Formation mechanisms and sequence response of authigenic grain-coating chlorite: evidence from the Upper Triassic Xujiahe Formation in the southern Sichuan Basin, China

Abstract Authigenic grain-coating chlorite is widely distributed in the clastic rocks of many sedimentary basins around the world. These iron minerals were mainly derived from flocculent precipitates formed when rivers flow into the ocean, especially in deltaic environments with high hydrodynamic co...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Yu Yu, Liang-Biao Lin, Jian Gao
Formato:	article
Lenguaje:	EN
Publicado:	KeAi Communications Co., Ltd. 2016
Materias:	Sichuan Basin Xujiahe Formation Grain-coating chlorite Glauconite Pyrite Science Q Petrology QE420-499
Acceso en línea:	https://doaj.org/article/0a3b019c1bd84ca8ae9bcc735ac336ee
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:0a3b019c1bd84ca8ae9bcc735ac336ee
record_format	dspace
spelling	oai:doaj.org-article:0a3b019c1bd84ca8ae9bcc735ac336ee2021-12-02T02:18:10ZFormation mechanisms and sequence response of authigenic grain-coating chlorite: evidence from the Upper Triassic Xujiahe Formation in the southern Sichuan Basin, China10.1007/s12182-016-0125-21672-51071995-8226https://doaj.org/article/0a3b019c1bd84ca8ae9bcc735ac336ee2016-11-01T00:00:00Zhttp://link.springer.com/article/10.1007/s12182-016-0125-2https://doaj.org/toc/1672-5107https://doaj.org/toc/1995-8226Abstract Authigenic grain-coating chlorite is widely distributed in the clastic rocks of many sedimentary basins around the world. These iron minerals were mainly derived from flocculent precipitates formed when rivers flow into the ocean, especially in deltaic environments with high hydrodynamic conditions. At the same time, sandstone sequences with grain-coating chlorites also tend to have relatively high glauconite and pyrite content. EPMA composition analysis shows that glauconites with “high Al and low Fe” content indicate slightly to semi-saline marine environments with weak alkaline and weakly reducing conditions. By analyzing the chlorite-containing sandstone bodies of the southern Sichuan Xujiahe Formation, this study found that chlorite was mainly distributed in sedimentary microfacies, including underwater distributary channels, distributary channels, shallow lake sandstone dams, and mouth bars. Chlorite had a tendency to form in the upper parts of sandstone bodies with signs of increased base level, representing the influence of marine (lacustrine) transgression. This is believed to be influenced by megamonsoons in the Middle and Upper Yangtze Region during the Late Triassic Epoch. During periods of abundant precipitation, river discharges increased and more Fe particulates flowed into the ocean (lake). In the meantime, increases or decreases in lake level were only affected by precipitation for short periods of time. The sedimentary environment shifted from weakly oxidizing to weak alkaline, weakly reducing conditions as sea level increased, and Fe-rich minerals as authigenic chlorite and glauconite began to form and deposit.Yu YuLiang-Biao LinJian GaoKeAi Communications Co., Ltd.articleSichuan BasinXujiahe FormationGrain-coating chloriteGlauconitePyriteScienceQPetrologyQE420-499ENPetroleum Science, Vol 13, Iss 4, Pp 657-668 (2016)
institution	DOAJ
collection	DOAJ
language	EN
topic	Sichuan Basin Xujiahe Formation Grain-coating chlorite Glauconite Pyrite Science Q Petrology QE420-499
spellingShingle	Sichuan Basin Xujiahe Formation Grain-coating chlorite Glauconite Pyrite Science Q Petrology QE420-499 Yu Yu Liang-Biao Lin Jian Gao Formation mechanisms and sequence response of authigenic grain-coating chlorite: evidence from the Upper Triassic Xujiahe Formation in the southern Sichuan Basin, China
description	Abstract Authigenic grain-coating chlorite is widely distributed in the clastic rocks of many sedimentary basins around the world. These iron minerals were mainly derived from flocculent precipitates formed when rivers flow into the ocean, especially in deltaic environments with high hydrodynamic conditions. At the same time, sandstone sequences with grain-coating chlorites also tend to have relatively high glauconite and pyrite content. EPMA composition analysis shows that glauconites with “high Al and low Fe” content indicate slightly to semi-saline marine environments with weak alkaline and weakly reducing conditions. By analyzing the chlorite-containing sandstone bodies of the southern Sichuan Xujiahe Formation, this study found that chlorite was mainly distributed in sedimentary microfacies, including underwater distributary channels, distributary channels, shallow lake sandstone dams, and mouth bars. Chlorite had a tendency to form in the upper parts of sandstone bodies with signs of increased base level, representing the influence of marine (lacustrine) transgression. This is believed to be influenced by megamonsoons in the Middle and Upper Yangtze Region during the Late Triassic Epoch. During periods of abundant precipitation, river discharges increased and more Fe particulates flowed into the ocean (lake). In the meantime, increases or decreases in lake level were only affected by precipitation for short periods of time. The sedimentary environment shifted from weakly oxidizing to weak alkaline, weakly reducing conditions as sea level increased, and Fe-rich minerals as authigenic chlorite and glauconite began to form and deposit.
format	article
author	Yu Yu Liang-Biao Lin Jian Gao
author_facet	Yu Yu Liang-Biao Lin Jian Gao
author_sort	Yu Yu
title	Formation mechanisms and sequence response of authigenic grain-coating chlorite: evidence from the Upper Triassic Xujiahe Formation in the southern Sichuan Basin, China
title_short	Formation mechanisms and sequence response of authigenic grain-coating chlorite: evidence from the Upper Triassic Xujiahe Formation in the southern Sichuan Basin, China
title_full	Formation mechanisms and sequence response of authigenic grain-coating chlorite: evidence from the Upper Triassic Xujiahe Formation in the southern Sichuan Basin, China
title_fullStr	Formation mechanisms and sequence response of authigenic grain-coating chlorite: evidence from the Upper Triassic Xujiahe Formation in the southern Sichuan Basin, China
title_full_unstemmed	Formation mechanisms and sequence response of authigenic grain-coating chlorite: evidence from the Upper Triassic Xujiahe Formation in the southern Sichuan Basin, China
title_sort	formation mechanisms and sequence response of authigenic grain-coating chlorite: evidence from the upper triassic xujiahe formation in the southern sichuan basin, china
publisher	KeAi Communications Co., Ltd.
publishDate	2016
url	https://doaj.org/article/0a3b019c1bd84ca8ae9bcc735ac336ee
work_keys_str_mv	AT yuyu formationmechanismsandsequenceresponseofauthigenicgraincoatingchloriteevidencefromtheuppertriassicxujiaheformationinthesouthernsichuanbasinchina AT liangbiaolin formationmechanismsandsequenceresponseofauthigenicgraincoatingchloriteevidencefromtheuppertriassicxujiaheformationinthesouthernsichuanbasinchina AT jiangao formationmechanismsandsequenceresponseofauthigenicgraincoatingchloriteevidencefromtheuppertriassicxujiaheformationinthesouthernsichuanbasinchina
_version_	1718402511405056000

Formation mechanisms and sequence response of authigenic grain-coating chlorite: evidence from the Upper Triassic Xujiahe Formation in the southern Sichuan Basin, China

Ejemplares similares