Search

The axial Arcabuco-Floresta segment of the Eastern Cordillera basin, Colombia exhibits a complex geological history characterized by both along and across strike variations in deformation and exhumation, as well as magmatic activity, all of which provide valuable insights into the broader tectono-thermal evolution of the Andean region. In this study, we combine existing thermochronological data, with 16 new zircons (U-Th)/He and 9 new fission-track dates, and numerical modeling to investigate the thermal history in response to such anomalies across the axial Arcabuco-Floresta segment. Single grain ZHe data from Devonian to Lower Cretaceous strata range from 74 to 20 Ma. ZFT data from the same samples show a broader age distribution ranging from 200 to 70 Ma. The integration of different inverse modeling approaches suggests that cooling, here interpreted as exhumation, occurred in three distinct episodes which can each be linked to different regional tectonic interactions since the Late Cretaceous. Over this time, exhumation commenced in the northern and western parts of the basin and extended progressively through to the eastern and southern parts. The first episode, from the Late Cretaceous to Eocene is related to the accretion of different oceanic terranes related to Farallon Plate. The second, from the Oligocene to Middle Miocene, is interpreted as a probable compressional response to accretion of the Panamá-Chocó Arc, Nazca Plate and the Gorgona Terrane. The third, extending from the Middle Miocene to Pleistocene, may be associated with exhumation driven by far-field deformation resulting from the final collision phase of the Panamá-Chocó block with South America and its interaction with the Nazca and Caribbean plates. This last phase led to the complete emergence of the Eastern Cordillera and its development as an orographic barrier. No evidence was found suggesting any possible influence of thermal overprinting on the thermochronological data in the basin. [ABSTRACT FROM AUTHOR]

This study presents geochemical, petrophysical and seismic interpretation and modeling data of source and reservoir rocks of Eocene and Paleocene sequences of Balkassar oilfield, Potwar Basin, Pakistan. Integrated approaches were applied to evaluate structure and various rocks i.e., Patala, Lockhart and Chorgali formations. Grid of eleven seismic lines, well logs, well tops and ten fresh rock cutting samples were used. TOC content of Patala Formation ranges between 0.25 − 1.16 wt. %, with S2 values 0.11–0.63 mg HC/g rock, thus indicating poor to fair hydrocarbon potentialwhich issupported by no distinct presence of hydrocarbon peaks in pyrolysis-GC pyrograms. Petrographic analysis showed dominant presence of vitrinitic Type III and inertinitic Type IV kerogen phytoclasts with minor amount of AOM. High abundance of reworked vitrinite and inertinite phytoclasts appear to have influenced the vitrinite reflectance data. Basin modeling predicts Lockhart Formation began oil generation at 10.30Ma age at depth 1557 m and reached peak generation at 8.43Ma age at depth 1802 m. Patala formation began oil generation at 10.56Ma age at depth 1472 m and reached its peak generation at 8.43Ma age at depth of 1768 m. 3D horizon mapping depicts that Chorgali formation is uniformly distributed and faulted from northwest corner. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Petroleum Research & Studies is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The eastern Gulf of Papua, at the easternmost end of the Papuan Basin, has been subjected to extended seawater loading during the Cenozoic, allowing an investigation into the influence of seawater loading on the thermal development of the underlying rock layers in the oceanic basin. Utilising paleontological, lithologic and paleobathymetric data, along with present-day temperature fields, this study reconstructed the burial history, thermal history and maturity of the eastern Papuan Basin using PetroMod2012.2 1D software. Burial history curves for the virtual wells were employed to trace the evolutionary stages in different regions, revealing a positive relationship between predicted vitrinite reflectance (Ro) and modelled thermal history. Ro values displayed a gradual decrease from northeast to southwest, with higher Ro values observed in areas unaffected by seawater loading. The presence of seawater loading had a notable impact on thermal history, particularly influencing the upper boundary condition and the sediment–water interface temperature of the temperature field. This research enhances our understanding of the Meso-Cenozoic thermal history of the eastern Papuan Basin and reveals the factors influencing stratigraphic thermal evolution. KEY POINTS: The burial history curves record different tectonic backgrounds and coincide with the tectonic evolution of the basin, which is divided into four evolutionary stages. The trends of heat flow and maturity distribution in the study area are similar but show a gradual decrease from both northeast and southwest directions towards the central region. Seawater loading mainly affects the upper boundary condition of formation temperature (sediment–water interface temperature) and has little effect on the lower boundary condition (heat flow). [ABSTRACT FROM AUTHOR]

Burgess Shale-type deposits provide a wealth of information on the early evolution of animals. Questions that are central to understanding the exceptional preservation of these biotas and the paleoenvironments they inhabited may be obscured by the post-depositional alteration due to metamorphism at depth and weathering near the Earth's surface. Among over 50 Cambrian BST biotas, the Chengjiang and Qingjiang deposits are well known for their richness of soft-bodied taxa, fidelity of preservation, and Early Cambrian Age. While alteration via weathering has been well-investigated, the thermal maturity of the units bearing the two biotas has not yet been elucidated. Here we investigate peak metamorphic temperatures of the two deposits using two independent methods. Paleogeotemperature gradient analyses demonstrate that the most fossiliferous sections of the Chengjiang were buried at a maximum depth of ∼8 500 m in the Early Triassic, corresponding to ∼300 °C, while the type area of the Qingjiang biota was buried at a maximum depth of ∼8 700 m in the Early Jurassic, corresponding to ∼240 °C. Raman geothermometer analyses of fossil carbonaceous material demonstrate that peak temperatures varied across localities with different burial depth. The two productive sections of the Chengjiang biota were thermally altered at a peak temperature of approximately 300 °C, and the main locality of the Qingjiang biota experienced a peak temperature of 238 ± 22 °C. These results from two independent methods are concordant. Among BST deposits for which thermal maturity has been documented, the Qingjiang biota is the least thermally mature, and therefore holds promise for enriching our understanding of BST deposits. [ABSTRACT FROM AUTHOR]

The axial Arcabuco-Floresta segment of the Eastern Cordillera basin, Colombia exhibits a complex geological history characterized by both along and across strike variations in deformation and exhumation, as well as magmatic activity, all of which provide valuable insights into the broader tectono-thermal evolution of the Andean region. In this study, we combine existing thermochronological data, with 16 new zircons (U-Th)/He and 9 new fission-track dates, and numerical modeling to investigate the thermal history in response to such anomalies across the axial Arcabuco-Floresta segment. Single grain ZHe data from Devonian to Lower Cretaceous strata range from 74 to 20 Ma. ZFT data from the same samples show a broader age distribution ranging from 200 to 70 Ma. The integration of different inverse modeling approaches suggests that cooling, here interpreted as exhumation, occurred in three distinct episodes which can each be linked to different regional tectonic interactions since the Late Cretaceous. Over this time, exhumation commenced in the northern and western parts of the basin and extended progressively through to the eastern and southern parts. The first episode, from the Late Cretaceous to Eocene is related to the accretion of different oceanic terranes related to Farallon Plate. The second, from the Oligocene to Middle Miocene, is interpreted as a probable compressional response to accretion of the Panamá-Chocó Arc, Nazca Plate and the Gorgona Terrane. The third, extending from the Middle Miocene to Pleistocene, may be associated with exhumation driven by far-field deformation resulting from the final collision phase of the Panamá-Chocó block with South America and its interaction with the Nazca and Caribbean plates. This last phase led to the complete emergence of the Eastern Cordillera and its development as an orographic barrier. No evidence was found suggesting any possible influence of thermal overprinting on the thermochronological data in the basin.

