Journal
JOURNAL OF ASIAN EARTH SCIENCES
Volume 236, Issue -, Pages -Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.jseaes.2022.105317
Keywords
Carbon isotope fractionation; Atmospheric CO2 concentration; Early Tithonian Cooling Event (ETCE); Paleo-oceanography; Eastern Tethys
Categories
Funding
- National Natural Science Foundation of China [41572089, 41772105]
- Mianyang Normal University [QD2021A22]
- China Scholarship Council [IGCP 710]
- Austrian Academy of Sciences
Ask authors/readers for more resources
The study presents a high-resolution organic matter carbon isotope dataset from Upper Jurassic marine sedimentary rocks in the Qiangtang Basin, Tibet. The dataset provides insights into the response of the eastern Tethys to carbon cycle perturbations and reveals a cold period, fluctuating climate, and significant cooling event during the Late Jurassic. The findings are consistent with records from the Atlantic and western Tethys, and suggest possible connections to major magmatic events and changes in oceanic circulation patterns.
The Jurassic oceanographic and climatic evolution is considered to be related to the breakup of Pangaea. As a crucial component of the carbon cycle, atmospheric CO2 concentration (pCO(2)) has been postulated as a main driver for climate change during the Jurassic, and concomitant changes in paleo-oceanographic conditions occurred as a result. In this study, we present a high-resolution organic matter (kerogen) carbon isotope dataset (delta C-13(kerogen)) from Upper Jurassic marine sedimentary rocks in the Qiangtang Basin, Tibet. The (delta C-13(kerogen) result contains a genuine record concerning the response of the eastern Tethys to exogenic carbon cycle perturbations in both marine and atmospheric reservoirs and is also consistent with the high-resolution bulk carbonate and organic matter carbon-isotope records from the Atlantic and western Tethys. The relative fractionation of carbon isotopes in organic matter vs. carbonate species, defined as delta 13C ((delta C-13(carb)(delta C-13(kerogen)), and the secular trend of atmospheric pCO(2 )over the Late Jurassic that is calculated from the high-resolution (delta C-13(kerogen) values indicate a cold Callovian-Oxfordian transition, a long-term increasing but fluctuating Kimmeridgian and a prominent early Tithonian cooling event (ETCE). The pronounced temperature plateau during the late Kimmeridgian-early Tithonian was contemporaneous with the occurrence of major magmatic events during the Late Jurassic, while the ETCE has been possibly attributed to major changes in oceanic circulation patterns. Additionally, reconstructed atmospheric pCO(2) values show very small differences to values using phytane-and stomatal density-based pCO(2) calculations, providing an alternative estimate for accurate identification of the paleoclimatic framework of this enigmatic interval in the Mesozoic.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available