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The Baiyinnuoer Pb–Zn deposit, estimated at 26.57 million metric tonnes (Mt) with grades of 1.77% Pb and 5.21% Zn, is situated in the southern Great Xing'an Range (SGXR) of northeast China. The deposit comprises southern and northern ore belts. The southern belt primarily contains skarn ore bodies (32% of reserves) associated with Triassic granodiorite, while the northern belt is dominated by skarn ore bodies (30% of reserves) related to Triassic diorite porphyry. In addition to Triassic skarn‐type mineralization, the deposit also exhibits Early Cretaceous mineralization. This includes vein‐type occurrences (36% of reserves) within volcanic tuff and syenite porphyry, alongside a small amount of skarn ore bodies (2% of reserves) related to syenite porphyry. LA‐ICP‐MS U–Pb dating of intrusive rocks and garnets was conducted to investigate the timing and genesis of these mineralization events, revealing two distinct stages of skarn‐type mineralization. The first stage, associated with Early Triassic granitoids, dates to 254.6 ± 1.4–241.7 ± 2.7 Ma, while the second stage is closely associated with Early Cretaceous syenite porphyry, constrained to 135.4 ± 1.1–135.2 ± 1.6 Ma. Garnet U–Pb dating in the syenite porphyry‐related skarn yielded an age of 134.9 ± 4.7 Ma; however, due to low U content, reliable dating of garnets associated with Early Triassic granitoid‐related skarn was not feasible. Micro‐thermometry and Laser Raman analyses of fluid inclusions within vein‐type ore bodies highlighted distinct differences between vein‐type mineralization and Early Triassic skarn‐type mineralization. Additionally, in situ sulfur isotope analyses of sphalerite from both Early Triassic and Early Cretaceous ore bodies indicate a magmatic origin for sulfur in both stages. Through comprehensive geological, geochronological, in situ sulfur isotope and fluid inclusion studies, the Baiyinnuoer Pb–Zn deposit is conclusively identified as a large deposit characterized by two distinct periods of mineralization (Early Triassic and Early Cretaceous), akin to several other significant polymetallic deposits in NE China. [ABSTRACT FROM AUTHOR]

Whether the Yangtze Block was involved in the global late Mesoproterozoic orogeny remains contentious. The Mesoproterozoic Huodiya Group exposed in the Hannan‐Micangshan Massif on the northwestern margin of the Yangtze Block could provide sufficient evidence to further clarify the regional tectonic affinity. However, quantitative insights into the depositional age, provenance and basin tectonic setting of the Huodiya Group still lack comprehensively constraining. This study presents a combined analysis of zircon U–Pb dating for meta‐sedimentary rocks of the Shangliang Formation of the upper Huodiya Group and intruded gabbroic dykes. Intergraded dating results constrain the late Mesoproterozoic maximum depositional age at ca. 1050 Ma. Ca. 900 Ma formation age for the intruded gabbroic dyke, plus the minimum formation age of the overlying Xixiang Group at ca. 950 Ma, further suggests its deposition should be prior to ca. 950–900 Ma. Concordant detrital zircon ages define pronounced age clusters of ca. 2229–1741 and 2950–2388 Ma and few age populations of ca. 3232–3082 and 1069–1033 Ma, consistent with the tectonothermal events in proximal domains at the northwestern and northern Yangtze Block. Detrital zircon age distribution patterns and cumulative curves, coupled with the stable carbonate platform and shallow‐marine facies sedimentation, suggest a passive continental margin setting for the Huodiya Group on the Yangtze Block margin at the late Mesoproterozoic. Comparative insights into the contemporaneous passive continental margin from north to southwest argue against the existence of a late Mesoproterozoic orogeny along the exterior periphery of the Yangtze Block. [ABSTRACT FROM AUTHOR]

Abundant mafic-felsic intrusions distributed in the Altyn Orogen record orogenic histories related to Proto-Tethys and Paleo-Tethys evolution. Zircon U-Pb dating of the intrusive rocks in the eastern Altyn Orogen identifies at least three major tectono-magmatic episodes, yielding ages of ∼426, ∼376–373 and ∼269–254 Ma. The first two emplacement episodes correspond to the post-collisional magmatism in the Altyn Orogen. The ∼426 Ma granitoids possess adakitic characteristics coupled with enriched isotopes, suggesting that they originated from partial melting of thickened lower continental crust induced by upwelling asthenospheric mantle after slab break-off of the South Altyn Ocean Plate. Next, the ∼376–373 Ma mafic-intermediate rocks and coeval granitoids represent a large thermal event that involved mantle melting with induced new juvenile lower continental crust melting in a post-collisional extensional setting. Finally, the ∼254 Ma diabase dykes intruded into the ∼269 Ma granitoids, which were related to the widespread Late Paleozoic magmatism resulting from Paleo-Tethys Ocean subduction. Post-collisional magmatism in the Altyn Orogen significantly enhances understanding of the tectono-magmatic evolution in the northern Tibetan Plateau. The penetrative influence of Paleo-Tethys Ocean subduction was more extensive than previously thought. [ABSTRACT FROM AUTHOR]

The formation of rodingites has been a continually controversial topic, largely due to the absence of minerals that can be unambiguously dated. Here, we present a case study that utilized LA‐ICPMS garnet U–Pb dating, in conjunction with field investigations, petrology and Raman spectroscopy, to reveal the age and petrogenesis of rodingite in the northern North China Craton. The rodingites are spatially associated with mafic and alkaline rocks. Our findings indicate that rodingitization occurred at ca. 388 Ma, making it about 5–10 Myr younger than its mafic protoliths, but contemporaneous with the adjoining alkaline plutons. These observations suggest that the rodingitization may be attributed to hydrothermal fluids from the alkaline magmas. Our study emphasizes the importance of utilizing garnet U–Pb dating to determine the timing of rodingitization and introduces a novel perspective on the relationship between rodingitization and alkaline magmas in extensional continental settings. [ABSTRACT FROM AUTHOR]

To date, the most complete paleolake‐level reconstructions for the late Pleistocene water bodies that once occupied the Dead Sea depression have been based on the combination of dating of lake sediments and terrestrial materials. However, despite these major accomplishments, there is still limited spatial control regarding the water levels, suggesting some degree of uncertainty concerning the magnitude and rate of lake‐level changes. Here, we re‐examine the late Pleistocene lake‐level changes in the Dead Sea during the transition from paleolake Lisan to the present‐day Dead Sea. We rely on systematic dating of fossil stromatolites including 84 radiocarbon and 15 U‐series ages, stable‐isotope measurements, paleobiology, high‐resolution topography, and numerical modeling to assess lake‐level changes. Our results indicate that the highstand of paleolake Lisan was of shorter duration and the transition between Lake Lisan and the Dead Sea occurred at least 5 Kyrs earlier than previously indicated. By refining the timeline and accuracy of lake‐level positions during the transition paleolake Lisan—Dead Sea, our study offers new insights into the regional and local paleo‐climatic conditions during the last glacial period in this region. Plain Language Summary: Index points, reflecting the unique position of the water levels in space and time, have been broadly used in marine realms to reconstruct past sea‐level changes. Here we study lake‐level variations using index points based on geomorphic and biological markers collected along the western and eastern coasts of the Dead Sea. Previous studies indicate that during the last glacial period (20–30 ka), the Dead Sea depression was filled by paleolake Lisan, which lasted 10 Kyrs. As it dried, dozens of paleo‐shorelines remained etched in the landscape. Lake level index points estimated from 99 radiometric ages in these paleo‐shorelines suggest that Lisan's highstand was shorter and the transition to the Dead Sea occurred 5 Kyrs earlier than previously thought. These novel results suggest an initial and wet period followed by drier conditions, altering the regional paleo‐climatic narrative during the last glacial period. Key Points: Lake paleo‐shorelines and fossil stromatolites are used to reconstruct lake‐level changes during the transition paleolake Lisan‐Dead SeaFossil stromatolites were dated using radiocarbon and U‐series applying temporal and vertical correctionsThe transition between paleolake Lisan and the Dead Sea occurred ∼5 Kyrs earlier than estimated by previous reconstructions [ABSTRACT FROM AUTHOR]

Until the late 20th century, the idea of identifying wildfires in deep time was not generally accepted. One of the basic problems was the fact that charcoal-like wood fragments, so often found in sedimentary rocks and in coals, were termed fusain and, in addition, many researchers could not envision wildfires in peat-forming systems. The advent of Scanning Electron Microscopy and studies on modern charcoals and fossil fusains demonstrated beyond doubt that wildfire residues may be recognized in rocks dating back to at least 350 million years. Increasing numbers of studies on modern and fossil charcoal assemblages from the 1970s through the 1990s established the potential importance of wildfires in the fossil record, using Carboniferous examples in particular. Since the 1990s, extensive progress has been made in understanding modern wildfires and their byproducts. New techniques to study ancient charcoals have allowed considerable progress to be made to integrate modern and ancient fire studies, both before and after the evolution of mankind. Four important developments have made a reassessment of Carboniferous wildfires necessary: the recognition of the role of atmospheric oxygen in controlling the occurrence of wildfire; the development of new microscopical techniques allowing more detailed anatomical data to be obtained from charcoal; the integration of molecular studies with the evolution of fire traits; and new developments in or understanding of post-fire erosion/deposition systems. [ABSTRACT FROM AUTHOR]