The pre-Jurassic in the north depression of the Tuha depression is the most favorable replacement strata to obtain new reserves in the Turpan–Hami Basin. (Pre-Jurassic, in this paper, refers to the Permian and Triassic.) The main source rocks are the Taodonggou Group, of which the burial history and hydrocarbon generation potential remain unconfirmed. The investigation of the burial and thermal history is vital for the basin analysis and hydrocarbon exploration. Therefore, in this paper, by using the acoustic time difference method, vitrinite reflectance method, stratigraphic trend method and PetroMod-1D software, the differential characteristics of denudation thickness, burial history and thermal evolution history of different tectonic units in different periods of Taibei Sag in the Turpan–Hami basin are studied, and their influence on the petroleum system is analyzed, and then the zones with exploration potential are optimized. The results show that the Taibei Sag has experienced multiple tectonic uplift events. The Late Indosinian movement has profound effects on the Taodonggou Group source rocks. The rather large uplift amplitude postpones the maturation of source rocks. In addition, the Turpan–Hami Basin is a typical cold basin. Therefore, the thermal maturity of the source rocks is relatively low, with respect to the relatively deep burial. The thermal histories of the different sub-sags in the study area are slightly differentiated from each other. The Taodonggou Group source rocks in the Taibei Sag generally became mature during the Mid–Late Jurassic epoch, except for those in the Central–Southern Shanbei sub-sag, represented by Well LT-1, which reached the mature stage during the Late Triassic epoch. The study area has well-developed reservoir rocks, and effective reservoir bodies are formed in the slope zone and near the Tainan Sag, due to the higher porosity and permeability of reservoir rocks. The statistics related to the faults and an analysis of the structural styles of oil reservoirs indicate that the structural slope and anticline of the Huobei, Lianbei and Shanbei sub-sags are favorable for increasing reserves and production of hydrocarbons. [ABSTRACT FROM AUTHOR]

Rock–Eval Pyrolysis, vitrinite reflectance and 1D basin modelling were used at four well locations within the Rawat Central sub-basin to model the burial and thermal history, which involves temperature changes over time, to understand the processes of hydrocarbon generation and expulsion. The accuracy of the model was ensured by calibrating it using vitrinite reflectance data. The TOC/Rock–Eval data reveal that the dominant kerogen type in Galhak source rock is a mature type-II and type-III kerogen. Very few samples show a highly pyrolyzate-yielding early to peak mature (0.6–0.82%Ro) type-I kerogen, ranging from a good source class to an excellent source capable of generating oil in Wateesh-1 and Rawat C-1 wells. In contrast, low pyrolyzate-yielding kerogen type, type-II/III, was indicated in Shawa-1, Mugud-1 and Rawat SE-1 wells, capable of generating oil and gas and type-IV which is completely inert. The Ro% gradient for Wateesh-1 and Rawat C-1 wells revealed that the oil window in Wateesh-1 and Rawat-1 wells start at depths around (1800 m) and (2160 m), respectively. Lower, Middle Galhak and Galhak shale entered the oil window during the Eocene (46–58 Ma) at the deeper locations (Wateesh-1), while generation started during the Oligocene (32.16–30.04 Ma). Expulsion starts during the Late Oligocene (⁓26 Ma). In contrast, towards the basins' margin (Shawa-1 and Mugud-1), Lower, Middle Galhak and Galhak shale reached the oil window in Oligocene–Miocene (32–6.49 Ma), and the generation starts late during the Oligocene-Pliocene (30.71–4.34 Ma). The broad age range observed in the wells can be attributed to their location on the flank of the basin, where achieving optimal depth necessitates an extended maturation period. Generation (TR > 10%) in Melut was only initiated in Wateesh-1 and Shawa-1 during (Miocene-Pliocene), while Adar has not reached the generation stage. Most of the HC was generated from the lower Galhak source rock in the depocenter which is not penetrated by the study wells. This can be attributed to the increase in maturity with depth in Lower Galhak compared with the shallower mid-Galhak and Galhak Shale source rock layers, which generated less quantities even though they have higher values of TOC%. [ABSTRACT FROM AUTHOR]

Copyright of Special Oil & Gas Reservoirs is the property of Special Oil & Gas Reservoirs Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective Commercial oil accumulation in the Jinghe Oilfield of the Southwest Ordos Basin was primarily found in the Northeast area. Previous studies have shown that oil mainly sourced from the oil shale in Member 7 of the Yanchang Formation. However, whether the oil comes from the source rocks spatially located in the Jinghe Oilfield or the basin center has not been determined, which inhibits further exploration of the Jinghe Oilfield. Methods In this paper, the hydrocarbon generation and expulsion history of source rocks in Member 7 of the Yanchang Formation in different tectonic parts of the Jinghe Oilfield and in the basin center have been reconstructed through basin simulation. Then, the accumulation periods of oil in the Yanchang Formation reservoir have been identified using fluid inclusion technology. Results The time window comparison of the oil accumulation in reservoir and the hydrocarbon generation and expulsion of source rocks show that oil in the Jinghe Oilfield limitedly came from the source rocks beneath the Jinghe Oilfield but more widely came from source rocks in the basin center. The oil in the Jinghe Oilfield generally shows the migration direction from Northeast to Southwest. Conclusion Therefore, unlike the traditional model of short-distance vertical migration, a new model can be established as that, the oil in the Jinghe Oilfield mainly laterally migrated from the hydrocarbon kitchen in the basin center along the strike-slip fault belt. The research results can provide an important reference for the prediction of hydrocarbon accumulation zones in the Jinghe Oilfield.

The clumped isotope paleo-thermometer has become a valuable proxy for the burial history reconstruction of carbonate formations. To maximise the accuracy of these reconstructions, post-depositional alterations, such as recrystallisation and Δ47 isotope exchange reactions, must be understood. In this study, we examine the isotopic behaviour of calcites and early dolomite samples from the same stratigraphic intervals, and thus with similar burial history. This approach provides additional constraints on the kinetics of Δ47 reordering in dolomite during exhumation. Clumped isotope measurements were performed on 19 calcites and 15 early dolomites from the Permian, Jurassic, and Cretaceous periods from four locations in Oman spanning different burial regimes. The calcite and dolomite samples were collected from the rock matrix, based on the assumption that fine material was more susceptible to recrystallisation. Our results show that calcites and dolomites record different Δ47 values despite being subjected to the same thermal history. The maximum Δ47 temperature recorded in dolomites (181 ± 13 °C) corresponds to the oldest and most deeply buried Permian rock. This value is approximately 35 °C higher than those measured in the co-located and coeval calcite matrix (145 ± 14 °C). This discrepancy suggests that calcite and dolomite have different kinetic parameters. Our data confirm (1) that dolomite Δ47 values are more resistant to alteration during burial and exhumation than Δ47 calcite values, and (2) that dolomite has a higher Δ47 closing temperature than calcite during cooling. The presence of two mineral phases with distinct kinetic parameters in the same stratigraphic unit provides additional constraints on models of burial and uplift. In addition, mineralogical data coupled with Δ47 and burial depths suggest that the progressive development of dolomite cation ordering is driven by temperature elevation, as previously suggested. [ABSTRACT FROM AUTHOR]

The main aim of the study is to reveal burial history, thermal maturity and timing of petroleum generation of source rock bearing formations mainly Urandab Shale within Ogaden Basin. A study was carried out using collected core samples from wells Elkuran-1, Hilala-1, Shillabo-1, and Shillabo-2. Combinations of burial histories, geochemical analyses were used to characterize the potential source rocks and hydrocarbons generation of Lower Triassic to Upper Cretaceous Formations. Burial history showed that rapid sedimentation took place during the Jurassic-Cretaceous. Thermal modeling revealed that the obtained organic matter maturity is in the initial phase of the early oil window which is connected with subsidence due to rapid sedimentation during the Middle Jurassic to Lower Cretaceous. The amount of generated hydrocarbon is fairly good. The generated hydrocarbons are expected to be expelled from Urandab Source Rock. Overall ranking of burial-history locations in order of decreasing thermal maturity is Shilabo-1 > Hilala-1 > Elkuran-1 > Shilabo-2. Average maturation depths and hydrocarbon generative potential for Urandab Shale are as follows: Early oil at 1200 m in Elkuran-1 well, Early oil at 14,500 m and Main oil at 1750 m in Hilala-1 well, Early oil 1200 m and Main oil at 1700 m, in Shilabo-1 well and Early oil at 1100 m and Main oil at 1600 m, in Shilabo-2 well. The results indicated that gas and late oil were generated in older source intervals while good oil-prone source rocks which produce early and main oil occurred particularly in Urandab Source rock and peak petroleum generation for Urandab Shale started during the Lower Jurassic. [ABSTRACT FROM AUTHOR]

The Moche archaeological culture flourished along Peru's North Coast between the 4th and 10th centuries CE and was characterized by a complex social hierarchy dominated by political and religious elites. Previous archaeological evidence suggests kinship was a key factor in maintaining political authority within Moche society. To test this hypothesis, we applied archaeological, genetic, and isotopic methods to examine familial relationships between six individuals, including the prominent Señora de Cao ( ~500 CE ), buried together in a pyramid-like, painted temple, Huaca Cao Viejo, in the Chicama Valley, Peru. Our findings reveal that all six individuals were biologically related, with varying degrees of kinship. The Señora de Cao was interred with a sacrificed juvenile, identified as a possible niece, and at least one, and potentially two siblings and a grandparent in separate tombs nearby. One of the male siblings was accompanied in death by his sacrificed son. Isotopic analysis indicates that while most individuals had diets rich in maize and animal protein and spent their childhoods in or near the Chicama Valley, the sacrificed juvenile accompanying the Señora had a distinct diet and geographic origin. These results demonstrate that Moche elites were interred with family members, including some raised far from their parental homes. This supports the hypothesis that kinship was central to transmitting status and authority. Moreover, sacrificing family members to accompany deceased elites underscores the significance of ritual sacrifice in reinforcing familial ties and linking the deceased to both ancestors and the divine., Competing Interests: Competing interests statement:The authors declare no competing interest.

