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Three new fossil species of walnuts, Juglans eoarctica sp. nov., J. nathorstii sp. nov., and J. cordata sp. nov., are described on the basis of nuts recovered from the middle Eocene fossil forests of Axel Heiberg Island in the Canadian Arctic Archipelago. These represent the most northerly occurrence of Juglans and are among the oldest records of Juglans to date. The Axel Heiberg Island walnuts conform to the sections Rhysocaryon and Cardiocaryon and, together with the contemporaneous midlatitude fossil species J. clarnensis Scott, imply the establishment of two distinct Juglans lineages prior to the middle Eocene. Climatic cooling, leading ultimately to Pleistocene glaciation, has transformed high-latitude vegetation and resulted in the American/Eurasian disjunct distribution found in many north temperate families, of which Juglans is typical. With three coexisting species in the Axel Heiberg Island fossil forests, it is clear that Juglans was an important component of this ancient polar landscape and played a significant role in the evolution of northern temperate forest ecosystems. [ABSTRACT FROM AUTHOR]

Based on a single specimen in Eocene Baltic amber, Henoticus groehni sp. nov., the first extinct species of the genus, is described. The new species is studied and illustrated in detail using optical microphotography and X-ray micro-computed tomography. An additional congeneric specimen is discussed but not attributed to the species level. It is shown that exoskeletal depressions on the metaventrite with possible mycangia roles were present in Henoticus already in the Eocene. The possible involvement of the newly described species in dynamic of ecosystems at the early stages of natural pyrogenic succession in Eocene amber forests is hypothesised. [ABSTRACT FROM AUTHOR]

Aim: Modern sharks are a diverse and highly threatened group playing important roles in ecosystems. They have an abundant fossil record spanning at least 250 million years (Myr), consisting primarily of isolated teeth. Throughout their evolutionary history, sharks have faced multiple environmental changes and extinction events. Here, we aim to use dental characters to quantify how shark functional diversity has changed during the last 66 Myr. Location: Global. Time period: Cenozoic era (66–0 million years ago; Ma). Major taxa studied: Sharks (Selachii). Methods: We complied a dataset of over 9000 shark teeth belonging to 537 taxa from museum collections and scientific literature and measured six dental characters strongly linked with functional traits. We then quantified different functional diversity metrics across Cenozoic time bins, compared them against null expectations and identified the most important taxa contributing to maintaining functional diversity. Results: Sharks displayed relatively high functional diversity during the Cenozoic, with 66%–87% of the functional space being occupied for ~60 Myr (Palaeocene to Miocene). High levels of functional redundancy during this time resulted in larger‐than‐expected functional richness; but a large decline (−45%) in redundancy in the Oligocene (~30 Ma) left shark functional diversity highly vulnerable to further loss. Shark functional diversity declined from the late Miocene (~10 Ma) onwards, losing 44% of functional richness by the Recent. Extinct sharks disproportionally contributed to the Cenozoic functional diversity and spanned a wider range of functional space than extant sharks, with the loss of mid‐sized suction feeders and large‐bodied predators driving functional declines. Main conclusions: After maintaining high levels of functional diversity for most of the Cenozoic, sharks lost nearly half of their functional diversity in the last ~10 Myr. Current anthropogenic pressures are therefore likely eroding an already diminished shark functional diversity, leaving future communities ecologically deprived compared with their thriving geological past. [ABSTRACT FROM AUTHOR]

The southern Central Andes (∼25–40°S) exhibit a complex tectonic history, crucial for understanding orogenic processes in subduction-related orogens, yet debate on the timing and mechanisms of early Cenozoic topographic growth persists. We present double-dated detrital zircon U-Pb and (U-Th)/He thermochronology data from the early Oligocene–Miocene Bermejo Basin at ∼30°S to investigate source unroofing during development of the High Andes. (U-Th)/He results yield dates of ca. 565–16 Ma (n = 73), with distinct detrital modes that indicate a mixing of sediment sources characterized by variable cooling and exhumation histories. We employ a novel approach for modeling detrital thermochronology data that leverages the shared basin subsidence history of multiple detrital modes to resolve provenance and source unroofing histories. Results from the lower Oligocene Vallecito Formation (northwestern Argentina) reveal that detritus was sourced from Permian–Triassic Choiyoi Group rocks that underwent rapid late Eocene cooling, indicated by short lag time (2–5 m.y.) between source cooling and deposition. Our findings are consistent with bedrock studies of Eocene exhumation in the High Andes and establish source-to-basin connectivity during this time. Other detrital modes with pre-Cenozoic cooling histories were derived from Carboniferous Elqui-Colangüil and Choiyoi Group rocks or recycled from Paleozoic basins. We propose that an early Oligocene drainage divide in the High Andes was located west of the Punilla–La Plata fault, an active thrust front at ∼30°S. These findings challenge Paleogene neutral stress-state models for the Andes and underscore the importance of improved knowledge of erosion and deformation histories for refining models of Andean orogenesis. [ABSTRACT FROM AUTHOR]

Delamination of lower continental lithosphere is known to have occurred under different tectonic settings. However, its fate in the mantle is poorly understood. By analyzing global seismic models, we find that most of likely lithosphere that delaminated during the Cenozoic and Mesozoic is preserved in the mantle transition zone, especially beneath North America and Africa. Numerical experiments indicates that delaminated lithosphere can remain stagnant in the mantle transition zone for tens of millions of years, followed by its potential sinking into the lower mantle or re‐rising to shallower depths depending on its density, the Clapeyron slope of the spinel‐to‐post‐spinel phase change and increase in mantle viscosity at ∼660–1,000 km depths. Re‐ascent occurs when delaminated lithosphere is reheated so that its effective density becomes lower than its surrounding ambient mantle after ∼100 Myr. Delaminated fragments can also potentially be mobilized by underlying global mantle flow to move horizontally away from plume regions. Plain Language Summary: The phenomenon of lower lithospheric delamination has been recognized in various tectonic settings, but the ultimate fate of these delaminated fragments within the mantle remains poorly known. From global seismic tomographic models, we gain first‐order constraints on the potential locations of geologically recent (<250 Ma) delaminated lithosphere, particularly in regions distant from subduction zones. A significant portion of Cenozoic and Mesozoic delaminated lithosphere appears to still be sequestered within the mantle transition zone, with pronounced concentrations beneath the Mesozoic and Cenozoic locations of North America and Africa. Numerical simulations further corroborate the hypothesis that these fragments of delaminated lithosphere can remain stagnant within the mantle transition zone over these geologically interesting timescales. Delaminated lithosphere can also re‐rise or move horizontally depending on underlying global mantle flow. Key Points: Seismic tomographic models provide first‐order constraints on the location of recent delaminated lithosphere in the upper and mid‐mantleDelaminated lithosphere can remain stagnant in the mantle transition zone for tens to hundreds of millions of yearsDepending on underlying mantle flow, delaminated lithosphere can also eventually warm and rise, or even move horizontally [ABSTRACT FROM AUTHOR]

Shifts in environmental conditions can impose strong selection for adaptive traits. During the Cenozoic era, as the oceans cooled, many marine teleost fish species were at risk of freezing. This led to the independent emergence of distinct ice‐binding antifreeze proteins (AFPs). The report in this issue by Graham and Davies reveals the development of AFP genes in shorthorn and longhorn sculpin from a copy of the lunapark gene. The predicted sculpin AFP sequences are unrelated to that of lunapark; the coding sequences for the AFPs appear to have arisen from small portions of the lunapark gene by codon frameshifting along with a series of mutations. [ABSTRACT FROM AUTHOR]

The effective utilization of medium-high temperature geothermal energy is pivotal in reducing carbon emissions and plays a crucial role in developing clean energy technologies. The MiDu geothermal field, situated in the southeastern region of Dali Prefecture, Yunnan Province, lies within the Mediterranean–Himalayan high-temperature geothermal belt and is characterized by abundant geothermal resources. However, due to its considerable depth, exploration poses significant risks, resulting in a total utilization rate of less than 0.5% of the total reserves. This study employs natural seismic data to perform a tomographic analysis of the geothermal system in the Midu basin. By examining the P-wave velocity (Vp) and the velocity ratio of P-waves and S-waves (Vp/Vs) at various depths, the findings reveal that the basin comprises two distinct structural layers: the thrust basement of the Mesozoic and Paleozoic eras and the strike–slip extensional sedimentary layer of the Cenozoic era. A low-velocity anomaly in the central basin corresponds to the loose Cenozoic sedimentary layer. In contrast, high-velocity anomalies at the basin edges correlate with boundary faults and the Mesozoic–Paleozoic strata. Below a depth of 4 km, the Red River Fault and MiDu Fault continue to dominate the basin's structure, whereas the influence of the Malipo Fault diminishes. The MiDu Fault exhibits higher thermal conductivity than the Yinjie Fault. It interfaces with multiple carbonate and basalt formations characterized by well-developed pores and fractures, making it a crucial conduit for water and a control point for geothermal storage. Consequently, the existence of medium-high temperature (>90 °C) geothermal resources for power generation should be concentrated around the Midu fault on the western side of the basin, while the Yinjie fault area is more favorable for advancements in heating and wellness. [ABSTRACT FROM AUTHOR]

