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On July 18, 2023, on the K54 + 670 ~ K54 + 700 section of G351 National Highway in Baoxing County, Ya'an City, Sichuan Province, the rock mass (30° 25′ 4.8″ N, 102° 50′ 21.84″ E) located at the entrance of Leying in the Guanyinyan Open-cut Tunnel and affected by Lushan earthquakes and heavy rainfall factors suffered a rock mass collapse accident (hereinafter referred to as the Guanyinyan collapse, or collapse). It is a typical delayed rock mass collapse event that occurs under the influences of historical earthquake sequences and rainy season rainfall. The collapsed area has the maximum thickness close to 2 m, and a volume of about 1500–2000 m3. Some collapsed rocks have rolled into the interior of the tunnel and the riverbed, and boulders with a diameter of nearly 5 m have been found in the river channel. Most of the collapsed material accumulates on the road, approximately 1260 m3, burying some 30 m of the highway, severely affecting the normal use thereof. This article used a detailed field investigation, unmanned aerial vehicle (UAV) photogrammetry, historical image comparison, and numerical simulation methods to gain a deeper understanding of the engineering geology and historical earthquake situation in the study area. A three-dimensional site model was also established to identify the rock mass structural joints and accumulation conditions in the collapsed area, and the deterioration and fracture factors and historical evolution process of the dangerous rock mass were briefly analyzed, Finally, a comparative analysis was conducted between the simulated results using the three-dimensional finite discrete element method (FDEM) and the dynamic process as evinced by of real-time video footage. The collapse mainly experienced a local instability stage, stress adjustment stage, and overall collapse-accumulation stage. The further understanding of its motion characteristics and energy evolution can provide a basis for subsequent protection design and also a valuable experience for similar research in the region. [ABSTRACT FROM AUTHOR]

Geoheritage represents typical geological phenomena formed through internal and external geological processes during the Earth's long evolution. It serves as a carrier of crucial information regarding the Earth's evolution, the origin of life, and changes in the geographic environment. Additionally, it is a valuable geological resource for human utilization. In order to provide essential information for the scientific protection and utilization of geoheritage resources, this paper summarizes and further categorizes the types, grades, and distribution characteristics of geoheritage in China based on extensive firsthand data obtained from recent investigations. The results can be summaried in four aspects: (1) As of the end of 2018, a total of 7,267 important geoheritage sites (including global, national, and provincial levels) have been discovered and surveyed in China. Among them, there are 3,154 geoheritage sites of basic geology, 3,935 geoheritage sites of geomorphic landscape, and 178 geoheritage sites of geological disaster. They can be further categorized into 13 classes and 46 sub-classes, such as stratigraphic sections, rock profiles, rock and soil landforms, and earthquake relics. (2) Through expert evaluations and comparative studies, there are 218 Grade I (global level) geoheritage sites, 1,919 Grade II (national level) geoheritage sites, 4,732 Grade III (provincial level) geoheritage sites, and 398 Grade IV (below provincial level) geoheritage sites in China. (3) Geoheritage in China are mainly distributed in five regions: Southwest China, East China, Central China, Northwest, and North China. The geoheritage sites of basic geology are mainly distributed in the Southwest China, Central China, East China, Northwest China, and North China, with the Southwest China having the highest number, accounting for approximately 27%. The geoheritage sites of geomorphic landscape are mainly distributed in the Southwest China, Northwest China, East China, Central China, and North China, with the Southwest China having the highest number, accounting for approximately 29%. The geoheritage sites of geological disaster are mainly distributed in the Southwest China, Northwest China, and Central China, with the Southwest China having the highest number, accounting for approximately 47%. [ABSTRACT FROM AUTHOR]