Objectives: Burial space reuse and prolonged interaction with the dead were common practices in the Isthmo-Colombian Area, dating back to at least the Early Ceramic Period in the Greater Coclé region. However, biological and social relationships of individuals interred in collective burial contexts remain unclear. Here, we explore intra-cemetery biological variation through a biological distance analysis of individuals interred in large mortuary features from the first mortuary horizon at the site of Cerro Juan Díaz in Panamá., Materials and Methods: Individuals recovered from Features 2, 16, and 94 from Operation 3 at Cerro Juan Díaz were assessed for dental metric and nonmetric traits. Biological distances were calculated through Gower coefficients and subsequently assessed visually with PCoA plots. Differences in phenotypic variability within burial feature (n = 26), age (postpubescent individuals aged 15+ years vs. prepubescent individuals; n = 27), and sex (n = 14) groupings were evaluated statistically via permutational multivariate analysis of variance (PERMANOVA) and PERMDISP tests., Results: The estimated distances for each individual showed broad similarities between the three burial features. Significant differences in biological distance were found only when comparing by age. Gower coefficients for prepubescent individuals differed from those of postpubescent individuals in terms of both group centroid location and data point dispersion around centroids., Discussion: Our results are largely consistent with previous notions of Cerro Juan Díaz's function as a community burial ground. Prepubescent individuals may have been brought to the site for burial from nearby villages, perhaps following specific mortuary traditions governed by age group., (© 2024 The Author(s). American Journal of Biological Anthropology published by Wiley Periodicals LLC.)

Female burials equipped with weapons, a topic of interest among scholars and the general public, remain rare occurrences in archaeological records. The interpretation of such cases requires an interdisciplinary approach and a comprehensive evaluation of the available evidence, particularly regarding the sex and potential lifestyle of the deceased. Consequently, data on specific populations, regions, and time periods remain scarce. For instance, no such case has been reported before concerning the 10th century CE of the Carpathian Basin, known as the Hungarian Conquest period. Our study focuses on an interdisciplinary investigation of a previously known burial, grave No. 63 from the 10th-century-CE cemetery of Sárrétudvari-Hízóföld (eastern Hungary), which represents a unique case with grave goods including jewelry typically associated with females and archery equipment traditionally linked to males. Through archeological, anthropological, and archaeogenetic analyses, we aim to determine if this case represents the first-known female burial with weapon from the 10th-century-CE Carpathian Basin. Despite the poor bone preservation, a factor limiting data recording and evaluation, all analyses consistently indicate that the skeletal remains belonged to a female individual. The burial customs, including weapon equipment composition show analogies with male counterparts in the series. In addition, the pattern of pathological and supposed activity-related changes observed on the bones may have resulted from regular physical activity during her lifetime. In summary, our findings support the identification of this case as the first known female burial with weapon from the 10th-century-CE Carpathian Basin., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Tihanyi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

While medieval and modern embalming practices in Western Europe are attested to historically and bioarcheologically, especially for famous historical figures, there are few recorded occurrences of this type of corpse preparation for a large number of archaeological individuals from the same lineage. Moreover, evidence of such practices mainly concerns adult individuals, whereas traces of child embalming are extremely rare. In 2017, the discovery of a crypt in the chapel of the Château des Milandes (Castelnaud-la-Chapelle, Dordogne, France) revealed a collective burial of the scattered remains of seven adults and five children of the aristocratic Caumont family, who died in the 16th and 17th centuries and whose skeletons all show marks of embalming practices. In 2021, another excavation in the chapel uncovered the individual grave of an elderly woman whose body was also embalmed. This skeletal sample provides a unique opportunity to examine the modus operandi of medieval embalming through the cutmarks left on the cranium and appendicular skeleton and to compare mortuary protocols for adults and children. Our macroscopic and microscopic investigations revealed a thorough and highly standardized technical treatment that was similar for both adult and very young immature individuals and displays a skillset that was passed down over two centuries., Competing Interests: Declarations Ethics statement The research was conducted in accordance with all French ethical and legal guidelines for the excavation, handling, and analysis of archaeological human remains. The remains were handled with care to minimize disturbance and preserve their integrity for future research, with some remains being partially reburied in situ. Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

Geochemical and lithological investigations in the WON C-3X well record five organic-matter-rich intervals (OMRIs) of effective source rocks. These OMRIs correspond to moderate and good potentials. Two of these intervals occurred within the L-Kharita member of the Albian age represent 60.97% of the entire Albian thickness. The rest of OMRIs belongs to the Abu-Roash G and F members of the Late Cenomanian–Santonian age comprising 17.52 and 78.66% of their total thickness, respectively. The calculated heat flow of the studied basin is high within the range of 90.1–95.55 mW/m2 from shallower Abu-Roash F to deeper L-Kharita members. This high-heat flow is efficient for shallowing in the maximum threshold expulsion depth in the studied well to 2,000 m and active source rock depth limit to 2,750 m. Thermal maturity and burial history show that the source rock of L-Kharita entered the oil generation from 97 Ma till the late oil stage of 7.5 Ma, whereas the younger Abu-Roash G and F members have entered oil generation since 56 Ma and not reached peak oil yet. Hence, the source rock intervals from Abu-Roash F and G are promising for adequate oil generation.

Based on the results from the previous research on Mesozoic igneous rocks, as well as tectonic environments in the northern South China Sea and southern East China Sea (NSCS-SECS), geophysical parameters, strata, and characteristics of seismic facies in NSCS-SECS were investigated. These findings were combined with results from the analysis of the balanced profile evolution to re-evaluate the tectonic evolution of SECS since the Jurassic. Furthermore, burial history and simulation of wells in the SECS were analyzed using well, seismic and source rock data. Furthermore, favorable models of oil–gas accumulation in the Lower–Middle Jurassic were proposed in combination with studies on elements and conditions of the petroleum system. The results demonstrated that the NSCS-SECS had consistent tectonic settings and comparable strata from the Jurassic to the Cretaceous time. There was a large unified basin in this period. The basin experienced two evolutionary stages, respectively, the fore-arc depression basin in the Early–Middle Jurassic (J1-2) and the back-arc faulted basin in the Late Jurassic–Cretaceous (J3-K). There was considerable deposition of dark mudstones in the SECS during the Lower–Middle Jurassic. The Keelung Sag was the depositional center accumulating the thickest section of the Lower–Middle Jurassic source rocks which entered a high-maturity stage. Hence, it was the hydrocarbon generation center in the SECS. The process of generating hydrocarbons from Lower–Middle Jurassic source rocks was of high complexity from northwest to southeast. The Lower–Middle Jurassic source rock at the northwest edges of the basin experienced two hydrocarbon generation stages, while the Keelung Sag toward the southeast experienced three hydrocarbon generation stages. The models and types of oil–gas accumulation in various evolutionary phases were different due to the control by tectonic evolution. Oil and gas that were generated by Lower–Middle Jurassic source rocks in the Keelung Sag migrated and accumulated in the western high-tectonic units. Research findings provide insights into Mesozoic oil and gas exploration in the NSCS-SECS.