The Abaga basalts, which erupted within an intraplate background in the late Cenozoic, are situated in eastern central Inner Mongolia. Previous studies have explored the genesis of these basalts, which were influenced by the subduction of slab. Although trace element ratios demonstrate that altered oceanic crust (AOC) and sediments have contributed to the genesis of the basalts, limited information about the detailed percentages of mixing among sediments, AOC, and depleted mantle (DM) based on Sr‒Nd‒Pb isotopic values has been reported. In this study, we modelled the possible mixing percentages among AOC, DM, and sediments. The calculated results illustrate that a proportion of 80% DM, 16% AOC, and 4% sediments is appropriate for interpreting the Sr‒Nd‒Pb isotopic variation of the basalts. In addition, the associated major and trace elements of olivine and the partition coefficient of V between olivine and melt are used to estimate the crystallization temperatures of the olivine phenocrysts and oxygen fugacity of the basalts. The calculated results display that the olivine mainly crystallized between 1248 and 1293°C (standard error estimate: 51°C), and the fO2 values of the Abaga basalts range from FMQ + 0.14 to FMQ + 1.46 (FMQ, fayalite–magnetite–quartz buffer). The estimated oxygen fugacity values plot in the range of island arc basalts (from FMQ to FMQ + 2) but are higher than those of both mid-ocean ridge basalt (MORB) (from FMQ-0.4 to FMQ + 0.5) and Abaga xenoliths (from FMQ-1.55 to FMQ + 0.53), which indicates that the basaltic melts were more oxidized than those of MORB and the Abaga lithospheric mantle. Furthermore, the primary magma and the corresponding mantle source were more oxidized than MORB. The Ba/Th and Ce/Pb ratios of the basalt present positive correlations with fO2 values, demonstrating that the addition of sediments and oceanic crust into the mantle source may have contributed to increasing the fO2 values of the basalts. [ABSTRACT FROM AUTHOR]

This study presents a novel approach to map the structural configuration of the northern part of the Central Indian Ridge from satellite-derived gravity data. The proposed approach is based on a combination of derivatives of the horizontal gradient of gravity anomalies. The robustness of the approach is tested on synthetic gravity examples before applying it to satellite gravity data of the northern part of the Central Indian Ridge. The results obtained from the synthetic examples show that the proposed method can map the structural boundaries more precisely and clearly compared to other techniques, and can avoid producing additional structures in output maps. For real application, the structural features determined from the proposed approach are consistent with the fracture zones that have been identified in the area. The obtained result reveals the prominent lineament trend is in the northeast-southwest direction, which is possibly related to plate movement during the Cenozoic. The result demonstrates a high lineament density that is in agreement with the slow spreading rate of the Central Indian Ridge. My findings also demonstrate that the proposed approach can be considered as a valuable tool in mapping structural boundaries. [ABSTRACT FROM AUTHOR]

Van Valen's law of constant extinction postulates that in comparable ecological contexts, the probability for a taxon to survive to the next time interval is independent of how long it has already existed. The law implies that species do not age, that is, the survival probability from one time step to the next does not decrease with species' age. While the original law describes survivorship over time, here we show that there is a counterpart to the law describing species dynamics in space. Indeed, the probability for a taxon to expand a step further in its range size does not depend on how large of a range the taxon already occupies. We show that such patterns of stochastically constant expansion are common in the global mammalian fossil record throughout the Cenozoic and are consistent with the mammalian species distribution in the present-day world. Intriguing is that the law in space holds best for the linear dimension of the range rather than for the range area. We interpret this as suggesting that species primarily expand via the frontier of their range; this process is known as leading-edge expansion in ecology. And while the difficulty of expanding in linear steps remains constant, the area gains diminish. In line with evolutionary theory collectively known as the Red Queen's hypothesis, this suggests that the effectiveness of expansion saturates, even if species longevity does not. When interpreted in reverse, this explains from the macroevolutionary perspective why larger species ranges are associated with lower extinction risks. [ABSTRACT FROM AUTHOR]

The West Kunlun orogenic belt located in the northwestern margin of the Qinghai-Tibet Plateau is an important record of the formation and northward extension of the plateau, but the current research mainly focuses on the tectonic activities of the Cenozoic era, and there is still considerable controversy regarding the formation and evolutionary history of pre-Cenozoic orogenic belts. This study focuses on Cretaceous sandstone samples from the Kedong region in the piedmont belt of the West Kunlun orogenic belt. U-Pb geochronological analysis was performed on 200 detrital zircon grains from the core samples. Combined with stratigraphic data and previous research, the main provenance direction was investigated to constrain the tectonic evolutionary history of the orogenic belt's peripheral regions. The results show that the detrital zircons are aged from 290 to 208 Ma, 520-310 Ma, 810-580 Ma, 1,400-880 Ma and 2,548-1,730 Ma, reflecting the complexity of provenance in this area. Based on a comprehensive analysis of the characteristics of igneous rocks, zircon age composition and stratigraphic conditions in potential source areas, it is concluded that the primary source regions include the East Kunlun orogenic belt and the North and South Kunlun terranes, with a low likelihood of contributions from within the Tarim Basin. The evolution of the West Kunlun orogenic belt can generally be divided into two opening and two closing phases. The detrital zircon ages predominantly exhibit two peak values at 259 Ma and 459 Ma, respectively representing the ages of transition from oceanic crust subduction to continentcontinent collision for the Paleo-Tethys Ocean and the Proto-Tethys Ocean. Additionally, there is a temporal gap between the evolution of the Proto-Tethys Ocean and the Paleo-Tethys Ocean. The Triassic period marks a transitional phase in tectonic evolution, shifting into an intracontinental evolutionary stage. This study provides new geochronological evidence for the early developmental history of the West Kunlun orogenic belt. [ABSTRACT FROM AUTHOR]

We describe a new species of Ampelopsideae (Vitaceae), Nekemias mucronata sp. nov., from the Rupelian of Cervera (Spain) and revise another fossil species, Ampelopsis hibschii, originally described from Germany. Comparison with extant Ampelopsideae suggests that the North American species Nekemias arborea is most similar to Nekemias mucronata while the East Mediterranean Ampelopsis orientalis is the closest living relative of A. hibschii. Our review of fossil data indicates that, during the Eocene, four species of Ampelopsideae occurred in Eurasia, that is, N. mucronata in the Czech Republic, A. hibschii in Kazakhstan, and two fossil species in the Far East (Ampelopsis cercidifolia and Ampelopsis protoheterophylla). In the Oligocene, a new species, Ampelopsis schischkinii, appeared in Kazakhstan; meanwhile, N. mucronata spread eastwards and southwards, and A. hibschii mainly grew in Central Europe. In the late Oligocene, N. mucronata became a relict in the Iberian Peninsula and Nekemias might have persisted in Western Eurasia until the latest Miocene (“Ampelopsis” abkhasica). The last occurrence of A. hibschii was in the Middle Miocene in Bulgaria, probably a refuge of humid temperate taxa, along with Ampelopsis aff. cordata. Carpological remains suggest that this lineage persisted in Europe at least until the Pleistocene. Our data confirm previous notions of the North Atlantic and Bering land bridges being important dispersal routes for Ampelopsideae. However, such dispersion probably occurred during the Paleogene rather than the Neogene, as previously suggested. A single species of Ampelopsideae, A. orientalis, has survived in Western Eurasia, which appears to have been linked to a biome shift. [ABSTRACT FROM AUTHOR]

The Rakaia River in the South Island of New Zealand is a unique catchment in which to trace active detrital gold transport, deformation and concentration from near-coeval orogenic sources. The catchment hosts widespread small late Cenozoic hydrothermal alteration zones, some of which are gold-bearing, in actively rising and eroding mountain headwaters. Detrital gold liberated from the sources is distinctively porous with abundant micron-scale silicate inclusions, especially albite. Fine gold (∼200–100 µm) has been transported >100 km downstream, but coarse gold remains highly diluted in proximal fluvial sediments. Fine gold is also diluted by coarse fluvial sediments that form the upper kilometre of the Canterbury sedimentary basin southeast of the mountain front. Minor re-concentration of fine gold occurs in a bedrock gorge at the mountain front, and on steep ocean beaches beyond the river mouth. Despite the long-distance transport, the fine gold particles have been only superficially modified by surface smearing and minor flattening. The gold may have travelled in suspension in the river, buoyed by electrostatically adhering fine micas, in contrast to detrital garnets that were rounded in bed-load. In contrast, detrital gold on the western side of the mountains has been flattened to thin flakes during bed-load transport. [ABSTRACT FROM AUTHOR]

