Eastern Tarim Research Articles

Multi-proxy investigations of Bronze Age diet and environment in the hyper-arid eastern Tarim Basin (Lop Nur), northwest China

Humans have a long history of occupying ecologically marginal regions, and the ancient cultural mechanisms of adaptation to these challenging environments remain poorly understood. We examine archaeological deposits from a Bronze Age settlement in the hyper-arid eastern Tarim Basin (Lop Nur), identifying well-preserved plant remains and bone fragments that shed light on the palaeodiet and past environmental setting. We use the newly developed peptide mass fingerprinting method of ZooMS (zooarchaeology by mass spectrometry) and TimsTOF MS (trapped ion mobility time of flight mass spectrometry) to identify fragments of ancient fish bones as Cyprinidae and possible Salmonidae, indicating both their consumption and the former presence of intra-settlement fresh water-bodies. Remains of littoral and aquatic plants attest to a marshy palaeo-delta at the confluence of the Tarim and Kongque rivers, testifying to a former biodiverse oasis in the Lop Desert when humans occupied the site. We conclude that the use of both aquatic and desert peripheral resources, combined with the intentional management of local environments, were all essential prehistoric adaptations. In addition, we show that radiocarbon dates of aquatic remains have an offset spanning hundreds to thousands of years, due to a freshwater reservoir effect, requiring careful consideration of ages for archaeological bones in the broader region.

Characteristics of Jurassic Source Rocks and Evaluation of Hydrocarbon Resources in Tarim Basin, western China

Jurassic strata in Tarim are significant for their hydrocarbon-rich content. However, the distribution of hydrocarbon source rocks in this region is uneven, and the conditions for hydrocarbon accumulation vary significantly among the different structural elements. Therefore, it is essential to investigate the distribution of Jurassic source rocks, the evolution history of hydrocarbon generation, and the mechanisms influencing hydrocarbon accumulation for effective hydrocarbon exploration and development. To achieve this, seismic, geologic, drilling, logging, and testing data were integrated to analyze the distribution and quality of hydrocarbon source rocks, the evolution of hydrocarbon generation, and the factors influencing hydrocarbon accumulation in Jurassic hydrocarbon source rocks in Tarim Basin. The study revealed that the Jurassic effective hydrocarbon source rock centers are mainly located in the piedmont areas of Kuqa depression, southwest depression, and southeast depression, as well as Yingjisu sag and Manjiaer sag in the eastern Tarim area. Based on a comprehensive evaluation and comparison of the potential of Jurassic hydrocarbon potential in each secondary structural unit, it is concluded that Kuqa Depression has the most favorable exploration zone due to its excellent hydrocarbon accumulation conditions and abundant hydrocarbon resources. Although the overall exploration potential of the southwest depression is lower than that of the Kuqa depression, the hydrocarbon resources potential of the piedmont thrust belt and the associated depression is very high. Similarly, the eastern part of the Manjiaer sag and the Altun piedmont zone of the southeastern depression still have promising exploration prospects, although the overall exploration potential of the eastern Tarim area and the southeastern depression is not as good as the former two.

Evidence for the Late Pliocene Aridification in the Eastern Tarim Basin, Northwest China

Evidence for the Late Pliocene Aridification in the Eastern Tarim Basin, Northwest China

The boundary between the Middle and Upper Cambrian strata in the Tarim Basin, NW China: Regional to global SPICE event correlation

The subdivision and correlation of the Cambrian System have long been controversial globally with multiple schemes. This is especially the case for the Tarim Basin, western China where regional and global correlations of the Middle-Upper Cambrian boundary are hampered by incomplete biostratigraphy. The Middle-Upper Cambrian boundary (T81) in the Tarim Basin is characterized by an abrupt switch of lithological and sedimentary facies, a sudden change of wireline log responses, and the contrasting seismic features, structural styles and carbonate platform architectures. The T81 boundary manifests in various forms and styles including syn-sedimentary unconformity, overlapping unconformity, tectonic unconformity, multi-stage superimposed unconformity, parallel unconformity and conformity. Each manifestation type of the T81 boundary was influenced by at least one of the factors including paleo-geomorphology, tectonic movement, eustacy, and climatic change. Based on the correlation between carbon isotopes and sedimentary characteristics in different regions globally, we suggest that the δ13C weak negative shift that follows the strongly positive shift of the Late Cambrian SPICE event can serve as a reliable isotope stratigraphic marker for identifying the T81 boundary of the western Tarim Platform. The top of the Awatag Formation (the top of the Middle Cambrian) in the western Tarim Platform should thus be correlated to the top of the Mohershan Formation in the eastern Tarim Basin, corresponding to the top of the Miaolingian Stage. The absence of the SPICE event in the western part of the Tarim Basin may have been caused by a regional depositional hiatus associated with the T81 boundary.