Nineteen ditch samples and rock–eval pyrolysis data taken from Wakar-1 well of Wakar Field and PFM-SE-1 well of Port-Fouad-Marine Field selected for petrographic, elemental, total organic carbon (TOC), and geochemical analyses of the Oligocene-Pliocene mud rich formations (Fms). They differentiate in studied wells from base to top into Tineh Fm (Oligocene), Qantara Fm (Lower Miocene), Sidi Salem Fm (Middle Miocene), Wakar Fm (Upper Miocene), Rosetta Fm (Upper Miocene), and Kafr El-Sheikh Fm (Pliocene). Petrographic analysis of Kafr El-Sheik samples shows that vitrinite is very common (52.03%), inertinite is common (42.74%), and liptinite is rare (5.32%). The same samples reveal a depositional setting within the shelf of proximal and distal depositional settings of suboxic-anoxic and dyoxic-oxic conditions. TOC, S1, S2, and production index (PI) of the studied formations show a poor to a fair quantity of OM. All the formations are dominated by terrestrial type III kerogen of mainly poor gas-prone potential. The maximum threshold of the relative hydrocarbon potential (RHP) curve is recorded at depths of 2600 m and 4650 m in Wakar well and shallowing to be at 1500 m and 3300 m in PEM-SE-1 well of either biogenic and thermogenic hydrocarbon (HC) generated peaks. The heat flow calculated in the present wells shows a gradual increase from 74.34mW/m2 (Wakar-1) to 80.93mW/m2 (PFM-SE-1) from the NW to SE direction. A sedimentary/subsidence (SED/SUB) ratio of value < 1 contemporary to the deposition of Tineh, Sidi Salem, and Kafr El-Sheikh Formations considers being due to either shallowing of the depositional basin and/or considerable tectonic activity in contrast to the rest of formations of SED/SUB ratio > 1. The burial history diagram of the Wakar-1 well reveals that the Oligocene to Upper Miocene Formations of Tineh, Qantara, Sidi Salem, and Wakar are entering the early oil generation stage since 3.4 Ma and have not proceeded to the peak stage of oil generation yet with a slight increase in maturity toward the SE direction. [ABSTRACT FROM AUTHOR]

The West Kalabsha (WKAL) area is a western extreme exploratory area of the Faghur Basin in the Western Desert of Egypt. The study of four wells (WKAL; A-1 X, K-1 X, P-1X, and C-1 X), interpreted with twenty seismic lines, shows that the area is dissected by a series of normal faults with an irregular, E–W strike direction. The general trend of the throw is toward the south–southeast. The most prospective area for hydrocarbon (HC) migration is toward the north (upthrown side) of an E-W striking normal fault north of the WKAl-K-1 X and A-1 X wells. The WKAL-P-1 X and WKAL-K-1 X wells in the Faghur Basin were selected for both geochemical evaluation of possible source rock intervals and burial history modelling within the basin. Integration of the wire-line logs with geochemical analysis identified six organic matter-rich intervals (OMRIs) within the Middle Jurassic-Lower Cretaceous sequence. Four intervals are in the Alam El-Bueib-3C (AEB-3C) member with a cumulative vertical thickness of 530ft. The other OMRIs are 110ft in thickness recorded within the AEB-6 (10ft) and Upper Safa (100ft) members. The studied organic matter (OM) reveals type III, IIIC, and IV kerogens (mainly gas-prone) with a terrestrial origin. They have reached a maturity level consistent with the late oil window. The expulsion threshold depth detected in the WKAL-P-1 X well is 12000ft in the AEB-3C member, whereas the active source depth limit (ASDL) is 15000ft in the Safa Member. The present study suggests a paleo-geothermal gradient range between 1.13oF/100ft and 1.39oF/100ft with an estimated regional erosion of 5500 to 7000ft of strata mainly between the Paleozoic-Jurassic and Cretaceous-Tertiary boundaries. The present-day geothermal gradient based on bottom-hole temperatures shows a geothermal gradient of 1.4oF/100ft (WKAL-P-1 X), that increases to the north to 1.65oF/100ft (WKAL-K-1 X). Burial history modelling reveals that sedimentary strata entered the mature oil zone in the Early Cretaceous (110–115Ma) at depths of 7500–8000ft in the deepest part of WKAL-P-1 X and WKAL-K-1 X wells (Paleozoic strata). Maturation continued to present, resulting in Jurassic and Lower Cretaceous strata currently falling into the late oil window. [ABSTRACT FROM AUTHOR]

The Dongpu depression, like other depressions in the Bohai Bay Basin, is characterized by overpressure, however, the published studies have not clearly given the overpressure formation mechanism and paleo-pressure evolution history in the Dongpu depression. In addition, the current researches are mainly focused on the northern Dongpu depression, while rare investigation has been conducted in the southern part. In this context, it is urgent to explore the comprehensive overpressure evolution and formation mechanism in the Dongpu depression in academic and industrial fields. This paper provided a systematic analysis of fluid inclusions, including fluid inclusion petrography, microthermometry, vapor phase filling degree measurement and PVT-x modeling. By using homogenization temperature-burial history projection, the trapping time of the oil inclusions are determined. Four pressure evolution stages are identified in both the northern and the southern Dongpu depression. The results indicate that the pressure accumulation stage is derived by disequilibrium compaction and hydrocarbon generation in the northern part because of the salt rock distribution, while the stage is only derived by hydrocarbon generation in the southern part because of no salt rock distribution. The pressure release stages are mainly caused by the tectonic uplifting movements at the end of Dongying and Minghuazhen Formation. The overpressure in most areas in the northern part has been preserved till now, which is considered as a result of the good plasticity and sealing ability of salt rock that prevent the pressure leakage by smearing on the fault. Areas without salt rock distribution show normal pressure, which means the salt rock is an important factor that contributes to the overpressure preservation. However, there are exceptions that in Baimiao and Qiaokou, the overpressure still exists even without salt rock distribution, which is due to fault closure. [ABSTRACT FROM AUTHOR]

Igneous intrusions induce alterations in coal and minerals. Alteration degree depends upon the in-situ coal rank and maceral composition, the intrusion temperature, heat source proximity, and intrusion size. In the Permo-Carboniferous Fengfeng coalfield, coal rank increases over some 50 km distance south to north from high volatile bituminous coal to anthracite. The coal seams were commonly intruded, and the regional elevation of rank was augmented by Jurassic-Cretaceous igneous intrusions, not just burial coalification. The petrographic examination of a semianthracite from the Dashucun mine in the north of the Fengfeng coalfield shows development of coke microstructure and increased reflectance approaching the dike in the No. 2 Seam. Based on 11 samples at 50-cm horizontal intervals, random vitrinite reflectance value (R r) declines from 5.41% at the contact to the background value of 2.05% at 5-m distance from the contact. Towards the dike, vitrinite anisotropy increases and the microtexture shows development of circular, coarse mosaic, and ribbon anisotropic coke textures and devolatilization vacuoles. Natural coke textures respond to an estimated temperature > 570 °C at the intrusion/coal contact. However, the occurrence of coke structures within a semianthracite reveals a local and regional thermal evolution. Coke textures suggest that coal rank was high volatile A bituminous coal at the time of intrusion. This has implications for burial history, heating, and subsidence rates. Assuming a paleogeothermal gradient of 40 °C/km, high volatile A bituminous coal (1% R r) would have been buried to 3 km at the time of the Jurassic intrusion. The intrusion metamorphosed high volatile bituminous coal to natural coke and subsequent larger-scale regional metamorphism then metamorphosed the coal to semianthracite. [ABSTRACT FROM AUTHOR]

The Cenomanian Mishrif Formation is one of the most important carbonate reservoirs in the Mesopotamian Basin. Detailed petrographic analysis, aided by geochemistry and burial history establishment on Mishrif carbonates from the AD oilfield, located at the margins of the Central Mesopotamian Basin of Iraq, presents a distinctive differential diagenetic mechanism that significantly impacts reservoir quality and exhibits a pronounced relationship with tectonic evolution and hydrocarbon accumulation. Analyses of petrographic features, carbon‑oxygen isotopes, and minor and rare-earth elements reveal that echinoderm shells and rim calcites are results of marine waters; sparry calcites, matrix, and vein calcites from host rock primarily precipitate from meteoric fluid; microspars and vein calcites in the concretionary limestone are derived from brine water. The development of concretionary limestone mainly involves a complex process that comprises extensive bioturbation in marine waters, substantial fabric-selective dissolution in the meteoric zone, and significant sparry calcites occluded dissolved spaces in shallow burial environments. Winding and skew seams of argillaceous sediment around concretionary limestones, as well as the excellent preservation of skeletal remains inside the concretionary zone, manifest that the development of the concretionary limestone accomplished during the early diagenesis stage and pre-compaction. These centimeter-to-decimeter scaled concretionary limestones intermixed with host rock holding abundant open porosities shape the Mishrif reservoir and result in an inconspicuous, dual permeability system. The burial history, integrated with the diagenetic sequence and tectonic evolution, elucidates four stages that clarify interactions of diagenesis, porosity preservation, and hydrocarbon accumulation. The Cenomanian to Turonian period was a critical stage for the development of effective reservoir capacity. The end of the Cretaceous, marked by the contraction of the Neo-Tethys and the complete closure of the South Neo-Tethys, witnessed an early hydrocarbon accumulation event that enhanced reservoir porosity preservation. During the Paleocene to the Early Miocene epoch, the Neo-Tethys tended to be closing. As a result, the Mishrif Formation experienced shallow burial and generated typical concretionary limestone, which provided a rigid framework against compaction. From the Early Miocene to the present, the total closure of the Neo-Tethys and the Zagros Orogeny initiated a significant late oil-filling event that acted as the main accumulation moment, coinciding with efficient trap development and other optimal petroleum conditions. This study contributes to (1) comprehending the genesis of the differential diagenesis and its effect on pore structures and reservoir heterogeneity, and (2) linking diagenetic sequence to tectonic evolution and hydrocarbon accumulation of foreland basins evolved from Neo-Tethys tectonics. Clumped isotopes are first introduced to constrain the burial history. Mishirif Formation has experienced four diagenetic stages. Three cemented processes determine the origin of the differential diagenesis. Four stages are divided involving diagenesis, oil-filling, and tectonics. [ABSTRACT FROM AUTHOR]

