Earth-Science Reviews最新文献

{"title":"Wind erosion in northern China: Insights from the western Qaidam fold belt, Loess Plateau, and Hami Basin","authors":"Paul Kapp , Alex Pullen , Jordan T. Abell , Liyun Zhang","doi":"10.1016/j.earscirev.2024.105037","DOIUrl":"10.1016/j.earscirev.2024.105037","url":null,"abstract":"<div><div>Pliocene – Quaternary wind erosion profoundly modified the physiography of northern China at a large range of spatial (10 m to >100 km) and temporal (10 ka to Myr) scales. In the western Qaidam Basin along the northeastern margin of the Tibetan Plateau, northwesterly winds sculpted yardangs in actively folding Miocene – Pleistocene strata. Wind erosion was most dominant during glacial periods, whereas lacustrine deposition was more extensive during warmer and wetter interglacial periods. Cyclical wind erosion and sedimentation is recorded by paleoyardangs in Pliocene – Pleistocene strata. A thickness of hundreds to thousands of meters of strata has been blown off the crests of Qaidam anticlines. Wind erosion initiated at ∼3 Ma and increased in spatial extent and magnitude from early to late Pleistocene time as aridity intensified and strata were tectonically uplifted. Qaidam anticlines are propagating in the windward direction and accelerated in growth concomitant with wind erosion, raising the possibility that spatially variable removal of mass by wind influenced the rates and kinematics of deformation. To the east of Qaidam Basin is the Chinese Loess Plateau. The northern, windward margin of the central Loess Plateau is an up to 400-m-high erosional escarpment made of loess that slopes northward into the wind-eroded and endorheic Mu Us Desert. During Pleistocene aridification and expansion of the Mu Us Desert, the Loess Plateau escarpment margin retreated as it was wind eroded while loess continued to accumulate downwind and further build the plateau. The Hami Basin within the eastern Tian Shan of northwestern China is one of the windiest regions on Earth today and part of the broader Gobi Desert that extends eastward into Mongolia. In the north-central Hami Basin, northerly winds sculpted yardangs in Cretaceous strata and have blown a thickness of ≥200 m of Cretaceous – Pleistocene strata out of the closed basin. Wind erosion of northern Hami Pleistocene alluvial deposits led to the widespread development of unconsolidated gravel deposits and pavements. These gravels armor underlying alluvial strata from further wind erosion and thereby suppress dust emissions, despite extreme winds. The Hami and other Gobi Desert basins may have experienced an overall decrease in dust emissions from Pliocene to late Pleistocene time as the volume of silt-bearing strata decreased in the basins while the area of the basins armored by gravel increased. Structural unloading joints in some Hami yardang fields accelerate rates of wind erosion and yardang demise, and their wind-parallel orientation provides another potential example of an interplay between wind erosion and rock deformation. This review suggests that the sources and fluxes of Asian dust were not spatially uniform through the Neogene and Quaternary. The geological and topographic history, landscape evolution, and short- and long-term climate variations in Asia all need to be simultaneousl","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"261 ","pages":"Article 105037"},"PeriodicalIF":10.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143136872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Natural records of supercritical fluids in subduction zones","authors":"Yang-Yang Wang ,&nbsp;Yilin Xiao ,&nbsp;Ren-Xu Chen ,&nbsp;Yi-Xiang Chen ,&nbsp;Ji-Lei Li ,&nbsp;Shun Guo","doi":"10.1016/j.earscirev.2024.105031","DOIUrl":"10.1016/j.earscirev.2024.105031","url":null,"abstract":"<div><div>A supercritical fluid (SCF) in a silicate-H₂O system was generally regarded as a homogeneous phase formed under pressure and temperature (P-T) conditions higher than the second critical endpoint of the system. It evolves into a hydrous melt and aqueous fluid with decreasing P-T conditions or after interactions with wall rocks during fluid migration. Subduction zones are preferable sites for seeking records of SCFs in the natural systems, particularly when the P-T paths of the rocks cross through the stability area of the SCFs. This contribution first defines SCF by considering the homogeneous fluid above the critical curve of the corresponding