Seawater carbon and strontium isotope variations in the eastern Tarim Basin during the Cambrian: Implications for connection with the open ocean

Cambrian was a critical period in Earth's history, marked by rapid diversification of early animals and significant changes in oceanic conditions. Marine sediments, particularly carbonates, have been used to study variations in the global carbon cycle, seawater redox, weathering input, etc. In search of new archives of Cambrian paleo-seawater chemistry, we conducted an integrated study of Cambrian C and Sr isotope stratigraphy using the carbonates of the Xingdi section in the Kruqtagh region of the eastern Tarim Basin. Based on reported paleontological data, the C isotope record is comparable to the Cambrian global seawater C isotope variation, providing a feasible stratigraphic framework for the Cambrian strata in the eastern Tarim Basin. A sharp δ13C increase at the top of the Xidasan Formation probably corresponds to the recovery of the Redlichiid–Olenellid Extinction C isotope Excursion. Additionally, a negative C isotope excursion in the lower part of the Mohuosan Formation and a positive C isotope excursion at the bottom of the Tuersaketagh Formation likely correspond to DrumIan Carbon isotope Excursion and Steptoean Positive Carbon Isotope Excursion, respectively. However, the Sr isotope curve in the eastern Tarim Basin decoupled from global seawater Sr isotope variations during Cambrian Series 2–3 until Furongian, indicating that the eastern Tarim Basin was not well connected with the open ocean until Furongian. It also highlights a significant impact of paleogeographical connections of basins with the open ocean on their seawater Sr isotopic signal.

Teleseismic shear wave splitting and intracontinental collision deformation of the northern Tibetan Plateau and the eastern Tarim basin

Teleseismic shear wave splitting and intracontinental collision deformation of the northern Tibetan Plateau and the eastern Tarim basin

Influence of dissolved organic carbon on the Cambrian Ocean: Evidence from the carbon isotopes of the sedimentary rocks of the Eastern Tarim Basin, North‐west China

In recent years, the typical crude oil from the Cambrian Lower Ordovician source rocks has been found in the Tarim Basin, and it is characterized by 13C enrichment. The stable carbon isotope of the oil is concentrated at approximately −28‰, which is 3‰–6‰ heavier than that of the crude oil from the Middle and Upper Ordovician source rocks. The stable carbon isotope between crude oil and its kerogen is characterized by inversion, with an amplitude of approximately 3‰–4‰. However, the origin of this phenomenon remains controversial, which restricts the next exploration of crude oil in the Cambrian–Lower Ordovician in the Tarim Basin. Samples were collected from seven outcrop profiles in the Kuruketage region. The basic geochemical features of the Cambrian strata, including total organic carbon abundance, δ13Corg, δ13Ccarb, and δ18Ocarb, were studied and compared with those of well TD2. The results show that the lithologies, isotope stratigraphic evolutional curves, and correlations between the organic carbon and inorganic carbon of the profiles from the northern Kuruketage region are successively comparable with those of the profiles from the southern Kuruketage region and the well TD2. In this study, the carbon isotope records are supposed to indicate a vertical gradient Cambrian oceanic mode, including the shallow decoupled isotope zone, middle gradient‐coupled isotope zone, and deep isotope‐decoupled zone. The discovery of this isotope record reflects the formation of stable carbon and oxygen isotope stratified oceans during the Cambrian period. Additionally, it provides important insights into the origin of the 13C enrichment observed in some Lower Cambrian crude oils in the Tarim Basin.