The nitrogen isotopes of the organic matter preserved in fossil fish otoliths (ear stones) are a promising tool for reconstructing past environmental changes. We analyzed the 15N/14N ratio (d15N) of fossil otolith-bound organic matter in Late Cretaceous fish otoliths (of Eutawichthys maastrichtiensis, Eutawichthys zideki and Pterothrissus sp.) from three deposits along the US east coast, with two of Campanian (83.6 to 77.9 Ma) and one Maastrichtian (72.1 to 66 Ma) age. d15N and N content were insensitive to cleaning protocol and the preservation state of otolith morphological features, and N content differences among taxa were consistent across deposits, pointing to a fossil-native origin for the organic matter. All three species showed an increase in otolith-bound organic matter d15N of ~4‰ from Campanian to Maastrichtian. As to its cause, the similar change in distinct genera argues against changing trophic level, and modern field data argue against the different locations of the sedimentary deposits. Rather, the lower d15N in the Campanian is best interpreted as an environmental signal at the regional scale or greater, and it may be a consequence of the warmer global climate. A similar decrease has been observed in foraminifera-bound d15N during warm periods of the Cenozoic, reflecting decreased water column denitrification and thus contraction of the ocean's oxygen deficient zones (ODZs) under warm conditions. The same d15N-climate correlation in Cretaceous otoliths raises the prospect of an ODZ-to-climate relationship that has been consistent over the last ~80 My, applying before and after the end-Cretaceous mass extinction and spanning changes in continental configuration. [ABSTRACT FROM AUTHOR]

A new species Arachnocoris furtivinabis Ma, Du et Yao sp. nov. is described and illustrated, which represents the first fossil record of Arachnocoris, also the first record in the family Nabidae from Cenozoic Dominican amber. Based on the distinctive morphological characters in this new species, including antennomere II much shorter than twice of antennomere I, labial segment III slightly longer than segment II, and parameres round, it is differentiated from other species within Arachnocoris. Compared with the spider-webdwelling taxa of the extant and extinct species in Heteroptera, the evolution of predation strategies for this special group during the Miocene was discussed. [ABSTRACT FROM AUTHOR]

Coal gasification to manufacture dihydrogen (H 2) has long been known as a surface process. Recent works have also highlighted the H 2 generating potential of the Organic Matter (OM). The evolution of OM generates H 2 all along the process but this gas is only expected to remain as free H 2 after the maturation and expulsion of the hydrocarbons (HC) which means at a high temperature of above 200 °C. In this paper we studied the potential of three different tertiary coals from Amaga, La Jagua de Ibirico and Barrancas, all located in Colombia. Their H 2 yields were studied using a pyrolyser and the kinetic of the H 2 generation were quantified. All the studied coals are immature to early mature as source rock (SR) with large TOC content, between 66 and 83%, and good H 2 potential. The highest values were found for the Barrancas area where the potential reached 25 mg H 2 /g TOC. The temperature corresponding to the peak of H 2 generation is between 740 and 800 °C depending of the heating rate. This corresponds to the 200–300 °C for the H 2 kitchen, even if the H 2 generation starts before as already observed for continental organic rich source rock. Comparison with the other coals shows that H 2 potential is linear with TOC. In the Colombian coals, the H 2 yield in mg H 2 /g of rock is around 1/4 of the TOC content. In average, these coals have so a H 2 yield about 10 000 mmol H 2 /kg of rock, two orders of magnitude above the "best" olivines. It should nevertheless be kept in mind that the extrapolation of these laboratory data to sedimentary basins remains unconstrained and will need to be refined when well data and modelling tools are available. • The coals have significant H 2 potential in deep sedimentary basins. • High temperature open-system pyrolizer can be used to quantify these H 2 yield. • The reaction kinetic of the H 2 generation from coal is of order 1 and H 2 window generation can extend from 200 to 400 °C. • The Cenozoic Colombian coal's yield of H 2 in mgH 2 /g rock is ca ¼ of its organic carbon content in percentage. • A 80% TOC rich coal has a H 2 yield two orders of magnitude higher than that of olivines at a similar temperature of 250 °C. [ABSTRACT FROM AUTHOR]

There are five tectonomagmatic stages in the evolution of Magellan Seamount guyots: 1, Late Jurassic–Early Cretaceous (Earliest Cretaceous, ∼160–140 (?) Ma); 2, Early Cretaceous (Late Barremian (?)–Aptian–Albian, ∼127–96 Ma); 3, Late Cretaceous (Late Cenomanian (?)–Turonian–Early Campanian, ∼95–76 Ma); 4, Late Cretaceous (Late Campanian–Maastrichian, ∼74.5–66.0 Ma); 5, Cenozoic, 66–0 Ma. Each of the tectonomagmatic stages corresponds to a specific age complex of volcanic rocks of the Magellan Seamounts. Tectonomagmatic stages have different durations and played different roles in the evolution and formation of the modern structure of Magellan Seamount guyots. Each of the tectonomagmatic stages characterizes a specific geomorphological space of guyots (base, main part of the structure, small complicating overprinted second-order structures). In general, the tectonomagmatic stages in the evolution of the Magellan Seamounts agree well with the stages of the evolution of some other regions of the Pacific Ocean and correspond to the earlier established periods of their tectonomagmatic activation. [ABSTRACT FROM AUTHOR]

The results of studies of the regional structure of Solenovian deposits of the Early Oligocene Rupelian Stage in the Cisсaucasian–Caspian region, which represented the northern slope of Eastern Paratethys in the Cenozoic, are presented. The geological structure and paleogeographic conditions in the basin during the Solenovian (second half of Early Oligocene) were refined based on a comprehensive interpretation of geological and geophysical materials. The spatial consequences of the sea level drop in Eastern Paratethys during the Oligocene regressions are traced. The periodic draining of shelf areas is reflected in the structure of erosional unconformities and buried river incisions. It has been established that the most significant was the late Solenovian regression with a relative sea level drop by more than 500 m. Consequently, a prominent unconformity surface, complicated by river incisions, was formed in the sedimentary sequence in the shelf part of the paleobasin (Maikop seismic sequence). Erosion ledges and landslide bodies formed on the slopes, and basin-infill complexes were accumulated in depressions. [ABSTRACT FROM AUTHOR]

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The Gudong area contains abundant petroleum resources. Previous studies have mainly focused on the extension structure in this area, with its strike-slip characteristics remaining poorly understood. In this study, the geometry of the strike-slip faults in the Gudong area was investigated using high-resolution 3D seismic reflection and drilling data, as were their associated releasing and restraining structures. Based on the profile's flower structure and the plane's horsetail splay pattern, the Gudong fault in the study area can be characterized as a dextral strike-slip. Three types of strike-slip fault-associated structures can be identified in the study area: (a) a restraining bend occurring in the right-stepping area of the S-shaped Gudong strike-slip fault, (b) a restraining bend identified in the left-stepping, overlapping zone of the Gudong and Kendong faults, and (c) a releasing bend seen in the extensional horsetail splay structure at the southern end of the Gudong fault. The restraining stress induced the formation of a fault-related open anticline, which led to a significant increase in fault sealing efficiency, thereby preserving an estimated 75.479231 million tons of oil and 15.28317145 billion cubic meters of gas. Conversely, releasing transtensional stress has compromised the effectiveness of the traps, preventing hydrocarbon retention. Consequently, oil and gas have migrated upward along the horsetail faults to the top of Cenozoic formations and have then dispersed. [ABSTRACT FROM AUTHOR]