The paper reports the first comprehensive physicochemical study of minerals of the amblygonite LiAlPO4F–montebrasite LiAlPO4(OH) series. An EPR spectroscopic and calorimetric study of montebrasite LiAlPO4(OH)0.9F0.1 from the Shuk-Byul rare-metal granite pegmatites (Sangilen Highlands, Tuva) and amblygonite LiAlPO4F0.5(OH)0.5 from pegmatites of the Voron'i Tundras (Kola Peninsula) was carried out. Using the EPR method, the radiation-sensitive paramagnetic O– centers were discovered. They were formed without participation of impurity elements in the regular sites of crystal lattice. The possibility use of minerals of the amblygonite–montebrasite series for EPR geochronometry has been demonstrated for the first time. Using the method of high-temperature melt dissolution calorimetry on a Tian-Calvét microcalorimeter, the enthalpies of formation from elements (298.15 K) = –2326.3 ± 2.2 kJ/mol for montebrasite with the composition LiAl(PO4)(OH)0.9F0.1 and for amblygonite with the composition LiAl(PO4)F0.5(OH)0.5 (‒2347.9 ± 3.1 kJ/mol) are obtained; and the values of this parameter are calculated for the end members with an ideal composition of the series: for montebrasite (–2315.5 ± 2.2 kJ/mol) and for amblygonite (–2401.6 ± 3.1 kJ/mol). The values of the standard entropy S0 (298.15 K) and the Gibbs energy of formation (298.15 K) for intermediate and end members of the amblygonite–montebrasite series are estimated. [ABSTRACT FROM AUTHOR]

To address the limitations of current dating methods, it is crucial to not only enhance existing techniques like U–Pb zircon dating but also explore alternative tools. This study focuses on three common mineral phases—zircon, apatite, and titanite—in an I-type granite. The goal is to assess their reliability as dating tools and propose improved methods for dating granitic rocks. In the case study of the Mt Stirling pluton within the Mt Buller igneous suite in Southeastern Australia, significant variability in laser ablation U–Pb zircon ages (around 100 million years) was observed. To improve the reliability of zircon age data and reduce non-magmatic-related variabilities, a data filtering protocol is applied. This protocol involves several steps such as trimming zircons with excessive K and Ca, excluding zircons with unusual core–rim age relationships, removing zircons with excessive non-formula elements (Al, Fe, and Mn), identifying hydrothermally altered zircons, and applying a 10% discordance threshold. The filtered Concordia Age (406 ± 1 Ma; mean square weighted deviation (MSWD) = 0.7, n = 80) of the host rock exhibits improved precision and reduced error compared to the unfiltered data (399 ± 2 Ma; MSWD = 9.3, n = 240). The filtered individual dates show less scatter and a mean that is different (i.e. outside statistical uncertainty), noting that their total still spans a considerable time range of ~50 million years, exceeding the individual zircon analytical reproducibility of 2 standard errors (~15 million years of 2 SE). Caution is advised when using the proposed error for the pooled analyses as a definitive precision. Similarly, trace element filtering approaches were applied to apatite and titanite samples from Mt Stirling, two phases that arguably cannot be inherited. For apatite, monitoring Ca and P as well as Zr/Y and Th/U ratios, along with identifying age groupings based on Sr concentrations, was effective in eliminating outliers and enhancing dating precision. In the case of titanite, monitoring Ca and Ti, Sr/Zr and Sr/Th ratios, and Sr/Ca and Zr/Ti ratios successfully enhanced dating precision. Notably, apatite and titanite grains were grouped in distinct Sr concentrations (high-, mid-, and low-Sr), with these groups corresponding to different date groups: high-Sr apatite and high- and low-Sr titanite returned c. 403 Ma, while low-Sr apatite and mid-Sr titanite returned c. 420 and 393 Ma, respectively. The spuriously younger or older dates may indicate an open system and influences from various common-Pb sources. The 403 Ma date coincides with the filtered zircon data, placing further confidence in the coupled approach, and is interpreted here as the igneous intrusion age. Notable is that this age is 25 Myr older than previously reported K–Ar age data, thus far considered to be the age of the intrusion. This study underscores the potential for erroneous zircon dates due to cryptic chemical influences. To enhance the reliability of age interpretation using laser ablation analyses, employing a petrochronological approach using split-stream combined age and trace element data is recommended in addition to the combination of multiple geochronometers. In the case of Mt Buller, it has proven crucial to carefully verify chemical closure of all applied geochronometers by monitoring concomitant trace element concentrations. Applied to other intrusions, petrochronology can play a critical role in obtaining reliable age information, even for igneous rocks that appear pristine. With this, we emphasise the importance of a careful approach towards individual age data interpretation, which can be produced fast and in abundance with modern analytical approaches. [ABSTRACT FROM AUTHOR]

Fossils are valuable indicators of the evolutionary history of the clades to which they belong to, especially when they are incorporated as terminal taxa in a total‐evidence phylogeny. According to their state of preservation, fossils are often incompletely described for key morphological characters, such as genitalic structures. Here, the internal parts of the genitalia of a male fossil cricket from Cretaceous amber, †Picogryllus carentonensis Josse & Desutter‐Grandcolas (Oecanthidae, Podoscirtinae), together with other key morphological characters (i.e., metanotal structures and tibial spurs), were reconstructed for the first time by 3D microtomography. Total‐evidence phylogeny and dating combining morphological data (fossils and extant taxa), molecular data (extant taxa only) and time calibration (fossil dates) were performed to evaluate the tempo and mode of evolution of the cricket family Oecanthidae. Divergence time estimates were thus refined and the patterns of transformation for key morphological structures contrasted through the analysis of phylogenetic morphological partitions. Our results show that Oecanthidae date back to the Upper Jurassic (Oxfordian, around 162 Ma) and attest to the presence of the Podoscirtinae in Western Europe during the Lower Cretaceous. Morphological evolution may have been driven by the conquest of new resources (as shown by leg evolution in ancestral Oecanthidae) and/or the 'conquest of silence' (as shown by repetitive and definitive losses of acoustic structures). By contrast, genitalia evolution proved more diffuse. [ABSTRACT FROM AUTHOR]

The geochronological, geochemical, and Sr–Nd isotopic features of the Late Mesozoic volcanic rocks associated with the development of the Nercha Depression in the Eastern Transbaikalia are presented. The structure of the depression involves the sequences of K-rich subalkaline volcanic rocks with content of 55 to 73 wt % SiO2.40Ar/39Ar isotope dating of bulk rock samples was conducted. 40Ar/39Ar dating gives a value of 150.8 ± 1.8 Ma for K-rich andesibasalt and 131.0 ± 1.6 Ma for latite. Volcanic rocks are characterized by depletion of hydrophobic Ti, Nb, and Ta, slightly negative εNd(T) values, but increased in εSr(T) values, which probably indicates contamination processes of primary melts by the crust component. In terms of their geological and geochemical characteristics, the volcanic rocks of the Nercha Depression belong to the shoshonite–latite series of the rear part of the Greater Khingan volcanic region, which formed in the subduction setting of the continental active margin. [ABSTRACT FROM AUTHOR]

Bolt's Farm is the name given to a series of non-hominin bearing fossil sites that have often been suggested to be some of the oldest Pliocene sites in the Cradle of Humankind, South Africa. This article reports the results of the first combined Uranium-Series and Electron Spin Resonance (US-ESR) dating of bovid teeth at Milo's Cave and Aves Cave at Bolt's Farm. Both tooth enamel fragments and tooth enamel powder ages were presented for comparison. US-ESR, EU and LU models are calculated. Overall, the powder ages are consistent with previous uranium-lead and palaeomagnetic age estimates for the Aves Cave deposit, which suggest an age between ~3.15 and 2.61 Ma and provide the first ages for Milo's Cave dates to between ~3.1 and 2.7 Ma. The final ages were not overly dependent on the models used (US-ESR, LU or EU), which all overlap within error. These ages are all consistent with the biochronological age estimate (<3.4–>2.6 Ma) based on the occurrence of Stage I Metridiochoerus andrewsi. Preliminary palaeomagnetic analysis from Milo's Cave indicates a reversal takes place at the site with predominantly intermediate directions, suggesting the deposit may date to the period between ~3.03 and 3.11 Ma within error of the ESR ages. This further suggests that there are no definitive examples of palaeocave deposits at Bolt's Farm older than 3.2 Ma. This research indicates that US-ESR dating has the potential to date fossil sites in the Cradle of Humankind to over 3 Ma. However, bulk sample analysis for US-ESR dating is recommended for sites over 3 Ma. [ABSTRACT FROM AUTHOR]

Dating of igneous rocks from paleo-island arc complexes of orogenic belts makes it possible to determine the precise timing of subduction processes that occurred during the formation of the orogen. Within the central (East Transbaikal) part of the Mongol–Okhotsk orogenic belt, the Kamenka island-arc terrane is an example of such a complex. Its intrusive part is included into the Bereya complex, represented by a gabbro-diorite-tonalite-plagiogranite series of rocks demonstrating subduction geochemical characteristics. The dating of zircons from acidic rocks of this complex by the U–Pb classical method showed that they were formed in a narrow time interval of 203 ± 1–205 ± 1 Ma, which corresponds to the Norian–Rhaetian boundary of the Late Triassic. Taking into account the previously obtained age of the diorites (254 ± 5 Ma), the timing of formation of the entire series of the intrusive rocks is about 50 Ma, thus indicating the probable subduction along the northern (in modern coordinates) margin of the Mongol–Okhotsk Paleocean under the Siberian paleocontinent in the Late Permian – Late Triassic. The diorites of the first phase have positive values of εND(254 Ma) = 3.2–3.6 (TNd(DM) = 879–994 Ma), and the plagiogranites have ɛND(205 Ma) = 2.3–3.5 (TNd(DM) = 859–1028 Ma), which points to the relationship between these rocks and the substance of the depleted mantle source and is consistent with the Sm–Nd isotope characteristics of the juvenile crust of the Central Asian orogenic belt. [ABSTRACT FROM AUTHOR]

