The Experts below are selected from a list of 1722 Experts worldwide ranked by ideXlab platform
Katja Meyer - One of the best experts on this subject based on the ideXlab platform.
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Slowed by sulphide
Nature Geoscience, 2012Co-Authors: Katja MeyerAbstract:The Triassic–Jurassic Period extinction marked a rapid turnover in the marine realm. Biomarkers in marine rocks suggest that the development of sulphidic conditions in the early Jurassic delayed marine recovery.
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Palaeontology: Slowed by sulphide
Nature Geoscience, 2012Co-Authors: Katja MeyerAbstract:The Triassic–Jurassic Period extinction marked a rapid turnover in the marine realm. Biomarkers in marine rocks suggest that the development of sulphidic conditions in the early Jurassic delayed marine recovery.
Hermann Munsch - One of the best experts on this subject based on the ideXlab platform.
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Lower–Middle Jurassic facies patterns in the NW Afghan–Tajik Basin of southern Uzbekistan and their geodynamic context
Geological Society London Special Publications, 2015Co-Authors: Franz T. Fürsich, Marie-françoise Brunet, Jean-luc Auxiètre, Hermann MunschAbstract:International audienceBased on 11 sections, the palaeoenvironments and depositional history of the NW Afghan–Tajik Basin in southern Uzbekistan have been reconstructed for the time interval of the Early Jurassic–Early Callovian. The earliest sediments, resting on Palaeozoic basement rocks, date from the Early Jurassic Period. Up to the end of the Early Bajocian time, more than 500 m of non-marine sediments accumulated as a result of extensional tectonics inducing active subsidence. In the Late Bajocian time interval, transgression led to the establishment of siliciclastic ramps that were influenced by storm processes. After a condensed unit in the Middle Bathonian, sedimentation resumed in an outer carbonate ramp–basinal setting as the subsidence rate outpaced the diminished siliciclastic sediment supply. The change from siliciclastic to carbonate sedimentation in the Middle Jurassic Period is thought to be multifactorial, reflecting levelling of relief in the hinterland, the subsidence moving to a thermally more quiet stage and a change from humid to arid climatic conditions. These features are also observed in the area of present-day Iran. Similarly, the timing of the transgression coincides with that in eastern and northern Iran, stressing the regional significance of this event
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Lower–Middle Jurassic facies patterns in the NW Afghan–Tajik Basin of southern Uzbekistan and their geodynamic context
Geological Society Special Publication, 2015Co-Authors: Franz T. Fürsich, Marie-françoise Brunet, Jean-luc Auxiètre, Hermann MunschAbstract:Based on 11 sections, the palaeoenvironments and depositional history of the NW Afghan–Tajik Basin in southern Uzbekistan have been reconstructed for the time interval of the Early Jurassic–Early Callovian. The earliest sediments, resting on Palaeozoic basement rocks, date from the Early Jurassic Period. Up to the end of the Early Bajocian time, more than 500 m of non-marine sediments accumulated as a result of extensional tectonics inducing active subsidence. In the Late Bajocian time interval, transgression led to the establishment of siliciclastic ramps that were influenced by storm processes. After a condensed unit in the Middle Bathonian, sedimentation resumed in an outer carbonate ramp–basinal setting as the subsidence rate outpaced the diminished siliciclastic sediment supply. The change from siliciclastic to carbonate sedimentation in the Middle Jurassic Period is thought to be multifactorial, reflecting levelling of relief in the hinterland, the subsidence moving to a thermally more quiet stage and a change from humid to arid climatic conditions. These features are also observed in the area of present-day Iran. Similarly, the timing of the transgression coincides with that in eastern and northern Iran, stressing the regional significance of this event.
Lorenz Schwark - One of the best experts on this subject based on the ideXlab platform.
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Methane release in the Early Jurassic Period (Reply)
Nature, 2006Co-Authors: David B Kemp, Anthony S Cohen, Lorenz SchwarkAbstract:Wignall et al . ^ 1 suggest that the abrupt negative δ^13C_org shifts that we recognize in our data set^ 2 could be localized features caused by recycling of isotopically light marine carbon. This overlooks two important lines of evidence^ 2 : that the early Toarcian negative δ^13C excursion is present in several sections around the world^ 3 , 4 , 5 , and that the excursion is recorded in terrestrial plant material^ 4 . These crucial observations together preclude the possibility that the event was restricted to a localized, marine environment.
