Elemental geochemistry of the Middle Jurassic shales in the northern Qaidam Basin, northwestern China: Constraints for tectonics and paleoclimate

The elemental geochemical characteristics of mudstones/shales are good tracers for indicating the evolution of tectonics, paleoenvironment, and paleoclimate. Based on the continuous sampling of drilling cores from the Middle Jurassic Dameigou and Shimengou Formations in the northern Qaidam Basin, th...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Hou Haihai, Liu Shujun, Shao Longyi, Li Yonghong, Zhao Ming’en, Wang Cui
Formato:	article
Lenguaje:	EN
Publicado:	De Gruyter 2021
Materias:	northern qaidam basin middle jurassic element geochemistry weathering paleoclimate Geology QE1-996.5
Acceso en línea:	https://doaj.org/article/35b7fe4b8e9742b7870aa376849b5e3e
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:35b7fe4b8e9742b7870aa376849b5e3e
record_format	dspace
spelling	oai:doaj.org-article:35b7fe4b8e9742b7870aa376849b5e3e2021-12-05T14:10:49ZElemental geochemistry of the Middle Jurassic shales in the northern Qaidam Basin, northwestern China: Constraints for tectonics and paleoclimate2391-544710.1515/geo-2020-0318https://doaj.org/article/35b7fe4b8e9742b7870aa376849b5e3e2021-11-01T00:00:00Zhttps://doi.org/10.1515/geo-2020-0318https://doaj.org/toc/2391-5447The elemental geochemical characteristics of mudstones/shales are good tracers for indicating the evolution of tectonics, paleoenvironment, and paleoclimate. Based on the continuous sampling of drilling cores from the Middle Jurassic Dameigou and Shimengou Formations in the northern Qaidam Basin, the major, trace, and rare earth elements of the 31 mudstones and shales were analyzed. The information on the evolution of tectonics, provenance, and paleoclimate during Middle Jurassic was also recovered. The results show that: (1) A couple of elements consisting of Sc, Y, V, Cr, Co, Ni, Cu, Zn, Th, and U are relatively enriched, indicating that the contents of siderophile and chalcophile elements are significantly high in the Middle Jurassic samples; (2) Changes in the chemical index of alteration, Ga/Rb, and K2O/Al2O3 ratios in the mudstone/shale samples suggest that the paleoclimate was changed from warm and humid in the early stage to cold and dry in the middle stage and to hot and arid in the late stage; (3) The Middle Jurassic provenance of the northern Qaidam Basin was predicted from upper crust and felsic rocks to the mixed felsic rocks and basic rocks; (4) The Middle Jurassic tectonic background was changed from passive continental margin to active continental margin and oceanic island arc. The paleoclimatic and paleogeographic evolution of northern Qaidam Basin were closely related to the surrounding paleo-oceanic and ancient plate activities. In the early stage of the Middle Jurassic, the extensional activity in the passive continental margin and the water vapor input was caused by the Tethys Ocean, resulting in a warm and humid paleoclimate. In the late stage of the Middle Jurassic, the tectonic background of the study area tended to be an oceanic island arc caused by compressive tectonic, which blocked the monsoon input and led to a hot and arid paleoclimate. The establishment of multiple geochemical profiles can provide a scientific basis for the climate changes in greenhouse–icehouses and source–sink systems of the Middle Jurassic in northwestern China.Hou HaihaiLiu ShujunShao LongyiLi YonghongZhao Ming’enWang CuiDe Gruyterarticlenorthern qaidam basinmiddle jurassicelement geochemistryweatheringpaleoclimateGeologyQE1-996.5ENOpen Geosciences, Vol 13, Iss 1, Pp 1448-1462 (2021)
institution	DOAJ
collection	DOAJ
language	EN
topic	northern qaidam basin middle jurassic element geochemistry weathering paleoclimate Geology QE1-996.5
spellingShingle	northern qaidam basin middle jurassic element geochemistry weathering paleoclimate Geology QE1-996.5 Hou Haihai Liu Shujun Shao Longyi Li Yonghong Zhao Ming’en Wang Cui Elemental geochemistry of the Middle Jurassic shales in the northern Qaidam Basin, northwestern China: Constraints for tectonics and paleoclimate
