Search Results (429)

Major earthquakes often induce multi-structural rupture styles, which serve as a crucial basis for understanding stress partitioning and strain adjustment within tectonic systems, as well as for constructing regional deformation models. The 1927 M 8.0 Gulang earthquake in the northeastern Tibetan Plateau exemplifies this phenomenon. This rare event, characterized by a single mainshock triggering multiple structural ruptures, resulted in approximately 40,000 casualties and numerous missing persons. In this study, we integrate interpretations of satellite remote sensing imagery, field observations of surface ruptures, and analyses of regional tectonic–geomorphic deformations to reconstruct the coseismic processes of the Gulang earthquake. Our findings reveal that the coseismic surface ruptures exhibit distinct mechanical characteristics driven by complex stress fields. Survey and analysis results indicate that regional tectonic compression oriented from SSW–SW to NNE–NE triggered the mainshock rupture. This stress regime caused nearly E–W folding of strata north of the Huangcheng–Shuangta Fault (HSF), alongside sinistral strike-slip motion in the central-eastern section and thrusting at the eastern end of the Southern Wuwei Basin Fault (SWBF). Blocked by the rigid Alxa Block to the north, comprehensive evidence—including the Late Holocene gravelly clay folded strata formed by north-to-south compression in the Liutiao Lake area, the geomorphic deformation characterized by higher northern and lower southern terraces on both sides of the east–west-trending fault, and the clockwise rotational tectonic surfaces developed at the eastern end of the HSF zone in Shuixiakou—indicates that the coseismic tectonic movement and energy transfer within the meizoseismal area underwent a rapid clockwise rotation from NE to S. This strain rotation induced N–S tensional rupturing along the southern branch of the eastern HSF and nearly E–W thrusting along the NNW-trending Wuwei–Gulang Fault (WGF). Furthermore, this intense and rapid clockwise rotation generated a transient extensional environment characterized by rapid E–W to SE stretching, leading to the formation of a newly identified, NNE-trending, high-angle dextral strike-slip normal fault (hereafter referred to as the NNEF). This process also triggered localized activity at the junctions between the NNEF and the Lenglongling Fault (LLLF), and between the WGF and the nearly E–W-trending Gulang Fault (GLF). We conclude that the seismogenic structure of the 1927 Gulang mainshock comprises three primary components: (1) a fault–fold belt consisting of the SWBF and the nearly E–W fold system north of the HSF; (2) the southern branch of the eastern HSF; and (3) the WGF. The observed segmental activities of the GLF and LLLF are attributed to local strain adjustments. By identifying the newly formed NNEF and characterizing these segmental activations, this study provides new insights into the mechanisms of local strain adjustment within the tectonic systems of the northeastern Tibetan Plateau. Full article

The European Middle Pleistocene represents a critical spatiotemporal interval in human evolution, marked by increasing morphological variability and ongoing debate regarding the evolutionary processes leading to the emergence of Neandertals. In particular, it remains unclear whether this variability reflects the coexistence of multiple evolutionary lineages within Europe or structured variation within a single, evolving lineage. Within this context, the site of Bilzingsleben (Thuringia, Germany) provides a key contribution to discussions of European Middle Pleistocene population structure. This study presents a detailed morphological assessment of the Bilzingsleben E7 mandibular fragment, integrating qualitative anatomical observations with quantitative analyses of discrete characters. The Bilzingsleben mandible was examined directly and evaluated within a broad comparative framework including European Middle Pleistocene hominins, Neandertals, and selected African and Asian specimens. Multivariate analyses, including Principal Coordinates Analysis (PCoA) and neighbor-joining cluster analysis based on Gower distances, were used to explore patterns of morphological affinity. Qualitative analysis indicates that the Bilzingsleben mandible exhibits a mosaic combination of predominantly primitive features—such as multiple mental foramina, marked lateral relief of the corpus, and a weakly developed submandibular fossa—together with a limited number of incipiently derived traits, including posterior extension of the corpus and a downward orientation of the digastric fossae. Quantitative results consistently place Bilzingsleben within the morphological variability of European Middle Pleistocene hominins but outside the compact Neandertal cluster. In the PCoA, Bilzingsleben occupies an intermediate (PCo1) and peripheral position (PCo2), contrasting with more centrally positioned specimens such as Mauer. Taken together, these results support an interpretation of Bilzingsleben as part of a European Middle Pleistocene set of populations exhibiting mosaic morphology, rather than considering Bilzingsleben as evidence for a distinct evolutionary lineage. When integrated with evidence from other anatomical elements from Bilzingsleben, the mandibular morphology supports interpreting this population within the broader evolutionary context of the Neandertal lineage. Full article