rock–H₂O system as a generalized SCF and then reviews the recent advances about the natural records of SCFs in subduction zones. Specifically, multiphase inclusions are the most direct proxy for SCF with both fluid-bearing and fluid-free ones containing complex mineral associations being probably linked to SCFs. The major element composition of the SCF recovered from multiphase inclusions is broadly consistent with the experimental data, showing an intermediate composition between the aqueous fluid and hydrous melt. The SCF-associated element transportation can be determined in ultrahigh pressure veins, accessory minerals, and mantle wedges, mostly based on the strong capability of SCFs to transport high field strength elements and heavy rare earth elements. The phase separation of SCF is widespread, including both microscale evidence of inclusions and macroscale evidence of composite veins as well as concurrent signals of fluid and melt metasomatism in the mantle wedge. Isotopic fractionations associated with SCFs have been reported intermittently. However, it mainly depends on the isotope composition of source rock and the dissolving capacity of the SCF. Finally, we propose certain identification criteria of SCF relative to aqueous fluid and hydrous melt by integrating the published data, including specific multiphase inclusion signatures; major element ratios of CaO/Al₂O₃ (fluid/source rock) ≥ 1.15, FeO/Al₂O₃ (fluid/source rock) ≥ 0.5, and MgO/Al₂O₃ (fluid/source rock) ≥ 0.6; and large Nb<img>Ta fractionation. Other signatures of SCFs, such as high sulfur content and abnormal Fe-Mg-Cr-O-S isotope compositions, also display potential. However, further studies are required to validate these.</div></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"261 ","pages":"Article 105031"},"PeriodicalIF":10.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Traversing the rift: A review of the evolution of the West and Central African Rift System and its economic potential","authors":"Nils Lenhardt ,&nbsp;Erepamo J. Omietimi ,&nbsp;Aitalokhai J. Edegbai ,&nbsp;Lorenz Schwark ,&nbsp;Octavian Catuneanu ,&nbsp;James D. Fairhead ,&nbsp;Annette E. Götz","doi":"10.1016/j.earscirev.2024.104999","DOIUrl":"10.1016/j.earscirev.2024.104999","url":null,"abstract":"<div><div>The Cretaceous to recent West and Central African Rift System is a major geological feature in Africa, extending 4000 km from the west to the east. Its formation is related to the breakup of Gondwana and the separation of Africa from South America, during which a complex network of extensional, wrench and pull-apart basins formed. These basins can be separated into two coeval rift sub-systems, the West African Rift System and the Central African Rift System. Both systems are genetically related but are physically separated and show significant structural as well as sedimentological differences. However, despite its great importance for the history of the African continent, our understanding of its origins and evolution is limited due to a scarcity of geophysical and sedimentological data. In this review paper, we examine the sedimentary and igneous basin-fill of the major West and Central African Rift System basins using literature data from the previous five decades. We analyse basin evolution, sequence stratigraphy, changing environmental and palaeoclimatic conditions, and economic aspects of the basins. Furthermore, we address future needs and challenges in research and collaboration between academia and industry to better understand the vast economic potential of the West and Central African Rift System basins. Ultimately, our findings shed light on the complicated geological history of the West and Central African Rift System and offer vital insights for future research and development in the region.</div></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"261 ","pages":"Article 104999"},"PeriodicalIF":10.