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Shuzhong Shen - One of the best experts on this subject based on the ideXlab platform.
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Mid-Permian (End-Guadalupian) Extinctions
Encyclopedia of Geology, 2021Co-Authors: Jun Chen, Shuzhong ShenAbstract:Abstract The end-Guadalupian mass extinction (i.e., pre-Lopingian crisis) has been recognized as a major biotic crisis in Earth's history for nearly three decades. As more and more evidence has been gathered in recent years, our understanding of this event has been enhanced and to some extent changed. Fossil evidence suggests that the end-Guadalupian mass extinction is not as severe as originally thought, and only happened at the community level and was taxonomically selective. The turnovers of major marine fossil groups occurred at different temporal levels, therefore the total duration is relatively extended, especially compared to the sudden end-Permian mass extinction. The nature of the turnover of terrestrial organisms around the Guadalupian-Lopingian boundary (GLB) is so far poorly known. Biostratigraphic constraints suggest that it most likely occurred in the latest Capitanian-earliest Wuchiapingian, a stratigraphic interval between the conodont Jinogondolella xuanhanensis and Clarkina dukouensis zones. Substantial environmental changes coincided with the end-Guadalupian mass extinction, including the largest sea-level fall, and major climate and ocean chemistry (e.g., δ13Ccarb, δ34S, and 87Sr/86Sr) changes. Considering evidence available within a unified temporal framework, the largest regression of the Paleozoic and Emeishan LIP (Large Igneous Province) volcanism are the most likely primary triggers, while other previously suggested causes such as long-term cooling, rapid fluctuations in seawater temperatures, ocean anoxia, explosive volcanism and cooling, and methane outburst with low atmospheric oxygen are either not supported by direct evidence, or were only secondary causes.
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first record of cisuralian Guadalupian plant fossils from the shan plateau eastern myanmar
Palaeoworld, 2020Co-Authors: Weiming Zhou, Shuzhong Shen, Yichun Zhang, Kyi Pyar Aung, Li Liu, Than Zaw, Jun WangAbstract:Abstract Permian plant fossils have never been reported from the Shan Plateau in eastern Myanmar. Recently, a black to gray carbonaceous mudstone unit containing abundant plant fossils was discovered just below the lowest part of Thitspin Limestone Formation from the Linwe Area, eastern Myanmar. Although only five taxa were identified, the plant assemblage provides the first evidence of the occurrence of Cathaysian elements in eastern Myanmar and potentially indicates the presence of a highly diverse Permian flora. Among the five species, Cordaites principalis and Annularia mucronata were cosmopolitan species; while Callipteridum cf. koraiense, Taeniopteris crassinervis Mo and Rhipidopsis lobata were mostly recorded in the Cathaysia Flora. Therefore, the present assemblage generally indicates a palaeobiogeographical affinity to the Cathaysian Province. Stratigraphically, Callipteridum cf. koraiense was mainly reported from Cisuralian to Wordian; whereas Taeniopteris crasssnervis Mo and Rhipidopsis lobata were recorded from Capitanian to Changhsingian, which suggests a general Permian age based on the plant assemblage itself only. However, the carbonaceous mudstone at the outcrop is overlain by the Thitspin Limestone Formation containing middle Guadalupian fusulinids. Based on previous faunal analyses, the Sibumasu terrane contains typical Gondwanan cold-water faunas during the early Cisuralian, warm-water faunas occurred after Sakmarian. Thus, age of the fossil-plant-containing carbonaceous mudstone is very likely between late Cisuralian and early Guadalupian as constrained by its overlying fusulinids and its warm Cathaysian palaeobiogeographical affinity.
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Progress, problems and prospects: An overview of the Guadalupian Series of South China and North America
Earth-Science Reviews, 2020Co-Authors: Shuzhong Shen, Charles M Henderson, Dongxun Yuan, Yichun Zhang, Hua Zhang, Jahandar Ramezani, Xiangdong Wang, Lance L. LambertAbstract:Abstract The Guadalupian Epoch is marked by the formation of the Pangean supercontinent, global sea-level change, rifting and drifting of the Cimmerian continents, formation of large igneous provinces and dramatic biotic changes. A high-resolution biostratigraphic, chemostratigraphic and high-precision geochronologic framework of this critical transition is fundamental to understanding these events. Extensive studies of the latest Cisuralian and Guadalupian Series in both South China and North America reveal the same conodont lineages, but the conodont interval zones based on Jinogondolella within the Guadalupian Series are slightly diachronous. High-precision U-Pb geochronological studies (CA-ID-TIMS method) calibrate the base of the Guadalupian Series (base Roadian) at 273.01 ± 0.14 Ma. A previously reported age from an ash bed overlying the Emeishan flood basalts, 259.51 ± 0.21 Ma, is adopted for the Guadalupian/Lopingian boundary (GLB). Based on recently published geochronology and Bayesian age modeling from the Guadalupian Series, the base of the Capitanian is constrained at 264.28 ± 0.16 Ma and the base of the Wordian is interpolated to be 266.9 ± 0.4 Ma. The Illawarra Reversal is of early-middle Wordian age. Both North America and South China possess a distinct negative δ13Ccarb excursion of 3-5‰ at the latest Kungurian and early Roadian (LK-ER CIE), which coincides with the early stages of a significant 3rd order sea-level rise. The large end-Guadalupian δ13Ccarb negative excursion may have been affected by post-depositional diagenesis or a warming event associated with the Emeishan volcanism. The 87Sr/86Sr ratios in both regions declined from the latest Kungurian to the late Capitanian, but have different ratios and reveal several fluctuations in the middle Guadalupian. Measured δ18Oapatite values suggest that the Delaware Basin was 3-4°C cooler than the eastern Yangtze Block. Analysis of a new high-resolution database of marine taxa indicates only a minor pre-Lopingian diversity drop from 261.04 Ma to 259.98 Ma, which coincides with the peak Emeishan volcanism. The widely-perceived “end-Guadalupian mass extinction” in North America is evidently masked by, and possibly an artefact of, a stratigraphic truncation effect due to rapid lithofacies changes from limestone to laminated evaporites with the closure of the west Texas basins.