We investigate the crustal structure of the Northeastern (NE) South China Sea (SCS) rifted margin to constrain its crustal thickness and basement nature with implications for the Mesozoic and Cenozoic evolution of the SCS. First‐order interfaces interpreted from seismic reflection data were integrated into a 3D gravity inversion scheme to determine Moho depth and crustal thickness variations. A joint inversion of seismic and gravity data allowed us to determine crustal density variations along 2D profiles. The distal margin of the NE SCS is divided into two distinct crustal domains: the Southern Rift System (SRS), and the Southern High (SH). The SRS shows an extremely thinned crust on top of which thick Cenozoic sequences are observed. It is separated from the oceanic crust (∼6–8 km thick) by the SH, a comparatively thicker crustal domain (∼10–15 km thick) with significant magmatic additions. The distal NE SCS margin formed during the Cenozoic rifting of the SCS. The SH likely corresponds to a polygenic piece of crust, recording polyphase magmatic activity since the Mesozoic, with potentially significant activity during Cenozoic post‐rift time. The NE SCS margin is conjugate to Palawan whose basement is considered to be part of the exotic Luconia microcontinent that collided with Eurasia during the Late Cretaceous. Basement similarities between Palawan and the SH are highlighted, suggesting that the latter might also be part of Luconia. Our results suggest that the docking/suture zone between Eurasia and Luconia might have acted as a preferred zone for the Cenozoic rift development. Key Points: The Northeastern South China Sea rifted margin shows a contrasted crustal structure constrained by seismic and gravity dataPart of the distal margin corresponds to a dense polygenic continental crust that underwent polyphase magmatic activityThe former Mesozoic suture zone between Eurasia and Luconia acted as a weakness zone for the Cenozoic rifting [ABSTRACT FROM AUTHOR]

The collisional Iranian Plateau and its recent kinematic evolution represent a natural example to study the intraplate response to the transferred deformation from an active convergent plate margin. The late Cenozoic deformation and structural evolution of the Plateau is not well understood. Here, we integrate structural, tectonostratigraphic, and morphotectonic field observations with low‐temperature thermochronometric data along the NW‐SE trending Kushk‐e‐Nosrat (KN) Fault to unravel the exhumation history and the kinematic change at the northwestern boundary of the Iranian Plateau. We found different sets of strike‐slip related structures along the KN Fault zone, which are classified into four categories based on their cross‐cutting relations and the superimposition of kinematic indicators. These include dextral transtension, dextral, dextral transpression, and sinistral kinematics. The unreset zircon (U‐Th)/He and apatite fission track results and the reset apatite (U‐Th)/He data from the restraining area along the KN Fault suggest 80–60°C of cooling during the early Miocene (∼20–18 Ma) and late Miocene–early Pliocene (∼7–5 Ma) due to dextral and dextral transpressional kinematics along the KN Fault zone, respectively. The dextral transtentional faulting was recorded as deposition of the Qom Formation within the releasing overlap areas along the KN Fault at >20–18 Ma. The kinematics of the KN Fault changed to sinistral during Pliocene–Quaternary times presumably triggered by the simultaneous clockwise rotation of central Iran, Alborz Mountains, and the South Caspian block. Our study proposes that the morphological and tectonostratigraphic evolution of the northern margin of the Iranian Plateau has mainly been controlled through local uplift and exhumation in restraining areas and local thick deposition in releasing areas of the major strike‐slip faults during the late Cenozoic time. Plain Language Summary: The collision between Arabia and Eurasia caused not only deformation at the collision front but also hundreds of kilometers far away in the plate's interior. This collisional process led to the formation of the highly elevated Iranian Plateau. In this study, we investigate the deformation history along the northern margin of the plateau, which is characterized by large strike‐slip faults. We present new data collected in the field along the >150 km long Kushk‐e‐Nosrat Fault Zone to reveal the various changes in strike‐slip deformation. Combined with new thermochronology data, we reveal four stages of faulting: dextral transtension, dextral, dextral transpression, and sinistral motion from the late Eocene to recent times. We can link these changes in deformation with the large‐scale tectonics of the Arabia‐Eurasia collision that underwent changes in the direction of plate motions and plate rotations relative to each other. Key Points: The Northern Iranian Plateau margin experienced dextral transtension, dextral, dextral transpression, and sinistral kinematics during the late CenozoicDextral and dextral transpression kinematics occurred at ∼20–18 Ma and ∼7–5 Ma, respectivelyUplift and exhumation in the NW Iranian Plateau margin focused on restraining areas along major faults during the late Cenozoic time [ABSTRACT FROM AUTHOR]

Cenozoic uplift in the Tianshan played an important role in driving Proto‐Paratethys Sea retreat and Asian aridification. However, most paleoclimate studies have focused on the Pamir‐Tianshan corridor, and frequently overlook the role of the entire Tianshan range in modifying the Central Asian climate during Cenozoic uplift. When and how Cenozoic deformation of Tianshan was initiated and propagated are intensively debated which makes its role in contributing to climate change in Central Asia more ambiguous. To address this issue, this study presents new detrital zircon U‐Pb and detrital apatite U‐Pb and fission track age data from Cenozoic sedimentary successions (54–0 Ma) in the northern margin of the Tarim Basin and integrates these data with published provenance data from adjacent regions. Our results show that deformation/uplift of the Baicheng‐Kuqa Depression and the South Tianshan occurred at ∼41–37 Ma and ∼24 Ma, when topographic growth of South Tianshan began to block the flow of sediment from the north. Continued uplift of the South Tianshan completely blocked fluvial transport from the Central Tianshan‐Yili Block by ∼10 Ma, as shown by the paucity of 380–310 Ma detrital zircons/apatites. Far‐field, north‐directed compressive stress resulting from the India‐Asia collision began to propagate toward the South Tianshan and its foreland during the Late Eocene, and continued to propagate into the South Tianshan and northward at the ∼24 Ma and 10 Ma. Finally, we suggest a two‐stage of aridification in the Tarim Basin which can be linked to two stages (∼24 and 10 Ma) of growth of the Tianshan. Plain Language Summary: The Tarim Basin and the Taklimakan Desert are located in Central Asia, between the Tibetan Plateau to the south and the Tianshan orogenic belt to the north. This region is a crucial area for exploring the primary drivers of Cenozoic desertification. We performed a systematic zircon and apatite provenance study (including detrital apatite and zircon U‐Pb dating, and detrital apatite fission track analysis) in Cenozoic strata from the northern margin of the Tarim Basin. Our results reveal pulsed deformation of the South Tianshan that initiated at ∼41–37 Ma with two subsequent pulses at ∼24 Ma and ∼10 Ma, the timing of which suggests a close link to the two‐step aridification (∼24 and 10 Ma) of the Tarim Basin. We suggest that the pulsed Cenozoic rise and growth of the South Tianshan played a crucial role in blocking westerly winds, restricting moisture from reaching the Tarim Basin, and driving Cenozoic aridification of the Tarim Basin. Key Points: Initiation of the Cenozoic uplift of the South Tianshan occurred in the Late EoceneFurther uplift of the South Tianshan completely blocked fluvial transport from the north by ∼10 MaPulsed growth of Tianshan play a dominant role in the two‐step aridification of the Tarim Basin [ABSTRACT FROM AUTHOR]

The Lhasa‐Qiangtang collision closed the Meso‐Tethys Ocean, but the exact timing of this event remains hotly debated. Here, we present geochronological and paleomagnetic analyses conducted on Cretaceous volcanics from western Qiangtang to constrain the Lhasa‐Qiangtang collision in western Tibet. Our investigations yield a paleolatitude of ∼30.5 ± 5.0°N for western Qiangtang during ca. 110–100 Ma. A reanalysis of previously acquired Mesozoic‐Cenozoic paleomagnetic data from western Qiangtang suggests a stationary position during ca. 136–34 Ma. Examination of paleomagnetic data from western Lhasa reveals a significant reduction in northward paleolatitudinal motion during the Early Cretaceous, dropping from ∼12.3 cm/yr to nearly zero. Integration of our paleomagnetic findings with available geological records has led to conclude that the Lhasa‐Qiangtang collision in western Tibet occurred at ca. 132 Ma. Additionally, we infer that crustal shortening on the order of ∼1,000 km happened between Lhasa and Qiangtang during the Early Cenozoic. Plain Language Summary: The Tibetan Plateau comprises multiple different blocks, which originated from the Gondwana in the southern hemisphere. Their convergence histories toward Euraisa have changed the global land‐sea distributions since the Late Paleozoic. The time at which the Lhasa block, one of the Tibetan blocks, accreted to the Qiangtang block to the north remains poorly constrained. In this work, we provide robust data suggesting a latitude of ∼30.5 ± 5.0°N for western Qiangtang during the Early Cretaceous (ca. 110–100 Ma). We also compiled the available latitudinal data from western Tibet in combination with geological observations. We suggest Lhasa collided with Qiangtang during 132 million years ago in western Tibet. Significant shortening of the continental crust by ∼1,000 km between the Lhasa and Qiangtang blocks occurred after their collision. Key Points: Western Qiangtang had a paleolatitude of ∼30.5 ± 5.0°N at ca. 110–100 MaA substantial decrease in the paleolatitudinal motion of western Lhasa occurred in the Early CretaceousThe Lhasa‐Qiangtang collision in western Tibet occurred at ca. 132 Ma [ABSTRACT FROM AUTHOR]