Shallow-water carbonate rocks constitute a crucial component of large guyots, arising in distinct environments and harboring valuable insights into the evolutionary stages of seamount islands as well as the tectonic conditions of the underlying oceanic plate. Laser Ablation Multi-Collector Inductively Coupled Plasma Mass Spectrometry (LA-MC-ICP-MS) was used to conduct in situ U–Pb isotope dating of carbonate minerals with low uranium content collected from Weijia Guyot. This dating approach yielded crucial evidence for the vertical development of the seamount. Our study indicates that shallow-water carbonate rocks in Weijia Guyot had a temporal range between 91 My and 137 My. The carbonate rocks underwent two growth phases, Hauterivian to Barremian and Cenomanian to Turonian, with a hiatus of approximately 20 My. Since the Hauterivian age, the shield volcano of Weijia Guyot is essentially complete, with its seamount top exposed at or near sea level and receiving its first stage of shallow-water carbonate sedimentation. Based on the dating of both shallow-water carbonate rocks and hawaiite within the Weijia Guyot, it is inferred that approximately 10 My elapsed from shield-building volcanism to late alkalic volcanism. During the Turonian age, the main reason for the second phase of shallow-water carbonate rocks in the seamounts was the regional tectonic uplift triggered by the drift of the Weijia Guyot along with the Pacific Plate toward the Society hotspot. [ABSTRACT FROM AUTHOR]

High-pressure and ultra-high-pressure metamorphic terrains display an internal architecture consisting of a pile (or stack) of several coherent tectonic thrust sheets or units. Their identification is fundamental for understanding the scale and mechanisms active during subduction and exhumation of these crustal slices. This study investigates the geometry of the northern Dora-Maira Massif and the kinematics of the major tectonic boundaries, combining field and geochronological data. The tectonic stack of the northern Dora-Maira Massif comprises the following units. The lowermost unit (the Pinerolo Unit) is mainly characterized by Upper Carboniferous fluvio-lacustrine (meta-)sediments. The Pinerolo unit is overthrust by a pre-Carboniferous basement. The latter is subdivided in two tectonic units (the Chasteiran and Muret Units) with different Alpine metamorphism (ultra-high-pressure and high-pressure, respectively). The pre-Carboniferous basement of the Muret Unit is thicker than previously thought for two main reasons. Firstly, some paragneisses, traditionally assumed to be Carboniferous and/or Permian in age, display detrital zircon ages indicating a main source at about 600 Ma. Secondly, three samples of the Granero Orthogneiss, previously assumed to be a Permian intrusive body, have provided zircon U–Pb ages of 447 ± 1 Ma, 456 ± 2 Ma and 440 ± 2 Ma, indicating a late Ordovician or early Silurian age for the protoliths. The uppermost unit (the Serre Unit) comprises porphyritic (meta-) volcanic and volcaniclastic rocks dated to the Permian (271 ± 2 Ma), on top of which remnants of the Mesozoic cover is preserved. Detailed mapping of an area about 140 km2 shows that (i) the ultra-high pressure Chasteiran Unit is localized at the boundary between the Pinerolo and Muret Units, (ii) the Granero Orthogneiss may be considered as the mylonitic sole of the Muret Unit, characterized by a top-to-W sense of shear, and (iii) the contact between the Muret and Serre Units displays ductile-to brittle structures (La Fracho Shear Zone), indicating a top-to-the-NW displacement of the hangingwall with respect to the footwall. A final episode of brittle faulting, cutting across the nappe stack (the Trossieri Fault), indicates an extensional stage in the core of the Alpine belt, as previously documented in more external zones. This work provides a necessary and robust basis before an accurate discussion of processes acting during continental subduction of the Dora-Maira Massif may be understood. [ABSTRACT FROM AUTHOR]

In recent decades, East Borneo has become an increasingly important archaeological "hot-spot" in Island Southeast Asia as a result of early dates for rock art ca. 38,000 BP and the greater number of excavated sites that support a much longer period of human occupation. However, the chronology of settlement and adaptation to environmental changes during the Pleistocene–Holocene transition is still poorly known. Here we report on an excavation at the Liang Abu rock shelter which has contexts dating from the Late Pleistocene (12,660 ± 58 uncal. BP) to the present day, indicating a terminus ante quem (TAQ) for human occupation at 23,790 BP. We present the results of an attempt to systematically integrate and compare data from Liang Abu and Kimanis, a geographically close site with a previously published sequence. Particular attention is paid to post-depositional issues in tropical settings and to data compatibility, reuse, and reproducibility, relying on open-source software for data processing (R scripts) and Bayesian chronological modeling. Two Bayesian models are built and compared using the ChronoModel software, which can handle outliers and uncertainty (e.g., freshwater reservoir effect). This first inter-site comparison for Borneo results in a new chronology of human settlement and mainland–coastal interactions in East Borneo and paves the way for future regional synthesis. [ABSTRACT FROM AUTHOR]

The Fang'an gold deposit in the Wuhe area, Anhui Province, is located in the area adjacent to the Bengbu Uplift and Wuhe Platform Depression in the southeastern part of North China. This study aimed to determine the deposit's mineralization age and the source of its metallogenic materials and mineralization processes through investigations into its geological characteristics, Rb–Sr isotopes, and S–Pb isotopes. The orebodies of the Fang'an gold deposit in the Neoarchean Xigudui Formation primarily exhibit a vein-type structure. The ore-forming process can be divided into four stages: (i) the quartz stage (Py1); (ii) the quartz–pyrite stage (Py2); (iii) the polymetallic sulfide stage (Py3); and (iv) the carbonate stage. Of these, the main mineralization stage is also the main period in which gold mineralization occurs. In situ sulfur isotope results of pyrite (Py1 to Py3) in the first three mineralization stages, suggesting a contribution of sulfur from crust–mantle magmatic fluids. The δ34S values for Py2 (average 5.51‰) are higher than Py1 (average 4.45‰) and showed that the magmatic fluids mixed with meteoric waters. The δ34S values for Py3 (average 5.18‰) are lower than Py2 (average 5.51‰), revealing that it related fluid immiscibility. The lead isotopic compositions of sulfides within the ores possessed 206Pb/204Pb ratios ranging from 16.759 to 16.93, 207Pb/204Pb ratios ranging from 15.311 to 15.402, and 208Pb/204Pb ratios ranging from 37.158 to 37.548. These lead data were plotted close to the Xigudui Formation, relatively distant from the Mesozoic granites, indicating that the Xigudui Formation was the source of lead for the Late Mesozoic ores of the deposit. Taken together, due to the degassing of mantle-derived magma in the shallow parts of the crust, it can be determined that the sources of ore-forming sulfur and lead were crust–mantle magmatic activities in the Wuhe area. Rb–Sr dating of pyrite from Fang'an gold deposit reveals that the mineralization occurred at 126.89 ± 0.58 Ma. Considering the previous research into the dating of magmatic rocks in the Wuhe area, we propose that the genesis of the Fang'an gold deposit is closely associated with magmatic activities in the area at around 130 Ma. [ABSTRACT FROM AUTHOR]

In this study, zircon U‐Pb dating of volcanic rocks from the Zhongba ophiolite of the Yarlung Zangbo Suture Zone (YZSZ) in southern Xizang (Tibet) yielded an age of 247 ± 3 Ma. According to whole rock geochemical and Sr‐Nd‐Pb isotopic data, the Early Triassic samples could be divided into two groups: Group 1 with P‐MORB affinity, showing initial 87Sr/86Sr ratios of 0.70253–0.70602, εNd(t) values of 4.2–5.3, (206Pb/204Pb)t ratios of 16.353–18.222, (207Pb/204Pb)t ratios of 15.454–15.564, and (208Pb/204Pb)t ratios of 35.665–38.136; Group 2 with OIB affinity, showing initial 87Sr/86Sr ratios of 0.70249–0.70513, εNd(t) values of 4.4–4.9, (206Pb/204Pb)t ratios of 17.140–18.328, (207Pb/204Pb)t ratios of 15.491–15.575, and (208Pb/204Pb)t ratios of 36.051–38.247. Group 2 rocks formed by partial melting of the mantle source enriched by a former plume, and assimilated continental crustal material during melt ascension. The formation of Group 1 rocks corresponds to the mixing of OIB melts, with the same components as Group 2 and N‐MORBs. The Zhongba Early Triassic rocks belong to the continental margin type ophiolite and formed in the continental–oceanic transition zone during the initial opening of the Neo‐Tethys in southern Xizang (Tibet). [ABSTRACT FROM AUTHOR]

