The Paleocene-Eocene Thermal Maximum(PETM) event was a dramatic global warming w55.93 Ma ago that resulted in biological extinction events, lithological changes, and major deviations in σ13 C and σ18 O.The southwest...The Paleocene-Eocene Thermal Maximum(PETM) event was a dramatic global warming w55.93 Ma ago that resulted in biological extinction events, lithological changes, and major deviations in σ13 C and σ18 O.The southwestern Tarim Basin of China exposes successive Paleogene strata as a result of Tethys evolution and is considered an ideal region for PETM research.Based on calcareous nannoplankton biostratigraphy, we also used stable isotopes and XRD to analyse the Paleocene-Eocene transition in the Tarim Basin. At the Bashibulake Section, the PETM interval is characterized by(1) an abrupt negative shifts in σ13 C_(org), σ13 C_(carb) and σ18 O(-3%, -4.5% and -3%respectively);(2) an obvious negative correlation between the K-mode(Discoaster, Fasciculithus, Ericsonia, Sphenolithus and Rhomboaster) and r-mode(Biscutum, Chiasmolithus, Toweius) nannofossil taxa coincident with a robust Rhomboaster-Discoaster assemblage; and(3) a significant increase in the percentage of detrital input along with an increase in gypsum content. In the upper part of the Qimugen Formation Micrantholithus and Braarudosphaera are commonly found right up to the top where most of the nannofloras suffer a sharp decrease. In the overlying Gaijitage Formation, calcareous nannofossils disappear completely. These events indicate that the southwestern Tarim Basin was a warm shallow continental shelf during the deposition of the Qimugen Formation. From the early Eocene, the environment changed conspicuously. Evaporation increased and sea level fell, which led to an acid climate.This climate mode continued within the youngest unit studied, the Gaijitage Formation, characterized by the deposition of thick evaporates. Consequently, most of the marine plankton, i.e. calcareous nannoplankton, became disappear, because of the significant climate shift.展开更多
A biostratigraphic study on calcareous nannofossils from the CM3D06 Co-rich ferromanganese crust from the Magellan seamounts in the northwestern Pacific enabled estimation of depositional age. The bio-imprinting of ca...A biostratigraphic study on calcareous nannofossils from the CM3D06 Co-rich ferromanganese crust from the Magellan seamounts in the northwestern Pacific enabled estimation of depositional age. The bio-imprinting of calcareous nannofossils and other fossil species suggests six age ranges for the nannofossils： late Cretaceous, late Paleocene, （early, middle, late） Eocene, middle Miocene, late Pliocene, and Pleistocene. Gas chromatography （GC） and gas chromatography-mass spectrometry （GC-MS） were used to test the Co-rich crusts, and a variety of molecular fossils were detected, such as chloroform bituminous ＂A＂ , n-alkane, isoprenoid and sterol. Peak carbon and molecular indices （such as C23-/C24＋, CPI, Pr/Ph, Pr/nC17, Ph/nCxs and j13C） indicate that the parent organic matter is dominated by marine phytoplankton and thallogen whereas there is little input of terrestrial organic matter. Researches on calcareous nannofossils, molecular fossils and molecular organic geochemistry data reveal that the Paleocene/Eocene （P/E） global event is recorded in the cobalt- rich crusts from the northwestern Pacific Ocean. A succession of biomes can be observed near the 85 mm boundary （about 55 Ma）, i.e., the disappearance of the late Cretaceous Watznaueria barnesae and Zigodicus spiralis, and Broisonia parka microbiotas above the P/E boundary, and the bloom of Coccolithus formosus, Discoaster multiradiatus, Discoaster mohleri and Discoaster sp. below the boundary. Typical parameters of molecular fossils, such as saturated hydrocarbon components and carbon-number maxima, Pr/Ph, Pr/C17, Ph/C18, distribution types of sterols, Ts/Tm ratios and bacterial hopane, also exhibit dramatic changes near the P/E boundary. These integrated results illustrate that the biome succession of calcareous nannofossils, relative content of molecular fossils and molecular indices in the cobalt-rich crusts near the 85 mm boundary faithfully record the P/E global event.展开更多