Radish concretions exhibit a typical columnar to pear‐shaped, stipe downward geometry. In Middle Jurassic mudrock in south‐west Germany, radish concretions started to form around an iron‐sulphide lined tube by pervasive cementation constituting an ellipsoidal parent domain in uncompacted sediment at burial depths of ≤5 to 8 m as recorded by 75 to 80% minus‐cement porosity. Thereafter, the concretions grew vertically in compacting sediment as evidenced by laminae within the concretions being increasingly inclined towards the tips, and concomitantly decreasing minus‐cement porosity. During early diagenesis, prior to septarian crack formation, bicarbonate generating the microbial cement originated within the sulphate reduction zone chiefly from anaerobic oxidation of methane and to a lesser degree of organoclastic material. Later, at 50 to 70 m burial depth, septarian cracks formed as evaluated by sedimentation–compaction analysis based on minus‐cement porosity data and compressibility of similarly composed sediments. The outward‐narrowing septarian cracks indicate that they formed when the concretions were still in a plastic state but already cemented sufficiently to be resistant against compaction. In this stage, up to one‐quarter of the pore volume of the concretions was still open as suggested by shrinkage experiments. This pore volume, and the septarian cracks, were filled with cement termed late diagenetic. In the study area, the decompacted net‐sedimentation rate was low, about 2 to 3 cm kyr−1, for ca 2.5 Myr, allowing the concretions to reside for a long time within the sulphate reduction zone and to grow. Radish concretions formed within the transition zone from thick, rapidly deposited to long‐term, slowly accumulating sediment. [ABSTRACT FROM AUTHOR]

The Middle–Late Jurassic Sargelu, Naokelekan, and Barsarin formations of northwestern Iraq have been investigated in the Shaikhan oilfield (well Shaikhan-8) to assess their potential for hydrocarbon generation.The results of total organic carbon analysis and rock-eval pyrolysis revealed a good-to-excellent hydrocarbon content and suggest that the depositional conditions were suitable for the production and preservation of organic matter. The thermal maturity proxy indicates that the studied formations were at the start of the hydrocarbon generation period. Most of the samples from the Sargelu and Barsarin formations belong to kerogen type II, whereas those of the Naokelekan Formation belong to kerogen type II/III. The Pr/Ph, Pr/n-C17, and Ph/n-C18 ratios of the extracted bitumen indicated that the organic matter originated from marine sources under reducing conditions. The stable carbon isotope composition of the saturated and aromatic hydrocarbon fractions ranged from –28.3 to –27.7 ‰ and –28.0 to –27.7 ‰, respectively. The biomarker results show a high contribution of marine organic matter that was preserved under relatively anoxic conditions. The profiles of the burial and thermal maturity history show that the simulated generation zones, based on the calculated vitrinite reflectance, indicate immature (0.44%–0.6%)-to-early oil generating (0.6%–0.75%) source rock. The low thermal maturity of the studied formations relative to the depth may be attributed to the low geothermal gradient and heat flow.

A karst fracture-cavity was developed in the Ordovician Yingshan Formation in the northern slope of the Tarim Basin center area (Tazhong area); however, the area experienced multistage karst and diagenesis in the later period, and the reservoir was heavily reformed, characterized by complex distribution. Based on the testing of the inclusions in the karst fractures and fracture-cave calcite, this study summarizes the physical and chemical characteristics of the inclusions in the northern slope of Tazhong. The major inclusions were liquid and gas–liquid phases, while the minor ones were hydrocarbon phases. Based on the salinity–homogenization temperature diagram, the gas–liquid inclusions could be divided into seven types: low-temperature low-salinity inclusions (the lowest salinity was 0.88%, which is lower than that of present sea water; the lowest temperature of the inclusions was 49°C); low-temperature high-salinity inclusions; medium-temperature low-salinity inclusions; medium-temperature medium-salinity inclusions; medium-temperature high-salinity inclusions; high-temperature medium-salinity inclusions; and high-temperature high-salinity inclusions. The development of inclusions was characterized by high temperature and high salinity or low temperature and low salinity. In addition, the low-temperature and low-salinity inclusions near the unconformity surface were well-developed. The high-temperature and higher-salinity inclusions far from the unconformity surface were also well-developed. A burial history analysis showed three stages of karstification or filling in the area: exposed karstification in the Middle Caledonian, shallow burial filling in the Middle Hercynian, and burial filling in the Late Hercynian. By determining the inclusions in calcite associated with mud in the karst caves and combined with previous studies, the Middle Caledonian was found to be the period associated with the eogenetic karstification of meteoric water and seawater. This is the key factor in the formation of karst reservoirs in the Tazhong area. The large-scale calcite growth in the Middle Hercynian and Late Hercynian burial periods led to further filling of the early karst reservoir, reduced reservoir space, and enhanced reservoir heterogeneity.

This study reports on the bioarchaeology and evidence of interpersonal violence in a group of archaeological skeletons found near Ladismith, Western Cape, South Africa. The co-mingled skeletal remains derive from at least ten individuals of varying ages and both sexes. Overlapping radiocarbon dates on three individuals place them in the first half of the 15th century CE, pre-dating first European contact at the end of that century. Three juvenile crania have perimortem perforations, the locations of which indicate violent deaths. The sizes and shapes of the lesions suggest impact by a blade at least 110mm long and 50mm wide but with edges only 2mm thick. Based on these dimensions, we hypothesise that this was a metal-tipped spear. The nearest metal-working communities at this time lived approximately 500 km away, implying long-distance trade or exchange. δ13C, δ15N and 87Sr/86Sr values indicate that this was a heterogenous group of individuals who had spent their early lives in different locations and consumed varied diets, who had come together and were living in or travelling through the Ladismith area at the time of their deaths. This finding extends the timeframe and location for the practice of communal burial in the Holocene of southern Africa and provides additional support for the hypothesis that communal burials in this region tend to be associated with violence., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Mole et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Pottery vessels often comprise major burial goods at archaeological sites, thus providing valuable information for reconstructing past mortuary practices. However, because of the uncertainty of its function or use, which has been interpreted mostly through typological studies alone, the analytical potential of pottery as a burial good has not been fully exploited. This study applied bio-chemical and geochemical analyses for the first time to funerary pottery vessels of the Iron Age of North Iran to examine their function and use. The study materials are from the necropolis of Ghalekuti, Dailaman, excavated in the 1960s. Direct radiocarbon dating conducted on human and animal bones in the graves and typological analysis of the pottery anchored the chronological position of the pottery materials to the 2nd and 1st millennium BC. A petrographic analysis revealed that pottery vessels can be classified into six fabric types, including those with coarse tempers that are effective for cooking. Pottery pastes with finer inclusions less suited for cooking appeared during the early first millennium BC (Iron Age III). To obtain further insight into the function of the pottery, we conducted organic residue analyses. The results demonstrated that the vessels retained remains of botanical and animal origin. In particular, jars with tubular spouts, characteristic of the Iron Age III period, were likely specialised for botanical products. Interestingly, both carcass and dairy products from ruminant animals (cattle and caprine) were processed in short-neck jars and bowls, including spouted bowls, suggesting their use in a liquid state. Products from ruminants, particularly dairy products, may have played a significant role in the daily and ritual use of pottery vessels during the study period in Northern Iran. These results indicate that a range of pottery vessels used for specific purposes before the burial was offered for graves, helping us better understand the mortuary practices of Iron Age Iran., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Casanova et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Maspalomas is one of the most important archaeological sites in Gran Canaria, Canary Islands. The necropolis is one of the few funerary sites on the island where several the skeletons were found in anatomical position. The burials correspond to graves and cists dated between the 12 th and 15 th century CE. These graves and cists are clustered together in different formations across the necropolis, giving rise to a complex composition that denotes the existence of possible interpersonal relationships of the people buried there. A total of 135 calcanei and 118 tali were analysed to find non-metric traits and to test whether the clustered burials share a non-metric trait relationship. Trait combinations were formed using talus and calcaneus non-metric traits separately. The results of this study suggest that the individuals of Maspalomas showed a very high prevalence of lateral and medial talar facets, attributed to prolonged squatting position and/or walking on uneven ground. The calcaneal facet pattern (that may be aetiologically genetic) is more closely related to that observed among North-Africans or Indians than to Western Europeans. Calcaneal facet type Ib, and other genetically-determined traits, such as the extra facet extension of Posterior Facet, or the medial root of the inferior extensor retinaculum trait, either as single traits or as the combination of both traits, were significantly associated with individuals buried in different geographical areas of the necropolis defined by differences in burial structures, a finding that may suggest that genetically-linked individuals were buried in a separate area of the necropolis. The use of trait combination analysis in this study shows that the method can be applied to identify relationships among genetically or professionally related individuals that were subjected to a different burial procedure by their contemporaries.