Historical geology, climatic oscillations, and seed dispersal capabilities are thought to influence the population dynamics and genetics of plants, especially for distribution-restricted and threatened species. Investigating the genetic resources within and among taxa is a prerequisite for conservation management. The Cycas taiwaniana complex consists of six endangered species that are endemic to South China. In this study, we investigated the relationship between phylogeographic history and the genetic structure of the C. taiwaniana complex. To estimate the phylogeographic history of the complex, we assessed the genetic structure and divergence time, and performed phylogenetic and demographic historical analyses. Two chloroplast DNA intergenic regions (cpDNA), two single-copy nuclear genes (SCNGs), and six microsatellite loci (SSR) were sequenced for 18 populations. The SCNG data indicated a high genetic diversity within populations, a low genetic diversity among populations, and significant genetic differentiation among populations. Significant phylogeographical structure was detected. Structure and phylogenetic analyses both revealed that the 18 populations of the C. taiwaniana complex have two main lineages, which were estimated to diverge in the Middle Pleistocene. We propose that Cycas fairylakea was incorporated into Cycas szechuanensis and that the other populations, which are mainly located on Hainan Island, merged into one lineage. Bayesian skyline plot analyses revealed that the C. taiwaniana complex experienced a recent decline, suggesting that the complex probably experienced a bottleneck event. We infer that the genetic structure of the C. taiwaniana complex has been affected by Pleistocene climate shifts, sea-level oscillations, and human activities. In addition to providing new insights into the evolutionary legacy of the genus, the genetic characterizations will be useful for the conservation of Cycas species. [ABSTRACT FROM AUTHOR]

Abstract: The earlier Late Pleistocene mandibular ramus from Xujiayao (northern China) preserves traits that vary distributionally among western Old World Pleistocene Homo samples and between Early/Middle Pleistocene archaic humans and Late Pleistocene modern humans in eastern Eurasia. Xujiayao 14 presents a lateral mandibular notch crest, an open mandibular foramen, a wide ramus, an asymmetrical mandibular notch, an enlarged superior medial pterygoid tubercle, (probably) a retromolar space, and gonial eversion, as well as an unusual depression in the planum triangulare. The first two traits appear ancestral for Later Pleistocene and recent Homo and are dominant among modern humans. The second two traits largely separate Xujiayao 14 and archaic Homo from modern humans. The next two traits are found in the highest frequency among the Neandertals, although gonial eversion contrasts with Late Pleistocene Neandertals. Xujiayao 14, in the context of Pleistocene and recent Homo samples and the other Xujiayao human remains, therefore provides a morphological mosaic, highlighting regional variation through the Pleistocene. [Copyright &y& Elsevier]

Abstract: Among the 14small mammal species from the early Miocene locality of the northern area of the Junggar basin (northern Xinjiang, China), four species are cricetids (Rodentia): unnamed species of Cricetodon and Eumyarion, and two new species, Karydomys debruijni nov. sp. and Megacricetodon beijiangensis nov. sp. Some aspects of the morphology of Cricetodon sp. are shared by Eucricetodon from the late Oligocene, suggesting that these specimens could be of intermediate form between Eucricetodon and Cricetodon. One tooth of Eumyarion sp. was found, making its determination uncertain, but its morphology is clearly differentiated from the one of Cricetodon sp. The species K. debruijni nov. sp. is established based on its primitive features compared to the species known in Europe and Anatolia, and its specific association of characters compared to Karydomys dzerzhinskii. M. beijiangensis nov. sp. shows many plesiomorphic features compared to the species already described in the middle Miocene of China. Based on both the whole assemblage of rodents and the species of cricetids, the biochronologic position and the age of the locality are discussed. The locality appears to be biochronologically very close to the fauna from the Chul’adyr Formation in Aktau Mountains, but we propose an age slightly older than the one proposed for this fauna, probably equivalent to the MN3 biozone in Europe. [Copyright &y& Elsevier]

Abstract: Until 1950, a few handaxe yielding sites were known in China. Since then, several sites were discovered, as for example Dingcun, Lantian and Bose. However, only after the publication of the discovery of handaxes at Bose in 2000, the theory of Movius, who rejected the evidence of proper handaxes in China, was really questioned. This bad understanding of the prehistory in China, would be bound to a misunderstanding of the geological Quaternary context. This article aims at improving the situation by presenting the stratigraphy of handaxe-yielding sites according to their geographical and environmental context, highly contrasted between north and south. [ABSTRACT FROM AUTHOR]

