR]

In situ cosmogenic nuclides are widely employed to quantify topographic and geomorphic landscape evolution. However, few studies are devoted to investigating possibly unsteady denudation. In this work the denudation rates of five surface bedrock and one depth profile are measured using in situ cosmogenic 36Cl in different climate zones in China; cosmogenic 36Cl is a powerful proxy for the surface denudation processes of carbonate landscapes in different climatic gradients since carbonates are more sensitive to climate change than silicates. Compiling previous worldwide surface denudation studies in different gradients, we find that: (I) denudation rate increases systematically with mean annual precipitation (MAP) in arid climatic zones (MAP lower than ~700 mm yr−1) and is dominated by long-term climatic gradients; (II) humid climatic zone (MAP greater than ~700 mm yr−1) denudation rates are about constrained to 34.1 ± 11.7 mm kyr−1 by carbonate dissolution kinetics; and (III) denudation rate is also influenced by short-term physical erosion or abrupt erosive events. Accordingly, the reconstructed evolutionary history of the Guizhou depth profile results from either a relatively high denudation rate (55.5 –4.4 +5.6 mm kyr−1) and long duration exposure (274 –147 +120 ka), or an alternative a low denudation rate (0.8 –0.8 +13.3 mm kyr−1) and a recent abrupt erosive event (13.0 –1.6 +1.9 ka). These two possible solutions suggest that assumed long-term averaged denudation rate can conceal episodic erosion events. Given tectonic quiescence we propose that climate change might mainly control an erosive event during the last glacial termination (~14 ka), which also implies that caution should be taken when determining the denudation rate of a landscape where climate change and/or tectonic activity plays an important role. [ABSTRACT FROM AUTHOR]