This study analyses the funerary practices in hypogea (rock-cut tombs) of the Middle Bronze Age in southern Portugal with the aim of deepening our understanding of Bronze Age funerary rituals in southwestern Iberia. A total of 57 hypogea from seven archaeological sites were examined. The study followed an interdisciplinary approach integrating data from biological anthropology and archaeology, articulating chronology, osteological analysis, funerary architecture, and material culture. The hypogea date to the first half of the 2nd millennium BCE, corresponding to the regional Middle Bronze Age. Of the 95 individuals analysed, 82% were adults; females represented 34% and males 21% of the total sample. The hypogea present several architectural typologies, with entrances oriented towards southeast (30%), northeast (23%), southwest (22%), and northwest (22%), possibly related to moments of the solar cycle. Burials were single (54%), double (17%), or multiple (11%), with 68% primary inhumations and 32% secondary inhumations, reflecting the re-use of funerary spaces. Grave goods, present in 57% of the cases, were more frequent and diversified among women, including ceramic vessels (79%) and metal awls (61%). Like male individuals, women were also associated with weapons, suggesting an elevated social status for both sexes. Full article

Fossils provide invaluable data for evolutionary studies in oceanic islands. The paleontological record of the Macaronesian archipelagos has been the target of many researchers for a long time, with a recent surge in interest in scientific research related to their paleontological heritage. In the Macaronesian Azores archipelago, the marine invertebrate fossil record from the warmest period of the Last Interglacial stage (also known as Marine Isotopic Stage 5e—MIS 5e) represents approximately 95.6% of the total species. In contrast, the MIS 5e marine vertebrate fossil record comprises only four reported species (2.2%), with marine algae accounting for the remaining 2.2% (four species). This study reports on—and adds to the paleobiodiversity of the MIS 5e deposits at Santa Maria Island (Azores Archipelago)—two marine mesopelagic lanternfishes, identified from their otoliths: Diaphus cf. holti Tåning, 1918, and Symbolophorus veranyi (Moreau, 1888). Finally, we offer a plausible explanation for the presence of mesopelagic fishes in the MIS 5e fossiliferous deposits of Santa Maria Island. Full article

Arid Central Asia (ACA) is a major source of atmospheric dust in the Northern Hemisphere; however, the evolutionary models and driving mechanisms of Holocene aeolian activity in this region remain debated. Based on 13 reliable AMS ¹⁴C dates from the Sayram Lake SLM2009 sediment core, this study reconstructs the Holocene sequence in aeolian activity through end-member modeling analysis (EMMA). It evaluates its relationship with regional atmospheric circulation. Four end-members were identified from base to top: EM1, with a modal grain size of 7.58 μm, represents low-energy suspension deposition; EM2 (26.30 μm) reflects lacustrine hydrodynamic processes; while EM3 (52.48 μm) and EM4 (416.86 μm) serve as proxies for regional aeolian activity. The results indicate that aeolian activity was relatively strong during the early Holocene (reaching peaks at 11.7–11.2 and 9.2–8.1 cal ka BP), significantly intensified during the mid-Holocene (7.3–5.3 cal ka BP), and gradually weakened in the late Holocene (since 4.0 cal ka BP). Comparison of the aeolian record from Lake Sayram with Greenland ice cores, North Atlantic ice-rafted debris events, and the GISP2 K⁺ record indicates that variations in aeolian activity in arid Central Asia are closely linked to the Northern Hemisphere climate system. We propose that these variations were primarily modulated by large-scale atmospheric circulation, driven by the synergistic interaction between the Siberian High and the mid-latitude westerlies. Full article