U–Pb, and zircon and apatite fission track data provide a powerful means to characterise the Late Cretaceous to Late Oligocene source-to-sink system and continent evolution in central Zealandia. Our dataset includes samples from potential source rocks in northwest Nelson (Takaka and Buller terranes; Karamea, Tobin, Darran and Separation Point suites) and Cenozoic sediments in the Taranaki and King Country basins. Zircon (ZFT) and apatite (AFT) fission track data for basement rocks indicate 7.5 to 10 km of Late Cretaceous to Paleogene exhumation, requiring a substantial Early Cretaceous to Paleogene mountain range in northwest Nelson, which was eroded to sea level by the Late Oligocene. Some 54% of the detrital zircon content in basin sandstone beds have Separation Point Suite U–Pb age, 24% have Karamea Batholith age and 19% have Darran and Tobin suites age. The remainder could be from the Buller and/or Takaka terranes. Revised Late Eocene and Oligocene paleogeographic maps for the basins define the sediment transport routes until termination during 29 to 26 Ma due to shortening across central to southern parts of the Taranaki Fault System, which dates the timing of subduction initiation along the Hikurangi margin of the modern Australia-Pacific plate boundary. [ABSTRACT FROM AUTHOR]

Despite the crucial role of the Southern Hemisphere (SH) westerlies in modulating modern and past climate evolution, little is known about their behavior and possible forcing mechanisms during the early Cenozoic. We probe changes in the hydroclimate of southwest Australia during 62–51 Ma, based on sedimentary proxy records from the International Ocean Discovery Program Site U1514 in the Mentelle Basin. Our results reveal a transition from a less humid climate to wetter conditions at mid–high latitudes starting from the early Eocene, which suggests poleward migration of the SH westerlies. This long‐term trend is punctuated by short‐lived events of aridification during the Mid‐Paleocene Biotic Event and wetter intervals during the Paleocene‐Eocene Thermal Maximum, indicating additional short‐term meridional shifting of the westerlies. We propose that the evolution of SH westerlies was driven by the equator‐to‐pole temperature gradient regulated by global warming and ephemeral growth of the Antarctic ice sheet. Plain Language Summary: The Southern Hemisphere (SH) westerlies, which are the dominant atmospheric circulation patterns in the middle latitudes, play a key role in regulating global and regional climate. Currently, the knowledge of past changes in SH westerlies relies mainly on the late Quaternary. Its dynamics over longer timescales, especially under early Cenozoic greenhouse climate states, remain poorly understood. The Mentelle Basin off southwest Australia was located at a more southerly location than at the present day, and was potentially under the influence of SH westerlies. To examine the long‐term hydroclimate changes in southwest Australia during the mid‐late Paleocene to the early Eocene (62–51 Ma), we measured neodymium and hafnium isotopic compositions of fine‐grained detrital sediments from a borehole (IODP Site U1514) drilled in the Mentelle Basin, in addition to clay mineralogy, and elemental abundances. Our results suggest a gradual wetting of southwest Australia since the early Eocene, which we relate to the poleward migration of SH westerlies in response to a reduced latitudinal temperature gradient. An abrupt northward shift of SH westerlies was observed during the short‐lived Middle Paleocene Biotic Event (∼59 Ma), possibly driven by ephemeral growth of the Antarctica ice sheet. Key Points: We reconstruct the hydroclimate evolution of southwest Australia during 62–51 MaThe Southern Hemisphere (SH) westerlies remained relatively stable during the mid‐late Paleocene and shifted poleward since the early EoceneProcesses related to variations of pole‐equator temperature gradients drove meridional migration of the SH westerlies [ABSTRACT FROM AUTHOR]

Mammals influence nearly all aspects of energy flow and habitat structure in modern terrestrial ecosystems. However, anthropogenic effects have probably altered mammalian community structure, raising the question of how past perturbations have done so. We used functional diversity (FD) to describe how the structure of North American mammal palaeocommunities changed over the past 66 Ma, an interval spanning the radiation following the K/Pg and several subsequent environmental disruptions including the Palaeocene–Eocene Thermal Maximum (PETM), the expansion of grassland, and the onset of Pleistocene glaciation. For 264 fossil communities, we examined three aspects of ecological function: functional evenness, functional richness and functional divergence. We found that shifts in FD were associated with major ecological and environmental transitions. All three measures of FD increased immediately following the extinction of the non-avian dinosaurs, suggesting that high degrees of ecological disturbance can lead to synchronous responses both locally and continentally. Otherwise, the components of FD were decoupled and responded differently to environmental changes over the last ~56 Myr. [ABSTRACT FROM AUTHOR]

Elektrocateres rappsilberi gen. et sp. nov. is described from Bitterfeld or Saxonian amber. It is the first representative of the superfamily Cleroidea (Coleoptera) recorded in this amber, from which only 10 families of beetles were known until now. The new genus and species was studied using classical stereomicroscopy, as well as digital microscopy and synchrotron-radiation-based micro-computed tomography. The fossil is related to the rare extant monotypic genera Trichocateres Kolibáč, 2010 and Carinicateres Kolibáč, 2021 from tropical forests of Southeastern Asia. It is assumed that Elektrocateres rappsilberi gen. et sp. nov. would be predatory, hunting other arthropods on tree branches and trunks; however, its mouthparts are probably still on halfway between herbivory or fungivory and predatory. [ABSTRACT FROM AUTHOR]

Source‐to‐sink dynamics are subjected to complex interactions between erosion, sediment transfer and deposition, particularly in an evolving tectonic and climatic setting. Here we use stratigraphic forward modelling (SFM) to predict the basin‐fill architecture of a multi‐source‐to‐sink system based on a state‐of‐the‐art numerical approach. The modelling processes consider key source‐to‐sink parameters such as water discharge, sediment load and grain size to simulate various sedimentary processes and transport mechanisms reflecting the dynamic interplay between erosion in the catchment area, subsidence, deposition and filling of the basin. The Cenozoic succession along the SW Barents Shelf margin provides a key area to examine controls on source‐to‐sink systems along a transform margin that developed during the opening of the North Atlantic when Greenland and Eurasian plates were separated (ca. 55 Ma onwards). Moreover, the gradual cooling which culminated in major glaciations in the northern hemisphere during the Quaternary (ca. 2.7 Ma), has affected the spatio‐temporal evolution of the sediment routing along the western Barents Shelf margin. This study aims to characterize the relative importance of different source areas within the source‐to‐sink framework through SFM. In the early Eocene, the SW Barents Shelf experienced a relatively equal sediment delivery from three principal source areas: (i) Greenland to the north, (ii) the Stappen High to the east, representing a local source terrain, and (iii) a major southern source (Fennoscandia). In the middle Eocene, our best‐fit modelling scenario suggests that the northern and the local eastern sources dominated over the southern source, collectively supplying large amounts of sand into the basin as evidenced by the submarine fans in Sørvestsnaget Basin. In the Oligocene (ca. 33 Ma) and Miocene (ca. 23 Ma), significant amounts of sediments were sourced from the east due to shelf‐wide uplift. Finally, this study highlights the dynamic nature and controls of sediment transfer in multi‐source‐to‐sink systems and demonstrates the potential of SFM to unravel tectonic and climatic signals in the stratigraphic record. [ABSTRACT FROM AUTHOR]

Atlantoceratodus iheringi (Ameghino, 1898) from Argentine territory is restudied based on its known tooth plates and newly discovered material, which includes previously unknown skull roof bones and vomerine tooth plates. The latter represent the first records of such elements from the Mesozoic era in South America. The comparative morphological analysis reveals its distinctiveness from other dipnoans, and offers valuable data for future systematic and phylogenetic research. The pterygopalatine tooth plates display narrow-based first denticulations and lack anterior wear facets, with the inner angle positioned at the level of the second denticulation. Similarly, the prearticular tooth plates feature straight mediolingual edges, and a wide-based first denticulation without sinuosities at the tip. Histological sections are performed and analyzed in detail for the first time. A. iheringi presents in this aspect distinctive features such as: large-lumen denteons tending to cluster together, circumdenteonal dentine arranged in a double band (an inner birefringent and an outer monorefringent), and a disordered interdenteonal dentine, with birefringence surrounding denteons and areas with monorefringence. A. iheringi exhibits histological structure closer to Mesozoic and Cenozoic dipnoans than Paleozoic, especially resembling the disposition observed in the Upper Cretaceous Patagonian species Metaceratodus baibianorum. The wide distribution of features designated as diagnostic for Atlantoceratodus is discussed. [ABSTRACT FROM AUTHOR]