The Aven de la Boucle (Corconne, Gard, southern France) is a karst shaft used as a collective burial between 3600 and 2800 cal BCE. The site encompasses the skeletal remains of approximately 75 individuals comprising a large majority of adult individuals, represented by scattered and commingled remains. To date, few studies have explored the potential of ancient DNA to tackle the documentation of Neolithic collective burials, and the funerary selection rules within such structures remain largely debated. In this study, we combine genomic analysis of 37 individuals with archaeo-anthropological data and Bayesian modelling of radiocarbon dates. Through this multidisciplinary approach, we aim to characterize the identity of the deceased and their relationships, as well as untangle the genetic diversity and funerary dynamics of this community. Genomic results identify 76% of male Neolithic individuals, suggesting a marked sex-biased selection. Available data emphasize the importance of biological relatedness and a male-mediated transmission of social status, as the affiliation to a specific male-lineage appears as a preponderant selection factor. The genomic results argue in favour of 'continuous' deposits between 3600 and 2800 BCE, carried out by the same community, despite cultural changes reflected by the ceramic material.

The Leijia area in the Western Depression of the Liaohe River has good oil and gas exploration and development potential, but the current analysis of the burial history in this area lacks a clear understanding.This paper uses the recovery principle of subsidence history to restore the original thickness of the remaining stratum in the study area.Firstly, the sonic curve method and the adjacent layer comparison method are used to restore the denuded thickness of the stratum.Sandstone, argillaceous limestone, limestone mudstone, mudstone) were subjected to compaction simulation experiments, and the porosity-depth curve of the sample was obtained according to the experiment.Use the existing burial data to calculate the thickness of the stratum framework, and according to the constant volume formula of the framework, use each single lithological layer as the smallest unit to carry out the backstripping calculation one by one to obtain the sedimentary thickness of each group and section in different geological periods and the depth of burial.According to the analysis of burial history, during the burial process of the Cenozoic strata in Leijia area, the sedimentation rate of the Paleogene Shahejie Formation was higher and the sedimentary strata was thicker, but the second Member of Shahejie Formation was uplifted and eroded and the strata was thin; During the Dongying Formation, the stratum deposition slowed down, and the stratum was uplifted and eroded at the end; in the Neogene and Quaternary, the stratum deposition rate was low, and the thickness of the deposited stratum was not large.

We systematically incorporate burial history, sea floor geometry and tectonic loads from a sequential kinematic restoration model into a 2D evolutionary geomechanical model that simulates the formation of the Sandia salt diapir, Tarfaya basin, NW African Coast. We use a poro‐elastoplastic description for the sediment behaviour and a viscoplastic description for the salt. Sedimentation is coupled with salt flow and regional shortening to determine the sediment porosity and strength and to capture the interaction between salt and sediments. We find that temporal and spatial variation in sedimentation rate is a key control on the kinematic evolution of the salt system. Incorporation of sedimentation rates from the kinematic restoration at a location east of Sandia leads to a final geomechanical model geometry very similar to that observed in seismic reflection data. We also find that changes in the variation of shortening rates can significantly affect the present‐day stress state above salt. Overall, incorporating kinematic restoration data into evolutionary models provides insights into the key parameters that control the evolution of geologic systems. Furthermore, it enables more realistic evolutionary geomechanical models, which, in turn, provide insights into sediment stress and porosity. [ABSTRACT FROM AUTHOR]

The Huanghua Sag is located in the northern part of the Bohai Bay Basin and is a Mesozoic rift basin developed on the North China platform. Carboniferous source rocks are developed in the Huanghua Sag. The basin has experienced multiple stages of complex tectonics, and uneven uplifts and deformations have appeared in the basin. In addition, magma ejection is also developed in this area. The hydrocarbon generation evolution of the source rocks in the Huanghua Sag has the characteristics of discontinuity and grade differences. In this paper, based on the detailed study of structural history, we have conducted a systematic study on the burial history, heating history and hydrocarbon generation history of source rocks in the Huanghua Sag. At the same time, the EASY¾R, numerical simulation method was used for the apatite fission track (AFT) test and fluid inclusion analysis. The results show that the maturity of source rocks gradually develops with the generation of hydrocarbons. Combined with tectonic events, we discussed the intensity and time distribution of hydrocarbon generation of the source rocks. The hydrocarbon generation analysis of the source rock shows that the Huanghua Sag occurred continuous subsidence in the late Cenozoic. In the end, we proposed the co-production of Permian-Carboniferous unconventional natural gas in the centralnorthern area of the Huanghua Sag in the Bohai Bay Basin. [ABSTRACT FROM AUTHOR]

Despite their ubiquity, Mesolithic lithic tools given as funerary offerings have rarely been studied in detail. Whereas personal ornaments (e.g. beads, pendants) are commonly interpreted as markers of social identity and status, archaeologists have struggled to understand the stone tools, commonly regarded as "utilitarian" items. As a result, this class of grave goods has not received the same level of attention, leaving a significant gap in our understanding of Mesolithic mortuary behaviours. Our research challenges long-lasting perceptions of lithic tools as strictly utilitarian objects and draws on studies of one of the most substantial stone axe funerary collections from one of the largest Stone Age cemeteries in Europe-Zvejnieki, Latvia. Evidence suggests the selection of unused axes as grave offerings, while unusual wear traces on an axe found in a female grave (no 57) raises questions about its use in the burial rites. Using a multi-proxy approach, we compare life histories of axes placed in burials to those recovered from contemporary, nearby settlement contexts. Finally, a strong correlation between axes and women and children at Zvejnieki challenges gendered stereotypes of stone tools, historically regarded as possessions of the adult male members of Stone Age societies., (© 2024. The Author(s).)

The Merovingian period (5th to 8th cc AD) was a time of demographic, socioeconomic, cultural, and political realignment in Western Europe. Here, we report the whole-genome shotgun sequence data of 30 human skeletal remains from a coastal Late Merovingian site of Koksijde (675 to 750 AD), alongside 18 remains from two Early to Late Medieval sites in present-day Flanders, Belgium. We find two distinct ancestries, one shared with Early Medieval England and the Netherlands, while the other, minor component, reflecting likely continental Gaulish ancestry. Kinship analyses identified no large pedigrees characteristic to elite burials revealing instead a high modularity of distant relationships among individuals of the main ancestry group. In contrast, individuals with >90% Gaulish ancestry had no kinship links among sampled individuals. Evidence for population structure and major differences in the extent of Gaulish ancestry in the main group, including in a mother-daughter pair, suggests ongoing admixture in the community at the time of their burial. The isotopic and genetic evidence combined supports a model by which the burials, representing an established coastal nonelite community, had incorporated migrants from inland populations. The main group of burials at Koksijde shows an abundance of >5 cM long shared allelic intervals with the High Medieval site nearby, implying long-term continuity and suggesting that similarly to Britain, the Early Medieval ancestry shifts left a significant and long-lasting impact on the genetic makeup of the Flemish population. We find substantial allele frequency differences between the two ancestry groups in pigmentation and diet-associated variants, including those linked with lactase persistence, likely reflecting ancestry change rather than local adaptation., Competing Interests: Competing interests statement:The authors declare no competing interest.