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143136845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Holocene extreme flood distribution patterns in the upper and middle Yellow River: A review based on slackwater deposits","authors":"Wenhua Gao ,&nbsp;Kaifeng Li ,&nbsp;Xiaodong Miao ,&nbsp;Liang Zhou","doi":"10.1016/j.earscirev.2024.105039","DOIUrl":"10.1016/j.earscirev.2024.105039","url":null,"abstract":"<div><div>Investigating the past occurrences of Yellow River floods provides essential insights into the river's natural variability and recurrent patterns over time. This historical context is indispensable for predicting and mitigating future flood events. However, comprehending the long-term variability of these extreme flood events faces challenges from the limited duration and sparse geographical distribution of gauging station records. Fortunately, flood slackwater deposits (SWDs) within the fluvial stratigraphy provide excellent records for reconstructing extreme floods beyond historical documents and modern observations. Here we scrutinize and synthesize the reported SWD records from the upper and middle Yellow River, and conduct a meta-analysis of these floods, in order to reconstruct the distribution patterns of extreme floods throughout the Holocene. 30 SWD sequences from 57 sites passed our rigorous data quality scrutiny, and subsequently total of 72 flood units (with different age-quality levels) were utilized to reconstruct the spatiotemporal distribution of Holocene extreme floods. Our results identified five extreme flood-rich periods, centered at 8500 yr BP, 6300–6100 yr BP, 4300–4000 yr BP, 3400–3000 yr BP, and 1800–1600 yr BP. The floods in these periods exhibit a significant increase in frequency and a shift in their spatial scale after ∼5000 yr BP, which are probably modulated by millennial-scale summer insolation, resulting in increased El Niño-Southern Oscillation activity and intensified latitudinal temperature gradient. Our comparison analysis between flood-rich periods and various climatic proxies suggests a centennial-scale ‘dry-cold’ climatic configuration during these periods. An anomalous low-latitude western North Pacific anticyclone, coupled with an anomalous mid-latitude cyclone-anticyclone pair, contribute to the convergence of water vapor from the western Pacific and Arctic region into northern China. This convergence led to extraordinary rainstorms and extreme floods in the upper and middle Yellow River, which significantly impact the human activity in the lower Yellow River. In addition, identifying Holocene extreme flood-rich periods and their climatic configurations offers new insights for predicting long-term extreme hydrological events in the region. Nonetheless, the uncertainty of our synthesis results owing to the limitation of currently available data should be considered and warrants verification in future studies.</div></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"261 ","pages":"Article 105039"},"PeriodicalIF":10.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143136873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Paleoclimatic significance of water isotopes in speleothem fluid inclusions","authors":"Stéphane Affolter ,&nbsp;Timon Kipfer ,&nbsp;Elisa Hofmeister ,&nbsp;Markus Leuenberger ,&nbsp;Dominik Fleitmann","doi":"10.1016/j.earscirev.2024.105026","DOIUrl":"10.1016/j.earscirev.2024.105026","url":null,"abstract":"<div><div>Speleothems (cave carbonate) contain fluid inclusions that are natural repositories of cave drip water and precipitation respectively. This water is stored within the speleothem calcite matrix and well preserved from post-depositional alterations in cave environments. Extracting the water and analysing its isotopes provide direct information about the hydrological cycle on timescales ranging from months to millions of years (&gt;10⁶ years). Therefore, speleothem fluid inclusions offer the opportunity to address key questions about paleorainfall and paleotemperatures, as water isotopes can be used to reconstruct temperatures or origin of moisture at the time of calcite deposition. This review aims to explore the background and history of speleothem fluid inclusion science and the development of analytical methods and records, thereby giving new insights into the potential of fluid inclusions. Based on a compilation of available speleothem fluid inclusion water isotopes, we developed a paleo-Global Meteoric Water Line (paleo-GMWL) that shows a similar slope to modern precipitation which corroborates the potential of fluid inclusions in the reconstruction of past precipitation. Similarly, first spatial observations seem to highlight the potential of fluid inclusions to contribute to a Global Network of Isotopes in Precipitation in the past (paleo-GNIP). Recent analytical developments will further enable the production of highly-resolved water isotope records for continental areas. Therefore, overall, there is a great potential in the use of speleothem fluid inclusions in paleoclimate sciences, which will provide information about past climate and allow data-model comparisons.