Lunpola Basin Research Articles

Neogene surface uplift of the Lunpola Basin in Central Tibet: Implications for uplifting and flattening of orogenic plateaus

Orogenic plateaus are known for their high and flat interiors, but the mechanism by which the high-elevation, low-relief topography is formed remains controversial. The Tibetan Plateau, which may have had a broad central valley along the Bangong suture zone during the Eocene, is a valuable research target to test potential driving mechanisms. In this study, we report both stable and clumped isotopes of lacustrine carbonates of the Lunpola Basin to better constrain the paleoelevation history of the Bangong suture zone in Central Tibet. Covariations of the stable oxygen and carbon isotopes indicate increasing evaporative enrichment of lake water reflecting enhanced aridity from the middle Eocene to early Miocene. After removing altered samples using multiple diagenesis screening methods and the potential influence of global cooling, our clumped isotope temperatures indicate consistent paleoelevations of 2.2 ± 1.1 km at 40–20 Ma, followed by an abrupt 1.4 ± 0.8 km surface uplift at 20–19 Ma and an additional 1.0 ± 0.7 km surface uplift between 16 Ma and the present to achieve the current high elevation of ∼4.6 km. These new paleoelevation results suggest that the Neogene was the primary period of topographic growth for the Lunpola Basin, which contradicts previous inferences emphasizing Paleogene growth. We argue that the Bangong suture zone in Central Tibet was probably a broad low-elevation valley throughout the Paleogene and uplifted mainly during the Neogene by multiple subsurface geodynamic processes, including convective removal of the lower lithosphere and middle–lower crustal flow. A comparison with the north-central Tibet Hoh Xil Basin and South American Altiplano indicates that these subsurface geodynamic processes may be common for uplifting and flattening orogenic plateaus.

Spatial heterogeneity of Cenozoic provenance in the Nima and Lunpola basins of China: Implications for the origin of the low-relief topography in central Tibet Plateau

The central Tibet Plateau is characterised by low-relief topography of high elevation; however, the origin of this surface flatness is uncertain because of a lack of reliable evidence from palaeogeography and palaeodrainage. In this study, we conduct sedimentological and provenance analysis of the Nima Basin, one of several terrestrial basins developed along the Bangong–Nujiang suture zone since the middle Eocene. Our data show that the Dingqinghu Formation in the Nima Basin was deposited in fan delta, braided river and lacustrine environments in the late Eocene after 37 Ma. It received sediment consisting mainly of recycled detritus, including orbitolinid-bearing limestone with volcanic fragments from the Lhasa Terrane in the south. Comparison of the stratigraphic sections in the Nima Basin with those of the adjacent Lunpola Basin suggests that these regions are characterised by local but similar provenance signals. We suggest that a source-to-sink system once existed from the shallower Nima Basin eastward to the deeper and bigger Lunpola Basin. We hypothesise that the Oligocene–early Miocene source-to-sink system from the Nima to Lunpola may have played a role in the surface flattening of the central Tibet Plateau.

Controls on organic matter enrichment of the early-middle Miocene lacustrine oil shale, central Tibet (SW China): New insights from clay minerals and geochemistry

The Lunpola oil shale is the largest lacustrine oil shale deposit in Tibet (SW China), which deposited in a Cenozoic lacustrine rift basin and contains abundant organic matter (OM), whereas the crucial factors that controlled the OM enrichment remain elusive. Here, we present new datasets of total organic carbon (TOC) contents, clay minerals and whole-rock geochemistry of the early-middle Miocene Middle Dingqinghu Formation oil shale from the Lunpola basin, central Tibet, in order to elucidate the paleoclimate, paleo-environment condition and the controlling factors on the OM enrichment of the lacustrine oil shale.Oil shales from the Lunpola East section have high TOC contents (avg. 9.60%), while the contiguous mudstones contain low TOC contents (avg. 0.44%). During the oil shale deposition, high smectite and kaolinite contents, low illite contents and low Sr/Cu ratios suggest strong chemical weathering and hence warm and humid climate, which may probably have close relationship with the mid-Miocene climatic optimum (MMCO). However, during the mudstone deposition, the relatively high illite and low smectite contents and higher Sr/Cu ratios suggest weak chemical weathering, indicating relatively arid climatic condition. The paleo-environment indexes (Corg/P, MoEF and UEF) and MoEF-UEF covariation reflect an anoxic bottom water condition during the oil shale deposition, while the mudstone formed in oxic-dysoxic water environment. The weak and moderate positive relationship between bio-productivity proxies (P/Ti and Cu/Ti ratios) and TOC contents reveal that the bio-productivity condition is not the crucial factor for the OM enrichment. Moreover, the water column environment was brackish and stratified during the oil shale deposition, and the sedimentation rate was moderate, which were also conducive to the OM preservation. The positive correlations between the TOC and the paleoclimate and paleoenvironment proxies demonstrate that warm and humid climate during the MMCO and anoxic water conditions play predominant roles in OM enrichment of the Lunpola lacustrine oil shale. Besides, modest sedimentation rate can prevent the dilution of OM, which can also promote the OM enrichment. This study can not only deepen the understanding of OM enrichment mechanism in lacustrine rift basin but also provide important information for predicting the distribution of the oil shale in the Lunpola Basin.