The main objective of the present study is to reveal the palette of pigments and the other specific constituent materials as well as the techniques used by the Roman artists to create the mural paintings discovered in the ancient city of Tomis, the modern-day Constanţa, Romania’s largest seaport and a major tourist hub on the Black Sea. This paper is an archeometric study based on the physical, chemical and biological analyses of the archeological Roman mural painting fragments from the ancient city of Tomis dating from the 5th to 6th century A.D. and to our knowledge is among the very few research studies carried out so far on the ancient Roman wall painting discovered in Romania. The methods of scientific investigation employed directly on the archeological fragments, on samples taken from the fragments and on the cross-sections prepared from the samples were: optical microscopy (OM), digital microscopy, X-ray fluorescence spectrometry (XRF) and attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR). Examination and analysis of the archeological mural fragments revealed that the painted fragments consist of ground support and successive layers of color displaying specific characteristics of the artistic technique, such as imitation of marble cladding or meticulous smoothing of the surface to achieve a glossy and compact finish. It was also found that fragments exhibit subtle variations in different colors, identified in general terms, showing seven color tones: cinnabar red, red-violet, red ochre, yellow ochre, white, gray-blue, gray-black and black. The physical–chemical and biological analyses carried out provide the diagnosis and theoretical basis for choosing an appropriate conservation methodology and the correct restoration treatment of the discovered mural painting, with a view to its museum display through exhibition and virtual reconstruction and scientific use by the setting up of a useful database for researchers or specialists in museums on Roman archeology and art. Full article

Modern pollen rain studies provide essential calibration for interpreting fossil pollen records, particularly in montane environments. This study explores pollen–vegetation relationships along an altitudinal transect in the Rarău Massif (Eastern Carpathians, Romania). Eight moss cushion samples collected between 1215 and 1619 m a.s.l. were analysed palynologically and compared with eight paired vegetation surveys. Multivariate analyses, including hierarchical clustering, Mantel tests, NMDS, and Procrustes analysis, were applied to evaluate floristic and palynological similarity in relation to altitude. Pollen spectra are dominated by Picea, reflecting the prevalence of spruce forests characteristic of the montane belt, while Abies and Pinus occur in lower proportions, indicating a secondary role. Broad-leaved taxa such as Fagus, Betula, and Alnus complement the arboreal pollen signal, whereas thermophilous taxa Quercus and Tilia represent extra-local pollen input from lower altitudes. Herbaceous and shrub taxa are generally underrepresented in the pollen record relative to field observations. Pollen taxa associated with anthropogenic disturbance (Plantago, Rumex, Artemisia and Urtica) show a constant presence, which may suggest localized human influence likely linked to grazing and tourism. Statistical results show weak and non-significant correlations between pollen composition, vegetation structure, and altitude. Overall, modern pollen rain reflects the dominant vegetation structure of the studied montane belt but shows limited fidelity at the local floristic scale. Full article

Alluvial plains in the marginal zone of the monsoon system are sensitive to the climate–hydrology interaction. However, long term, high-resolution sedimentary records remain scarce in the Songnen Plain of Northeast China. This limited our understanding of the paleoclimate–paleohydrology coupling evolution over glacial–interglacial cycles. A 50.6 m continuous core was retrieved from the western Songnen Plain. The age–depth model and wavelet transform spectrum showed sedimentary continuity from ~885 ka B.P. (the late Early Pleistocene) to ~6 ka B.P. (the early Holocene), with no major hiatuses exceeding orbital resolution. Grain size analyses revealed 18 microfacies, which were synthesized into two major evolutionary cycles: a fan-delta front cycle (dominated by subaqueous mouth bars and distributary channels) and a fan-delta plain cycle (characterized by intertributary bays, floodplain lakes/swamps, and crevasse splays). The absence of pro-delta facies and the sediment succession record the oscillatory shrinkage of the Songnen paleolake. The pulsed enhancements of hydrodynamic energy, marked by grain size coarsening, coincide with major glacial–interglacial transitions (MIS 20/19, 18/17, 16/15, 14/13, 8/7, 6/5, 4/3, and 2/1), whereas fining grain sizes dominate warm interglacial periods (MIS 11, 9, 7, 5, 3, 1). These patterns are sensitive response of the alluvial plain to orbital-scale climate change. Cold–arid glacial background promoted vegetation loss and hydrological instability, and warm–humid interglacial background favored low-energy hydrological condition. This study demonstrates that the regional alluvial evolution was primarily controlled by global ice-volume fluctuations through variability of the East Asian summer monsoon. This study provides a reference for the muti-scale climate–hydrology coupling mechanism study in the northern marginal zone of EASM and highlights the importance of alluvial sediment succession in paleo-research. Full article