The influence of marine components in the study area is attributed to seafloor spreading and opening in the Indian Ocean during the Aptian, coupled with eustatic sea-level rise throughout the Aptian–Albian period. The present investigation delineates a marine incursion in the Chintalapudi sub-basin of the Godavari Valley Coalfield based on the occurrence of dinocysts, acritarchs and prasinophytes. Noteworthy stratigraphic marker taxa are recognized as key components in the age assignment of the sedimentary rocks. Sum total of four zones have been recognised in the studied part of the sequence. The oldest zone in the deepest set of sedimentation is identified as Cicatricosisporites australiensis Zone. This zone is assigned based on the first occurrence (FO) of Cicatricosisporites australiensis and Biretisporites eneabbaensis. The next zone, further above in the sequence is Foraminisporis wonthaggiensis Zone. The FO of Foraminisporis wonthaggiensis attested to the initiation of this zone. The third zone is Cyclosporites hughesii Zone recognised by the FO of Foraminisporis asymmetricus. The accessory palynotaxa comprised of Retimonocolpites sp., Tricolpites confessus, Tricolpites sp., Tricolporites sp. and Triporites sp. in the recognition of this zone. The youngest zone of this sequence is recognised at the top of the sequence named Crybelosporites striatus zone based on the FO of Crybelosporites striatus. Palynological analysis places the studied part of succession between the Berriasian to early Albian. The primary objective of this investigation is to explicate the characteristics of sedimentation and paleoenvironmental contexts, with a specific emphasis on utilizing palynofacies and Botryococcus morphotypes as distinct benchmarks. Based on the palynofacies investigation three different depositional regimes have been assigned, which are distinguished as follows: (a) continental (384.30–203.75 m) dysoxic–anoxic basin; (b) shallowest nearshore–inner shelf, marginal marine/brackish water settings; and (c) heterolithic proximal shelf deposition with significant sea transgression (94.50–36.50 m). Unpredictable morphotaxonomical responses across diverse habitats with varying pH levels are projected to enhance comprehension of the palaeoecological and palaeoenvironmental significance of fossil Botryococcus colonies. The uppermost marine part of the sequence denotes the least abundance, reduced size, and ill-defined amorphous forms of fossil Botryococcus colonies. The continental part displays the less abundant but well-defined and fully grown sporadic distribution of fossil Botryococcus colonies; the middle part records its presence with a well-diversified, sturdy structural framework and cellular cup-like structures. The investigation of the Cretaceous strata reveals a dynamic geological history influenced by tectonic activities, including plate drifting and rifting. Present investigation enhances our comprehension of palynostratigraphy, and paleoenvironmental history and facilitates the formulation of models elucidating environmental processes during the Early Cretaceous. In addition, the lipid-rich composition of Botryococcus renders it promising for biofuel production, attracting attention in biotechnology and renewable energy research endeavors. [ABSTRACT FROM AUTHOR]

High-resolution dating of volcanic rocks is the foundation for understanding the evolution of volcanoes and for estimating possible hazards. However, dating is often difficult for submarine volcanoes, where radiocarbon or other dating is frequently unavailable or imprecise. Here, we report paleointensity results from submarine basalts around Izu-Oshima Island, a typical island-arc volcano, and their bearing on age constraints. Basaltic lava samples were collected from submarine ridges located southeast of Izu-Oshima Island. Rock magnetic data indicate that the samples contain Ti-rich titanomagnetite with blocking temperatures of around 250–400 °C. The magnetic properties of the samples do not change significantly when heated in Ar or vacuum. We apply the Tsunakawa-Shaw method to estimate absolute paleointensity. Samples from different submarine ridges show distinct behavior. One ridge (SE1) shows moderate paleointensity of about 37 μT, while another ridge (SE3) records relatively strong magnetic fields of about 60 μT. Comparing those results with regional paleointensity data, we estimate the age of the SE1 ridge to be younger than 0.5 ka or around 1.4 ka. The other ridge (SE2) exhibits different paleointensity for two samples obtained from different localities, implying that the ridge consists of multiple eruptions. These results demonstrate that paleomagnetism can improve the dating of submarine volcanic rocks. [ABSTRACT FROM AUTHOR]

Direct dating of vertebrate fossils is difficult due to complex postburial diagenetic processes and the often low and heterogeneous concentration of radioisotopes (e.g., U) in fossilized bone material. Here, we demonstrate a novel approach to dating vertebrate fossils via laser ablation–inductively coupled plasma–mass spectrometry U-Pb dating of early diagenetic calcite cements precipitated within bone cavities of a Jurassic sauropod from the Sichuan Basin, South China. Early diagenetic calcite yielded a U-Pb age of 165.3 ± 3.6/5.6 Ma, in agreement with a maximum depositional age of 165.8 ± 1.0 Ma from detrital zircon ages of the surrounding rocks, suggesting that diagenesis occurred shortly after the death of the sauropod. This new age demonstrates that the best-known Jurassic large sauropod faunas in South China are much older than those in North America and Africa, suggesting the geographical isolation of South China. Authigenic apatite U-Pb dating on the fibrolamellar bones from the same sauropod gave a distinctly younger age, indicating more complex U-Pb system behavior, possibly due to U uptake by residual organic matter and recrystallization of apatite after early diagenesis. Our findings demonstrate that U-Pb dating of calcite cements within bone cavities has significant potential for constraining the burial age of vertebrate fossils, which could aid in constructing a more robust temporal framework for the radiation and evolution of vertebrates. [ABSTRACT FROM AUTHOR]

The Klamath Mountains in northern California and southern Oregon are thought to record 200+ m.y. of subduction and terrane accretion, whereas the outboard Franciscan Complex records ocean‐continent subduction along the North American margin. Unraveling the Klamath Mountains' Late Jurassic history could help constrain this transition in subduction style. Key is the Mesozoic Condrey Mountain Schist (CMS), comprising, in part, a subduction complex that occupies a structural window through older, overlying central Klamath thrust sheets but with otherwise uncertain relationships to more outboard Klamath or Franciscan terranes. The CMS consists of two units (upper and lower), which could be correlated with (a) other Klamath terranes, (b) the Franciscan, or (c) neither based on regional structures and limited extant age data. Upper CMS protolith and metamorphic dates overlap with other Klamath terranes, but the lower CMS remains enigmatic. We used multiple geochronometers to constrain the timing of lower CMS deposition and metamorphism. Maximum depositional ages (MDAs) derived from detrital zircon geochronology of metasedimentary rocks are 153–135 Ma. Metamorphic ages from white mica K‐Ar and Rb‐Sr multi‐mineral isochrons from intercalated and coherently deformed metamafic lenses are 133–116 Ma. Lower CMS MDAs (<153 Ma) predominantly postdate other Klamath terrane ages, but subduction metamorphism appears to start before the earliest coherent Franciscan underplating (ca. 123 Ma). The lower CMS thus occupies a spatial and temporal position between the Klamath Mountains and Franciscan and preserves a non‐retrogressed record of the Franciscan Complex's early history (>123 Ma), otherwise only partially preserved in retrogressed Franciscan high grade blocks. Key Points: The Condrey Mountain Schist (CMS) epidote‐blueschist facies rocks were deposited and underplated in the Late Jurassic to Early CretaceousUnderplating postdates Klamath terrane assembly and predates coherent Franciscan underplating, recording the early Franciscan historyCMS pressure‐temperature conditions are consistent with other estimates of early Franciscan subduction zone thermal structure [ABSTRACT FROM AUTHOR]

Enicocephalomorpha, also known as uniqueheaded bugs, are a seldom-collected infraorder of heteropteran insects whose evolutionary relationships have puzzled entomologists for more than a century. Unique-headed bugs are exceptionally rare in the fossil record, which hinders our understanding of the morphological transformations of the lineage across time and also affects the calibration of molecular clock estimates used to date the origins of the infraorder. Here, we report the discovery of Enicocephalinus ibericus sp. nov. from Iberian amber in the Ari~no deposit in Spain, early Albian (Early Cretaceous) in age. The new species represents the second oldest fossil enicocephalomorphan to date, and the second record of this infraorder from European deposits. Remarkably, the closest relative of E. ibericus is the congeneric E. acragrimaldii Azar from Lebanese amber that is c. 20 myr older (Barremian), indicating a long-term persistence of the Enicocephalinus lineage across geological time. A review of the existing literature enabled us to record a total of 20 congeneric insect species that have been found in both Lebanese and Iberian ambers, suggesting the existence of previously underappreciated entomofaunal connections between southern Laurasia (the European archipelago) and northern Gondwana during the Cretaceous. We show that the palaeoentomological record holds remarkable potential for elucidating the faunistic exchanges and palaeobiogeographical patterns in the peri-Tethyan region during the Cretaceous. [ABSTRACT FROM AUTHOR]