Here, we studied several Pachyrukhinae (Mammalia: Notoungulata: Typotheria: Hegetotheriidae) fossils recovered from the late Early Miocene (Santacrucian SALMA) beds of the Cura-Mallín Formation at the Laguna del Laja (Biobío Region, Chile). The specimens are referred to a new species of the genus Pachyrukhos Ameghino, 1885, P. ngenwinkul sp. nov. The holotype of this taxon is a relatively well-preserved articulated skull and mandibles, which was investigated using 3D X-ray Microscopy. The new taxon is distinguished from other Pachyrukhos species by having a p2 smaller than p3, M3 mesiodistally shorter (around 30%) than M1, and upper premolars of a rather subtriangular contour. Pachyrukhos ngenwinkul is the most common mammal and the smallest-sized (with ~2 kg of body mass) notoungulate found in the Santacrucian assemblage at the Laguna del Laja. The discovery of this new taxon improves our understanding of the Neogene pachyrukhine diversity in southern South America and highlights the potential of the Chilean Andean Cenozoic deposits in revealing a hidden diversity of extinct continental mammals. [ABSTRACT FROM AUTHOR]

Summary: Angiosperm fossil woods of putative Eocene age from Corcovado, Chubut Province are described. They are placed in four taxonomic units: Weinmannioxylon trichospermoides and cf. Caldcluvioxylon of the Cunoniaceae, Myrceugenellites maytenoides of the Myrtaceae, and Nothofagoxylon ruei of the Nothofagaceae. The taxa in the assemblage are in accordance with similar fossil wood assemblages previously described from the Eocene and Oligocene of Patagonia. All the taxa are anatomically similar to trees that live today in Patagonia. Some of the woods show decay patterns by different saproxylic organisms. These include arthropod borings with coprolites and fungal remains in fungi-decayed tissues that are consistent with an active saproxylic community involved in the recycling of wood in the depositional paleoenvironment. [ABSTRACT FROM AUTHOR]

The Cenozoic stratigraphy of the Zagros records the ongoing collision between the Arabian and Eurasian Plates and the closure of NeoTethys. A Paleogene NW‐SE trending foreland basin was inherited from a Late Cretaceous precursor. Widespread progradation into the foredeep was a feature of both margins which, allied to ongoing tectonism, had by the late Eocene led to the narrowing and subsequent division of the foredeep into the Lurestan – Khuzestan and Lengeh Troughs, separated by the northward continuation of the rejuvenated Qatar‐Fars Arch. This sub‐division strongly influenced subsequent deposition and the petroleum geology of the area. In addition, the diachronous nature of the Arabian – Eurasian collision led to strong diachroneity in lithostratigraphic units along the length of the Zagros. Hence its petroleum geology is best understood within a regional sequence stratigraphic framework. This study identifies three tectono‐megasequences (TMS 10, TMS 11a, TMS 11b) and multiple depositional sequences. The Cenozoic contains a world class hydrocarbon province with prolific oil reservoirs in the Oligo‐Miocene Asmari Formation sealed by the evaporite‐dominated Gachsaran Formation, mostly contained within giant NW‐SE trending "whaleback" anticlines concentrated in the Dezful Embayment. Reservoirs in the SW are dominantly siliciclastic or comprise mixed siliciclastics and carbonates, whereas those to the east and NE are dominated by fractured carbonates. There remains untested potential in stratigraphic traps, especially in deeperwater sandstone reservoirs deposited along the SW margin of the foredeep. Late Miocene to Pliocene charge to the Asmari reservoirs was mostly from Aptian – Albian Kazhdumi Formation source rocks. In some fields, an additional component was from organic‐rich late Eocene to earliest Oligocene Pabdeh Formation source rocks confined to the narrowing Lurestan – Khuzestan Trough. Where mature, the latter source rock is also a potential unconventional reservoir target, although the prospective area is limited due to recent uplift and erosion. Deeper Jurassic source rocks contributed to the Cheshmeh Khush field in Dezful North. Silurian source rocks charged gas‐bearing structures in the Bandar Abbas region. [ABSTRACT FROM AUTHOR]

The mechanisms by which complex intracontinental deformation in the northern Tibetan Plateau was accommodated since the India-Asia collision remain debated. Characterization of the formation of arcuate structures in northern Tibet provides important constraints on this debate. We conducted a new paleomagnetic study on the mid- to late Miocene strata along the curved Lenghu-Nanbaxian and Eboliang-Hulushan belts of the Qaidam Basin, northern Tibet. Our results revealed that there is nonsignificant relative rotation within localities along these arcuate belts, which yielded a common mean direction of declination (D) = 3.6°, inclination (I) = 35.7° (a95 = 2.4°) after tilt correction, suggesting negligible Neogene verticalaxis rotation along the arcuate belts in the Qaidam Basin. Outcropped fault striations and the positive flower structures indicate dextral strike-slip-dominated motion along the faults since the mid- to late Miocene. By integrating the paleomagnetic results with the kinematics of these associated faults, we ruled out the possibility that these curved belts formed due to the frictional drag of the Altyn Tagh fault or due to differential shortening across the Qaidam Basin. Instead, we attribute the formation of these nonrotational arcuate belts to dextral transpressional deformation occurring within the basin since the mid- to late Miocene. Different from the orogenic belts in the northern Tibetan Plateau that absorbed postcollisional conver convergence through block rotation, crustal shortening, and lateral extrusion, the Qaidam Basin has also accommodated significant intracontinental deformation in the northern Tibetan Plateau through transpressional deformation within the basin. This inference underscores the importance of recognizing crustal extrusion within rigid blocks as a record of intracontinental deformation in the northern Tibetan Plateau. [ABSTRACT FROM AUTHOR]

The tectonics and landscape of SE China experienced significant changes throughout the Mesozoic and early Cenozoic, largely in response to variations in the slab dynamics of the paleo-Pacific plate, which was subducting beneath continental Asia. We investigated the Mesozoic Yong'an basin in western Fujian Province of SE China in comparison to the sedimentary records of coeval basins in the region to document how its clastic sediment types and their provenance varied through time during the Mesozoic and what regional geologic processes may have controlled these variations. The average eNd value of samples from the Middle Jurassic Zhangping Formation is -16.6, and its detrital zircons are dominated by 1800 Ma and 2000 Ma grains, sourced from the northern Wuyishan Mountains. These mountains underwent significant rock and surface uplift by the Middle Jurassic and became the main source of clastic sediments in SE China. The Lower Cretaceous Bantou Formation contains pyroclastic rocks and represents fluvial-lacustrine deposits with eNd values of -14.8 to -12.4 and abundant 160-120 Ma detrital zircons, sourced from Late Jurassic granitoid rocks, which were widely exposed at the surface in SE China by this time. The upper Lower and lower Upper Cretaceous Shaxian Formation contains coarse-grained and poorly sorted sandstones-conglomerates with volcanic and granitic rock fragments, and it rests unconformably on the Bantou Formation. The Shaxian Formation represents fluvial- to alluvial-fan deposits, and its formation marks the timing of a rapid uplift of the paleo-Coastal Mountains. The Upper Cretaceous Chong'an Formation (>2000 m thick) contains abundant volcanic and granitic rock clasts and represents alluvial-fan and fluvial deposits. The average eNd values of the Shaxian and Chong'an Formations range between -9.3 and -7.5, and their most abundant detrital zircon ages are between 120 Ma and 80 Ma. By the end of the Late Cretaceous, the paleo-Coastal Mountains constituted a nearly 4-km-high magmatic belt, with much of SE China situated in its rain shadow at a lower elevation to the north. Eocene-Oligocene sedimentary basin rocks in Taiwan have an average eNd value of -10.9 and abundant Phanerozoic detrital zircons. The sediment source for these rocks was the paleo-Coastal Mountains. The Miocene basinal strata in Taiwan have more negative eNd values (-13.0) and contain Jurassic-Cretaceous as well as abundant Paleoproterozoic and Neoproterozoic zircons, indicating that the Wuyishan Mountains were again the main sediment source later in the Cenozoic. Denudation rates in the SE margin of South China were high (0.12-0.10 km/yr) during the Cretaceous (140-60 Ma), while they were very low in SW China and in the interior of South China during the same period. These differences confirm the existence of high coastal mountains in SE China until the Late Cretaceous. Denudation rates in eastern South China, particularly the coastal areas, were very low (0.06-0.02 km/yr) during the late Cenozoic (30-0 Ma), whereas they were the fastest (0.14-0.16 km/yr) in the northern Nanling belt and the Yangtze block farther inland to the north, indicating the surface elevation became higher in the western part of South China but lower in its eastern part in the late Cenozoic. This dynamic landscape evolution of SE China through multiple and major shifts throughout the Mesozoic and early Cenozoic was driven by the subducting slab dynamics and the tectonics of the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