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High-precision U-Pb zircon age constraints on the Guadalupian in West Texas, USA
Palaeogeography Palaeoclimatology Palaeoecology, 2020Co-Authors: Jahandar Ramezani, Charles M Henderson, Dongxun Yuan, Yichun Zhang, Hua Zhang, Lance L. Lambert, Douglas H. Erwin, Shuzhong ShenAbstract:Abstract The Guadalupian Epoch was characterized by major changes in paleogeography, paleoclimate, and biodiversity. Yet, the paucity of precise and accurate radioisotopic dates from the Guadalupian stages in their type area, Guadalupe Mountains National Park in West Texas has rendered their calibration inadequate. In this study, we report high-precision U-Pb zircon geochronology by the CA-ID-TIMS method from three ash beds (2σ internal errors only) in the Rader Member of the Bell Canyon Formation at the Back Ridge Section (262.127 ± 0.097 Ma, MSWD = 0.89, n = 3), the lower Pinery Member of the Bell Canyon Formation at the Frijole Section (264.23 ± 0.13 Ma, MSWD = 0.89, n = 8) and the basal South Wells Member of the Cherry Canyon Formation at the Monolith Canyon Section (266.525 ± 0.078 Ma, MSWD = 0.62, n = 5). The Bayesian interpolation statistics method is used to establish an age-stratigraphy model that estimates the base of the Capitanian to be 264.28 ± 0.16 Ma, serving as the best age estimate for the Capitanian Stage at present. In addition, we review the existing geochronology from the Guadalupian Series in West Texas and seek to propose more precise temporal estimates of Guadalupian geological and biological events. These data constrain the high-frequency sequences of the Cherry Canyon and Bell Canyon formations in the Guadalupe Mountains National Park area. Accordingly, the base of the Wordian is estimated at 266.9 ± 0.4 Ma and the Illawarra geomagnetic polarity reversal in West Texas at 267.4 ± 0.4 Ma to 266.5 ± 0.3 Ma. The global end-Guadalupian extinction began in the conodont zone of Jinogondolella altudaensis above the base of the Reef Trail Member of the Bell Canyon Formation and might continue to the Clarkina postbitteri postbitteri Zone in the earliest Wuchiapingian. The conodonts display a rapid evolutionary rate during this interval. This constrains the biotic crisis from ca. 260 Ma to 259 Ma based on our conodont age estimation. The emplacement of the Emeishan Large Igneous Province (ELIP) in South China has been constrained to ca. 260 Ma to 257.4 Ma based on zircon U-Pb geochronology by the CA-ID-TIMS method, overlapping with the end-Guadalupian extinction, which provides support for the temporal relationship between them. Additionally, the ELIP persisted into the early Wuchiapingian and may have hampered ecosystem restoration during the post-extinction interval.
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First record of Cisuralian–Guadalupian plant fossils from the Shan Plateau, eastern Myanmar
Palaeoworld, 2020Co-Authors: Weiming Zhou, Yichun Zhang, Kyi Pyar Aung, Li Liu, Than Zaw, Jun Wang, Shuzhong ShenAbstract:Abstract Permian plant fossils have never been reported from the Shan Plateau in eastern Myanmar. Recently, a black to gray carbonaceous mudstone unit containing abundant plant fossils was discovered just below the lowest part of Thitspin Limestone Formation from the Linwe Area, eastern Myanmar. Although only five taxa were identified, the plant assemblage provides the first evidence of the occurrence of Cathaysian elements in eastern Myanmar and potentially indicates the presence of a highly diverse Permian flora. Among the five species, Cordaites principalis and Annularia mucronata were cosmopolitan species; while Callipteridum cf. koraiense, Taeniopteris crassinervis Mo and Rhipidopsis lobata were mostly recorded in the Cathaysia Flora. Therefore, the present assemblage generally indicates a palaeobiogeographical affinity to the Cathaysian Province. Stratigraphically, Callipteridum cf. koraiense was mainly reported from Cisuralian to Wordian; whereas Taeniopteris crasssnervis Mo and Rhipidopsis lobata were recorded from Capitanian to Changhsingian, which suggests a general Permian age based on the plant assemblage itself only. However, the carbonaceous mudstone at the outcrop is overlain by the Thitspin Limestone Formation containing middle Guadalupian fusulinids. Based on previous faunal analyses, the Sibumasu terrane contains typical Gondwanan cold-water faunas during the early Cisuralian, warm-water faunas occurred after Sakmarian. Thus, age of the fossil-plant-containing carbonaceous mudstone is very likely between late Cisuralian and early Guadalupian as constrained by its overlying fusulinids and its warm Cathaysian palaeobiogeographical affinity.
Yukio Isozaki - One of the best experts on this subject based on the ideXlab platform.
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Multiple sulfur isotope records at the end-Guadalupian (Permian) at Chaotian, China: Implications for a role of bioturbation in the Phanerozoic sulfur cycle
Journal of Asian Earth Sciences, 2017Co-Authors: Masafumi Saitoh, Yukio Isozaki, Jianxin Yao, Yuichiro Ueno, Tetsuya Kawamura, Fumihiro Matsuura, Naohiro YoshidaAbstract:Abstract A recent study on quadruple sulfur isotopes (32S, 33S, 34S, and 36S) of sedimentary pyrite suggested that the end-Guadalupian extinction was caused by shoaling of the sulfidic deep-water. This scenario is based on the assumption that sulfur isotopic compositions of pyrite from hosting sediments were controlled by benthos activities, thus by the redox conditions of the sedimentary environments. Nonetheless, the relationship between the sulfur isotope records and redox conditions, reconstructed from litho- and bio-facies, are poorly known. In order to examine the effect of bioturbation in sediments, quadruple sulfur isotopic compositions of sedimentary pyrite from the end-Guadalupian succession in Chaotian, South China, were analyzed. Black mudstones of deep-water facies immediately below the extinction horizon have consistently high Δ33S values of ca. +0.079‰, clearly suggesting a sulfate reduction in the anoxic water column. Our new data are consistent with the emergence of a sulfidic deep-water mass prior to the end-Guadalupian extinction; the upwelling of the toxic deep-water may have contributed to the extinction. In contrast, shallow-marine bioclastic limestones with burrows deposited under oxic conditions have negative Δ33S values. This anomalous isotopic signal indicates the mixing of two distinct types of pyrite; one generated during the sulfate reduction in an open system and the other in a closed system. We interpret that bioturbation supplied sulfate in the sediments and promoted sulfate reduction and in-situ sulfide precipitation within the sediments. The negative Δ33S values of oxic sediments in Chaotian are inconsistent with the previous model and demonstrate that the sedimentary sulfur cycle associated with bioturbation was more complicated than previously thought. Our study also implies that, more generally, the role of bioturbation in increasing seawater sulfate concentration in the Phanerozoic may have been overestimated in the previous studies, because bioturbation may have enhanced sulfide burial or sulfur output from the oceans.