A new section at Jebel Gorraa,in northern Tunisia,contains the Paleocene-Eocene transition interval.Sample analysis of the section delivers abundant and diverse microfauna of planktonic and benthic foraminifera.Biostr...A new section at Jebel Gorraa,in northern Tunisia,contains the Paleocene-Eocene transition interval.Sample analysis of the section delivers abundant and diverse microfauna of planktonic and benthic foraminifera.Biostratigraphically,the Acarinina sibaiyaensis index-species is identified for the first time in this region,which allows us to specify the location of the Paleocene-Eocene boundary as well as the first E1 biozone of the lower Eocene.Samples from this biozone contain calcitic tests poorly preserved with an enrichment of iron oxide signifying a period of upheaval in local marine environments linked to the global warming of the Paleocene-Eocene Thermal Maximum （PETM）,the marker for the P/E boundary.展开更多
This paper investigates the biostratigraphy of the Palaeocene-Lower Eocene sequences in the Bibi Hakimeh 2 subsurface/subterranean sections located in the Bibi Hakimeh Oil Field. The Palaeocene-Lower Eocene sequences ...This paper investigates the biostratigraphy of the Palaeocene-Lower Eocene sequences in the Bibi Hakimeh 2 subsurface/subterranean sections located in the Bibi Hakimeh Oil Field. The Palaeocene-Lower Eocene sequences are induced as part of the Pabdeh Formation. They are 49 m in thickness and are made up of clayey limestone with chert intercalations. Biostratigraphic investigations identified 10 genera and 51 species of Planktonic Foraminifera which with respect to the specific planktonic species and according to the newest Wade Biozonation led to the determination of 9 biozones and 4 subzones. The Palaeocene-Early Eocene biostratigraphic boundary determined previously in accordance with the Wynd Biozonation was reviewed with respect to the new biozonation. Moreover, the impression of the PETM on the Planktonic Foraminifera found in the Bibi Hakimeh subsurface section, has been occurred at P/E boundary on global scale was studied. Based on this research we can conclude the P/E biostratigraphic boundary border is occurred ranges between 2125 - 2124 meters in Pabdeh formation.展开更多
Too many climate committees, conferences, articles and publications continue to suggest a one and a half (1.5<span style="white-space:nowrap;">°</span>C) to two degrees (2<span style=&quo...Too many climate committees, conferences, articles and publications continue to suggest a one and a half (1.5<span style="white-space:nowrap;">°</span>C) to two degrees (2<span style="white-space:nowrap;">°</span>C) Celsius as an achievable global limit to climate changes without establishment of any causal link to the proposed anti-warming mechanism. A comprehensive review has found instead that observationally informed projections of climate science underlying climate change offer a different outlook of five to six-degree (5<span style="white-space:nowrap;">°</span>C - 6<span style="white-space:nowrap;">°</span>C) increase as “most accurate” with regard to present trends, climate history and models, yielding the most likely outcome for 2100. The most causative triad for the present warming trend from 1950 to the present is identified in this paper: 1) the tripling (3×) of world population;2) the quadrupling (4×) of carbon emissions;and 3) the quintupling (5×) of the world energy consumption. This paper presents a quantitative, linear global temperature correlation to carbon dioxide levels that has great predictive value, a short temporal feedback loop, and the finding that it is also reversible. The Vostok ice core temperature and CO2 values for the past 400,000 years, with past sea level estimates have produced the sufficiently evidential “Hansen’s Graph”. Detailed analysis results in an equation for global average temperature change and an indebted, long-term sea level rise, from even a 20 ppm of CO2 change above 290 ppm, commonly taken as a baseline for levels before 1950. Comparison to the well-known 800,000 year old Dome C ice core is also performed. The best-performing climate change models and observational analysis are seen to project more warming than the average model often relied upon. World atmosphere, temperature, and sea level trends for 2100 and beyond are analyzed. A laboratory experiment proves the dramatic heat-entrapment capability of CO<sub>2</sub> compared to pure air, which yields insights into the future global atmospheric system. Policy-relevant climate remediation, including gigaton carbon capture, zero and negative emissions and positive individual action, are reviewed and updated, with recommendations.展开更多
基金supported by grants from the U.S.National Science Foundation including EAR-8918023 and 0125502grants from the American Chemical Society including PRF36318-AC8 and 46858-AC8