Sedimentary characteristics and depositional evolution of carbonate platform during the Cambrian and Ordovician in eastern Tarim Basin, NW China

Sedimentary characteristics and depositional evolution of carbonate platform during the Cambrian and Ordovician in eastern Tarim Basin, NW China

Characteristics, genetic mechanism, and hydrocarbon accumulation of Cambrian gravity flow in the eastern Gucheng area, Tarim Basin, China

The platform margins of Gucheng and Luoxi in the Cambrian are developed on both sides of the eastern Tarim Basin. Based on the analysis of cores, thin sections, and seismic data of Luoxi platform margin slope areas, we systematically studied the formation condition, reservoir characteristics, and favourable accumulation factors of gravity flow. The types of gravity flow include debris flow, high‐density flow, and low‐density flow, and the high‐density flow reservoir is better. Hydrothermal fluids have an active effect on reservoir reconstruction. Six‐phase reefs are developed in the platform margin, and the lithology of the reservoir is algal framework dolomite and granular dolomite. Multi‐phase reefs form an inclined slope. The 3D seismic and geochemical data show that the platform margin reefs have karst unconformity characteristics. The platform margin slope has the requirements of geomorphology and reservoir source, and the total area of slope gravity flow is 5854 km2. The gravity flow in the Gucheng platform margin slope is near the Cheerchen fault zone, and tectonic movement forms the nose‐like structure. The gravity flow is between the source rocks of the Xidashan Formation and the Heituwa Formation. Hydrocarbon generation and caprock are both favourable for hydrocarbon accumulation. Multi‐phase events of hydrothermal fluids are favourable to the reservoir and hydrocarbon charging. Gravity flow is important for oil and gas exploration in the Tarim Basin.

Key stage and model of hydrocarbon accumulation of Ordovician reservoir in Gucheng area, Tarim Basin, China

The heterogeneity of deep carbonate reservoirs is strong, it is significant for exploration and development to clarify the key stages of oil and gas accumulation. Taking the Ordovician in the Gucheng area of Tarim Basin as an example, this paper systematically investigated the key stage and model of hydrocarbon accumulation using the data of the cores, thin sections, cathode luminescence tests, laser ablation U-Pb isotope geochronometry, bitumen reflectance, and fluid inclusion tests, and seismic interpretation. (1) The Tarim Basin mainly develops three sets of effective source rocks, namely the Cambrian Yuertusi Formation, Cambrian Moheershan Formation, and Mid-Lower Ordovician Heituwa Formation, which are concentrated in the slope-basin facies of eastern Tarim Basin. (2) The Gucheng area is located in a favorable paleo-structural position. The pathway system composed of vertical faults and lateral unconformities occurs in the paleo-uplift, which is critical for hydrocarbon migration and accumulation. (3) The laser in-situ U-Pb dating, distribution and genesis of reservoir bitumen, burial-thermal maturation history, and the homogenization temperature of fluid inclusions suggest that the multi-stage tectonic thermal events of the Caledonian and Hercynian stages result in key adjustment and modification to deep hydrocarbon accumulation. Due to magmatic hydrothermal activities, the Caledonian primary oil reservoir massively evolved into oil-cracking gas reservoirs and residual paleo-oil reservoirs. (4) The paleo tectonic-fluid effect plays an important factor controlling the development of the Ordovician reservoirs. The evolution of the hydrocarbon accumulation in Gucheng area can be divided into three stages, namely formation of primary oil and gas reservoirs, oil-cracking gas reservoirs, and adjustment, destruction and reforming of gas reservoirs. To sum up, the western and northern parts of the paleo-uplift with favorable source-reservoir-cap rock assemblage and less effects of hydrothermal activities are the favorable zones for hydrocarbon exploration in the Gucheng area, the Tarim Basin.

Mechanism of formation and Characteristics of deposition of Cambrian gravity flow in the eastern gucheng area, Tarim Basin

The Gucheng Cambrian margin and Luoxi Cambrian margin is on both sides of eastern Tarim basin. Base on the analysis of cores,thin sections and seismic data of Luoxi slope areas,this paper systematically studies the formation condition, reservoir characteristics and favorable accumulation factors of gravity flow. The gravity flow sedimentary types include debris flow, high density flow and low density flow, debris flow and high density flow reservoir is better. Hydrothermal reconstruction has active effect on reservoir. There are six phases mound-beaches develop in platform margin, reservoir characteristics are algae framework dolomite and granular dolomite. Phases of mound-beaches develop to steep slope. Seismic and geochemical data indicate that the mound-beaches are exposed with corrosion characteristics,the platform margin-slope have the requirements of geomorphologie antique and quality reservoir source.