Development of reference material for multiple methods: A case study on tuff from Dingqinghu Formation in Lunpola Basin, Tibetan Plateau

Development of reference material for multiple methods: A case study on tuff from Dingqinghu Formation in Lunpola Basin, Tibetan Plateau

Cold climatic snaps during the Eocene-Oligocene transition in the central Tibetan Plateau: Implications for ice-induced sedimentary structures and isotope geochemistry

The Eocene-Oligocene transition was a time of major climate instability and a shift from an ice-free world to a predominant icehouse climate. Identifying the ancient glacial deposits and their associated sedimentary structures are of paramount significance for understanding the Earth's climate in the Cryogenian Period. Ice-induced sedimentary structures (IISS) are considered as types of primary structures preserved on surfaces and in upper parts of unconsolidated sediments by physical cryospheric processes of seasonal ice freezing and thawing, and therefore sensitive not only to climate, but also to paleogeography, hydrology, and type of environment. Despite the common occurrence of modern IISS in a wide variety of environments, from high-latitude regions to low-latitude areas of high altitude, available records from ancient geologic archives are scarce. Herein, we integrated sedimentological and geochemical proxies to study IISS and geochemical signals as reliable indicators of cold climate in an outstanding example of the Eocene-Oligocene interval from the Niubao Formation in the Lunpola Basin, central Tibet. Detailed field sedimentological, petrographic microscopic investigations, and bulk carbonate oxygen (δ18Ocarb) and carbon (δ13Ccarb) isotope geochemistry were conducted in this lacustrine succession. Seven sets of IISS are represented by ice crystal marks, frozen cracks, ice-frozen bubbles, ice-expanding laminae, ice-rafted debris (dropstones), ice water pea-like, and ice water pits. They are classified into three groups based on major deriving mechanisms: ice-related crystal marks, deformation-related ice structures, and gravitational fall IISS. Positive δ18Ocarb excursions at the Eocene-Oligocene transition provide evidence of a shift toward cold or near-freezing climatic snaps in response to global cooling episodes at this time. Integrating the paleogeomorphic scenario of central Tibet with the stratigraphically reported IISS and glendonite clusters, the results support that the Lunpola lake sustained cold or near-freezing conditions at Eocene-Oligocene transition. These findings provide one of the most comprehensive sedimentological and isotopic analyses of ancient IISS and a more direct spatial-temporal constraint for the regional climate system of central Tibet.

Late Oligocene monsoonal climate in the Lunpola Basin, central Tibetan Plateau: evidence from palaeosol records

The Asian monsoon affects the natural patterns of climate in China and its origin and evolution have been a matter of much debate in palaeoclimatology. Results from recent studies indicate that the Asian monsoon had reached the subtropical zone by at least c. 41 Ma and expanded to the central Tibetan Plateau during the Late Oligocene, although more geological evidence is required to confirm its spatial and temporal evolution. The well-developed Late Oligocene palaeosol in the Lunpola Basin, central Tibetan Plateau is an ideal material for addressing the issue. Observations of various climatic indicators suggest that these palaeosols were forest cinnamon soils, as shown by the compound Bt and Bk horizons, abundant clay coatings and carbonate nodules, and the diagnostic chemical composition of clays in the Bt horizon. A high chemical weather index, the Rb/Sr ratios and high contents of illite/smectite mixed-layer minerals show that these palaeosols experienced intense weathering and leaching during pedogenesis. The mean annual temperature and mean annual precipitation during the developmental period of the palaeosols were 10.4–14.8°C and 615–1128 mm, respectively, as estimated by empirical formulas, which are comparable with those of cinnamon soils in current monsoon climates. This study provides important independent evidence from palaeosols for studies of the evolution of the Asian monsoon. Supplementary material: The data about the clay chemical composition and climatic indicators of palaeosol and modern soils are available at https://doi.org/10.6084/m9.figshare.c.6850703 Thematic collection: This article is part of the Mesozoic and Cenozoic tectonics, landscape and climate change collection available at: https://www.lyellcollection.org/topic/collections/mesozoic-and-cenozoic-tectonics-landscape-and-climate-change