A geochronological and isotope–geochemical study of alkaline basalts from three areas of young magmatism within the northeastern part of the Arabian Plate (Southeastern Turkey), Batman, Kurtalan and Alemdağ, was carried out. The obtained isotope data have indicated that the volcanism in the studied region developed over a 5-Ma period from the end of Miocene to the middle Pleistocene during four pulses separated by breaks in magmatic activity: 6.1–4.9 Ma (Batman area, hawaiites), ~3.0 Ma (Alemdağ plateau, phase I, basalts), 2.0–1.9 Ma (Alemdağ plateau, phase II, tephrites), and 1.5–1.3 Ma (Alemdağ plateau, phase III, basalts; Kurtalan area, basalts). A comparison of spatial–temporal changes of magmatic activity evolution in the studied part of the Arabian Plate and within the largest basalt plateau of Arabian foreland, Karacadağ Plateau, located to the west, was carried out. The results of Sr–Nd–Pb isotope–geochemical studies show that the development of young basalt volcanism in the Arabian Plate was characterized at different time by the contribution of various mantle sources in magma generation under this region. Initial pulses of magmatic activity are associated with melting of Arabian subcontinental lithospheric mantle (SCLM). The processes of fractional crystallization combined with crustal assimilation (AFC) have played an important role in the petrogenesis of lavas as well. Later, a deep mantle source (PREMA) with a depleted isotopic composition played a leading role in the formation of basaltic magmas of increased alkalinity. The melts generated by this source were mixed with the SCLM material in various proportions at different stages of magmatism with a limited participation of AFC processes in the petrogenesis of the rocks. It was concluded that young basalt volcanism of increased alkalinity in the northeast of the Arabian Plate is not related to the collision of the Eurasian and Arabian plates genetically, but presumably manifested here as a result of the migration of the initial rift geodynamic setting from the Red Sea basin to the north along Levantine and East Anatolian transform faults due to directed convection flows in the lower part of mantle under this part of the Earth. [ABSTRACT FROM AUTHOR]

The main structural building blocks that form manganese oxides are MnO6 octahedra; these share corners and edges to construct specific structures, which can either be tunneled or layered. In the layered structures, that is, phyllomanganates, the MnO6 octahedra form sheets, which, in turn, alternate with sheets of metal oxides and H2O. These metal ions can vary (Zn, Co, Ni, Al, Li, ...) and give rise to an entire range of different metal oxides. The characterization of these layered materials is important as they have various economical/industrial applications. Birnessite‐type materials, a specific type of layered manganese oxides, are widely studied for their use as cathode materials in alkali‐ion batteries. Phyllomanganates are also commonly found as constituents in sediments and soils or as coatings on rock surfaces. Their natural occurrence as black colored components have ensured that these minerals were also applied as pigments in archaeological and historical contexts. They are, for example, often found in rock art paintings and on pottery. As the oxides are used in unique archaeological objects, Raman spectroscopy is an evident choice for characterization due to its non‐destructive nature of analysis. In the current study, five mineral samples of (layered) manganese oxides are analyzed with different Raman instrumentations, including mobile systems and a benchtop micro‐Raman setup. The characterization of each selected manganese oxide and their comparison with literature data is discussed for the micro‐Raman instrumentation. In addition, the ability of identifying and characterizing layered manganese oxides and the possible challenges when using mobile instrumentation are discussed as well. [ABSTRACT FROM AUTHOR]

The Longshou Shan, located in western China, plays a crucial role in connecting the Tarim Continent with the North China Craton. It provides valuable insights into the Cenozoic intracontinental deformation, the complex dynamics of Eurasian tectonics, and the relationship between the pre-Cenozoic Tethys and Central Asian orogenic systems. Consequently, comprehending the evolution of the Phanerozoic era in this region holds immense significance. Zircon (U-Th)/He (ZHe) dating was conducted on three granite samples (n = 18) collected from the Longshou Shan. The ZHe dates of these granite rocks range from 7.2 to 517.7 Ma, showing a negative correlation with eU values. Furthermore, a limestone sample from the Longshou Shan yielded ZHe (n = 4) ages of 172.0–277.1 Ma and AHe (n = 4) ages of 17–111.9 Ma. The area has undergone complex tectonic processes involving multiple phases of uplift and burial. Using both forward and inverse modeling methods, we aim to establish plausible thermal histories. Our models reveal: (1) Late Paleozoic unroofing; (2) Early Mesozoic cooling and Late Mesozoic regional stabilization; and (3) Cenozoic reheating and subsequent cooling. By investigating the intricate thermal history of the Longshou Shan through multi-method modeling, we compare different approaches and assess the capabilities of single ZHe dating for understanding a thermal history. This research contributes to unraveling the region's geological complexities and aids in evaluating various modeling methods. [ABSTRACT FROM AUTHOR]

Study on the petrology, LA-ICP-MS zircon U-Pb dating and whole rock geochemistry of the trachyandesite in Wufeng area of Yanbian, Jilin Province in Northeast China, shows that the SiO2 content is 58.33%-61.36%, K2O content 1.61%-3.28% and total alkali content 6.77%-10%, belonging to the medium potassium-high potassium calc-alkaline series. The weighted mean age of magmatic zircon 206Pb/238U is 175.52±2.7 Ma, which is consistent with the subduction time of Early Jurassic paleo-Pacific plate. The trachyandesite is characterized by relative enrichment of LILEs(K, Ba and Rb) and strongly incompatible elements (Th and U), and depletion of HFSEs (Nb, Ta and Ti), with high LREE/HREE ratio, and enriched LREEs and depleted HREEs, indicating that the magma may originate from the partial melting of mantle and its source area is metasomatized by the subducted shell source materials. From the above, it is believed that the trachyandesite was formed in the active continental margin of oceanic subduction system and was the magmatic response to the subduction of Early Jurassic paleo-Pacific plate. [ABSTRACT FROM AUTHOR]

There has been no consensus yet regarding the precise initial timing and duration of the late Mesozoic extensional tectonics in the South‐eastern China Block. This work focusses on the growth strata of the Early Cretaceous red beds in the South‐eastern China Block to determine the late Mesozoic tectonics and the precise timing of the initiation and duration of extensional tectonics in this area. Field observation of several terrigenous basins shows that the dip angles of the Cretaceous red beds have varied from moderate to gentle from basin edges to interiors (or centres). The visible and estimated thickness within a single bed increases slightly downwards from the upper to the lower part. These characteristics indicate that the sedimentary area of these beds has undergone an extensional process with expansion and deepening of the sedimentary basins. Rotation of the border surfaces (limbs) and downward warping of the hanging walls or retreat of the footwalls of listric normal faults causes three types of extensional growth (or syntectonic) strata in the deposits of different basins. Dating of the volcanic rocks related to the growth beds reveals that the sedimentary basins were enlarged and deepened when the Early Cretaceous strata were deposited in the South‐eastern China Block from ca 140 to 137 Ma. Regionally, under the influence of Palaeo‐Pacific plate rollback since ca 140 Ma, the South‐eastern China Block stress field has led to lithospheric uplift and pull‐apart structures near the surface, causing the half‐graben basins to receive sedimentation. Although the extensional event was interrupted by a short compressional event during 120 to 105 Ma, with the oceanward retreat of the trench, the area of extension gradually enlarged and rejuvenated south‐eastwards until the end of the Cretaceous. This Cretaceous extension event of the South‐eastern China Block must belong to a worldwide geological event with global significance. [ABSTRACT FROM AUTHOR]

Footprints represent a relevant vestige providing direct information on the biology, locomotion, and behaviour of the individuals who left them. However, the spatiotemporal distribution of hominin footprints is heterogeneous, particularly in North Africa, where no footprint sites were known before the Holocene. This region is important in the evolution of hominins. It notably includes the earliest currently known Homo sapiens (Jebel Irhoud) and the oldest and richest African Middle Stone Age hominin sites. In this fragmented ichnological record, we report the discovery of 85 human footprints on a Late Pleistocene now indurated beach surface of about 2800 m2 at Larache (Northwest coast of Morocco). The wide range of sizes of the footprints suggests that several individuals from different age groups made the tracks while moving landward and seaward across a semi-dissipative bar-trough sandy beach foreshore. A geological investigation and an optically stimulated luminescence dating of a rock sample extracted from the tracksite places this hominin footprint surface at 90.3 ± 7.6 ka (MIS 5, Late Pleistocene). The Larache footprints are, therefore, the oldest attributed to Homo sapiens in Northern Africa and the Southern Mediterranean. [ABSTRACT FROM AUTHOR]

Metazoans use silicon traces but rarely develop extensive silica skeletons, except for the early-diverging lineage of sponges. The mechanisms underlying metazoan silicification remain incompletely understood, despite significant biotechnological and evolutionary implications. Here, the characterization of two proteins identified from hexactinellid sponge silica, hexaxilin and perisilin, supports that the three classes of siliceous sponges (Hexactinellida, Demospongiae, and Homoscleromorpha) use independent protein machineries to build their skeletons, which become non-homologous structures. Hexaxilin forms the axial filament to intracellularly pattern the main symmetry of the skeletal parts, while perisilin appears to operate in their thickening, guiding extracellular deposition of peripheral silica, as does glassin, a previously characterized hexactinellid silicifying protein. Distant hexaxilin homologs occur in some bilaterians with siliceous parts, suggesting putative conserved silicifying activity along metazoan evolution. The findings also support that ancestral Porifera were non-skeletonized, acquiring silica skeletons only after diverging into major classes, what reconciles molecular-clock dating and the fossil record. Sponges, being early-diverging metazoans and the only animals to develop extensive skeletons of silica, have potential to inform about the evolutionary steps of metazoan traits, including biomineralization. Here, the authors characterize two proteins associated with the hexactinellid sponge silica. [ABSTRACT FROM AUTHOR]