</div></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"261 ","pages":"Article 105026"},"PeriodicalIF":10.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143136865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Global vegetation zonation and terrestrial climate of the warm Early Eocene","authors":"Nick Thompson ,&nbsp;Ulrich Salzmann ,&nbsp;David K. Hutchinson ,&nbsp;Stephanie L. Strother ,&nbsp;Matthew J. Pound ,&nbsp;Torsten Utescher ,&nbsp;Julia Brugger ,&nbsp;Thomas Hickler ,&nbsp;Emma P. Hocking ,&nbsp;Daniel J. Lunt","doi":"10.1016/j.earscirev.2024.105036","DOIUrl":"10.1016/j.earscirev.2024.105036","url":null,"abstract":"<div><div>The early Eocene is a key geological time interval to further our understanding of climate change and biosphere variability under high atmospheric CO₂ concentrations of more than 800 ppmv that could potentially be reached by the end of this century under very high emission scenarios. Vegetation plays a crucial role in the global carbon cycle and climate, and future warming associated with high atmospheric CO₂ will alter modern vegetation patterns and biome distribution, consequently affecting vegetation-climate feedbacks. Here we present the most comprehensive global synthesis of vegetation and quantitative terrestrial climate estimates to date, compiled for 193 palaeobotanical locations, covering the early Eocene (Ypresian; 56.0-47.8 Ma). The floristic components of these palaeofloras are translated into 41 Plant Functional Types (PFT) and statistically grouped into palaeo-biomes. In addition, we used leaf phenology and PFT percentage of shrubs and xerophytes to assess vegetation openness. Our global biome reconstruction and quantitative climate estimates show a warmer and overall wetter world with reduced latitudinal temperature gradients and highlight the importance of climate seasonality as environmental controls of early Eocene biome distribution. A comparison of proxy-based reconstructions with outputs of the vegetation model BIOME4, driven by climate models of the Deep-Time Model Intercomparison Project (DeepMIP), show general good agreement at low intertropical and high polar latitudes. However, widespread discrepancies between proxy reconstructed forests and woodlands and modelled dry shrublands and deserts, covering most of the subtropics and mid latitudes, reveal fundamental gaps in our understanding of the early Eocene hydrological cycle and/or vegetation-climate interaction.</div></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"261 ","pages":"Article 105036"},"PeriodicalIF":10.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heat flow and thermal structure of the South China Sea","authors":"Wenjing Zhu ,&nbsp;Shaowen Liu","doi":"10.1016/j.earscirev.2024.105028","DOIUrl":"10.1016/j.earscirev.2024.105028","url":null,"abstract":"<div><div>The South China Sea (SCS), the largest marginal sea in the western Pacific, is crucial for understanding geodynamic processes from continental breakup to seafloor spreading. The thermal state plays an important role in lithospheric deformation; however, that of the SCS remains poorly understood owing to poor data coverage and quality in early compilations. The incremental data accumulations over the decades enable an in-depth investigation of the thermal state of the SCS. A new compilation of 1338 heat flow data from the SCS indicates a high thermal condition with a mean of 75 mW/m². The central oceanic basin is uniformly hot while continental margins show strong lateral variations due to various tectonic settings and shallow environmental factors. Sedimentation correction considering both heat generation and thermal blanket was applied; the suppression on seafloor heat flow by sedimentation is as significant as 20 %–40 % in the Qiongdongnan Basin. A broad high heat flow anomaly zone is confirmed, extending from the ocean-continent transition in the northeast to the Xisha Trough and the central depression of the Qiongdongnan Basin. The combination of post-rifting magmatism and hydrothermal circulation is thought to be responsible for it. The thermal lithospheric thickness of the SCS is estimated to be 50–80 km and the mantle contributes more than 65 % of the seafloor heat flow. This compilation offers unprecedented insights into the heat flow pattern depiction and interpretation for the SCS.