For sedinentary archives to be used as a record of hinterland evolution, the factors affecting the archive nust be known. In addition to tectonics, a nunber of factors, such as changes in clinate and paleodrainage, as well as the degree of diagenesis, influence basin sedinents. The Indus River delta-fan systen of South-Central Asia records a history of Hinalayan evolution, and both the onshore and offshore sedinentary repositories have been studied extensively to research orogenesis. However, a nunber of unknowns renain regarding this systen. This paper seeks to elucidate the paleodrainage of the Indus River, in particular when it took on its nodern drainage configuration with respect to conjoinnent of the nain Hinalayan (Punjabi) tributary systen with the Indus trunk river. We leverage the fact that the Punjabi tributary systen has a significantly different provenance signature than the nain trunk Indus River, draining nainly the Indian plate. Therefore, after the Punjabi tributary systen joined the Indus River, the proportion of Indian plate naterial in the repositories downstrean of the confluence should have been higher than in the upstrean repository. We conpared bulk Sr-Nd data and detrital zircon U-Pb data fron the Cenozoic upstrean peripheral foreland basin and downstrean Indus delta and Indus Fan repositories. We deternined that throughout Neogene tines, repositories below the confluence had a higher proportion of naterial fron the Indian plate than those above the confluence. Therefore, we conclude that the Indus River took on its current configuration, with the Punjabi tributary systen draining into the Indus trunk river in the Paleogene, early in the history of the orogen. The exact tine when the tributary systen joined the Indus should correlate with a shift to nore Indian plate input in the down-strean repositories only. While the upstrean repository records no change in Indian plate input fron Eocene to Neogene tines, a shift to increased naterial fron the Indian plate occurs at the Eocene-Oligocene boundary in the delta, but sonetine between 50 Ma and 40 Ma in the fan. Though further work is required to understand the discrepancy between the two downstrean repositories, we can conclude that the tributary systen joined the Indus trunk river at or before the start of the Oligocene. [ABSTRACT FROM AUTHOR]

The causal relationship between the activity of mantle plumes and continental break-up is still elusive. The Afro-Arabian rift system offers an opportunity to examine these relationships, in which an ongoing continental break-up intersects a large Cenozoic plume-related flood basalt series. In the Afar region, the Gulf of Aden, the Red Sea, and the Main Ethiopian Rift form an R-R-R triple junction within plume-related flood basalt series. We provide an up-to-date synthesis of the available geophysical and geological data from this region. We map the rift architecture in the intersection region by applying the difference in Gaussians to the topography and the bathymetry and interpreting vertical gravity gradients and Bouguer anomalies. With the aid of these methods we review the spatiotemporal constraints in the evolution of the different features of the plume–rift system. Our results show rough and irregular morphologies of the Gulf of Aden and the Red Sea arms in contrast to the symmetric, continuous, and smooth Main Ethiopian Rift. The triple junction formed by the northeastward propagation of the Main Ethiopian Rift and developed simultaneously with the abandonment of the tectonic connection between the Red Sea and the Gulf of Aden through Bab al Mandab Strait. The triple junction was the last feature to develop in the plume–rift system and marked a tectonic reorganization. By this time, all rift arms were sufficiently evolved and the break-up between Africa and Arabia was already accomplished. We argue that the classical active and passive rifting mechanisms cannot simply explain the progressive development of the Afro-Arabian rift. Instead, we propose a plume-induced plate rotation, which includes an interaction between active and passive mechanisms. In this tectonic scenario, the arrival of the Afar plume provided a push force that promoted the rotation of Arabia around a nearby pole located to the northwest of the plate boundary, enabling the rifting and, ultimately, the break-up of Arabia from Africa. [ABSTRACT FROM AUTHOR]

In the southeastern Tibetan Plateau, region‐scale dextral strike‐slip shear zones, crucial for India‐Asia convergence, were investigated along the Dulongjiang shear zone near the Eastern Himalayan Syntaxis (EHS). Structural, kinematic, and geochronological data from Dulongjiang and Nabang regions in western Yunnan, China, reveal dextral strike‐slip shearing between 30 and 15 Ma. Various rocks were affected by moderate‐temperature shear deformation (∼450–550°C), inferred from microstructures and quartz CPO patterns, during dextral strike‐slip and exhumation of the shear zone. Combined with structures of pre‐, syn‐, and post‐shearing leucogranites, zircon U‐Pb dating indicates that the dextral shear along the shear zone began in the Early Oligocene (30–29 Ma) subsequent to the India‐Asia collision. Micas in mylonitic granites yield 40Ar/39Ar ages, suggesting that the principal dextral shear deformation occurred approximately between 18 and 15 Ma. The Dulongjiang shear zone is linked to the Parlung, Nabang shear zone, and Sagaing Fault, forming a regional Cenozoic dextral shear system around the EHS. The study, combined with tomographic anomalies beneath the India‐Asia collision zone, highlights distinct lithospheric‐scale evolution in southeastern and eastern Tibet. Continuous intracontinental strike‐slip shearing indicates a tectonic shift from Tibetan extension to block rotation around the EHS. From 30 to 15 Ma, slab tear, accompanied by clockwise rotation and dextral strike‐slip shearing, suggests a warmer geodynamic setting influenced by hot mantle flow associated with ongoing subduction of the Indian lithosphere. Oligocene‐Miocene dextral strike‐slip shearing around the EHS, linking southwards with the Sagaing Fault, may correspond to the rotation necessary for slab to bend, stretch, and eventually tear beneath the region. Plain Language Summary: The southeastern Tibetan Plateau undergoes active southeastward extrusion and rotation around the Eastern Himalayan Syntaxis (EHS) due to ongoing Indo‐Eurasian continent collision. N‐S, NW‐SE, and NE‐SW ductile strike‐slip shear zones/faults in Tibet and the Indochina Block reveal this tectonic activity. Understanding their kinematics, linkages, and developmental patterns is crucial for investigating the relationship between Cenozoic surface tectonics and Tibetan Plateau lithospheric evolution. This study focuses on the Jiali‐Dulongjiang‐Nabang dextral (relative rightward movement on both sides of the fault) strike‐slip ductile shear zone/fault system, revealing a curved regional‐scale dextral strike‐slip zone system influenced by continuum rotation deformation, driven by slab tear beneath the EHS region. Contrary to the concept of a conjugated strike‐slip shear/fault system dominating extension tectonics, these findings suggest a significant influence of continuum rotation deformation on the initiation, movement, and linkage of curved dextral strike‐slip shearing around the EHS. Key Points: A network of dextral strike‐slip shear zones formed a regional curved belt around the Eastern Himalayan Syntaxis from ∼30 to ∼15 MaSlab tear beneath the Eastern Himalayan Syntaxis induced unique asthenospheric flow pattern, causing the bending and interconnection of dextral shear zonesThe V‐shaped conjugate shear zones are related to indent‐driven system, marking northward penetration of the Indian plate into Eurasia [ABSTRACT FROM AUTHOR]

The Ordos block is an important active block in North China during the Cenozoic and modern tectonic activity. Based on a large amount of GPS observation data, an accurate and dense GPS velocity field of the Ordos block is calculated through frame transformation. The results indicate that the estimated internal principal tensile and compressive strain rates of the Ordos block are 2.7 10-9/yr and 1.510-9/yr, respectively. Additionally, the block exhibits rigidity and there is negligible counterclockwise rotation. Relative to the Ordos Basin, the Loop Fault on the north side of the Ordos Block displays a left-rotation strike-slip rate of approximately 0.9 mm/yr and a dip-slip rate of around 0.5 mm/yr, accompanied by slight extrusion. The dip slip rate of the southern section of Taihang Mountain fault system indicates that there is spreading movement in the southeastern part of the block. The southwestern Liupanshan fault also experiences extrusive motion. These block motion features and fault sliding distributions provide a reliable database for understanding the possible motion and dynamics mechanisms of the Ordos region. [ABSTRACT FROM AUTHOR]

The article presents a comparative analysis of the Paleozoic and Cenozoic reef formation, mainly in terms of the position of reefs in the basins of continental and oceanic blocks. It is shown that the main formation of reefs took place in the Cenozoic directly in the oceans, including boundaries between oceans and continents, and, to an extremely limited scales, in the basins of the continental segment. In the Paleozoic, reefs were formed not only in oceans, but also in spacious basins of continental block. This is one of the manifestations of the general evolution of carbonate accumulation, when the Paleozoic carbonate sediments were formed in such shallow-water bodies that covered very significant surfaces of continents. [ABSTRACT FROM AUTHOR]