Research progress on the age, paleoenvironment, and paleo-elevation of Cenozoic strata in the Lunpola Basin, Central Tibetan Plateau

Research progress on the age, paleoenvironment, and paleo-elevation of Cenozoic strata in the Lunpola Basin, Central Tibetan Plateau

Identification and origin of the Late Oligocene to Miocene pyroclastic rocks in the Lunpola Basin and link with deep geodynamics in the Lhasa terrane, Tibetan Plateau

Identification and origin of the Late Oligocene to Miocene pyroclastic rocks in the Lunpola Basin and link with deep geodynamics in the Lhasa terrane, Tibetan Plateau

Climate‐induced organic matter enrichment in lacustrine basin: Insights from the Palaeogene–Neogene oil shale in the Lunpola Basin (Tibet, China)

Lacustrine rift basins are ideal continental settings for understanding organic matter (OM) accumulation mechanisms, because lacustrine deposits are most sensitive to variable climatic and palaeoenvironmental conditions. The Lunpola Basin is a Cenozoic lacustrine rift basin with widespread oil shale depositions that provide a valuable example of triggering factors that controlled OM accumulation. In the investigated interval of the basin, high Si, Ti, Zr, Th, Al and rare earth element concentrations suggest high clastic fluxes during the oil shale deposition. These high clastic fluxes could be attributed to warm and humid climates due to high values of ln(Al2O3/Na2O) and C‐value (Ʃ (Fe + Mn + Cr + Ni + V + Co)/Ʃ (Ca + Mg + Sr + Ba + K + Na)). The Lunpola shales and oil shales were deposited in saltwater environments under enhanced dysoxic to anoxic conditions with high palaeoproductivity. In the Lunpola Basin, climate warming can be subdivided into two different stages based on C‐value and ln(Al2O3/Na2O) variations. Each stage is consistent with an increase in the primary productivity of the palaeolake. Thus, a model for climate‐induced OM enrichment in lacustrine rift basins is proposed, which indicates that climate and primary productivity are the key factors controlling OM accumulation.

Eocene–Oligocene glaciation on a high central Tibetan Plateau

Abstract The nature of glaciation (bipolar vs. unipolar) during the Eocene–Oligocene transition (EOT) remains unresolved. Here, we report the occurrence of frost marks, ice-rafted debris (IRD), and glendonites from the Upper Eocene to Lower Oligocene Niubao Formation (Fm.) deposited in a proglacial lake above glaciolacustrine conglomerates and diamictite facies in the Lunpola Basin, central Tibetan Plateau (CTP). Magnetostratigraphy dates these cryospheric deposits to ca. 36.2–31.8 Ma, synchronous with a stratigraphic interval containing IRD offshore of SE Greenland and in the Barents, Chukchi, and Laptev Seas, suggesting a strong continental-oceanic coupling. Our results provide robust continental evidence for intermittent cryospheric processes in the midlatitude Northern Hemisphere during the late Eocene and EOT. The global cold snap EOT-1 influenced already glacierized high-altitude mountains, lowering equilibrium line altitudes (ELAs) of glaciers and leading to local development of ice fields, ice caps, and valley glaciers with proglacial lake systems, such as the one recorded in the Niubao Fm. The record of IRD, glendonites, and frost marks before the onset of EOT-1 points to an active cryosphere on a plateau already elevated by ca. 36.2 Ma.