</div></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"261 ","pages":"Article 105028"},"PeriodicalIF":10.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143136841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Toward a big-data approach for reconstructing regional to global paleogeography and tectonic histories: Preface","authors":"Zheng-Xiang Li ,&nbsp;Bruce Eglington ,&nbsp;Tao Wang","doi":"10.1016/j.earscirev.2024.105030","DOIUrl":"10.1016/j.earscirev.2024.105030","url":null,"abstract":"<div><div>Geoscience has come to an era of addressing system-scale big science questions through synthesising the rapidly expanding bodies of discipline-based global databases, while sharply discipline-focused in-depth research is conducted to test hypotheses based on such syntheses. Such big-data oriented research has been further empowered by rapid developments in machine-learning-based artificial intelligence (AI) over recent years. This special issue presents some outcomes of IGCP 648 Supercontinent Cycles and Global Geodynamics (2015–2020) that feature work taking a big-data approach to address regional to global geotectonic issues. Papers in this volume have topics ranging from (1) the building of global palaeomagnetic and other geoscience databases, (2) development of statistical approaches and methods for using big-data analysis to address geoscience questions with quantified confidence estimation, (3) examples of applying big-data analysis to synthesise regional geotectonic and palaeographic reconstructions, (4) using big-data approaches to evaluate the chemical evolution of Earth's mantle and its lead isotope system, to (5) using multiple global datasets and geodynamic synthesis to reconstruct ancient Earth history that includes a full-plate reconstruction with palaeolongitude constraints back to 2 billion years, and related geodynamic evolution featuring a hypothesised first-order mantle structure evolution since 1.7 billion years ago.</div></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"261 ","pages":"Article 105030"},"PeriodicalIF":10.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143136875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ediacaran-Cambrian Boundary in the Anti-Atlas belt (Morocco): A review of biostratigraphy, chemostratigraphy and geochronology","authors":"Jamal El Kabouri ,&nbsp;Ezzoura Errami ,&nbsp;Fred T. Bowyer ,&nbsp;Bruno Beker-Kerber ,&nbsp;Said Belkacim","doi":"10.1016/j.earscirev.2024.105010","DOIUrl":"10.1016/j.earscirev.2024.105010","url":null,"abstract":"&lt;div&gt;&lt;div&gt;The Ediacaran-Cambrian transition represents a pivotal geological marker, denoting the decline of the Ediacaran biota and the emergence of most modern phyla in an interval marked by perturbations to the carbon cycle (as evidence by carbonate carbon isotopes, δ&lt;sup&gt;13&lt;/sup&gt;C&lt;sub&gt;carb&lt;/sub&gt;), biotic turnover, dynamic paleoredox regimes, and magnetic field instability. Following initial international expeditions to the Anti-Atlas belt in Morocco, numerous attempts have sought to pinpoint the exact stratigraphic level of the Ediacaran-Cambrian boundary (E-C) in this important succession, where ca. 3 km of continuous carbonate rocks provide one of the most complete successions for the establishment of a global δ&lt;sup&gt;13&lt;/sup&gt;C&lt;sub&gt;carb&lt;/sub&gt; chemostratigraphic reference curve. Subsequently, a growing number of publications have explored the stratigraphy, paleontology, and geochronology of the Ediacaran-Cambrian transition in the Anti-Atlas. Despite extensive efforts, the precise position of the E-C boundary in the Anti-Atlas remains ambiguous, with multiple proposed positions ranging from within the Ouarzazate Group to the lower part of the Tifnout Member (Adoudou Formation, Taroudant Group). Here, we conduct a comprehensive review of the available chemostratigraphic, paleontological, and geochronological data associated with the late Ediacaran-Cambrian Ouarzazate Group and Adoudou Formation within the Anti-Atlas belt. The objective is to refine our understanding of the regional expression of the E-C boundary and offer clarity on the inconsistencies observed among biostratigraphy, chemostratigraphy, and geochronology. This review underscores that the currently proposed boundary relies primarily on the δ&lt;sup&gt;13&lt;/sup&gt;C&lt;sub&gt;carb&lt;/sub&gt; excursion, lacking corroboration from other independent