Abstract: Based on the observational data of 6 storms and 8 different beaches on the coasts of southern China, the paper is concerned with the characteristics of storm-effects on beaches with different morphodynamic types in South China. A dissipative beach is very stable and has a weak response to tropical storms. The storm-induced morphological changes for this type of beach are characterized by erosion at the dune toe and minor changes on the beach face. A low-tide terrace beach has a strong response to storms, with marked changes in the upper profile. A barred beach usually experiences berm erosion, swash bar smoothening, and seaward bar migration during storms. Overwash may occur for the beach without backshore dune or protection. In this paper, backshore changes and the alteration of beach gradient in response to tropical storms are discussed. With taking into account tidal influences, a new morphodynamic parameter (ε T ) is proposed in order to highlight the beach response intensity to storm action. Results show that the inherent morphodynamic properties have significant effects on the beach response to storm. The more dissipative beach has a smaller response intensity and shows a moderate change in beach profile during a storm, while a more reflective beach has a greater response intensity and changes markedly under storm conditions. [ABSTRACT FROM AUTHOR]

The Xianshuihe fault zone (XFZ) forms a boundary that accommodates crustal movement eastwards from central Tibet. The lack of well-defined time constraints has hampered the reconstruction of the geometric and kinematic evolution of the fault zone, and inhibited the development of a consistent regional tectonic model. New geochronological investigations of mica K/Ar and apatite fission-track ages on the Ganzi-Yushu segment of the XFZ indicate that fault activity started ca. 13 Ma before present, which considerably precedes the 5 Ma initiation of offset on the Xiaojiang fault (XjF) segment. Different initiation times for different fault segments clearly demonstrate that the geometric and kinematic evolution of the XFZ can be divided into two periods. The XFZ cut through the Dangjiang, Ganzi, and Gongga Shan areas, and reached the Qinghe-Yanyuan area during an early stage, from ca. 13 to 5 Ma, as a boundary fault with lateral mass transfer from the interior to southeast Tibet. At the southern edge of the XFZ, the movement took advantage of the southern segment of the Longmen Shan thrust fault - the Jinhe-Qinghe thrust fault. During the late stage, from 5 Ma to present, the fault zone passed through the Yushu, Ganzi, and Gongga Shan areas, then offset the Longmen Shan thrust fault belt and reached the Kunming area. The Jinhe-Qinghe fault was abandoned in the later period as the southern part of the XFZ, and the XjF became active because of continuous clockwise rotation of the crust around the eastern syntaxis. [ABSTRACT FROM AUTHOR]

Abstract: 40Ar/39Ar dating studies have been carried out along the Dangjin Pass transect across the Altyn Strike-Slip Fault (ASSF). The samples gave ages of 445.2–454.3Ma in the Northern Belt, 164.3–178.4Ma in the Mesozoic Shear Zone and 26.3–36.4Ma in the Cenozoic Shear Zone. Using the piercing point of the Bashikaogong Fault and the Cangma-Heihe Fault an offset of 350–400km along the ASSF has been estimated. The 40Ar/39Ar dating of the syntectonic-growth or syntectonic-resetting minerals from the samples within the ASSF belt, and offset estimations from different age piercing points suggest that the ASSF should be initiated in the Middle Jurassic (178.4–160Ma). Combined with previously reported ages, our studies show that the ASSF is characterized by multi-phase re-activation during 85–100, 25-40 and 8–10Ma following its initiation in the Middle Jurassic in the regional tectonic setting of convergence between the Indian and Eurasian continents. [Copyright &y& Elsevier]