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Palaeoceanography: Methane release in the Early Jurassic Period (Reply)
Nature, 2006Co-Authors: David B Kemp, Angela L Coe, Anthony S Cohen, Lorenz SchwarkAbstract:Wignall . 1 suggest that the abrupt negative δ13Corg shifts that we recognize in our data set2 could be localized features caused by recycling of isotopically light marine carbon. This overlooks two important lines of evidence2: that the early Toarcian negative δ13C excursion is present in several sections around the world3,4,5, and that the excursion is recorded in terrestrial plant material4. These crucial observations together preclude the possibility that the event was restricted to a localized, marine environment.
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astronomical pacing of methane release in the early Jurassic Period
Nature, 2005Co-Authors: David B Kemp, Angela L Coe, Anthony S Cohen, Lorenz SchwarkAbstract:Mudrocks now exposed at Port Mulgrave and Hawkser Bottoms on the North Yorkshire coast in the United Kingdom record conditions that prevailed during a time of rapid global climate change, 180 million years ago in the Early Jurassic Period. It is thought that extensive volcanism and changes in solar radiation triggered massive release of methane gas and catastrophic global warming. The carbon isotope data from the Yorkshire mudrocks reveal three rapid pulses of methane hydrate dissociation driven by astronomical changes: two coincide with the extinction of marine species. This shows how natural processes can cause abrupt environmental change in the presence of a sensitive climatic threshold in this case sea-floor methane hydrates poised to dissociate.
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Erratum: Astronomical pacing of methane release in the Early Jurassic Period
Nature, 2005Co-Authors: David B Kemp, Angela L Coe, Anthony S Cohen, Lorenz SchwarkAbstract:Nature 437, 396–399 (2005) In the labelling of Fig. 1 of this Letter, the spelling of ‘D. semicelatum’ was accidentally reversed to read ‘D. mutalecimes’. It appears correctly in the text.
Sebastian Apesteguia - One of the best experts on this subject based on the ideXlab platform.
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the oldest known snakes from the middle Jurassic lower cretaceous provide insights on snake evolution
Nature Communications, 2015Co-Authors: Michael W Caldwell, Randall L Nydam, Alessandro Palci, Sebastian ApesteguiaAbstract:The origin and evolution of snakes remain poorly understood. Here, the authors show that fossils previously described as anguimorph lizards are ancient snakes and demonstrate that they share features with snakes and lizards, which suggests great diversity of snakes by the Jurassic Period.
Jin Meng - One of the best experts on this subject based on the ideXlab platform.
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Corrigendum: A new arboreal haramiyid shows the diversity of crown mammals in the Jurassic Period
Nature, 2015Co-Authors: Xiaoting Zheng, Xiaoli Wang, Jin MengAbstract:Nature 500, 199–202 (2013); doi:10.1038/nature12353 In Fig. 2a of this Letter the tooth P3 should be horizontally flipped, as shown in Fig. 1 of this Corrigendum. We thank Z-X. Luo, T. Martin and C-F. Zhou for pointing out the error.
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Three new Jurassic euharamiyidan species reinforce early divergence of mammals
Nature, 2014Co-Authors: Shundong Bi, Yuanqing Wang, Xia Sheng, Jian Guan, Jin MengAbstract:The phylogeny of Allotheria, including Multituberculata and Haramiyida, remains unsolved and has generated contentious views on the origin and earliest evolution of mammals. Here we report three new species of a new clade, Euharamiyida, based on six well-preserved fossils from the Jurassic Period of China. These fossils reveal many craniodental and postcranial features of euharamiyidans and clarify several ambiguous structures that are currently the topic of debate. Our phylogenetic analyses recognize Euharamiyida as the sister group of Multituberculata, and place Allotheria within the Mammalia. The phylogeny suggests that allotherian mammals evolved from a Late Triassic (approximately 208 million years ago) Haramiyavia-like ancestor and diversified into euharamiyidans and multituberculates with a cosmopolitan distribution, implying homologous acquisition of many craniodental and postcranial features in the two groups. Our findings also favour a Late Triassic origin of mammals in Laurasia and two independent detachment events of the middle ear bones during mammalian evolution. Three new euharamiyidan species from the Jurassic Period of China are described, cementing the alliance with multituberculates and showing that the initial divergence between groups of extant mammals—monotremes on the one side, marsupials and placentals on the other—goes back to the Triassic Period. Haramiyids are extremely ancient fossil mammals until recently known only from teeth, and thought to be related to the extinct but extremely successful rodent-like multituberculates. The discovery of skulls and skeletons only added to the confusion, one report confirming and another questioning the alliance with multituberculates. Now Jin Meng and colleagues describe three new haramiyid species from the Jurassic Period of China, cementing the alliance with multituberculates and showing that the initial divergence between groups of mammals still with us — monotremes on one side, and marsupials and placentals on the other — is very ancient, dating back to the Triassic Period.