Unveiling the tempo and mode of animal evolution is necessary to understand the links between environmental changes and biological innovation. Although the earliest unambiguous metazoan fossils date to the late Ediacaran period, molecular clock estimates agree that the last common ancestor (LCA) of all extant animals emerged ~850 Ma, in the Tonian period, before the oldest evidence for widespread ocean oxygenation at ~635–560 Ma in the Ediacaran period. Metazoans are aerobic organisms, that is, they are dependent on oxygen to survive. In low‐oxygen conditions, most animals have an evolutionarily conserved pathway for maintaining oxygen homeostasis that triggers physiological changes in gene expression via the hypoxia‐inducible factor (HIFa). However, here we confirm the absence of the characteristic HIFa protein domain responsible for the oxygen sensing of HIFa in sponges and ctenophores, indicating the LCA of metazoans lacked the functional protein domain as well, and so could have maintained their transcription levels unaltered under the very low‐oxygen concentrations of their environments. Using Bayesian relaxed molecular clock dating, we inferred that the ancestral gene lineage responsible for HIFa arose in the Mesoproterozoic Era, ~1273 Ma (Credibility Interval 957–1621 Ma), consistent with the idea that important genetic machinery associated with animals evolved much earlier than the LCA of animals. Our data suggest at least two duplication events in the evolutionary history of HIFa, which generated three vertebrate paralogs, products of the two successive whole‐genome duplications that occurred in the vertebrate LCA. Overall, our results support the hypothesis of a pre‐Tonian emergence of metazoans under low‐oxygen conditions, and an increase in oxygen response elements during animal evolution. [ABSTRACT FROM AUTHOR]

A hominin mandible, KNM-ER 63000, and associated vertebrate remains were recovered in 2011 from Area 40 in East Turkana, Kenya. Tephrostratigraphic and magnetostratigraphic analyses indicate that these fossils date to ∼4.3 Ma. KNM-ER 63000 consists of articulating but worn and weathered mandibular corpora, with a broken right M 2 crown and alveoli preserved at other tooth positions. Despite extensive damage, KNM-ER 63000 preserves diagnostic anatomy permitting attribution to Australopithecus anamensis. It can be distinguished from Australopithecus afarensis by its strongly inclined symphyseal axis with a basally convex, 'cut-away' external surface, a lateral corpus that sweeps inferomedially beneath the canine-premolar row, and alignment of the canine alveolus with the postcanine axis. KNM-ER 63000 is distinguished from Ardipithecus ramidus by its thick mandibular corpus and large M 2 crown. The functional trait structure and enamel's stable carbon isotopic composition of the Area 40 large-mammal community suggests an environment comparable to Kanapoi and other ∼4.5–4 Ma eastern African sites that would have offered Au. anamensis access to both C 3 and C 4 food resources. With an age of ∼4.3 Ma, KNM-ER 63000 is the oldest known specimen of Au. anamensis , predating the Kanapoi and Asa Issie samples by at least ∼100 kyr. This specimen extends the known temporal range of Au. anamensis and places it in temporal overlap with fossils of Ar. ramidus from Gona, Ethiopia. The morphology of KNM-ER 63000 indicates that the reconfigured masticatory system differentiating basal hominins from the earliest australopiths existed in the narrow temporal window, if any, separating the two. The very close temporal juxtaposition of these significant morphological and adaptive differences implies that Ar. ramidus was a relative rather than a direct phyletic ancestor of earliest Australopithecus. [ABSTRACT FROM AUTHOR]

The Tacna region in southern Peru hosts archaeological remnants of Pre-Columbian period human occupations, including the Miculla Petroglyphs. Existing methods for dating these petroglyphs present substantial uncertainties and are subject to claims lacking objective validation. This study employs advanced hyperspectral analysis, specifically utilizing the SPECIM IQ camera, to reevaluate existing chronological proposals for these petroglyphs. The employed analytical technique is non-destructive and captures spectral data across an extensive range of wavelengths. This allows for a quantitative assessment of patination levels attributable to solar exposure, in comparison to adjacent intact areas. Data from various petroglyphs were analyzed using SPECIM IQ Studio software and Matlab. The analysis differentiated between "engraved" and "varnished" regions on selected boulders. Reflectance ratios between these areas were compared to provide insights into the potential relative ages of different sets of engravings. The results question pre-existing chronologies based on cultural classification schemes for the petroglyphs. While the study underscores the utility of hyperspectral analysis in refining petroglyph dating, it also indicates that this method cannot replace a multi-method approach without further resolution refinement. • Hyperspectral analysis suggests time-dependent varnish patterns for Miculla Petroglyphs. • Patination levels assessed via SPECIM IQ camera across extensive wavelengths. • Reflectance ratios hint at varying ages for different petroglyph sets. • Study presents a methodology requiring statistical analysis for robust dating. • Future work advocates multi-method approach combining HSI with other dating methods. [ABSTRACT FROM AUTHOR]

Miocene petrified tree fossils in tuffs from Lesvos Island show a variety of types of mineralization. Trees from the older part of the volcanic succession, including the well-known Petrified Forest near Sigri, are brilliant yellows, reds and browns as a result of Fe–Mn hydrothermal alteration post-dating silicification. Trees from the younger part of the volcanic succession on the southeastern flank of the volcanic chain include some in which the original carbon has not been replaced, others that are completely silicified or completely replaced by calcite, and yet others with cell walls silicified and the lumina filled with a variety of carbonate and sulfide minerals. Widespread Fe–Mn hydrothermal veins are found only in the older part of the volcanic succession and in underlying basement rocks and date from the inversion of the Sigri basin in the mid-Burdigalian and the intrusion of the Mesotopos dykes and laccoliths. The variable petrifaction of fossil wood is thus essentially a consequence of the variability of diagenetic and hydrothermal processes. This study demonstrates the importance of tectonic history in localising volcanic hydrothermal circulation and hence diversity in style of petrifaction. • Silicified trees in tuffs in western Lesvos show late Fe–Mn mineralization. • Mineralization at depth after basin inversion and laccolith intrusion. • In tuffs in eastern Lesvos, incomplete tree petrifaction by silica and/or carbonates. • Mineralization at shallow depths, no basin inversion, some basement leaching. • Petrified trees provide record of diagenetic and hydrothermal history of host tuffs. [ABSTRACT FROM AUTHOR]

Bearded Vultures deliberately stain their feathers with iron oxides from ferruginous springs (FS) to acquire orange colouration. This uncommon behaviour is believed to play an important role in the relationship between individuals, so FS may constitute a strategic resource for the species. In the French Central-Western Pyrenees, we surveyed and mapped FS, checked those used by Bearded Vultures and characterised their habitat variables and geological features. We also evaluated FS availability in Bearded Vultures’ home ranges and their conservation status. FS occurred in relatively large number (more than three hundred) in the study area, spatially distributed in a very heterogeneous way. Sedimentary or metamorphic rocks dating from the Palaeozoic Era (–541 to –252 million years ago) hold majority of them, with schists being the predominant rock type (62.1%). FS were near absent from limestone massifs of the North-Pyrenean zone and from granite formations of the axial zone. We found evidences of use by Bearded Vultures in a limited number of sites (n = 27 out of 339 localised FS). These colouring sites were characterised by steep slopes, intense coloured iron oxide deposits and a location usually close to the forest edge. Availability of colouring sites for breeding Bearded Vultures (n = 32 pairs or trios in the study area) was high enough: we localised a mean of 36.9 available FS and 2.6 used FS in a 15 km-radius around the usual breeding site of each pair/trio. The mean distance between a breeding site and the nearest known colouring site was 8.8 ± 0.86 km, a minor flight distance for this species. The conservation status of the used FS seems generally satisfactory, although one site disappeared due to drought and three others were damaged by domestic livestock trampling or wild ungulates. The vicinity of cables or fences, i.e. potential mortality factors, also concerns three of the used FS. We recommend to consider these colouring sites as key resources for the species and to protect them from any damage. [ABSTRACT FROM AUTHOR]

A technique for parameterizing rock surfaces for luminescence surface exposure dating involves the use of known age rock surfaces which may host no surficial alterations or weathering rinds. However, exposure dated rock surfaces often host subsurface weathering rinds or foreign surficial components, which may impact the development of luminescence depth profiles in the rock material. To observe any effects of depth profile development and parameterizations of naturally altered rock surfaces, controlled exposure experiments were conducted on surface altered and surface non-altered luminescence saturated quartzite samples from the top and bottom portions of rock surface cores, collected from two erratic members of the Foothills Erratics Train, Alberta. Spatially resolved OSL laser scanning techniques were used to acquire two-dimensional OSL maps of the surface core samples for depth profile generation. Results produced varied intensities of depth profile data scatter and depth profile parameterizations between surface altered and non-altered samples. Several cores which exhibited surface alterations produced lower attenuation coefficients than comparable cores with no surface alterations, possibly from the effects of surface features and weathering rinds attenuating light intensity for OSL stimulation. These trends indicate samples hosting surface alterations such as weathering rinds, lichen cover, and staining may offer parameterizations which are inequivalent to rock surfaces with no surface altered components, and that depth dependent, multi-order parameterizations may be needed to adequately parameterize rock surfaces hosting surface altered features for exposure dating. • Spatially resolved OSL maps are produced from weathered and nonweathered quartzite surfaces. • Lower light attenuation values are generally fitted from weathered surface samples. • Weathering rinds, surface coverage may reduce OSL bleaching deeper into the subsurface. [ABSTRACT FROM AUTHOR]