Abstract: A new plant is described on the basis of compression fossils from the Xichong Formation, Middle Devonian (upper Givetian) of Yunnan Province, China. The plant has a stout stem (up to 90 mm diameter). Lateral sterile branches are ramified in a series of perpendicular dichotomies (proximally close and ‘digitate’), terminating in recurved tips, and lack appendages. Fertile branches are unramified, and have fertile appendages attached in a helical pattern. The fertile appendages are composed of a central axis to which is attached proximally a pair of sporangia, and which distally becomes flattened or broadened with a shallow terminal dissection and two pairs of sporangia attached on each side of the dissection in a fan-like arrangement. Sterile and fertile branching systems are not found in organic connection, but are inferred to belong to the same plant both because of close association and because both sterile branching systems and fertile appendages bear characteristic narrow spines. Although the affinities of this plant are not certain, we assign it to Cladoxylopsida on the basis of the ‘digitate’ branching from which we infer an underlying highly dissected vascular system. However the plant lacks many characteristics of the best defined group of Middle Devonian Cladoxylopsida, Pseudosporochnales, including sterile appendages, straight tips and distinctive sclerid nests within the cortex. After consideration, previous records of Pseudosporochnus in South China are discounted as the digitate branches featured probably represent our new plant. The new plant, named Rhipidophyton acanthum Berry et Wang gen. et sp. nov, further highlights the phytogeographic isolation of the Yunnan Middle Devonian flora, and suggests greater diversity of Middle Devonian cladoxylopsid bauplans than previously recognised. [Copyright &y& Elsevier]

The Jiaodong gold province, the largest gold-producing district in China, is located in the Jiaodong peninsula at the eastern margin of the North China craton and bounded by the continental scale Tan-Lu fault, 40 km to the west. Previous geochronological studies suggest that pervasive gold deposition took place in the westem part of the province between 122 and 119 Ma. Here we report high-quality, 40Ar/39Ar ages of the Pengjiakuang and Rushan deposits from the eastern part of the Jiaodong gold province, placing additional chronological constraints on the timing of regional mineralization. Seven sericite grains extracted from auriferous alteration assemblages at the Pengjiakuang deposit yielded well-defined plateau ages between 120.9 ± 0.4 and 119.1 ± 0.2 Ma (2σ). Three separates of igneous biotite from a sample of the Queshan gneissic granite, adjacent to the Pengjiakuang deposit, gave reproducible plateau ages of 124.6 ± 0.6 to 123.9 ± 0.4 Ma (2σ). Six sericite separates from two samples in the Rushan deposit yielded 40Ar/39Ar plateau ages at 109.3 ± 0.3 to 107.7 ± 0.5 Ma (2σ), whereas biotite from the Kunyushan monzogranite that hosts the Rushan deposit had plateau ages ranging from 129.0 ± 0.6 to 126.9 ± 0.6 Ma (3 separates from one sample). The apparent age gap between hydrothermal sericite and magmtic biotite from both deposits, together with the similar argon closure temperatures for these mica minerals, suggest that gold mineralization had no direct relationship to the granitoid magmatism. Instead, gold deposition coincided with the emplacement of mafic to intermediate dikes widespread in the Jiaodong gold province, which have been dated at ca. 122 to 119 Ma and, less commonly, at 110 to 102 Ma. The new 40Ar/39Ar ages from the eastern Jiaodong peninsula, when combined with published data from the western part suggest that gold mineralization was broadly contemporaneous throughout the district. The Early Cretaceous gold mineralization also is widely developed in four other major gold districts along the Tan-Lu fault. The temporal and spatial correlation of these gold deposits with mafic to intermediate dikes commonly found in most mineralized areas, the presence of well-documented metamorphic core complexes and halfgraben basins along the Tan-Lu fault, and voluminous basalts therein, snggest that the Early Cretaceous was an important period of lithospheric extension, possibly caused by the late Mesozoic lithospheric thinning beneath the eastern block of the North China craton. Lithospheric thinning and extension could have resulted in abnormally high heat and fluid fluxes necessary for large-scaled gold mineralization. [ABSTRACT FROM AUTHOR]

It was less than a decade ago that paleontologists became enthralled with spectacular new fossils from China's western Liaoning Province. Weak laws, they say, have failed to halt the illegal excavation and trade in fossils, and confusing rules governing the work of legitimate scientists are hindering research. Liaoning's Zhao says that the scientists on last year's dig applied to the wrong office and that his office, for fossil administration, would have handled the matter expeditiously. In response, Zhao says that IVPP has been allowed to keep the fossils it excavated and that fossils with major scientific significance should be kept by scientists.