Aridification in the Asian Interior Recorded by Mineral Assemblages in Tarim Basin since the Late Miocene and Its Link to Global Cooling

Understanding climate change during the relatively warm Pliocene, as compared to the present, offers significant potential for understanding future global consequences of rising atmospheric CO2. Sensitivity differences among various climate proxies lead to divergent interpretations of the driving mechanisms of inland aridification. Minerals as a paleoclimatic indicator with high water-sensitivity can provide effective support for reconstructing climate evolution and clearly understanding driving mechanisms in extremely arid regions. Here we present results of mineral analyses from lacustrine–fluvial Neogene sediments in the eastern Tarim Basin. Evaporite minerals are composed principally of calcite, dolomite, and gypsum, with minor amounts of ankerite and celestite. Clay minerals are dominated by illite and chlorite. We find that evaporite minerals and illite reflect regional climate change through time, and specifically determine the following: (1) climate in the Tarim Basin during the late Miocene was relatively humid, with alternating dry and wet periods from 6.86~5.58 Ma; (2) immediately following that interval, aridification increased rapidly, with reduced regional precipitation that accelerated the shrinkage of the lake; (3) from 4.4 Ma to 3.62 Ma, regional precipitation increased slightly but afterwards, aridification resumed: the climate there has been extremely dry since about 2.7 Ma. Our results show that the climate in the Tarim Basin has followed a global cooling trend since the late Miocene, and suggest that the effect of uplift in the Tibetan Plateau is a secondary influence.

Molecular record of the SPICE event in well YD2, Tarim Basin: Insights from catalytic hydropyrolysis of kerogens

The Steptoean Positive Carbon Isotope Excursion (SPICE) event is extensively documented in globally distributed carbonate and organic-rich successions of slope and platform environments during the late Cambrian (ca. 497–494 Ma). Despite numerous studies, its regional manifestation remains controversial because of the major uncertainty of the redox conditions in sedimentary paleoenvironments and its effect on the changes in the biota. Biogeochemical processes that occurred during the SPICE event are important for assessing whether the excursion is associated with the co-evolution of organisms and environments. In this study, we investigated the changes in plankton and paleoenvironment at the molecular level by combining kerogen elemental analysis, catalytic hydropyrolysis (HyPy), and gas chromatography-mass spectrometry (GC-MS) analyses of saturates and aromatics with published carbon isotopic data. The three fluorene series, gammacerane/C30hopane (G/C30H) and pristine/phytane (Pr/Ph) ratios demonstrated that the shallow shelf seawater changed significantly from relatively reducing to oxidizing and back to reducing conditions during the SPICE interval coupled with a regression-transgression cycle. The phytoplankton during the rise of the SPICE were mainly organic-walled, such as cyanobacteria, various acritarchs, and algae, as evidenced by terpanes, hopanes, and steranes. Significant decreases in phytoplankton diversity and abundance coincided with the peak of the SPICE, corresponding to the most oxidized and hypersaline periods during the SPICE event in the eastern Tarim Basin. Plankton assemblages diversified significantly with increasing living space due to the rise of sea-level during the post-SPICE period. Therefore, this study supports the idea that plankton groups changed dramatically with the environment, and its revolution followed the SPICE into the Great Ordovician Biodiversification Event.

Carbon Isotope Stratigraphy of the Cambrian System in the Eastern Tarim Basin, China

AbstractThe ultra‐deep Cambrian System in the Tarim Basin is an important field for petroleum exploration, while fine division of the Cambrian strata remains controversial. In recent years, carbon isotope stratigraphy of the Cambrian System has been established and widely used. Here, we report an integrated profile of carbonate and organic carbon isotopic values (δ13Ccarb and δ13Corg) from cuttings of the Tadong2 Well in the eastern Tarim Basin. Three carbon isotope anomalies of BACE, ROECE and SPICE were recognized on the δ13Ccarb profile. Three apogees and a nadir on the δ13Corg profile and the onset of ROECE on the δ13Ccarb profile were suggested as boundaries of the present four series of the Cambrian System. Suggested boundaries are easily identifiable on the gamma logging profile and is consistent with the previous division scheme, based on biostratigraphic evidence in outcrop sections. Abnormal carbon cycle perturbations and organic carbon burials during the BACE and SPICE events might be related to the reduction and expansion of a huge dissolved organic carbon reservoir in the deep ocean of the ancient Tarim Basin.