markers such as geochronology and globally significant ichnofossil assemblage constituents. Additionally, through the integration of newly available data and enhanced global chemostratigraphy, biostratigraphy, and geochronology, our findings suggest that the E-C boundary within the Western Anti-Atlas may be positioned as low as within the upper unit of the Tabia Member. However, this interpretation relies heavily on a Fortunian age for the ichnotaxa &lt;em&gt;Monomorphichnus&lt;/em&gt;, in the absence of co-occurring specimens of the boundary-defining ichnospecies &lt;em&gt;Treptichnus pedum&lt;/em&gt;. Moreover, a revised assessment of chemostratigraphic correlation and geochronological markers indicates that the Tabia and Tifnout members in the Central and Eastern Anti-Atlas do not correlate with the same named members in the Western Anti-Atlas. Both the Tabia and Tifnout members of the Central-Eastern Anti-Atlas may instead correlate with the middle part of Tifnout Member in the Western Anti-Atlas. This implies a late Ediacaran to early Cambrian ca. 10 m.y stratigraphic gap in the Central-Eastern Anti-Atlas and hence the E-C boundary in the Central-Eastern Anti-Atlas is likely sit","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"261 ","pages":"Article 105010"},"PeriodicalIF":10.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Paleoproterozoic (c. 2.3 Ga) Gowganda Formation: Deep water, glacially-influenced debrites and related mass flow along a passive margin","authors":"Kirsten Kennedy,&nbsp;Nicholas Eyles","doi":"10.1016/j.earscirev.2024.105033","DOIUrl":"10.1016/j.earscirev.2024.105033","url":null,"abstract":"<div><div>The Gowganda Formation (ca. 2.3 Ga) of the Huronian Supergroup in Northern Ontario, Canada is the best-preserved stratigraphic record of a Paleoproterozoic glaciogenic environment in the world. The Lower Gowganda has been ascribed to a putative panglacial ‘Snowball Earth’ event despite little agreement as to its origins, paleotectonic and paleogeographic setting, and paleolatitude. The present study leverages a large database of previous field investigations with new sedimentological, structural and basin analysis data that shows that Gowganda facies record glacially-influenced, subaqueous, gravity-driven mass flow processes in deep water. The Lower Gowganda Formation is dominated by hundred-meter thick amalgamated units of thickly-bedded to massive, chaotically-bedded and graded diamictites. It also contains thick (&gt;50 m) regionally extensive laminated mudstone units (‘laminites’) with a small number of mostly pebble-grade lonestones, and interbedded graded sandstone and conglomerates. We interpret diamictite facies as debrites formed by downslope subaqueous mixing of large volumes of unstable glacially-derived gravel, sand, and mud. Laminites are distal turbidites with sparse ice-rafted drop stones and outrunner clasts from adjacent debris flows. Interbedded massive and graded conglomerates and sandstones are identified as turbiditic deposits resulting from slumping and resedimentation of basin margin glaciofluvial or nearshore deposits; clast shapes and lithologies are the same as those in diamictites which is key evidence for remixing with mud during mass flow to generate thick regionally-extensive diamictites in a deep water base-of-slope setting. Ice contact, basin margin sediments were not preserved. There are clear sedimentological and paleotectonic parallels between the Gowganda Formation and glacially-influenced successions of younger Neopreoterozoic age indicating a commonality of depositional environments where glaciogenic sediment was recycled and focussed into evolving rifts during continental breakup and along succeeding passive margins. We emphasize the ongoing role of both basement faulting and glacial erosion in creating significant and evolving paleo-topographic relief, giving rise to marked variations in stratal thickness. We conclude that glaciogenic sediments were reworked by gravity and preserved along the tectonically-active passive margin of a recently-rifted Superior Craton during the breakup of Kenorland. Pleistocene glaciogenic sedimentation adjacent to modern uplifted passive basement margins, such as the coast of Norway, is an appropriate tectono-sedimentary analog.</div></div>","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"261 ","pages":"Article 105033"},"PeriodicalIF":10.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}