Hydrocarbon accumulation conditions and favorable exploration zones in the Lunpola Basin, Tibet

By systematically reviewing and summarizing the previous studies on the petroleum geology of the Lunpola Basin, combined with the latest oil and gas exploration results, the oil and gas accumulation conditions of this basin are summarized, and the favorable zones with the most exploration potential are pointed out. The results show that: ① The Paleogene mainly develops three sets of source rocks, including Niu-1 section, Niu-2 section and lower Niu-3 subsection. The lithology is mainly semi-deep and deep lacustrine gray-dark shale. Among them, the source rock of Niu-2 section is the best. However, the source rock of Niu-1 section is only developed in the Jiangjiacuo depression. The effective source rocks have the largest thickness in the central and western parts of the basin and have the best hydrocarbon-generating capacity. The thickness and abundance of the source rocks have decreased eastward. The organic matter are mainly Type I and Type II1, with a maturity of 0.58%–1.08%. ② The study area is dominated by clastic rock reservoirs, which can be divided into three types according to the strata distribution, and the overall reservoir conditions are not good. The reservoir porosity is between 0.1% and 32.6%, mainly between 2.0% and 10.0%, with an average of 6.5%; the permeability is between 0.0005 mD and 116.0 mD, mainly between 0.01 mD and 0.5 mD, which means ultra-low porosity and ultra-low permeable fracture-porous reservoirs. ③ Three sets of seals are mainly developed in the Lunpola Basin, including two regional seals of the middle Niu-2 subsection and Dingqinghu section, and a direct seal of upper Niu-2 subsection. These three sets of seals are well developed and have good preservation conditions in the relatively stable central depression and the footwall of thrust nappe structural belt . ④ The oil and gas reservoirs in the Lunpola Basin have the distribution law of “structural traps in the north and south, and lithologic traps in the center”. Structural traps are mainly distributed in the thrust nappe belt in the north and the Changshan uplift in the south, forming “self-generation and self-storage” or “lower-generation and upper-storage” reservoirs. While lithologic traps are mainly distributed in the central sag, forming “self-generation and self-storage” reservoirs. ⑤ The source-reservoir-caprock combination conditions are good in the structural traps in the footwall of the northern thrust nappe belt and the lithologic traps in the southern slope belt of Jianjiacuo depression,, and they are the most favorable oil and gas exploration zones in the Lunpola Basin.

Middle Miocene paleoenvironmental change and paleoelevation of the Lunpola Basin, Central Tibet

The Tibetan region underwent diachronous differential rises during the Cenozoic era. Its elevation history is critical for understanding the processes of mountain building, and for evaluating its climatic effects on atmospheric circulations. However, knowledge of paleoenvironment and paleoelevation in different geological domains of the Tibetan Plateau is still limited. Here we provide chronology of lacustrine deposits of the Upper Dingqing Formation in the Lunpola Basin in Central Tibet, which yields a middle Miocene age (15–12 Ma). Both stable isotope and palynological records indicate a climatic transition at ∼13.8 Ma marked by a change towards a cooler and drier climate after the Middle Miocene Climate Transition driven by global climatic cooling. Pollen and spore assemblages suggest that the vegetation was dominated by mixed coniferous–broadleaved forest with some grasslands. New palynological elevation reconstructions constrained by the co-existence approach yield a maximum paleo-elevation of 3100–3600 m (average 3350 m) of the Lunpola Basin, which was consistent with a maximum elevation of 3400 m based on floating-leaf plants. Our new data do not support previous views that the Lunpola Basin achieved its current elevation as early as the late Eocene or early Oligocene, but instead we suggest there has been a rise of up to 1200 m since 12 million years ago. Our results bring new light on both the paleoenvironmental reconstructions and the paleo-elevation estimates of the Lunpola Basin, Central Tibet.

Detrital zircon U-Pb geochronology of the Lunpola basin strata constrains the Cenozoic tectonic evolution of central Tibet

The Cenozoic tectonic evolution of central Tibet plays an important role in the growth of the Tibetan plateau. Paleoelevation studies show that the central Tibetan plateau hosted an east-west trending belt of basins in the Paleogene, but how they relate to the regions uplift history remains unclear. This study addresses the uplift history of the central Tibetan plateau by focusing on Lunpola basin strata deposited in the Cenozoic through detrital zircon basin provenance and zircon geochemical indicators for crustal-thickening. U-Pb dating of detrital zircon demonstrates that the Lunpola basin was mainly derived from mixed sources composed of Paleozoic–Mesozoic sedimentary rocks of the Lhasa terrane, the Cretaceous igneous rocks of the northern Lhasa terrane, and the Paleozoic–Mesozoic sedimentary rocks of southern Qiangtang terrane. The modal framework-grain composition of sandstone samples from the basin strata indicates a recycled orogen as the source. Sandstone composition analysis reveals an increase in the volcanic component with time associated with a pulse of quartz grains in the middle Eocene. We interpret such observations to indicate input from early Cretaceous clastic sediments belonging to the Duba Formation and the Baingoin Plutonic Complex, which imply passive exhumation along the hanging wall of the Gerze-Siling Co thrust. Trace element geochemistry of zircon grains demonstrates an increase in europium anomaly (Eu/Eu*), which we interpret to reflect ∼20 km crustal thickening in central Tibet from the Eocene to Oligocene, as well as an increase of >3 km surface elevation which partly was induced by the Cenozoic sedimentary accumulation. This significant uplift event may have been associated with convective removal of a thickened Tibetan lithosphere that in turn led to magmatic inflation of the Tibetan crust.