Zircon (U-Th)/He thermochronology and thermal evolution of the Tarim Basin, Western China

• Single-grain ZHe ages of the clastic rocks in Tarim Basin are dispersed with 94 Ma-995 Ma. • The forward and inverse modeling reveals four cooling events since the Neoproterozoic. • The samples experienced several thermal events with the highest temperature of 160–180 ℃. Thermal history reconstruction of the deep and ancient strata (Pre-Silurian) in the Tarim Basin is always difficult due to the lack of effective paleo-thermal indicators. This study provides a new strategy for thermal history reconstruction of the Tarim Basin with the zircon (U-Th)/He thermochronology. The obvious dispersion of the single-grain zircon (U-Th)/He ages for all the clastic rocks in the Tarim Basin reflects the complex and protracted thermal histories. The combination of forward and inverse modeling revealed that the Neoproterozoic rocks from the Kalpin and Bachu Uplifts experienced four rapid cooling events beginning in the Late Ordovician, Late Carboniferous, Late Triassic and Early Miocene, while the Silurian rocks in the eastern Tarim Basin just experienced the Late Carboniferous and Late Cretaceous cooling events. In addition, these rocks experienced several thermal events with the highest temperature of 160–180 °C (a precision of 5–10 °C). The unique thermal histories in the Tabei Uplift and Shunbei area was suitable for the crude oil preservation. This study not only promotes the application of the zircon (U-Th)/He thermochronology in sedimentary basins but also clarify the thermal evolution process of the ancient strata in the Tarim Basin, which plays an important role in determining the deeper source rocks maturation phase and hydrocarbon occurrence state.

The lake-level changes of Lop Nur over the past 2000 years and its linkage to the decline of the ancient Loulan Kingdom

Study regionLop Nur, Xinjiang Province, China Study focusLop Nur has been a vast playa which was a historic lake in eastern Tarim Basin, northwest China. The lake's catchment played a significant role in the development of oasis states in the early Common Era, such as the ancient Loulan Kingdom. However, the history of lake dynamics remains unclear, and its potential linkage to the decline of Loulan Kingdom has been not well-examined. This paper aims to reconstruct the lake-level changes in Lop Nur over the last 2000 years using synthetic aperture radar (SAR) data, optically stimulated luminescence (OSL) dating of lacustrine and aeolian sediments, and radiocarbon (14C) dating of ancient bio-remains. Furthermore, the relationships between Lop Nur' fluctuation and the decline of ancient Loulan Kingdom were discussed New hydrological insights for the regionThe results suggest that Lop Nur once covered an area more than 11, 602 km2 and that lake-level reduced gradually during 360–470 C.E. Subsequently, the lake experienced a few stages of lake-level fluctuation which never reached the upper-most shorelines. Also, the historical changes in the lake level were temporal coincided with the ancient Loulan Kingdom's collapse, showing that the dynamics of hydrological conditions in catchment may have a direct influence on the fall of human settlement in drylands.

Aeromagnetic-Imaged Basement Fault Structure of the Eastern Tarim Basin and Its Tectonic Implication

The property of the magnetic basement and the faults in the basement is significant for structural evolution, the Phanerozoic deposition, and oil resource exploration of the Tarim Basin. Based on the newly acquired aeromagnetic and industry seismic data, we mapped the distribution of basement faults by applying magnetic gradient-processing methods such as the horizontal gradient derivative, the first vertical derivative, the tilt derivative, and the upward continuation method. The dips of basement faults were confirmed and the susceptibilities of basement blocks were obtained by forward modeling of five profiles using the constraint of sedimentary strata depth and Moho topography. On the basis of comprehensive analysis of the magnetic anomalies, the distribution and inclination of basement faults, and susceptibilities differentiation obtained by forward modeling and field measurement, the property of the basement faults and their implication were discussed and interpreted. Our results show that the origin of the Central Highly Magnetic Anomaly Belt is highly magnetic Archean metamorphic rocks. The weakly magnetic Southeastern Domain and highly magnetic Central Tadong Domain assembled along the Tadong South Fault during the Paleoproterozoic. The Paleozoic Cherchen Fault is just an interior fault in the weakly magnetic Southeastern Domain although it presents a large vertical fault displacement. Considering the prominent variation of strikes of the Tadong North Fault system, and the moderately magnetic anomalies in the Northeastern Mangal Domain corresponding to the center of Neoproterozoic deposition, it is likely that the basement of the Northeastern Mangal Domain modified by the Neoproterozoic rifting could be originally the same as the basement of Central Highly Magnetic Anomaly Belt.