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Isotopic evidence for water-column denitrification and sulfate reduction at the end-Guadalupian (Middle Permian)
Global and Planetary Change, 2014Co-Authors: Masafumi Saitoh, Yukio Isozaki, Jianxin Yao, Yuichiro Ueno, Manabu Nishizawa, Katsumi Shozugawa, Tetsuya Kawamura, Ken Takai, Naohiro YoshidaAbstract:The total nitrogen and pyrite sulfur isotopic compositions of the Guadalupian–Lopingian (Middle-Upper Permian) shelf carbonates are analyzed at Chaotian in northern Sichuan, South China, to clarify the environmental changes in the relatively deep disphotic zone (generally deeper than 150 m) in the ocean at the end-Guadalupian, focusing on the possible relationships with the deep-sea oxygen depletion and the shallow-sea extinction. At Chaotian, the Guadalupian Maokou Formation and the Early Lopingian Wujiaping Formation are primarily composed of bioclastic limestone of shallow-water facies, although the topmost part of the Maokou Formation (ca. 11 m thick) is composed of bedded black mudstone and chert that was deposited on the disphotic slope/basin under anoxic conditions. Substantially high δ15N values of total nitrogen (up to + 14‰) in the topmost Maokou Formation of the deep-water facies indicate water-mass denitrification. In the same disphotic interval, the consistently low δ34S values of pyrite (ca. − 37‰) suggest sulfate reduction in the sulfate-rich water column. The new nitrogen and sulfur isotopic records at Chaotian indicate the enhanced anaerobic respiration in the oxygen-depleted disphotic zone in the Late Guadalupian in northwestern South China. The active water-column sulfate reduction likely resulted in the emergence of a sulfidic deep-water mass on the disphotic slope/basin, which is supported by the high proportions of pyrite Fe to highly reactive Fe in the rocks shown using 57Fe Mossbauer spectroscopy. The anaerobic respiration in the disphotic zone at the end-Guadalupian may have been enhanced by an expansion of the oxygen minimum zone (OMZ) caused by the increased primary productivity in the surface oceans; the OMZ expansion may have corresponded to the onset of prolonged oxygen depletion in the deep sea. The clear stratigraphic relationship at Chaotian shows the emergence of the sulfidic deep-waters preceding the extinction, implying that the upwelling of the sulfidic deep-water from the previously overlooked disphotic zone to the shallow shelves along the continental margin may have acted as a stress to the shallow-marine biota.
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The Guadalupian (Permian) Kamura event in European Tethys
Palaeogeography Palaeoclimatology Palaeoecology, 2010Co-Authors: Yukio Isozaki, Dunja Aljinović, Hodaka KawahataAbstract:article i nfo In order to document paleoenvironmental conditions of the equatorial western Paleo-Tethys during the late Middle Permian prior to the end-Guadalupian mass extinction, chemostratigraphic analysis using stable carbon isotopes was conducted for the Guadalupian rocks at Brusane in the Velebit Mtn., central Croatia. By analyzing 72 carbonate samples of the Capitanian (Upper Guadalupian) Velebit Formation, we found an interval with unusually high δ 13 Ccarb values (+4 to +6‰) in the ca. 150 m-thick Yabeina (fusuline) Zone. The present find clarifies that the primary productivity and burial rate into the sediments were considerably high during the Capitanian in westernmost Paleo-Tethys. This chemostratigraphic signal is properly correlated with the "Kamura event" detected in a mid-Panthalassan paleo-atoll limestone in Japan. The present results identify the Capitanian "Kamura event" for the first time in European Paleo-Tethys on the opposite side of the globe from the mid-Panthalassan paleo-seamount, and prove the global context of the event as well as its utility in chemostratigraphic correlation. In order to enhance bioproductivity on a global scale, the increase in nutrient supply is inevitable. In addition to riverine run-off from Pangea, active oceanic circulation, in particular upwelling of deep-sea water enriched in nutrients, was likely vital both in Panthalassa and Paleo- Tethys. The extinction of some Guadalupian fauna, in particular photosymbiotic community (large-tested fusulines, large bivalves, rugose corals), was likely related to a temporary cooling coupled with eutrophication in low-latitude shallow marine environments of Paleo-Tethys and Panthalassa.
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An Early-Middle Guadalupian (Permian) isotopic record from a mid-oceanic carbonate buildup: Akiyoshi Limestone, Japan
Global and Planetary Change, 2010Co-Authors: Masaaki Musashi, Yukio Isozaki, Hodaka KawahataAbstract:Abstract In order to understand the oceanographic changes before the Guadalupian–Lopingian (Permian) boundary mass extinction event, we investigated the isotopic compositions of the inorganic carbon and the oxygen ( δ 13 C carb and δ 18 O carb ) of the Guadalupian (Middle Permian) shallow marine carbonates deposited on a seamount-top in the superocean Panthalassa. The drilled samples were obtained at Kaerimizu in the Akiyoshi area, SW Japan. We focused on the Roadian-Wordian (Middle Guadalupian) interval that spans over 7 fusuline zones; i.e. the Parafusulina kaerimizuensis Zone ( Pk Z.), Afghanella ozawai Zone ( Ao Z.), Neoschwagerina craticulifera robusta Zone ( Ncr Z.), Verbeekina verbeeki – Afghanella schenki Zone ( Vv – As Z.), Neoschwageina fusifor m is Zone ( Nf Z.), Verbeekina verbeeki Zone ( Vv Z.), and Colania douvillei Zone ( Cd Z.), in ascending order. Analytical results showed that the δ 13 C carb values stayed almost constant around + 3.0‰ PDB in the Pk Z., Ao Z. and the lower half of the Ncr Z., and those in the upper-section gradually decreased down to −2.0‰, of which the lowest was found in the Cd Z. We statistically extracted the samples with presumably better preserved δ 13 C carb values in the Kaerimizu section ranged between + 0.5 and + 4.0‰ with average values of δ 13 C carb of + 2.7 ± 1.0‰, on the basis of δ 13 C carb – δ 18 O carb characterization. This interval shows a monotonous decrease in δ 13 C carb values from ca + 4.0‰ to + 2.0‰. This indicates that the primary productivity might be generally high in the Wordian mid-oceanic domain but slightly declined in the Late Wordian. The studied Early-Middle Guadalupian interval is chemostratigraphically correlated with the other mid-Pansalassan paleo-atoll limestone e.g. Iwato Formation in Japan, suggesting that the relatively high δ 13 C carb (over + 3.0‰) of seawater predominated in shallow mid-superocean during the middle Middle Permian.