Dental wear provides valuable evidence for reconstructing past human behaviour, including diet abrasiveness and non-masticatory activities such as the use of teeth as a “third hand”. This study investigates activity-induced dental modifications (AIDMs) in two adult human skeletons recovered from a 15th–19th-century necropolis at the St. Athanasius Church in Niculițel (Tulcea County, Romania). Dental remains and associated dental calculus were examined using low- and high-magnification optical microscopy and scanning electron microscopy (SEM). Well-polished grooves with parallel striations were identified on the incisor crowns, consistent with repetitive extra-masticatory activities related to fibre drafting during spinning and textile production. Dental calculus analysis revealed the presence of plant and animal fibres, providing direct micro-contextual evidence for textile-related practices. These results offer new insights into the use of teeth as tools and contribute to the reconstruction of textile-related craft activities during the Ottoman and early modern periods in southeastern Europe. Full article

Shell middens of Guyana’s northwestern coast are a tangible stratified archive of prehistoric occupation and land use during the Holocene, an era of increased human impacts on the landscape. This study integrates stable isotope and zooarchaeological evidence to understand prehistoric land use, shell midden function, and the complex relationship between archaic populations and their landscape. We synthesize recently excavated data and archival museum collection for seven sites dating between 7500 and 2000 BP including stable isotope results of 37 individuals. Zooarchaeological materials are pooled to provide long-term patterns of human predation during the Holocene while reducing site-specific noise. This we believe highlights patterns of prey selection and exploitation intensity. We conclude that climate fluctuations during the mid Holocene influenced fishing intensification and subsequently a shift in human predation, which affected small to medium-sized fauna, estuary productivity and changes in vegetation patterns including mangrove expansion. These changes were shaped by landscape manipulation and influenced by shoreline movement and population mobility and seasonal resource use. Altogether, these processes left enduring ecological legacies along the northwestern coast of Guyana. Full article

This study presents new phytolith data that reconstruct the vegetation patterns and environmental context of medieval sites in northeastern Romania, integrated with previously published archaeozoological evidence. Sediment samples from cultural layers at Târgu Neamț–La Damian and Neamț Fortress were analysed following standard extraction protocols and classified according to the International Code for Phytolith Nomenclature (ICPN 2.0). The newly obtained phytolith assemblages are dominated by morphotypes from the Poaceae family, with diagnostic cereal forms, indicating intensive cereal use. The presence of arboreal and non-grass phytoliths further suggests a mosaic landscape combining grass-dominated open areas, pastures, and nearby woodland. When compared with existing faunal data, characterized by a predominance of domestic species such as cattle, sheep/goat, and pig, the results support the reconstruction of a diversified agro-pastoral economy adapted to local geomorphological and climatic conditions. The integration of new phytolith and existing archaeozoological data highlights the complementary role of plant microremains in reconstructing medieval environments, providing valuable insight into agro-pastoral resources, vegetation dynamics, and human–landscape interactions in the eastern Carpathian region. This approach enhances our understanding of the ecological basis of medieval Moldavian communities and contributes to the reconstruction of Late Holocene anthropogenic landscape dynamics within a Quaternary environmental framework. Full article