The third millennium BCE was a pivotal period of profound cultural and genomic transformations in Europe associated with migrations from the Pontic-Caspian steppe, which shaped the ancestry patterns in the present-day European genome. We performed a high-resolution whole-genome analysis including haplotype phasing of seven individuals of a collective burial from ~2500 cal BCE and of a Bell Beaker individual from ~2300 cal BCE in the Paris Basin in France. The collective burial revealed the arrival in real time of steppe ancestry in France. We reconstructed the genome of an unsampled individual through its relatives' genomes, enabling us to shed light on the early-stage admixture patterns, dynamics, and propagation of steppe ancestry in Late Neolithic Europe. We identified two major Neolithic/steppe-related ancestry admixture pulses around 3000/2900 BCE and 2600 BCE. These pulses suggest different population expansion dynamics with striking links to the Corded Ware and Bell Beaker cultural complexes.

The Cortijo Coracho archaeological site dates from the Late Antiquity period, from the 5 th to the 8 th century AD. During this period, a number of populations settled in the area (Germanic peoples until Visigothic rule, Byzantine until the arrival of the Arabs, etc.), each of them concentrating the historical characteristics in the Sub-Baetic that are currently known. The Cortijo Coracho archaeological site is currently located in the city of Lucena (Cordoba, Spain), found after the works on the A-45 motorway. The necropolis consists of 294 inhumations and the remains of a basilica, although after a series of surveys it is estimated that there are around 700 additional burials, which would make it the largest necropolis with ad sancti burials surrounding a martyrial basilica dating back to the 4 th century AD. Among the burials, 397 subjects were recovered, which implies a large presence of shared and/or reused burials. These subjects were transferred to the city's museum, where they were examined, reorganised and classified. At this point, subjects of scientific interest were found, as is the case of subject 204, the topic of this article. This individual, described as an adult male, is an example of the living conditions of this period, since despite his injury on the left lower extremity, a double fracture aggravated by a chronic osteomyelitis infection, he continued to use that limb. This paper will give the details of that distinctive lesion and the possible hypotheses underlying it.

The ancient city of Chichén Itzá in Yucatán, Mexico, was one of the largest and most influential Maya settlements during the Late and Terminal Classic periods (AD 600-1000) and it remains one of the most intensively studied archaeological sites in Mesoamerica 1-4 . However, many questions about the social and cultural use of its ceremonial spaces, as well as its population's genetic ties to other Mesoamerican groups, remain unanswered 2 . Here we present genome-wide data obtained from 64 subadult individuals dating to around AD 500-900 that were found in a subterranean mass burial near the Sacred Cenote (sinkhole) in the ceremonial centre of Chichén Itzá. Genetic analyses showed that all analysed individuals were male and several individuals were closely related, including two pairs of monozygotic twins. Twins feature prominently in Mayan and broader Mesoamerican mythology, where they embody qualities of duality among deities and heroes 5 , but until now they had not been identified in ancient Mayan mortuary contexts. Genetic comparison to present-day people in the region shows genetic continuity with the ancient inhabitants of Chichén Itzá, except at certain genetic loci related to human immunity, including the human leukocyte antigen complex, suggesting signals of adaptation due to infectious diseases introduced to the region during the colonial period., (© 2024. The Author(s).)

This paper aims to re-examine the dietary practices of individuals buried at Sigatoka Sand Dunes site (Fiji) in Burial Ground 1 excavated by Simon Best in 1987 and 1988 using two approaches and a reassessment of their archaeological, bioarchaeological and chronological frame. First, stable carbon and nitrogen isotope analysis was applied to document dietary changes between childhood and adulthood using an intra-individual approach on paired bone-tooth. Second, the potential adaptation of the individuals to their environment was evaluated through regional and temporal comparisons using inter-individual bone analysis. Ten AMS radiocarbon dates were measured directly on human bone collagen samples, placing the series in a range of approximately 600 years covering the middle of the first millennium CE (1,888 to 1,272 cal BP). δ13C and δ15N ratios were measured on bone and tooth collagen samples from 38 adult individuals. The results show that δ15N values from tooth are higher than those s from bone while bone and tooth δ13C values are similar, except for females. Fifteen individuals were included in an intra-individual analysis based on paired bone and tooth samples, which revealed six dietary patterns distinguished by a differential dietary intake of marine resources and resources at different trophic levels. These highlight sex-specific differences not related to mortuary practices but to daily life activities, supporting the hypothesis of a sexual division of labour. Compared to other Southwest Pacific series, Sigatoka diets show a specific trend towards marine food consumption that supports the hypothesis of a relative food self-sufficiency requiring no interactions with other groups., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Herrscher et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

In the Jiyang Sub-basin, Carboniferous-Permian (C-P) coal-measure source rocks have experienced complex multistage tectonics and therefore have a complex history of hydrocarbon generation. Because these coal measures underwent multi-stage burial and exhumation, they are characterized by various burial depths. In this study, we used the basin modeling technique to analyze the relationship between burial history and hydrocarbon generation evolution. The burial, thermal and maturity histories of C-P coals were reconstructed, including primary hydrocarbon generation, stagnation, re-initiation, and peak secondary hydrocarbon generation. The secondary hydrocarbon generation stage within this reconstruction was characterized by discontinuous generation and geographical differences in maturity due to the coupled effects of depth and a delay of hydrocarbon generation. According to the maturity history and the delay effect on secondary hydrocarbon generation, we concluded that the threshold depth of secondary hydrocarbon generation in the Jiyang Sub-basin occurred at 2,100 m during the Yanshan epoch (from 205 Ma to 65 Ma) and at 3,200 m during the Himalayan period (from 65 Ma to present). Based on depth, residual thickness, maturity, and hydrocarbon-generating intensity, five favorable areas of secondary hydrocarbon generation in the Jiyang Sub-basin were identified, including the Chexi areas, Gubei-Luojia areas, Yangxin areas, the southern slope of the Huimin depression and southwest of the Dongying depression. The maximum VRo/burial depth (%/km) occurred in the Indosinian epoch as the maximum VRo/time (%/100Ma) happened in the Himalayan period, indicating that the coupling controls of temperature and subsidence rate on maturation evolution play a significant role in the hydrocarbon generation evolution. A higher temperature and subsidence rate can both enhance the hydrocarbon generation evolution. [ABSTRACT FROM AUTHOR]

degree of formation deformation. It is closely related to structural evolution, differential compaction and basement activities. In this paper, we have systematically analyzed the current structural characteristics, structural evolution and gascontrolling effects of the Upper Paleozoic in the northern Ordos Basin, based on a large amount of drilling, logging and seismic data and numerical simulation method. The results show that the upper Paleozoic in the study area is characterized by open folds of equal thickness (isopach fold). The formation mechanism of equal-thick open folds in this area is mainly horizontal bending folds, and it is mainly affected by the multi-period extensional tectonic stress environment since the Late Cretaceous (K.2). The tectonic activity in this period caused the differential extension and final shaping of the low-amplitude structure. The structural burial history of different areas in the study area has certain similarities. This shows that since the Late Cretaceous (K.2), this area has been uplifted and eroded as a whole, but the erosion intensity has gradually increased from west to east. The denudation characteristics of different areas are similar, indicating that the denudation is synchronized. "Palaeo-uplift" or "anticline structure with paleo-uplift shape" are mostly inherited. Most current low-amplitude structures are paleo-tectonic highs. The low-amplitude structural uplift area and its flanks have the largest degree of deformation and high degree of fracture development, and the productivity of gas wells in these areas is relatively high. Therefore, the high point of the current structure is a favorable place for the preferential accumulation of natural gas. [ABSTRACT FROM AUTHOR]