The coupled ESR and U-series (ESR/U-series) method has been increasingly utilized for dating fossil teeth from Early to Middle Pleistocene hominid sites. One significant advantage of this method is its ability to directly analyze fossil animal or human teeth. However, compared with other radiometric methods such as 14C charcoal dating, U-series carbonate dating, and OSL sediment dating, this dating method is rarely employed for Late Pleistocene or younger sites. In this study, we present an ESR/U-series dating investigation conducted at the Naminan site, a Paleolithic-Neolithic transition (P–N transition) site situated on the Sino-Myanmar border. The ESR/U-series analysis of eleven dental samples yields an age range of 18.1–13.2 ka for the fossils. These obtained ages are generally consistent with the 14C chronology of the site. When dealing with young fossil samples, it was observed that due to relatively low uranium concentration in dental tissues, internal dose rate plays a less significant role compared to external beta and gamma dose rates in the total dose rate of the fossil samples. Consequently, evaluating the dose rate of surrounding sediment becomes a primary source of uncertainty. Additionally, in this study we attempted to employ the standardized growth curve (SGC) and representative dose response curve method for determining Equivalent Dose (D E), which was then compared with values obtained using additive dose method (ADM). Although the precision of D E estimated by two methods are comparatively lower than that of ADM, it demonstrates the potential to efficiently determine a more rational D max for irradiation, identify samples with stratigraphic disturbances, and analyze small or valuable fossil specimens. • Coupled ESR/U-series method was first applied to a P–N transition site in China. • SGC were tested to determine the D E of Late Pleistocene fossil samples. • The fossil ages calculation was independent with different U-models. [ABSTRACT FROM AUTHOR]

The existing radiocarbon (14C) dating framework for Lagar Velho is broadly consistent but provides limited constraint on several geoarchaeological complexes (GCs) and does not favour detailed chronological comparisons across all sectors of the site; including the stratigraphically disconnected child burial complex in the east area and the broader archaeological sequence in the central-west area. In this study, we undertake a complementary chronological assessment of Lagar Velho Rock Shelter using single-grain quartz OSL, single-grain quartz TT-OSL and combined U-series/ESR dating of fossil teeth, with the aim of establishing more comprehensive reconstructions of archaeological events and placing the human occupation sequence in a firmer regional climatic context. Expanding on the original chronological study, we also compare the published 14C datasets against widely used sample quality indicators (i.e., organic preservation and contamination proxies) to ensure reliable comparisons with our new luminescence and combined U-series/ESR ages. Eight 14C samples pass our combined chronological and stratigraphic hygiene criteria and are included in the final dating evaluations. Ten of the twelve optical dating samples produce homogeneous equivalent dose (D e) datasets indicative of suitable daylight exposure. The replicate single-grain TT-OSL D e datasets exhibit more pronounced scatter, consistent with enhanced potential for insufficient bleaching of TT-OSL residual doses in some karst settings. The fossil enamel samples dated using U-series/ESR span relatively low natural dose ranges, necessitating the inclusion of maximum dose (D max)-adjusted dose response curve fitting and additional background noise subtraction to avoid D e biases of up to 13%. Stratigraphically consistent ages (n = 26) spanning the full archaeological infill sequence are obtained using the four different dating methods, providing a robust interpretive framework and underscoring the significant role of single-grain OSL and combined U-series/ESR dating for refining early Upper Palaeolithic histories of Iberia. Bayesian modelling of the combined chronological dataset reveals a site accumulation history spanning 35,750–23,440 cal. BP and provides improved age constraints on all GCs; particularly the al , bs , tc , gs and ls deposits that were previously undated or imprecisely constrained. The age of the child burial complex is refined to 29,410–28,280 cal. BP, potentially occurring within Greenland Interstadial 4. Comparison of the modelled GC ages from the east and west-central areas enables improved temporal correlations of depositional events across stratigraphically disconnected sectors of the site. This analysis suggests that the child burial complex and the Late Gravettian occupation are statistically indistinguishable based on current dating evidence. The new dating assessments reveal three periods of human occupation at Lagar Velho: the Late Gravettian (including the shorter duration child burial event) 31.6–26.0 ka from the end of Heinrich Stadial (HS) 3 until the emergence of HS2; the Terminal Gravettian 26.5–24.5 ka coinciding with HS2; and the Middle Solutrean 25.2–23.4 ka extending from HS2 to the end of Greenland Stadial 3. The timing of these occupations during late Marine Isotope Stage (MIS) 3 and early MIS 2 highlights the significance of central western Portugal for supporting regional human populations during periods when much of Europe was experiencing extreme cold, aridity and expanded glacial coverage. • Consistent OSL, TT-OSL, US-ESR and 14C ages obtained for the archaeological sequence. • Bayesian modelling reveals site accumulation history spans 35,750–23,440 cal. BP. • Child burial age refined to 29,410–28,280 cal. BP, potentially within GI4. • Three human activity phases correspond with short-term climate cycles in MIS2. • Central-west Portugal was a key refugium for human populations during HS2 and LGM. [ABSTRACT FROM AUTHOR]

While flint and similar materials are some of the most often preserved finds from the pre-historic archaeological records, trapped charge techniques can currently only be used on heated flint pieces. Here, we investigate if rock surface luminescence dating using the light-sensitive OSL signal is applicable to unheated flint nodules and cobbles by measuring OSL signal-depth profiles in flint samples collected from eastern Zealand and Møn, Denmark. We demonstrate that a detectable, natural OSL signal is present in the centre in eight out of the nine investigated flint samples. Additionally, the OSL signal had been bleached to various depths at the flint surfaces, which were exposed to daylight at the time of sampling. The field-saturated OSL is 50% or lower compared to the laboratory OSL after a 6 kGy dose was administered to field-saturated flint slices; this discrepancy could be related to signal loss occurring over geological time scales, but the exact nature of the mechanism of signal loss remains unclear. The presence of a natural OSL signal that bleaches into the flint when exposed to daylight suggests that rock surface dating of unheated flints is feasible, and the method should be further tested on known-age samples. • Natural OSL is observed in geological flint from chalk deposits. • OSL-depth profiles from flint surfaces show signal bleaching when exposed to daylight. • Comparison between field-saturated and laboratory-saturated OSL in flint provides insight into OSL signal stability. • Early signal subtraction reduces the scatter in OSL-depth flint profiles. [ABSTRACT FROM AUTHOR]

Here we report luminescence dating results on exhumed fault rocks from the North Tehran Fault (NTF, Iran), including the fault gouges. The NTF is an oblique-dip thrust fault expanding from west to east at the northern fringe of the megacity of Tehran. Although the fault is known to be active and a major threat to the city, only little is known about its earthquake history. We present first data on the timing of past fault motion using dating of fault rocks. Three sites have been selected for this study in which the fault damage zone is associated with Eocene volcaniclastic rocks (Karaj Formation). The fault gouge, transitional and damage zone were sampled for which we observed slip planes in the field. The fault rocks are composed of quartz and alkali feldspar favourable for luminescence dating. However, our study reveals that the quartz optically stimulated luminescence (OSL) signal of the Karaj Formation does not seem to have a measurable fast decaying signal component. Instead, the post-infrared stimulated luminescence at 225 °C (pIRIRSL 225) of polymineral fine-grain fraction appears to be the most feasible signal for these samples. The first luminescence-based results presented here comprise an age range from 45 ± 5 ka to 72 ± 13 ka for fault gouges and transitional zone. Since dating the transitional zone close to the fault gouge led to a younger age than the fault gouge at one site, we conclude that the sampling location plays a crucial role in dating exhumed fault rock using luminescence dating. The obtained ages are far older than those of the previous palaeoseismological studies that dated earthquake-related sedimentary features in the region. Therefore, more research is required to shed light on the resetting mechanism and condition of these fault rocks due to the recent activity of the NTF. [ABSTRACT FROM AUTHOR]

• Drill core samples constrain the age and evolution of the buried Wyoming Province. • Zircon U-Pb geochronology records Mesoarchean magmatism and metamorphism. • Reflector east of the Bighorn Mountains may juxtapose Archean terranes with similar ages and isotopic signature. • Geochemical, geochronologic, and geophysical data are most easily explained by a contiguous eastern Wyoming Province. • Integration of geologic, geochemical, geochemical, and geophysical datasets is critical to evaluate Archean and Proterozoic terrane boundaries. The extent and nature of the Wyoming Province, an Archean craton in southwestern Laurentia, are poorly understood due to limited exposure between spatially isolated basement-cored uplifts. This lack of exposure has led to debate about whether the northeastern Wyoming Province is underlain by contiguous Archean crust or Proterozoic rocks and suture zone associated with the Trans-Hudson orogeny. To assess these models we analyzed samples recovered from drill cores in the buried northeastern Wyoming Province that straddle the proposed Proterozoic suture. Whole-rock geochemical and Nd-Pb-O isotopic data suggest the rocks formed by partial melting of > 3.5 Ga hydrated mafic to tonalitic sources similar to elsewhere in the northern Wyoming Province. Zircon U-Pb dates record Mesoarchean magmatism and metamorphism (3.0–2.8 Ga). Published whole-rock Rb-Sr, hornblende and biotite K-Ar, and apatite fission track dates suggest these rocks have not been heated above 300 °C since 2.5–2.1 Ga. Geophysical potential field data are consistent across northeastern Wyoming contrasting with major discontinuities associated with documented Proterozoic orogens on all other margins of the Wyoming Province. Hence, geochemical, isotopic, and geochronologic data along with geophysical imaging can be most simply interpreted in terms of continuous Archean crust in the northeastern Wyoming Province. A geophysically-imaged reflector east of the Bighorn Mountains may juxtapose Archean terranes with similar ages and sources, similar to the boundary between the Montana metasedimentary terrane and Beartooth-Bighorn magmatic zone in the northwestern Wyoming Province. This work emphasizes the value of integrating geologic and geophysical constraints to constrain Archean provinces and their tectonic evolution. [ABSTRACT FROM AUTHOR]