基金financially supported in part by funds from the State Key Laboratory of Palaeobiology and Stratigraphy (Nanjing Institute of Geology and Palaeontology, CAS) (GBL215010)National Basic Research Program of China (973 Program, No. 2012CB822002)+3 种基金the National Natural Science Foundation of China (Nos. 41302008, 41172037)the Fundamental Research Funds for the Central Universities (53200859490)Science and Technology Innovation Fund of the China University of Geoscience (Beijing)the Beijing Higher Education Young Elite Teacher Project (YETP0665)
文摘The Paleocene-Eocene Thermal Maximum(PETM) event was a dramatic global warming w55.93 Ma ago that resulted in biological extinction events, lithological changes, and major deviations in σ13 C and σ18 O.The southwestern Tarim Basin of China exposes successive Paleogene strata as a result of Tethys evolution and is considered an ideal region for PETM research.Based on calcareous nannoplankton biostratigraphy, we also used stable isotopes and XRD to analyse the Paleocene-Eocene transition in the Tarim Basin. At the Bashibulake Section, the PETM interval is characterized by(1) an abrupt negative shifts in σ13 C_(org), σ13 C_(carb) and σ18 O(-3%, -4.5% and -3%respectively);(2) an obvious negative correlation between the K-mode(Discoaster, Fasciculithus, Ericsonia, Sphenolithus and Rhomboaster) and r-mode(Biscutum, Chiasmolithus, Toweius) nannofossil taxa coincident with a robust Rhomboaster-Discoaster assemblage; and(3) a significant increase in the percentage of detrital input along with an increase in gypsum content. In the upper part of the Qimugen Formation Micrantholithus and Braarudosphaera are commonly found right up to the top where most of the nannofloras suffer a sharp decrease. In the overlying Gaijitage Formation, calcareous nannofossils disappear completely. These events indicate that the southwestern Tarim Basin was a warm shallow continental shelf during the deposition of the Qimugen Formation. From the early Eocene, the environment changed conspicuously. Evaporation increased and sea level fell, which led to an acid climate.This climate mode continued within the youngest unit studied, the Gaijitage Formation, characterized by the deposition of thick evaporates. Consequently, most of the marine plankton, i.e. calcareous nannoplankton, became disappear, because of the significant climate shift.
基金supported by National Natural Science Foundation of China (Grant Nos. 41076072 and 40676025)
文摘A biostratigraphic study on calcareous nannofossils from the CM3D06 Co-rich ferromanganese crust from the Magellan seamounts in the northwestern Pacific enabled estimation of depositional age. The bio-imprinting of calcareous nannofossils and other fossil species suggests six age ranges for the nannofossils： late Cretaceous, late Paleocene, （early, middle, late） Eocene, middle Miocene, late Pliocene, and Pleistocene. Gas chromatography （GC） and gas chromatography-mass spectrometry （GC-MS） were used to test the Co-rich crusts, and a variety of molecular fossils were detected, such as chloroform bituminous ＂A＂ , n-alkane, isoprenoid and sterol. Peak carbon and molecular indices （such as C23-/C24＋, CPI, Pr/Ph, Pr/nC17, Ph/nCxs and j13C） indicate that the parent organic matter is dominated by marine phytoplankton and thallogen whereas there is little input of terrestrial organic matter. Researches on calcareous nannofossils, molecular fossils and molecular organic geochemistry data reveal that the Paleocene/Eocene （P/E） global event is recorded in the cobalt- rich crusts from the northwestern Pacific Ocean. A succession of biomes can be observed near the 85 mm boundary （about 55 Ma）, i.e., the disappearance of the late Cretaceous Watznaueria barnesae and Zigodicus spiralis, and Broisonia parka microbiotas above the P/E boundary, and the bloom of Coccolithus formosus, Discoaster multiradiatus, Discoaster mohleri and Discoaster sp. below the boundary. Typical parameters of molecular fossils, such as saturated hydrocarbon components and carbon-number maxima, Pr/Ph, Pr/C17, Ph/C18, distribution types of sterols, Ts/Tm ratios and bacterial hopane, also exhibit dramatic changes near the P/E boundary. These integrated results illustrate that the biome succession of calcareous nannofossils, relative content of molecular fossils and molecular indices in the cobalt-rich crusts near the 85 mm boundary faithfully record the P/E global event.