Stone tools stratified in alluvium and loess at Korolevo, western Ukraine, have been studied by several research groups 1-3 since the discovery of the site in the 1970s. Although Korolevo's importance to the European Palaeolithic is widely acknowledged, age constraints on the lowermost lithic artefacts have yet to be determined conclusively. Here, using two methods of burial dating with cosmogenic nuclides 4,5 , we report ages of 1.42 ± 0.10 million years and 1.42 ± 0.28 million years for the sedimentary unit that contains Mode-1-type lithic artefacts. Korolevo represents, to our knowledge, the earliest securely dated hominin presence in Europe, and bridges the spatial and temporal gap between the Caucasus (around 1.85-1.78 million years ago) 6 and southwestern Europe (around 1.2-1.1 million years ago) 7,8 . Our findings advance the hypothesis that Europe was colonized from the east, and our analysis of habitat suitability 9 suggests that early hominins exploited warm interglacial periods to disperse into higher latitudes and relatively continental sites-such as Korolevo-well before the Middle Pleistocene Transition., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Understanding how physical properties and seismic signatures of present day rocks are related to ancient geological processes is important for enhanced reservoir characterization. In this paper, we have studied this relationship for the Kobbe Formation sandstone in the Barents Sea. These rocks show anomalous low shear velocities and high VP/VS ratios, which does not agree well with conventional rock physics models for moderately to well consolidated sandstones. These sandstones have been buried relatively deeply and subsequently uplifted 1–2 km. We compared well log data of the Kobbe sandstone with velocity–depth trends modelled by integrating basin modelling principles and rock physics. We found that more accurate velocity predictions were obtained when first honouring mechanical and chemical compaction during burial, followed by generation of micro‐cracks during uplift. We suspect that these micro‐cracks are formed as overburden is eroded, leading to changes in the subsurface stress‐field. Moreover, the Kobbe Formation is typically heterogeneous and characterized by structural clays and mica that can reduce the rigidity of grain contacts. By accounting for depositional and burial history, our velocity predictions become more consistent with geophysical observables. Our approach yields more robust velocity predictions, which are important in prospect risking and net erosion estimates. [ABSTRACT FROM AUTHOR]

This study aims to evaluate source rock formations (Kareem and Rudeis) through quantitative and qualitative analysis of pyrolysis data from 44 ditch samples from three wells (Elkhaligue-1, Kareem-1, and El Ayune-1) at different depths in the central Gulf of Suez. From these data we concluded that Kareem and Rudeis formations are fair to good source rocks and have a generating potential fair to good to generate both oil and gas generated from mixed type II kerogene deposited under anoxic conditions, also they considered as fair to good oil sources. Both formations are mature and this conclusion is confirms by the burial histories of the three wells where Kareem Formation reached the early stage of generation at time ranges from 6 to 1.5 m.y while Rudeis Formation reached the oil window at time ranges from 18 to 6.6 m.y which considered a very good timing for excellent preservation efficiency of the hydrocarbons generated. [ABSTRACT FROM AUTHOR]

This study presents a 3D numerical model of a study area in the NW part of the Persian Gulf, offshore SW Iran. The purpose is to investigate the burial and thermal history of the region from the Cretaceous to the present day, and to investigate the location of hydrocarbon generating kitchens and the relative timing of hydrocarbon generation/migration versus trap formation. The study area covers about 20,000 km2 and incorporates part of the intra‐shelf Garau‐Gotnia Basin and the adjacent Surmeh‐Hith carbonate platform. A conceptual model was developed based on the interpretation of 2700 km of 2D seismic lines, and depth and thickness maps were created tied to data from 20 wells. The thermal model was calibrated using bottom‐hole temperature and vitrinite reflectance data from ten wells, taking into account the main phases of erosion/non‐deposition and the variable temporal and spatial heat flow histories. Estimates of eroded thicknesses and the determination of heat‐flow values were performed by burial and thermal history reconstruction at various well and pseudo‐well locations. Burial, temperature and maturation histories are presented for four of these locations. Detailed modelling results for Neocomian and Albian source rock successions are provided for six locations in the intra‐shelf basin and the adjacent carbonate platform. Changes in sediment supply and depocentre migration through time were analyzed based on isopach maps representing four stratigraphic intervals between the Tithonian and the Recent. Backstripping at various locations indicates variable tectonic subsidence and emergence at different time periods. The modelling results suggest that the convergence between the Eurasian and Arabian Plates which resulted in the Zagros orogeny has significantly influenced the burial and thermal evolution of the region. Burial depths are greatest in the study area in the Binak Trough and Northern Depression. These depocentres host the main kitchen areas for hydrocarbon generation, and the organic‐rich Neocomian and Albian source rock successions have been buried sufficiently deeply to be thermally mature. Early oil window maturities for these successions were reached between the Late Cretaceous (90 Ma) and the early Miocene (18 Ma) at different locations, and hydrocarbon generation may continue at the present‐day. [ABSTRACT FROM AUTHOR]

Abstract Shallow marine to peritidal carbonates of the Triassic Csukma Formation in the Mecsek Mts. of SW Hungary are made up of dolomites, limestones and dolomitic limestones that show evidence of a complex diagenetic history. Integration of petrographic, conventional stable oxygen and carbon isotope, clumped isotope, and strontium isotope data with the paleogeography, paleoclimate, and burial history of the region revealed four major diagenetic stages. Stage 1: The peritidal carbonates were dolomitized penecontemporaneously during the Middle Triassic by refluxing evaporatively concentrated brines. Stage 2: Increasing burial during the Late Triassic–Jurassic resulted in recrystallization of the Kán Dolomite Member in an intermediate burial setting. Stage 3: During the Early Cretaceous seawater was drawn down and circulated through rift-related faults, causing renewed recrystallization of the Kán Dolomite Member as well as dolomitization of the Kozár Limestone Member and the underlying limestones in a deep burial setting, but only in the vicinity of the faults. Stage 4: During the Late Cretaceous and Cenozoic thrusting resulted in tectonic expulsion of basinal fluids and precipitation of multiple saddle dolomite cement phases near the faults. The results of this study imply that the clumped isotope method integrated with other geochemical data can successfully be applied to identify the nature and potential sources of extra-formational diagenetic fluids responsible for dolomitization and recrystallization. This study provides conclusive evidence for multi-phase dolomitization and dolomite recrystallization over several millions of years (Middle Triassic through Early Cretaceous) and several thousands of meters of burial in the Csukma Formation in SW Hungary. Furthermore, this study is the first to identify fault-controlled dolomitization by circulating Cretaceous seawater within Triassic carbonates of central Europe, further supporting the viability of the interpretation of dolomitization by seawater initially drawn down and then geothermally circulated through faults in extensional basins. Highlights • Multi-phase dolomitization and dolomite recrystallization in SW Hungary. • Reflux dolomitization of Middle Triassic peritidal carbonates. • Intermediate burial recrystallization of reflux dolomites in connate waters. • Fault-controlled dolomitization/recrystallization by convecting Cretaceous seawater. • Synergistic application of carbon, oxygen, strontium and clumped isotope methods. [ABSTRACT FROM AUTHOR]

Abstract The Δ 47 clumped isotope thermometer has been applied to multiple studies aimed at reconstructing the paleoelevation and paleoclimate of sedimentary basins and paleosol sequences. Ideally, this technique directly preserves the temperature of carbonate formation, avoiding any speculation on the composition of surface water from which the carbonate precipitated. Recently, however, concerns about post-depositional alteration of the Δ 47 isotope signature from the effects of burial and/or diagenetic alteration have arisen, potentially complicating the application of the Δ 47 clumped isotope thermometer for determining paleo-surface temperatures. Here we investigate the effect of burial history on mass-47 clumped isotope. To this purpose we collected samples, from the surface and from drill cores, in two different areas of the Greater Green River basin: the Washakie Basin near Rock Springs, Wyoming and the Green River Basin near Pinedale, Wyoming. Both basins are filled with a thick sequence of Eocene lacustrine strata and the thermal histories of both basins are well documented from petroleum prospecting studies. Clumped isotope Δ 47 compositions were measured from lacustrine micritic limestones with a range of peak burial depths from 1 to 6.5 km. For samples from the Washakie Basin that did not experience burial depths exceeding ∼2000 meters, the measured Δ 47 values vary from 0.623‰ to 0.684‰, yielding carbonate formation temperatures consistent with previously hypothesized Paleocene-Eocene surface temperatures. In contrast, samples from the Green River Basin, collected from greater burial depths, demonstrate significantly lower Δ 47 values (higher temperatures). The consistency of δ18O values and lack of CL evidence for recrystallization suggest closed-system resetting of the clumped isotope thermometer by either partial solid-state re-ordering or carbonate reprecipitation during burial. The Δ 47 values of the deeply buried samples have been compared to values derived from recrystallization and temperature history reordering models (THRMs). Both recrystallization and reordering models are successful at predicting Δ 47 reordering at burial temperatures >100 °C. These observations, from samples collected from a basin with a remarkably well-constrained thermal history and geothermal gradient, highlight the challenges in elucidating burial histories or diagenetic processes solely from clumped isotopic compositions. [ABSTRACT FROM AUTHOR]