The fossil record of the genus Carcharodon (Lamniformes: Lamnidae) dates to the late Oligocene and has a near global distribution. Today the genus is represented by a single species, the white shark Carcharodon carcharias. However, multiple extinct species are recognised in the Cenozoic including Carcharodon hastalis, Carcharodon hubbelli and Carcharodon planus comb. nov. Here we present the first occurrences of Carcharodon hubbelli and Carcharodon planus from New Zealand/Aotearoa, from the South Island/Te Waipounamu. Carcharodon hubbelli is previously reported from late Miocene deposits in the Pacific basin of North and South America, Asia, and Australia. Whereas Carcharodon planus has been reported from the Miocene of North America and Asia. One tooth from Carcharodon hubbelli is reported from the presumed late Miocene of Motunau Beach, North Canterbury, while one upper early Miocene tooth recovered from the Kakahu River, South Canterbury and an earliest Miocene tooth from the Big River mouth, Tasman District are referred to Carcharodon planus. In addition to being the first reported occurrences of these two species in New Zealand, the teeth of Carcharodon planus represent some of the earliest occurrences of the taxon as well as its southernmost occurrence. [ABSTRACT FROM AUTHOR]

Albatrosses are among the most intensely studied groups of living birds, yet their fossil record remains sparse. Despite modern albatrosses being more abundant and widespread in the Southern Hemisphere, the vast majority of fossil albatrosses identified to date come from Northern Hemisphere localities. Here, we describe Plotornis archaeonautes sp. nov., a new albatross species from the earliest Miocene that represents the earliest record of Procellariiformes in New Zealand and the earliest uncontroversial record of the clade Pan-Diomedeidae from the Southern Hemisphere. Phylogenetic analyses support the placement of Plotornis outside of the clade uniting all extant albatrosses. The new fossil reveals that stem lineage albatrosses were widespread by the onset of the Neogene. Although the humerus of Plotornis archaeonautes exhibits a short processus supracondylaris dorsalis, this early species may have possessed at least one of the unique ossifications associated with the patagial bracing system present in modern albatrosses. [ABSTRACT FROM AUTHOR]

We obtain three‐dimensional models of crustal shear‐wave velocity and radial anisotropy in the Bohai Bay basin (BBB), revealing distinct radial anisotropy patterns. The western region of the basin exhibits pronounced positive crustal radial anisotropies, attributed to upper mantle convection driven by the subduction of the Pacific plate during the early Tertiary. Conversely, the eastern region of the basin demonstrates weak to negative radial anisotropies, indicating a compression shear rupture system influenced by the far‐field India‐Eurasian collision during the Neogene‐Quaternary. These differences suggest that the formation of the BBB is associated with the dynamic transition from Pacific subduction to India‐Eurasian collision during the Cenozoic. Moreover, the Luxi uplift, with its stable upper‐middle crustal structures, acts as a barrier hindering the eastward extension of the BBB. Plain Language Summary: As the largest Meso‐Cenozoic basin in Eastern China, the Bohai Bay basin (BBB) is an ideal site for studying basin evolution. However, the tectonic processes within the basin during the Cenozoic remain largely enigmatic. Seismic radial anisotropy, indicative of subhorizontal layering and/or shearing during crustal/lithospheric accretion, can offer valuable insights into Earth's dynamic processes. In this study, we use a direct inversion method called DRadiSurfTomo to create high‐resolution three‐dimensional models of shear‐wave velocity and radial anisotropy in the BBB. Our findings indicate that current crustal radial anisotropy patterns in the basin reflect multiple dynamic stages since the Cenozoic. The strong positive radial anisotropy observed in the western BBB is primarily due to the subduction of the Pacific plate, whereas the weak radial anisotropy in the eastern BBB is mainly influenced by tension‐shear forces resulting from the India‐Eurasian collision. We also infer that the high shear‐wave velocity and negative radial anisotropy in the upper‐middle crust of the Luxi uplift are likely induced by rigid metamorphic rocks, hindering the basin's eastward expansion. Key Points: Low velocity anomalies observed in the mid‐to lower crust of the Bohai Sea is attributed to the presence of felsic materialsThe Cenozoic evolution of Bohai Bay basin (BBB) is related to the tectonic transition from Pacific subduction to India‐Eurasian collisionLuxi uplift acts as an obstruction, impeding the extension of the upper‐middle crust in the BBB [ABSTRACT FROM AUTHOR]

South America underwent a span of isolation in the Cenozoic, during which an endemic fauna developed, including a diverse group of native ungulates. Among them, Proterotheriidae (Litopterna, Pan-Perissodactyla) were small to medium-sized hoofed herbivores mainly documented from the Oligocene to the Pleistocene. The study of proterotheriid mammals, specifically their cranial morphology, has been challenging due to the limited availability of materials, leading to a heavy reliance on dental evidence in their descriptions. This issue is particularly evident for late Neogene records, where comprehensive cranial studies have been lacking. Herein, we study a juvenile proterotheriid individual referred to Neobrachytherium intermedium recovered from Early Pliocene outcrops of northwestern Argentina. Our research focuses on cranial morphology, particularly on the dorsal and orbitotemporal regions, mesocranium, and basicranial structures. By employing noninvasive techniques, we describe the petrosal anatomy and compare it in a broader phylogenetic context. We also provide insights into ontogenetic stages within the genus. We find singular arrangements and structures for the genus (e.g., tuberosities in the postglenoid process) as well as traits shared with other mammals that are distinct from those found in other SANUs and pan-perissodactyls, such as Notoungulata (e.g., ringlike ectotympanic, gracile tympanohyal, poorly developed epitympanic wing and medial flange, large hiatus Fallopii). Traits such as the position and shape of the m. tensor tympani fossa and the development of the jugular notch may be synapomorphies of Litopterna, but this cannot be determined without resolving the phylogenetic position of Indalecia grandensis, which has been suggested to be a basal Litopterna. Considering ontogenetic observations, features like the frontal sulcus, the supraorbital foramen, and the palate configuration exhibit age-related changes. The occlusal patterns of teeth undergo substantial changes with wear, affecting loph morphology. Variations in deciduous premolars are observed within the same individual. These findings emphasize the importance of considering ontogenetic and individual variations when analyzing cranial and dental remains for taxonomic and phylogenetic purposes. The study provides valuable information for understanding late Neogene proterotheriids and the broader context of cranial evolution within Litopterna, highlighting the necessity for more comprehensive research. [ABSTRACT FROM AUTHOR]

Antifreeze proteins (AFPs) are found in a variety of marine cold‐water fishes where they prevent freezing by binding to nascent ice crystals. Their diversity (types I, II, III and antifreeze glycoproteins), as well as their scattered taxonomic distribution hint at their complex evolutionary history. In particular, type I AFPs appear to have arisen in response to the Late Cenozoic Ice Age that began ~ 34 million years ago via convergence in four different groups of fish that diverged from lineages lacking this AFP. The progenitor of the alanine‐rich α‐helical type I AFPs of sculpins has now been identified as lunapark, an integral membrane protein of the endoplasmic reticulum. Following gene duplication and loss of all but three of the 15 exons, the final exon, which encoded a glutamate‐ and glutamine‐rich segment, was converted to an alanine‐rich sequence by a combination of frameshifting and mutation. Subsequent gene duplications produced numerous isoforms falling into four distinct groups. The origin of the flounder type I AFP is quite different. Here, a small segment from the original antiviral protein gene was amplified and the rest of the coding sequence was lost, while the gene structure was largely retained. The independent origins of type I AFPs with up to 83% sequence identity in flounder and sculpin demonstrate strong convergent selection at the level of protein sequence for alanine‐rich single alpha helices that bind to ice. Recent acquisition of these AFPs has allowed sculpins to occupy icy seawater niches with reduced competition and predation from other teleost species. [ABSTRACT FROM AUTHOR]

The long-trunked elephantids underwent a significant evolutionary stage characterized by an exceptionally elongated mandible. The initial elongation and subsequent regression of the long mandible, along with its co-evolution with the trunk, present an intriguing issue that remains incompletely understood. Through comparative functional and eco-morphological investigations, as well as feeding preference analysis, we reconstructed the feeding behavior of major groups of longirostrine elephantiforms. In the Platybelodon clade, the rapid evolutionary changes observed in the narial region, strongly correlated with mandible and tusk characteristics, suggest a crucial evolutionary transition where feeding function shifted from the mandible to the trunk, allowing proboscideans to expand their niches to more open regions. This functional shift further resulted in elephantids relying solely on their trunks for feeding. Our research provides insights into how unique environmental pressures shape the extreme evolution of organs, particularly in large mammals that developed various peculiar adaptations during the late Cenozoic global cooling trends. [ABSTRACT FROM AUTHOR]