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End of gigantism in tropical seas by cooling: End-Guadalupian (Permian) extinction of the photosymbiotic tropical trio
2010Co-Authors: Yukio Isozaki, Dunja AljinovićAbstract:The unique Permian bivalve family Alatoconchidae has aberrant shell forms and extraordinary size up to 1 m, representing the largest bivalve group in the Paleozoic, Their occurrence is reported sporadically from Lower-Middle Perman shallow marine carbonates in 9 areas in the world (Tunisia, Craotia, Oman, Iran, Afghanistan, Thailand, Malaysia, The Philippines and Japan) that cover low-latitudes of both the Tethyan and Panthalassan domains. Alatoconchids almost always occurred in a close association with large-tested fusulines (Verbeekinidae) and/or rugose corals Waagenophyllidae of the typical Tethyan assemblage, suggesting their preferential adaption to shallow warm-water (tropical) environments. This "tropical trio" (Alatoconchidae, Verbeekinidae and Waagenophyllidae) became extinct either during the late Guadalupian or around the Guadalupian-Lopingian boundary (G-LB). Their intimate association and occurrence range suggests that these 3 taxonomically distinct clades may have shared not only a common habit but also a common cause of extinction. The shell structure of alatoconchids suggests their symbiosis with photosynthetic organisms (algae + cyanobacteria) in order to maintain their large body size that required high energy-consuming metabolism in contrast to smaller forms. The Alatoconchidae attained their largest size in the Wordian (Middle Guadalupian), probably maximizing the benefits of photosymbiosis. The subsequent extinction of the warm-water-adapted "tropical trio" both in Tethys and Panthalassa positively supports the concept that a critical cooling took place on a global scale, including low-latitude oceans. The end of gigantism in fusulines and bivalves in the Capitanian (Late Guadalupian) was likely caused by the collapse of photosymbiotic systems during a temporary temperature drop of seawater (Kamura cooling event) coupled with eutrophication that was detrimental to the tropical fauna adapted particularly to oligotrophic condition. Gigantism of bivalves occurred several times in the Phanerozoic ; e.g., Siluro-Devonian, Permian, Triassic-Jurassic and Jurassic-Craataceous, mostly in warm periods. The sea-level change in the Phanerozoic apparently synchronized with the intermittent rise and decline of bivalve gigantism, suggesting that the gigantism in low-latitudes may serve as a potential monitor of global warming/cooling in the past.
Yichun Zhang - One of the best experts on this subject based on the ideXlab platform.
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first record of cisuralian Guadalupian plant fossils from the shan plateau eastern myanmar
Palaeoworld, 2020Co-Authors: Weiming Zhou, Shuzhong Shen, Yichun Zhang, Kyi Pyar Aung, Li Liu, Than Zaw, Jun WangAbstract:Abstract Permian plant fossils have never been reported from the Shan Plateau in eastern Myanmar. Recently, a black to gray carbonaceous mudstone unit containing abundant plant fossils was discovered just below the lowest part of Thitspin Limestone Formation from the Linwe Area, eastern Myanmar. Although only five taxa were identified, the plant assemblage provides the first evidence of the occurrence of Cathaysian elements in eastern Myanmar and potentially indicates the presence of a highly diverse Permian flora. Among the five species, Cordaites principalis and Annularia mucronata were cosmopolitan species; while Callipteridum cf. koraiense, Taeniopteris crassinervis Mo and Rhipidopsis lobata were mostly recorded in the Cathaysia Flora. Therefore, the present assemblage generally indicates a palaeobiogeographical affinity to the Cathaysian Province. Stratigraphically, Callipteridum cf. koraiense was mainly reported from Cisuralian to Wordian; whereas Taeniopteris crasssnervis Mo and Rhipidopsis lobata were recorded from Capitanian to Changhsingian, which suggests a general Permian age based on the plant assemblage itself only. However, the carbonaceous mudstone at the outcrop is overlain by the Thitspin Limestone Formation containing middle Guadalupian fusulinids. Based on previous faunal analyses, the Sibumasu terrane contains typical Gondwanan cold-water faunas during the early Cisuralian, warm-water faunas occurred after Sakmarian. Thus, age of the fossil-plant-containing carbonaceous mudstone is very likely between late Cisuralian and early Guadalupian as constrained by its overlying fusulinids and its warm Cathaysian palaeobiogeographical affinity.
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Progress, problems and prospects: An overview of the Guadalupian Series of South China and North America
Earth-Science Reviews, 2020Co-Authors: Shuzhong Shen, Charles M Henderson, Dongxun Yuan, Yichun Zhang, Hua Zhang, Jahandar Ramezani, Xiangdong Wang, Lance L. LambertAbstract:Abstract The Guadalupian Epoch is marked by the formation of the Pangean supercontinent, global sea-level change, rifting and drifting of the Cimmerian continents, formation of large igneous provinces and dramatic biotic changes. A high-resolution biostratigraphic, chemostratigraphic and high-precision geochronologic framework of this critical transition is fundamental to understanding these events. Extensive studies of the latest Cisuralian and Guadalupian Series in both South China and North America reveal the same conodont lineages, but the conodont interval zones based on Jinogondolella within the Guadalupian Series are slightly diachronous. High-precision U-Pb geochronological studies (CA-ID-TIMS method) calibrate the base of the Guadalupian Series (base Roadian) at 273.01 ± 0.14 Ma. A previously reported age from an ash bed overlying the Emeishan flood basalts, 259.51 ± 0.21 Ma, is adopted for the Guadalupian/Lopingian boundary (GLB). Based on recently published geochronology and Bayesian age modeling from the Guadalupian Series, the base of the Capitanian is constrained at 264.28 ± 0.16 Ma and the base of the Wordian is interpolated to be 266.9 ± 0.4 Ma. The Illawarra Reversal is of early-middle Wordian age. Both North America and South China possess a distinct negative δ13Ccarb excursion of 3-5‰ at the latest Kungurian and early Roadian (LK-ER CIE), which coincides with the early stages of a significant 3rd order sea-level rise. The large end-Guadalupian δ13Ccarb negative excursion may have been affected by post-depositional diagenesis or a warming event associated with the Emeishan volcanism. The 87Sr/86Sr ratios in both regions declined from the latest Kungurian to the late Capitanian, but have different ratios and reveal several fluctuations in the middle Guadalupian. Measured δ18Oapatite values suggest that the Delaware Basin was 3-4°C cooler than the eastern Yangtze Block. Analysis of a new high-resolution database of marine taxa indicates only a minor pre-Lopingian diversity drop from 261.04 Ma to 259.98 Ma, which coincides with the peak Emeishan volcanism. The widely-perceived “end-Guadalupian mass extinction” in North America is evidently masked by, and possibly an artefact of, a stratigraphic truncation effect due to rapid lithofacies changes from limestone to laminated evaporites with the closure of the west Texas basins.