Alluvial–proluvial parent-material soils are widely distributed in the Qinghai Lake Basin; however, their timing of development and associated climatic background remain poorly constrained. In this study, two representative alluvial–proluvial fan-covered soil profiles (QRZQ and YXC) from the Qinghai Lake Basin were investigated. Quartz optically stimulated luminescence (OSL) dating was combined with analyses of grain-size composition and soil organic carbon (SOC) to constrain the timing of soil development and its climatic background. The results show that the studied soil profiles are mainly characterized by Ah–As–C and Ah–A–C horizon configurations, with soil development spanning from 15.7 to 1.0 ka. The underlying alluvial–proluvial parent material of the QRZQ profile formed during the Last deglaciation, whereas the oldest OSL ages in the YXC profile occur within a weakly developed A horizon, indicating that this profile had already transitioned from a depositional environment to a pedogenic environment during the Last deglaciation. This contrast reflects staged differences between depositional and pedogenic processes within alluvial–proluvial settings. The soils were formed through upbuilding pedogenesis, in which sediment accumulation and top-down pedogenic modification proceeded concurrently. Grain-size composition and SOC characteristics further indicate that the depositional environment of the YXC profile was relatively stable. Integrating the obtained chronological results with regional climatic changes suggests that climate variability in the Qinghai Lake Basin exerted a primary control on the transformation between sedimentary processes and soil development. In particular, the Late Holocene (0–4 ka), characterized by a generally cold–dry climate accompanied by pronounced humidity fluctuations, represents an important pedogenic stage for alluvial–proluvial parent-material soils in the Qinghai Lake Basin. This study provides a robust chronological framework for further investigating the mechanisms of soil development in alluvial–proluvial environments from a climatic perspective. Full article

Compound geological disaster chains pose major challenges for disaster prevention in mountainous regions due to their complex mechanisms and cascading impacts. This study investigates a landslide–debris flow–flash flood hazard chain that occurred on 21 July 2024 in the Xujia River catchment, Mianning County, Sichuan Province, China. This event is used as a representative case to improve the understanding of the formation and amplification mechanisms of breach-type debris flows through dynamic inversion constrained by sedimentary records. The objective is to reconstruct the evolution of the event and assess its downstream hazard extent. Post-disaster sedimentary and geomorphological records, including deposit distribution, channel aggradation, and flow traces, were systematically analyzed based on remote sensing interpretation, unmanned aerial vehicle surveys, and detailed field investigations. These sedimentary data were used as key constraints to estimate debris flow magnitude and mobility under different rainfall scenarios. A rainfall flood scenario-based estimation method was applied to quantify debris flow magnitude, and numerical simulations were conducted using the Rapid Mass Movement Simulation model to reproduce debris flow propagation and deposition processes. The results indicate that prolonged antecedent rainfall triggered slope failure in a tributary, leading to the accumulation of landslide-derived material and the formation of a temporary channel blockage. The subsequent breach of this blockage significantly amplified debris flow discharge, velocity, and sediment outflow, resulting in downstream hazard expansion. Simulation results constrained by sedimentary evidence show that peak discharge and solid material output under breach conditions were approximately three times higher than those of rainfall-driven scenarios under comparable rainfall frequencies. These findings demonstrate that sedimentary records provide critical constraints for the inversion of landslide debris flow disaster chain dynamics and highlight the effectiveness of post-disaster evidence based numerical assessment for hazard analysis and risk mitigation in debris flow-prone mountainous catchments. Full article

A group of avian species, mostly small passerines, allows us to reconstruct the landscape and general climate of an area of Fuerteventura prior to the arrival of the first humans. Many of the bird species are typical of forest environments and the edges of bodies of water, conditions incompatible with the current hot and arid climate. The record of a high number of quail as well as small flying passerines surely implies the concurrence of two types of diurnal birds of prey, hunters on the ground and in flight, respectively. No trace of the abundant Puffinus holeae has been found, which evidently occupied a habitat very different from those in the north and interior of the island. Full article