Podocarpium (Fabaceae) from the late Eocene of central Tibetan Plateau and its biogeographic implication

Podocarpium is an extinct genus in Fabaceae with rich fossil records in Eurasia dating back to the Eocene. However, the diversification and biogeographic histories of Podocarpium are poorly known due to a lack of fossils in some key regions, such as the Tibetan Plateau, an area recently shown to be crucial for floristic exchanges worldwide in the geological past. Here, we describe well-preserved fossil pods of Podocarpium from the late Eocene (~35 Ma) of the Lunpola Basin, central Tibetan Plateau, China. Together with detailed morphological observation and geometric morphology analysis, these fossil pods are named Podocarpium tibeticum W.-C. Li, J. Huang et T. Su sp. nov., characterized by asymmetrical elliptical valves, olecranon fruit beak, and a clearly oblique base. This material comprises the oldest fossil record of Podocarpium from the Tibetan Plateau and adjacent regions. The discovery of P. tibeticum shows Podocarpium was present in central Tibet by the late Eocene. Together with previous fossil records, it indicates that Podocarpium may have originated in East Asia, migrated into the central valley of Tibet in the late Eocene, and then spread westward to Europe through a low-latitude path of island chains along the Neotethys. Results of paleoecological niche modeling demonstrate that Podocarpium had an almost worldwide potential distribution range in the Eocene, but this sharply contracted thereafter until by the Pliocene it was restricted to a small area of East Asia. Generally, this finding further supports the idea that what is now the central Tibetan Plateau was a globally significant hub for Paleogene floristic exchange.

Orbital Forcing of Climatic Changes on the Central Tibetan Plateau Reveals Late Oligocene to Early Miocene South Asian Monsoon Evolution

AbstractThe uplift of the Tibetan Plateau (TP) is generally considered to have triggered the Asian monsoon system. However, a long‐standing scarcity of high‐resolution paleoclimatic records on the TP makes it unclear when the South Asian monsoon (SAM) reached the central TP. Here, we investigated the environmental magnetic properties of a lacustrine sequence (∼25.5–19.8 Ma) from the Lunpola Basin. Hematite is the dominant magnetic mineral with concentrations that vary with “box‐shaped” peaks that mainly resulted from preferential preservation and dissolution of detrital iron oxides in alternating nonsteady state redox environments. Environmental magnetic sequences reflect distinct dry‐wet cycles with a ∼400 kyr eccentricity periodicity, which are proposed to have been driven by SAM intensity. Therefore, our study reveals that the SAM intensified and advanced northward to the Lunpola Basin by at least ∼25.5 Ma.

The rise and demise of the Paleogene Central Tibetan Valley.

Reconstructing the Paleogene topography and climate of central Tibet informs understanding of collisional tectonic mechanisms and their links to climate and biodiversity. Radiometric dates of volcanic/sedimentary rocks and paleotemperatures based on clumped isotopes within ancient soil carbonate nodules from the Lunpola Basin, part of an east-west trending band of basins in central Tibet and now at 4.7 km, suggest that the basin rose from <2.0 km at 50 to 38 million years (Ma) to >4.0 km by 29 Ma. The height change is quantified using the rates at which wet-bulb temperatures (Tw) decline at land surfaces as those surface rise. In this case, Tw fell from ~8°C at ~38 Ma to ~1°C at 29 Ma, suggesting at least ~2.0 km of surface uplift in ~10 Ma under warm Eocene to Oligocene conditions. These results confirm that a Paleogene Central Tibetan Valley transformed to a plateau before the Neogene.