Rock art is found in many different regions of the world, with ages dated from late Palaeolithic period to the present. However, determining the precise ages for such artworks with direct chronological methods is challenging. U-series dating of secondary carbonates can constrain the age of rock art if these carbonates stratigraphically connected to the art. Hitherto, U-series isotope-dilution analyses with multi-collector inductively-coupled plasma mass spectrometry (ID-MC-ICPMS) has been increasingly used for rock art dating. This approach can achieve U–Th isotope-ratio quantification at the per-mille or submille level, but requires chemical pretreatment using isotope spikes and results in a relatively low sampling resolution. While in situ U-series dating using laser ablation-MC-ICPMS (LA-MC-ICPMS) is significantly less precise than ID-MC-ICPMS analysis, it allows to collect spatially resolved data sequences on very thin samples (<1 mm). This is important for identification of open systems and the chronological integrity of the analyses. Therefore, we developed a new method for high spatial resolution U-series in situ analysis. A piece of homogeneous stalagmite was selected as an in-house standard (RM-C1) for U-series in situ dating analysis. RM-C1 contains high U (17.3 ± 1.0 μg/g) and low Th concentrations (<5 ng/g). The 234U/238U and 230Th/238U activity ratios of 1.0116 ± 0.0006 and 0.9525 ± 0.0013, respectively, corresponding to a U-series age of 303.5 ± 1.5 ka, were determined by the ID-MC-ICPMS analyses (n = 10). Using the RM-C1 standard, we were able to date the Dansgaard–Oeschger (D/O) 19 event (with an expected age of 68.9 to 70.3 ka) in a stalagmite to a range from 68.0 ± 2.0 to 71.2 ± 2.5 ka, with an average age of 69.6 ± 1.5 ka (n = 15). This demonstrates the accuracy and reproducibility of our dating protocol. Subsequently, we conducted U-series in situ dating of secondary carbonates associated with rock paintings with two samples from the Cangyuan shelter (CY2-4 and CY2-7) and two samples from the Wanrendong Cave (SL3-A and SL5-A) in Yunnan Province, southwestern China. These samples had high U-concentration (>4 μg/g) and negligible environmental Th. The carbonate layers immediately overlying the pigments of CY2-4 and CY2-7 were dated to 3.7 ± 0.3 and 3.2 ± 0.2 ka, respectively, suggesting that the Canyuan rock paintings belongs to a late Neolithic culture of this area. The pigment layer sandwiched in the sample SL3-A was bracketed to between 8.7 ± 0.3 and 10.1 ± 0.3 ka and in SL5-A to between 10.4 ± 0.3 and 10.8 ± 0.4 ka, implying that the Wanrendong rock paintings probably were created by a hunting-gathering population during the early Holocene. [ABSTRACT FROM AUTHOR]

The eastern flank of the Talesh range of western Alborz, northwestern Iran, exposes volumetrically significant Late Cretaceous volcanic and volcaniclastic associations as well as cross-cutting dykes and minor subvolcanic equivalents. The volcanic units appear as massive to pillowed flows interlayered with volcaniclastic beds and subordinate limestones. We present new field data, zircon U Pb ages, bulk-rock major and trace element geochemistry, and Sr Nd isotopes on the igneous rock suite. Geochemical data show that the lava units and dykes are mainly basaltic in composition with minor basaltic andesites and trachytes. They form two contrasting series of arc-related calc-alkaline (Group 1) and OIB-like (Group 2) rocks. The zircon U Pb age of Group 1 rocks is 95.6 ± 1.8 Ma (2σ), whereas for Group 2 rocks, cross-cutting relationships and stratigraphic constraints indicate a somewhat younger age. Group 1 rocks have 87Sr/86Sr (i) varying from 0.7038 to 0.7070 and ε Nd (t) values ranging from +0.5 to +5.0. Group 2 rocks have 87Sr/86Sr (i) = 0.7040–0.7065 and ε Nd (t) from −3.0 to +3.7. Trace element and isotopic modelling shows that the primitive Group 1 magmas were derived from a metasomatized mantle source enriched by the addition of ∼6–10 % sediment melt component, while Group 2 rocks are consistent with melts of an asthenospheric mantle source enriched by ∼1–5 % EMII component. Trace element modelling indicates that Group 1 rocks formed from ∼6–13 % partial melts of a spinel-garnet lherzolite with garnet:spinel ratios of 45:55 to 10:90, whereas primitive Group 2 melts were generated through ∼1–3 % partial melting of a garnet-spinel-lherzolite with garnet:spinel ratios of 90:10 to 80:20. We propose a geodynamic model in which a north-dipping Neotethyan slab beneath the western Alborz (Talesh area) continental margin produced arc assemblages of Group 1 rocks and subsequent slab rollback led to the upwelling of an asthenospheric mantle to generate OIB-like magmatism of Group 2 rocks in an extensional intra-arc to back-arc setting. [Display omitted] • The Talesh magmatic rocks are dominated by basaltic lavas. • They were emplaced during the Late Cretaceous. • The magmatic rocks include both arc-type calc-alkaline and OIB-like alkaline rocks. • The mantle source of arc-type rocks was enriched by slab-derived sediment melts. • Slab rollback triggered asthenospheric melting and formation of OIB-like magmas. [ABSTRACT FROM AUTHOR]

• First in-situ apatite U-Pb ages from pseudotachylytes. • The lower crust fails seismically during the early stages of continental collision. • Earthquakes create long-lived fluid pathways in the lower crust. Determining the precise age of fossil earthquakes is essential for understanding the tectonic setting in which they occurred. Pseudotachylytes are quenched frictional melts that occur along coseismic fractures and represent evidence of fossil earthquakes in the rock record. Here, we present the first in-situ apatite U-Pb ages for three samples from Lofoten in the northern Norwegian Caledonides, that occur within and adjacent to lower-crustal pseudotachylytes: a pristine pseudotachylyte, a mylonitized pseudotachylyte, and a mylonite that contains pseudotachylyte transposed into the shear plane. The apatite U-Pb ages are combined with cathodoluminescence and electron backscatter diffraction analysis to provide microstructural constraints on the interpretation of ages. Apatite shows evidence of either fragmentation and annealing, or dislocation creep in response to coseismic rupture. The results suggest that the short-lived thermal pulse generated by the earthquake is sufficient to reset the apatite U-Pb system. The age of 426 ± 19 Ma is interpreted to date lower-crustal seismicity during the early Caledonian orogeny. Later fluid-rock interaction along the same structures led to partial resetting of the apatite U-Pb systematics, indicating that seismic brittle failure of the lower continental crust occurs at the incipient stages of continental collision, and that the resulting structures are preferential pathways for later fluid flow in the otherwise impermeable anhydrous lower crust. [ABSTRACT FROM AUTHOR]

The claims that children's hand and footprints on formerly soft travertine at Qiusang, Tibet, are about 200 ka old and are the earliest rock art on the planet are reviewed. The uranium-thorium results are inconsistent with a previous age estimate of another set of such prints nearby, which is itself at odds with finger-drawn Tibetan letters at that site. The claims also ignore the high susceptibility of open-site calcite travertine to surface retreat by weathering and the likely removal of uranium by rainwater. Similarly, deposition of detrital thorium can occur in such porous and weathered carbonates. Both processes are known to increase age estimates of reprecipitated carbonate deposits significantly. There is no evidence that hominins of the Middle Pleistocene occupied the central Tibetan Plateau during the penultimate glacial period. Several issues are considered, and recommendations are made for resolving the controversy. • The difficulties with applying uranium-thorium analysis to the dating of travertine are illuminated. • The most recent sensational claims based on this dating approach concern an open travertine site in Tibet. • It has been proposed that some hand and footprints are in the order of 200,000 years old. • The discovery of Tibetan writing characters suggests that the travertine markings can only be less than 1300 years old. • The significant discrepancy in this and previous studies is explained by leaching of uranium. [ABSTRACT FROM AUTHOR]

In this study, we use luminescence rock surface dating to provide burial ages for buried surfaces of a large boulder now positioned on top of the ruins of the Neolithic Ba'ja village in Southern Jordan. Luminescence depth profiles for quartz optically stimulated luminescence (OSL), and feldspar infrared stimulated luminescence (IR 50) signals indicate that the boulder experienced a complex transport history of at least two exposure and two burial events before final emplacement. By comparing the fading-corrected feldspar IR luminescence burial ages derived from these rock surfaces with quartz OSL ages derived from sediment infill from the archaeological structures underneath the boulder, it is concluded that there was a rockfall event around 7–8 ka ago, possibly as the result of an earthquake. Whatever the nature of this event, it resulted in the first recorded movement of the boulder, when the rock was presumably dislodged on the hill slope but did not travel all the way to the settlement at the foot of the slope. About 3–4 ka ago, after the village had been abandoned and the rooms filled with rubble, further movement occurred, possibly initiated by an earthquake. This final transport event moved the boulder further downslope, embedding it in the cultural layers of the derelict settlement on top of the partially collapsed settlement walls. [ABSTRACT FROM AUTHOR]