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High-precision U-Pb zircon age constraints on the Guadalupian in West Texas, USA
Palaeogeography Palaeoclimatology Palaeoecology, 2020Co-Authors: Jahandar Ramezani, Charles M Henderson, Dongxun Yuan, Yichun Zhang, Hua Zhang, Lance L. Lambert, Douglas H. Erwin, Shuzhong ShenAbstract:Abstract The Guadalupian Epoch was characterized by major changes in paleogeography, paleoclimate, and biodiversity. Yet, the paucity of precise and accurate radioisotopic dates from the Guadalupian stages in their type area, Guadalupe Mountains National Park in West Texas has rendered their calibration inadequate. In this study, we report high-precision U-Pb zircon geochronology by the CA-ID-TIMS method from three ash beds (2σ internal errors only) in the Rader Member of the Bell Canyon Formation at the Back Ridge Section (262.127 ± 0.097 Ma, MSWD = 0.89, n = 3), the lower Pinery Member of the Bell Canyon Formation at the Frijole Section (264.23 ± 0.13 Ma, MSWD = 0.89, n = 8) and the basal South Wells Member of the Cherry Canyon Formation at the Monolith Canyon Section (266.525 ± 0.078 Ma, MSWD = 0.62, n = 5). The Bayesian interpolation statistics method is used to establish an age-stratigraphy model that estimates the base of the Capitanian to be 264.28 ± 0.16 Ma, serving as the best age estimate for the Capitanian Stage at present. In addition, we review the existing geochronology from the Guadalupian Series in West Texas and seek to propose more precise temporal estimates of Guadalupian geological and biological events. These data constrain the high-frequency sequences of the Cherry Canyon and Bell Canyon formations in the Guadalupe Mountains National Park area. Accordingly, the base of the Wordian is estimated at 266.9 ± 0.4 Ma and the Illawarra geomagnetic polarity reversal in West Texas at 267.4 ± 0.4 Ma to 266.5 ± 0.3 Ma. The global end-Guadalupian extinction began in the conodont zone of Jinogondolella altudaensis above the base of the Reef Trail Member of the Bell Canyon Formation and might continue to the Clarkina postbitteri postbitteri Zone in the earliest Wuchiapingian. The conodonts display a rapid evolutionary rate during this interval. This constrains the biotic crisis from ca. 260 Ma to 259 Ma based on our conodont age estimation. The emplacement of the Emeishan Large Igneous Province (ELIP) in South China has been constrained to ca. 260 Ma to 257.4 Ma based on zircon U-Pb geochronology by the CA-ID-TIMS method, overlapping with the end-Guadalupian extinction, which provides support for the temporal relationship between them. Additionally, the ELIP persisted into the early Wuchiapingian and may have hampered ecosystem restoration during the post-extinction interval.
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First record of Cisuralian–Guadalupian plant fossils from the Shan Plateau, eastern Myanmar
Palaeoworld, 2020Co-Authors: Weiming Zhou, Yichun Zhang, Kyi Pyar Aung, Li Liu, Than Zaw, Jun Wang, Shuzhong ShenAbstract:Abstract Permian plant fossils have never been reported from the Shan Plateau in eastern Myanmar. Recently, a black to gray carbonaceous mudstone unit containing abundant plant fossils was discovered just below the lowest part of Thitspin Limestone Formation from the Linwe Area, eastern Myanmar. Although only five taxa were identified, the plant assemblage provides the first evidence of the occurrence of Cathaysian elements in eastern Myanmar and potentially indicates the presence of a highly diverse Permian flora. Among the five species, Cordaites principalis and Annularia mucronata were cosmopolitan species; while Callipteridum cf. koraiense, Taeniopteris crassinervis Mo and Rhipidopsis lobata were mostly recorded in the Cathaysia Flora. Therefore, the present assemblage generally indicates a palaeobiogeographical affinity to the Cathaysian Province. Stratigraphically, Callipteridum cf. koraiense was mainly reported from Cisuralian to Wordian; whereas Taeniopteris crasssnervis Mo and Rhipidopsis lobata were recorded from Capitanian to Changhsingian, which suggests a general Permian age based on the plant assemblage itself only. However, the carbonaceous mudstone at the outcrop is overlain by the Thitspin Limestone Formation containing middle Guadalupian fusulinids. Based on previous faunal analyses, the Sibumasu terrane contains typical Gondwanan cold-water faunas during the early Cisuralian, warm-water faunas occurred after Sakmarian. Thus, age of the fossil-plant-containing carbonaceous mudstone is very likely between late Cisuralian and early Guadalupian as constrained by its overlying fusulinids and its warm Cathaysian palaeobiogeographical affinity.