文摘A new section at Jebel Gorraa,in northern Tunisia,contains the Paleocene-Eocene transition interval.Sample analysis of the section delivers abundant and diverse microfauna of planktonic and benthic foraminifera.Biostratigraphically,the Acarinina sibaiyaensis index-species is identified for the first time in this region,which allows us to specify the location of the Paleocene-Eocene boundary as well as the first E1 biozone of the lower Eocene.Samples from this biozone contain calcitic tests poorly preserved with an enrichment of iron oxide signifying a period of upheaval in local marine environments linked to the global warming of the Paleocene-Eocene Thermal Maximum （PETM）,the marker for the P/E boundary.
文摘This paper investigates the biostratigraphy of the Palaeocene-Lower Eocene sequences in the Bibi Hakimeh 2 subsurface/subterranean sections located in the Bibi Hakimeh Oil Field. The Palaeocene-Lower Eocene sequences are induced as part of the Pabdeh Formation. They are 49 m in thickness and are made up of clayey limestone with chert intercalations. Biostratigraphic investigations identified 10 genera and 51 species of Planktonic Foraminifera which with respect to the specific planktonic species and according to the newest Wade Biozonation led to the determination of 9 biozones and 4 subzones. The Palaeocene-Early Eocene biostratigraphic boundary determined previously in accordance with the Wynd Biozonation was reviewed with respect to the new biozonation. Moreover, the impression of the PETM on the Planktonic Foraminifera found in the Bibi Hakimeh subsurface section, has been occurred at P/E boundary on global scale was studied. Based on this research we can conclude the P/E biostratigraphic boundary border is occurred ranges between 2125 - 2124 meters in Pabdeh formation.
文摘Too many climate committees, conferences, articles and publications continue to suggest a one and a half (1.5<span style="white-space:nowrap;">°</span>C) to two degrees (2<span style="white-space:nowrap;">°</span>C) Celsius as an achievable global limit to climate changes without establishment of any causal link to the proposed anti-warming mechanism. A comprehensive review has found instead that observationally informed projections of climate science underlying climate change offer a different outlook of five to six-degree (5<span style="white-space:nowrap;">°</span>C - 6<span style="white-space:nowrap;">°</span>C) increase as “most accurate” with regard to present trends, climate history and models, yielding the most likely outcome for 2100. The most causative triad for the present warming trend from 1950 to the present is identified in this paper: 1) the tripling (3×) of world population;2) the quadrupling (4×) of carbon emissions;and 3) the quintupling (5×) of the world energy consumption. This paper presents a quantitative, linear global temperature correlation to carbon dioxide levels that has great predictive value, a short temporal feedback loop, and the finding that it is also reversible. The Vostok ice core temperature and CO2 values for the past 400,000 years, with past sea level estimates have produced the sufficiently evidential “Hansen’s Graph”. Detailed analysis results in an equation for global average temperature change and an indebted, long-term sea level rise, from even a 20 ppm of CO2 change above 290 ppm, commonly taken as a baseline for levels before 1950. Comparison to the well-known 800,000 year old Dome C ice core is also performed. The best-performing climate change models and observational analysis are seen to project more warming than the average model often relied upon. World atmosphere, temperature, and sea level trends for 2100 and beyond are analyzed. A laboratory experiment proves the dramatic heat-entrapment capability of CO<sub>2</sub> compared to pure air, which yields insights into the future global atmospheric system. Policy-relevant climate remediation, including gigaton carbon capture, zero and negative emissions and positive individual action, are reviewed and updated, with recommendations.