The organic geochemical characteristics from the Palaeogene lacustrine source rock in the Nyima Basin, Central Tibet, and their geological significance

The Lunpola Basin is a fault‐depression type residual Palaeogene continental basin, and it is the only basin located in Tibet in which industrial oil has been discovered. In recent years, as research has progressed, quantities of oil shale and asphalt were discovered in the adjacent Nyima Basin, which shows a good prospect for exploration. In this study, the organic geochemistry, n‐alkanes, biomarkers, and maturity parameters of the samples were analysed using gas chromatography (GC) and mass spectrometry (MS). The organic geochemistry revealed that the Niubao Formation has a high organic matter abundance (total organic carbon content of 0.15–8.43 wt% and hydrogen index of 31.25–1721.15) and is dominated by type I–II2 kerogen. The GC and MS analyses indicate that the oil shales of the Nyima Basin have a high organic matter abundance and a good hydrocarbon production potential, and the main organic matter sources were aquatic algae and terrestrial plants, as evidenced from the unimodal/bimodal distributions of the n‐alkanes. Besides, the high phytoalkane, gammacerane, homohopane, and gypsiferous mudstone contents in the Nyima Basin indicate a deep, hypoxic, well‐stratified, saline lacustrine sedimentary environment. Under warm climatic conditions, accelerated continental weathering increased nutrient input, leading to water‐mass eutrophication and algal blooms in the water column, while arid conditions and intensified evaporation induced saline stratification, leading to enhanced preservation of organic matter and the formation of high‐quality source rock layers in this lake basin. Therefore, the Eocene global greenhouse effect may have been the main reason for the formation of the large sets of oil shales in the Nyima Basin.

Mid-Miocene Lake Level Fluctuations in the Lunpola Basin, Central Tibetan Plateau

Knowledge of paleolake evolution is highly important for understanding the past hydroclimate regime on the Tibetan Plateau and associated forcing mechanisms. However, the hydrological history of paleolakes on the central plateau, the core region of the plateau, remains largely inconclusive. Here we present new biomarker records from lacustrine deposits of the Lunpori section in the Lunpola Basin to reconstruct detailed lake-level fluctuations during the mid-Miocene. A set of n-alkane indexes, including the proportion of aquatic macrophytes (Paq), average chain length and carbon preference index as well as the content of n-alkanes, vary substantially and consistently throughout the studied interval. Our results altogether show relatively low lake level at ∼16.3–15.5 Ma and high lake level before and after the interval, which is in line with the lithological observations in the section. Further comparison with existing regional and global temperature records suggests that lake level fluctuations can be largely linked to global climatic conditions during the mid-Miocene, with lake expansion during relatively warm periods and vice versa. Therefore, we infer that global climatic changes might have controlled the lake-level fluctuations in this region during the mid-Miocene, whereas the tectonic uplift likely played a subordinate role on this timescale.

The first Fulgoridae (Hemiptera: Fulgoromorpha) from the Eocene of the central Qinghai–Tibetan Plateau

Abstract. The Qinghai–Tibetan Plateau (QTP) played a crucial role in shaping the biodiversity in Asia during the Cenozoic. However, fossil records attributed to insects are still scarce from the QTP, which limits our understanding on the evolution of biodiversity in this large region. Fulgoridae (lanternfly) is a group of large planthopper in body size, which is found primarily in tropical regions. The majority of the Fulgoridae bear brilliant colors and elongated heads. The fossil records of Fulgoridae span from the Eocene to Miocene in the Northern Hemisphere, and only a few fossil species from Neogene deposits have been reported in Asia so far. Here, we report a new fossil record of Fulgoridae from the middle Eocene Lunpola Basin, central QTP. The specimen is in lateral compression, with complete abdomen, thorax, and part of the wings preserved, while most of the head is missing. It belongs to the “lower Fulgoroidea” judging by several strong lateral spines on the hind tibia and a row of teeth at the apex of the second metatarsomere. This fossil specimen is assigned to Fulgoridae by comparison with nine families of the “lower Fulgoroidea”. The specimen represents the earliest Fulgoridae fossil record in Asia and was considered a new morphotaxon based on the peculiar legs and wings. Based on the modern distribution of fulgorid and other paleontological evidence, we suggest a warm climate with relatively low elevation during the middle Eocene in the central QTP. Therefore, this new fossil record not only provides important information on insect diversity in the middle Eocene, but also gives new evidence on the paleoenvironment in the core area of the QTP from the perspective of an insect.

The influence of sedimentary systems and paleo-geomorphology on the physical properties of a reservoir in the Niubao formation, Lunpola basin, central Tibetan Plateau

The influence of sedimentary systems and paleo-geomorphology on the physical properties of a reservoir in the Niubao formation, Lunpola basin, central Tibetan Plateau