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a new changhsingian brachiopod fauna from the xiala formation at tsochen in the central lhasa block and its paleogeographical implications
Journal of Paleontology, 2019Co-Authors: Yichun Zhang, Feng Qiao, Shuzhong ShenAbstract:Permian faunal affinity in the Lhasa Block plays a critical role in reconstructing its paleogeographic evolution. Cisuralian and Guadalupian faunas have been described from the Lhasa Block, but very few Lopingian (late Permian) brachiopods have been reported so far. In this paper, a new diverse brachiopod fauna consisting of 17 species of 17 genera and an unidentifiable Orthotetoidea is described from the uppermost part of the Xiala Formation at the Aduogabu section in the central part of the Lhasa Block. The age of this fauna can be assigned to the Changhsingian (late Lopingian) as indicated by the associated foraminifers Colaniella parva (Colani, 1924) and Reichelina pulchra Miklukho-Maklay, 1954. Characteristic brachiopods include Spinomarginifera chengyaoyenensis Huang, 1932, Haydenella wenganensis (Huang, 1932), and Araxathyris cf. dilatatus Shen, He, and Zhu, 1992. They also generally suggest a Changhsingian age. Paleobiogeographically, this fauna is uniformly composed of typical Tethyan elements represented by Spinomarginifera Huang, 1932 and Haydenella Reed, 1944, and some cosmopolitan elements, but no typical cold-water taxa of Gondwanan affinity. This is in contrast to the contemporaneous brachiopod faunas from the Tethys Himalayan region that are characterized by typical cold-water taxa of Gondwanan affinity, e.g., Costiferina indica (Waagen, 1884), Retimarginifera xizangensis Shen et al., 2000, Neospirifer (Quadrospina) tibetensis Ding, 1962. Thus, it is strongly indicative that the Lhasa Block had drifted into a relatively warm-water regime during the Changhsingian. An analysis of the paleobiogeographic change of brachiopods in the Lhasa Block throughout the entire Permian further suggests that the Lhasa Block probably had rifted away from the northern peri-Gondwanan margin between the latest Cisuralian and middle Guadalupian, that is, the Neotethys Ocean had opened before middle Guadalupian.
Ayano Ota - One of the best experts on this subject based on the ideXlab platform.
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a unique carbon isotope record across the Guadalupian lopingian middle upper permian boundary in mid oceanic paleo atoll carbonates the high productivity kamura event and its collapse in panthalassa
Global and Planetary Change, 2007Co-Authors: Yukio Isozaki, Hodaka Kawahata, Ayano OtaAbstract:Abstract Middle to Upper Permian shallow marine carbonates in the Kamura area, Kyushu (SW Japan), were derived from a paleo-atoll complex developed on an ancient seamount in mid-Panthalassa. The Capitanian (Upper Guadalupian) Iwato Formation (19 m-thick dark gray limestone) and the conformably overlying Wuchiapingian (Lower Lopingian) Mitai Formation (17 m-thick light gray dolomitic limestone) are composed of bioclastic limestone of subtidal facies, yielding abundant fusulines. A secular change in stable carbon isotope ratio of carbonate carbon (δ13Ccarb) was analyzed in the Kamura section in order to document the oceanographic change in the superocean Panthalassa with respect to the mass extinction across the Guadalupian–Lopingian boundary (G–LB). The Iwato Formation is characterized mostly by unusually high positive δ13Ccarb values of + 4.9 to + 6.2‰, whereas the Mitai Formation by low positive values from + 1.9 to + 3.5‰. The negative excursion occurred in three steps around the G–LB and the total amount of the negative shifts reached over 4‰. A remarkably sharp drop in δ13Ccarb values, for 2.4‰ from 5.3 down to 2.9‰, occurs in a 2 m-thick interval of the topmost Iwato Formation, after all large-shelled fusulines and bivalves disappeared abruptly. Such a prominent high positive δ13Ccarb plateau interval in the end-Guadalupian followed by a large negative shift across the G–LB was detected for the first time, and this trend in the mid-superoceanic sequence is correlated chemostratigraphically in part with the GSSP (Global Stratotype Section and Point) candidate for the G–LB in S. China. The present results prove that the end-Guadalupian event was doubtlessly global in context, affecting circum-Pangean basins, Tethys, and Panthalassa. The end-Guadalupian interval of a high positive plateau in δ13Ccarb values over + 5‰ is particularly noteworthy because it recorded an unusually high bio-productivity period that has not been known in the Permian. This end-Guadalupian high-productivity event, newly named “Kamura event”, suggests burial of a huge amount of organic carbon, draw-down of atmospheric CO2 and resultant global cooling at the end of Guadalupian, considerably after the Gondwana glaciation. The low temperatures during the Kamura event may have caused the end-Guadalupian extinction of large-shelled Tethyan fusulines and bivalves adapted to warm climate. On the other hand, the following event of ca. 4‰ negative shift in δ13Ccarb values across the G–LB indicates a global warming in the early Lopingian. This may have allowed radiation of the new Wuchiapingian fauna, and this trend appears to have continued into the Mesozoic. These observations are in good agreement with the global sea-level curve in the Middle–Late Permian. The smooth and gradual pattern of the negative shift suggests that the causal mechanism was not of catastrophic nature (e.g. bolide impact, sudden melting of methane hydrate) but was long and continuous.
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A unique carbon isotope record across the Guadalupian¿Lopingian (Middle¿Upper Permian) boundary in mid-oceanic paleo-atoll carbonates: The high-productivity ¿Kamura event¿ and its collapse in Panthalassa
Global and Planetary Change, 2006Co-Authors: Yukio Isozaki, Hodaka Kawahata, Ayano OtaAbstract:Abstract Middle to Upper Permian shallow marine carbonates in the Kamura area, Kyushu (SW Japan), were derived from a paleo-atoll complex developed on an ancient seamount in mid-Panthalassa. The Capitanian (Upper Guadalupian) Iwato Formation (19 m-thick dark gray limestone) and the conformably overlying Wuchiapingian (Lower Lopingian) Mitai Formation (17 m-thick light gray dolomitic limestone) are composed of bioclastic limestone of subtidal facies, yielding abundant fusulines. A secular change in stable carbon isotope ratio of carbonate carbon (δ13Ccarb) was analyzed in the Kamura section in order to document the oceanographic change in the superocean Panthalassa with respect to the mass extinction across the Guadalupian–Lopingian boundary (G–LB). The Iwato Formation is characterized mostly by unusually high positive δ13Ccarb values of + 4.9 to + 6.2‰, whereas the Mitai Formation by low positive values from + 1.9 to + 3.5‰. The negative excursion occurred in three steps around the G–LB and the total amount of the negative shifts reached over 4‰. A remarkably sharp drop in δ13Ccarb values, for 2.4‰ from 5.3 down to 2.9‰, occurs in a 2 m-thick interval of the topmost Iwato Formation, after all large-shelled fusulines and bivalves disappeared abruptly. Such a prominent high positive δ13Ccarb plateau interval in the end-Guadalupian followed by a large negative shift across the G–LB was detected for the first time, and this trend in the mid-superoceanic sequence is correlated chemostratigraphically in part with the GSSP (Global Stratotype Section and Point) candidate for the G–LB in S. China. The present results prove that the end-Guadalupian event was doubtlessly global in context, affecting circum-Pangean basins, Tethys, and Panthalassa. The end-Guadalupian interval of a high positive plateau in δ13Ccarb values over + 5‰ is particularly noteworthy because it recorded an unusually high bio-productivity period that has not been known in the Permian. This end-Guadalupian high-productivity event, newly named “Kamura event”, suggests burial of a huge amount of organic carbon, draw-down of atmospheric CO2 and resultant global cooling at the end of Guadalupian, considerably after the Gondwana glaciation. The low temperatures during the Kamura event may have caused the end-Guadalupian extinction of large-shelled Tethyan fusulines and bivalves adapted to warm climate. On the other hand, the following event of ca. 4‰ negative shift in δ13Ccarb values across the G–LB indicates a global warming in the early Lopingian. This may have allowed radiation of the new Wuchiapingian fauna, and this trend appears to have continued into the Mesozoic. These observations are in good agreement with the global sea-level curve in the Middle–Late Permian. The smooth and gradual pattern of the negative shift suggests that the causal mechanism was not of catastrophic nature (e.g. bolide impact, sudden melting of methane hydrate) but was long and continuous.