Stable Isotopes of Precipitation in the Eastern Tarim River Basin and Water Vapor Sources

The in-situ monitoring of stable hydrogen and oxygen isotopes (δ18O and δ2H) in precipitation is helpful to understand the processes of water phase change, mixing, and transportation. Due to the arid climate in the eastern Tarim River basin, water resources are the key factor affecting the regional sustainable development. However, the understanding of stable hydrogen and oxygen isotopes in precipitation is still limited for this region. Based on the isotope data of 103 precipitation samples collected at four stations in the eastern Tarim River basin from June 2019 to September 2020, the spatial and temporal characteristics of stable hydrogen and oxygen isotopes in precipitation were analyzed, and the connections between stable isotopes and moisture sources were discussed. The findings provide a reference for the application of environmental isotope tracers in arid areas. The results show that, ① the four sampling stations generally presented an increasing trend in precipitation stable isotopic values from north to south, and the isotopic values were higher in summer and lower in winter. The d-excess value in the study region was smaller than the national average, and the slope of the local meteoric water line exhibited a significant arid characteristic. ② There was a positive correlation between precipitation stable isotopes and air temperature in the study region, whereas a weak negative relationship was seen between d-excess and air temperature. The negative correlation occurred between δ18O and relative humidity, and the d-excess value exhibited a positive correlation with relative humidity. ③ The backward trajectory showed that the eastern Tarim River basin is mainly controlled by the westerlies paths. The proportion of air mass that comes from the middle and short distance is relatively large. The concentration weighted trajectory method showed that the farther from the precipitation sampling site, the more stable the d-excess value was. The closer to the sampling site, the more frequently the concentration changed, indicating that the d-excess value was greatly affected by the local water vapor recycling.

Tectono-thermal impacts on the formation of a heavy oil in the eastern Tarim Basin (China): Implications for oil and gas potential

Unraveling the accumulation and alteration process of reservoired petroleum is significant for the evaluation of petroleum potential. In this study, a paleo heavy oil from the TD2 well in the eastern Tarim Basin was investigated through integrated geochemical methods including two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC × GC-TOFMS), gas chromatography-mass spectrometry (GC-MS) and compound specific carbon isotope analysis (CSCIA). Oil-source correlation analysis indicates that the TD2 oil accumulation is “self-generation and self-accumulation” within the Cambrian strata. Combined with tectonic evolution analysis, it is suggested that the oil experienced significant impacts due to changes in tectono-thermal process. Abnormally enriched polycyclic aromatic hydrocarbons (62.5 mg/g in total, 4- to 6- ring account for ~41 %) with few substituents suggest oil cracking due to a short-time high-temperature heating during rapid tectonic subsidence under higher geothermal gradient. Phase fractionation, as indicated by the physiochemical features and heavy isotopic values, was induced by severe tectonic uplift and denudation after accumulation, and resulted in the thickening, re-distribution, and destruction of the primary oil pool. After that, the TD2 oil pool was preserved from further alterations under steady tectonic setting with a low geothermal gradient. Four accumulation assemblages in the eastern Tarim Basin were identified and compared, indicating that great oil and gas potential remains including oil/heavy oil in the Cambrian assemblage and light oil/condensate in the Jurassic and Silurian assemblages. Future exploration should focus on locally developed favorable reservoirs with good preservation conditions.

The Late Quaternary Hydrological Changes in the Eastern Tarim Basin Inferred From 10Be Exposure Ages of River Terraces

AbstractReliable information on the dynamics of hydrological changes is crucial for the social and economic stabilities and sustaining developments in arid Central Asia. However, the few long‐term hydrological records limit understanding of the relationship between meltwater runoff and climate changes, because the short‐term observations show a paradoxical runoff trend with climate warming across Central Asia. Here, we made a systematic analysis on the 10Be exposure ages of the river terraces developed in the eastern Tarim Basin and reconstructed the hydrological regime changes during the past 170 ka. These data, together with the ages of the river terraces in the water source areas, suggest that the exposure ages of river terraces in the eastern Tarim Basin reflect the depositional time of alluvial sediments. The meltwater runoff displays an inverse relation with the North Hemisphere Summer Insolation and temperature changes on both orbital and millennial time scale, indicating that low temperatures favor high runoff fluxes. The observed correlation between the hydrological regimes and temperature changes suggests that the runoff will decrease and thus climate will become drying with global warming in arid Central Asia.