description	The elemental geochemical characteristics of mudstones/shales are good tracers for indicating the evolution of tectonics, paleoenvironment, and paleoclimate. Based on the continuous sampling of drilling cores from the Middle Jurassic Dameigou and Shimengou Formations in the northern Qaidam Basin, the major, trace, and rare earth elements of the 31 mudstones and shales were analyzed. The information on the evolution of tectonics, provenance, and paleoclimate during Middle Jurassic was also recovered. The results show that: (1) A couple of elements consisting of Sc, Y, V, Cr, Co, Ni, Cu, Zn, Th, and U are relatively enriched, indicating that the contents of siderophile and chalcophile elements are significantly high in the Middle Jurassic samples; (2) Changes in the chemical index of alteration, Ga/Rb, and K2O/Al2O3 ratios in the mudstone/shale samples suggest that the paleoclimate was changed from warm and humid in the early stage to cold and dry in the middle stage and to hot and arid in the late stage; (3) The Middle Jurassic provenance of the northern Qaidam Basin was predicted from upper crust and felsic rocks to the mixed felsic rocks and basic rocks; (4) The Middle Jurassic tectonic background was changed from passive continental margin to active continental margin and oceanic island arc. The paleoclimatic and paleogeographic evolution of northern Qaidam Basin were closely related to the surrounding paleo-oceanic and ancient plate activities. In the early stage of the Middle Jurassic, the extensional activity in the passive continental margin and the water vapor input was caused by the Tethys Ocean, resulting in a warm and humid paleoclimate. In the late stage of the Middle Jurassic, the tectonic background of the study area tended to be an oceanic island arc caused by compressive tectonic, which blocked the monsoon input and led to a hot and arid paleoclimate. The establishment of multiple geochemical profiles can provide a scientific basis for the climate changes in greenhouse–icehouses and source–sink systems of the Middle Jurassic in northwestern China.
format	article
author	Hou Haihai Liu Shujun Shao Longyi Li Yonghong Zhao Ming’en Wang Cui
author_facet	Hou Haihai Liu Shujun Shao Longyi Li Yonghong Zhao Ming’en Wang Cui
author_sort	Hou Haihai
title	Elemental geochemistry of the Middle Jurassic shales in the northern Qaidam Basin, northwestern China: Constraints for tectonics and paleoclimate
title_short	Elemental geochemistry of the Middle Jurassic shales in the northern Qaidam Basin, northwestern China: Constraints for tectonics and paleoclimate
title_full	Elemental geochemistry of the Middle Jurassic shales in the northern Qaidam Basin, northwestern China: Constraints for tectonics and paleoclimate
title_fullStr	Elemental geochemistry of the Middle Jurassic shales in the northern Qaidam Basin, northwestern China: Constraints for tectonics and paleoclimate
title_full_unstemmed	Elemental geochemistry of the Middle Jurassic shales in the northern Qaidam Basin, northwestern China: Constraints for tectonics and paleoclimate
title_sort	elemental geochemistry of the middle jurassic shales in the northern qaidam basin, northwestern china: constraints for tectonics and paleoclimate
publisher	De Gruyter
publishDate	2021
url	https://doaj.org/article/35b7fe4b8e9742b7870aa376849b5e3e
work_keys_str_mv	AT houhaihai elementalgeochemistryofthemiddlejurassicshalesinthenorthernqaidambasinnorthwesternchinaconstraintsfortectonicsandpaleoclimate AT liushujun elementalgeochemistryofthemiddlejurassicshalesinthenorthernqaidambasinnorthwesternchinaconstraintsfortectonicsandpaleoclimate AT shaolongyi elementalgeochemistryofthemiddlejurassicshalesinthenorthernqaidambasinnorthwesternchinaconstraintsfortectonicsandpaleoclimate AT liyonghong elementalgeochemistryofthemiddlejurassicshalesinthenorthernqaidambasinnorthwesternchinaconstraintsfortectonicsandpaleoclimate AT zhaomingen elementalgeochemistryofthemiddlejurassicshalesinthenorthernqaidambasinnorthwesternchinaconstraintsfortectonicsandpaleoclimate AT wangcui elementalgeochemistryofthemiddlejurassicshalesinthenorthernqaidambasinnorthwesternchinaconstraintsfortectonicsandpaleoclimate
_version_	1718371714056847360

Elemental geochemistry of the Middle Jurassic shales in the northern Qaidam Basin, northwestern China: Constraints for tectonics and paleoclimate

Ejemplares similares