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fusuline biotic turnover across the Guadalupian lopingian middle upper permian boundary in mid oceanic carbonate buildups biostratigraphy of accreted limestone in japan
Journal of Asian Earth Sciences, 2006Co-Authors: Ayano Ota, Yukio IsozakiAbstract:Abstract Two sections in Upper Middle to Lower Upper Permian shallow-water limestones at Kamura and Akasaka in southwest Japan were analyzed for detailed lithostratigraphy and biostratigraphy. Both sections represent ancient seamount-capping carbonate buildups developed on a basaltic basement in a mid-oceanic environment. The occurrence of abundant Tethyan fusulines allows the recognition of well-defined biostratigraphic zonation in both sections and their mutual correlation. The Upper Guadalupian (Middle Permian) Lepidolina / Yabeina Zone is overlain conformably by the Lower Lopingian (Upper Permian) Codonofusiella – Reichelina Zone with a 13 m-thick transitional interval barren of index taxa. The Guadalupian–Lopingian (G–L) boundary is marked by the First Appearance Datum (FAD) of the Lopingian Codonofusiella – Reichelina assemblage in both sections. This study recognizes for the first time the G–L boundary horizon in a mid-oceanic shallow-water environment. In addition, the shallow-water carbonates in the study sections record the extinction of the Middle Permian large-sized fusuline family Verbeekinidae at the G–L boundary in mid-Panthalassa, as well as in shallow-water Tethyan shelf areas, demonstrating positively that the G–L boundary mass extinction occurred on a global scale. The abrupt elimination of large-shelled fusulines, followed by the domination of small-shelled fusulines may indicate that environmental stress occurred at the end of Guadalupian. The dying-out of symbiotic algae may have caused the selective extinction of the large-shelled fusulines.
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Fusuline biotic turnover across the Guadalupian–Lopingian (Middle–Upper Permian) boundary in mid-oceanic carbonate buildups: Biostratigraphy of accreted limestone in Japan
Journal of Asian Earth Sciences, 2005Co-Authors: Ayano Ota, Yukio IsozakiAbstract:Abstract Two sections in Upper Middle to Lower Upper Permian shallow-water limestones at Kamura and Akasaka in southwest Japan were analyzed for detailed lithostratigraphy and biostratigraphy. Both sections represent ancient seamount-capping carbonate buildups developed on a basaltic basement in a mid-oceanic environment. The occurrence of abundant Tethyan fusulines allows the recognition of well-defined biostratigraphic zonation in both sections and their mutual correlation. The Upper Guadalupian (Middle Permian) Lepidolina / Yabeina Zone is overlain conformably by the Lower Lopingian (Upper Permian) Codonofusiella – Reichelina Zone with a 13 m-thick transitional interval barren of index taxa. The Guadalupian–Lopingian (G–L) boundary is marked by the First Appearance Datum (FAD) of the Lopingian Codonofusiella – Reichelina assemblage in both sections. This study recognizes for the first time the G–L boundary horizon in a mid-oceanic shallow-water environment. In addition, the shallow-water carbonates in the study sections record the extinction of the Middle Permian large-sized fusuline family Verbeekinidae at the G–L boundary in mid-Panthalassa, as well as in shallow-water Tethyan shelf areas, demonstrating positively that the G–L boundary mass extinction occurred on a global scale. The abrupt elimination of large-shelled fusulines, followed by the domination of small-shelled fusulines may indicate that environmental stress occurred at the end of Guadalupian. The dying-out of symbiotic algae may have caused the selective extinction of the large-shelled fusulines.
Jian-wei Shen - One of the best experts on this subject based on the ideXlab platform.
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microbial carbonates as contributors to upper permian Guadalupian lopingian biostromes and reefs in carbonate platform margin setting ziyun county south china
Palaeogeography Palaeoclimatology Palaeoecology, 2005Co-Authors: Jian-wei ShenAbstract:Permian (Guadalupian and Lopingian) reefs in Ziyun County, southern Guizhou, southwestern China, occur in a carbonate platform margin setting. Guadalupian reefs (Maokouan) are characterized by sponges, calcimicrobes, microbialites (as microencrusters) and syndepositional calcite cement. Global sea level falling in the latest Guadalupian changed the reef biotopes. Lower Lopingian (Wuchiapingian) deposits reflect a rapid transgressive-regressive cycle; reefs were not developed during that time, although coral biostromes are common. However, microbial carbonates occur commonly in these biostromes, including dark-coloured, homogeneous microbialite, free-growing microbes, Shamovella and Archaeolithoporella (interpreted to be problematic microbial deposits). Upper Lopingian (Changhsingian) reefs were formed by sponges, microbialites, Shamovella, Archaeolithoporella, automicrite and syndepositional calcite cement. Common primary encrustations consist of thin, homogeneous, subparallel layers of Archaeolithoporella, which is an important reef builder particularly throughout the Lopingian reef succession. Secondary encrustations are characterized by dark-coloured, homogeneous microbialite containing thin thalli that alternate with light-coloured microspar/pseudospar. Reef-building organisms (e.g., sponges, Archaeolithoporella, calcimicrobes and hydrozoans) were bound, lithified and preserved by syndepositional calcite cement and microbially precipitated micrite (automicrite). In Changhsingian reefs of the Shitouzhai Limestone, microbial carbonate (e.g., micritic peloidal crusts and automicrite layers) encrusted the top, sides and undersides of in situ organisms and also grew on their upper surface as thick accumulations. Radiaxial fibrous calcite cement is present, but is not common. Abundant microbial carbonates in the Guadalupian to Lopingian reefs in Ziyun indicate that microbial precipitation of calcium carbonate played a vital role in the development of Permian reefs in this platform margin setting. (c) 2004 Elsevier B.V. All rights reserved.
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Microbial carbonates as contributors to Upper Permian (Guadalupian¿Lopingian) biostromes and reefs in carbonate platform margin setting, Ziyun County, South China
Palaeogeography Palaeoclimatology Palaeoecology, 2005Co-Authors: Jian-wei ShenAbstract:Permian (Guadalupian and Lopingian) reefs in Ziyun County, southern Guizhou, southwestern China, occur in a carbonate platform margin setting. Guadalupian reefs (Maokouan) are characterized by sponges, calcimicrobes, microbialites (as microencrusters) and syndepositional calcite cement. Global sea level falling in the latest Guadalupian changed the reef biotopes. Lower Lopingian (Wuchiapingian) deposits reflect a rapid transgressive-regressive cycle; reefs were not developed during that time, although coral biostromes are common. However, microbial carbonates occur commonly in these biostromes, including dark-coloured, homogeneous microbialite, free-growing microbes, Shamovella and Archaeolithoporella (interpreted to be problematic microbial deposits). Upper Lopingian (Changhsingian) reefs were formed by sponges, microbialites, Shamovella, Archaeolithoporella, automicrite and syndepositional calcite cement. Common primary encrustations consist of thin, homogeneous, subparallel layers of Archaeolithoporella, which is an important reef builder particularly throughout the Lopingian reef succession. Secondary encrustations are characterized by dark-coloured, homogeneous microbialite containing thin thalli that alternate with light-coloured microspar/pseudospar. Reef-building organisms (e.g., sponges, Archaeolithoporella, calcimicrobes and hydrozoans) were bound, lithified and preserved by syndepositional calcite cement and microbially precipitated micrite (automicrite). In Changhsingian reefs of the Shitouzhai Limestone, microbial carbonate (e.g., micritic peloidal crusts and automicrite layers) encrusted the top, sides and undersides of in situ organisms and also grew on their upper surface as thick accumulations. Radiaxial fibrous calcite cement is present, but is not common. Abundant microbial carbonates in the Guadalupian to Lopingian reefs in Ziyun indicate that microbial precipitation of calcium carbonate played a vital role in the development of Permian reefs in this platform margin setting. (c) 2004 Elsevier B.V. All rights reserved.
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Guadalupian algae-sponge reefs in siliciclastic environments—the reefs at Lengwu (South China) compared with the reef at Iwaizaki (Japan)
Facies, 2001Co-Authors: Jian-wei Shen, Toshio KawamuraAbstract:Guadalupian reefs occur locally in Guangxi, Guizhou, Yunnan and Western Zhejiang, South China. Two types of Guadalupian reefs can be recognized, one is developed in carbonate platforms, e.g. those in the juncture areas of Guangxi, Yunnan and Guizhou; the other occurs in a littoral clastic shelf. The Lengwu reef in Western Zhejiang is a representative of the latter type, which is a major topic of this paper. Lengwu algae-sponge reef, more than one hundred meters in thickness, are composed mainly of sponges, hydrozoans, algae, bryozoans, microbes and lime mud. Reef limestones sit on the mudstone interbedded with fine sandstone of the proximal prodelta facies and are overlain by coarse clasts of the delta front sediments. Lengwu reef displays a lens-shaped relief, dipping and thinning from the reef core, which is remarkably different from the surrounding sediments, showing a protruding relief. Sponges and microbe/algae form bafflestone, bindstone and framestone of the reef core facies. Fore-reef facies is characterized by lithoclastic rudstone and bioclastic packstone. Reef limestone sequence is composed of three cycles and controlled by sea level changes and sediment influx. Such reef is unique among the Guadalupian reefs in South China, but seems similar in some aspects to Iwaizaki reef limestones of south Kitakami in Japan. Algae and microbes growing around sponges to form rigid structure in Lengwu reef are a typical feature, which is distinctly different to Guadalupian reefs in a stable platform facies of Guizhou, Yunnan and Guangxi, South China.
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Guadalupian algae sponge reefs in siliciclastic environments the reefs at lengwu south china compared with the reef at iwaizaki japan
Facies, 2001Co-Authors: Jian-wei Shen, Toshio KawamuraAbstract:Guadalupian reefs occur locally in Guangxi, Guizhou, Yunnan and Western Zhejiang, South China. Two types of Guadalupian reefs can be recognized, one is developed in carbonate platforms, e.g. those in the juncture areas of Guangxi, Yunnan and Guizhou; the other occurs in a littoral clastic shelf. The Lengwu reef in Western Zhejiang is a representative of the latter type, which is a major topic of this paper. Lengwu algae-sponge reef, more than one hundred meters in thickness, are composed mainly of sponges, hydrozoans, algae, bryozoans, microbes and lime mud. Reef limestones sit on the mudstone interbedded with fine sandstone of the proximal prodelta facies and are overlain by coarse clasts of the delta front sediments. Lengwu reef displays a lens-shaped relief, dipping and thinning from the reef core, which is remarkably different from the surrounding sediments, showing a protruding relief. Sponges and microbe/algae form bafflestone, bindstone and framestone of the reef core facies. Fore-reef facies is characterized by lithoclastic rudstone and bioclastic packstone. Reef limestone sequence is composed of three cycles and controlled by sea level changes and sediment influx. Such reef is unique among the Guadalupian reefs in South China, but seems similar in some aspects to Iwaizaki reef limestones of south Kitakami in Japan. Algae and microbes growing around sponges to form rigid structure in Lengwu reef are a typical feature, which is distinctly different to Guadalupian reefs in a stable platform facies of Guizhou, Yunnan and Guangxi, South China.
