Heterogeneity of alkaline lacustrine source rocks of the lower Permian Fengcheng Formation in the Mahu Sag, Junggar Basin, northwestern China

The alkaline lacustrine source rocks in the lower Permian Fengcheng Formation in the Mahu Sag, Junggar Basin, China, exhibit significant heterogeneity. However, most previous studies have focused on the vertical variability of the source rocks, and the lateral variability is poorly understood. This...

Full description

Bibliographic Details
Main Authors: Baoli Xiang, Wanyun Ma, Dan He, Yueyang Pan
Format: Article
Language:English
Published: SAGE Publishing 2023-03-01
Series:Energy Exploration & Exploitation
Online Access:https://doi.org/10.1177/01445987221117838
_version_ 1797934762545905664
author Baoli Xiang
Wanyun Ma
Dan He
Yueyang Pan
author_facet Baoli Xiang
Wanyun Ma
Dan He
Yueyang Pan
author_sort Baoli Xiang
collection DOAJ
description The alkaline lacustrine source rocks in the lower Permian Fengcheng Formation in the Mahu Sag, Junggar Basin, China, exhibit significant heterogeneity. However, most previous studies have focused on the vertical variability of the source rocks, and the lateral variability is poorly understood. This study investigated recently drilled samples of the Fengcheng Formation in the Manan area to assess the lateral variability of the source rocks. The geochemical characteristics of the Fengcheng Formation source rocks in the Manan area are variable, with low–high abundances of organic matter, which comprises types I–III kerogen that is mature to high-mature. These features differ from the typical Fengcheng Formation source rocks in the Wuxia–Fengcheng area, which have a high abundance of organic matter with substantial hydrocarbon and shale oil generation potential. Biomarker data show that the organic matter in the Fengcheng Formation source rocks in the Manan area is a mixture of higher plants, algae, and bacteria, which differs from the Wuxia–Fengcheng area where algae and bacteria are dominant. The Fengcheng Formation source rocks in the Manan area were deposited in an oxic to anoxic environment characterized by large variations in water salinity and stratification. Mudstones were deposited rather than carbonate rocks. This differs from the strongly reducing, hypersaline, and water-stratified depositional environment of the Fengcheng Formation source rocks in the Wuxia–Fengcheng area. These two areas are separated by the Dazhuluogou Fault, and there are no alkaline lacustrine deposits in the Manan area. The distribution of the alkaline lacustrine source rocks was controlled by the paleogeography and sedimentary environment, which was characterized by significant spatial heterogeneity.
first_indexed 2024-04-10T18:05:04Z
format Article
id doaj.art-89c8df5058ae4feb904ba58aff8a29fb
institution Directory Open Access Journal
issn 0144-5987
2048-4054
language English
last_indexed 2024-04-10T18:05:04Z
publishDate 2023-03-01
publisher SAGE Publishing
record_format Article
series Energy Exploration & Exploitation
spelling doaj.art-89c8df5058ae4feb904ba58aff8a29fb2023-02-02T13:34:09ZengSAGE PublishingEnergy Exploration & Exploitation0144-59872048-40542023-03-014110.1177/01445987221117838Heterogeneity of alkaline lacustrine source rocks of the lower Permian Fengcheng Formation in the Mahu Sag, Junggar Basin, northwestern ChinaBaoli XiangWanyun MaDan HeYueyang PanThe alkaline lacustrine source rocks in the lower Permian Fengcheng Formation in the Mahu Sag, Junggar Basin, China, exhibit significant heterogeneity. However, most previous studies have focused on the vertical variability of the source rocks, and the lateral variability is poorly understood. This study investigated recently drilled samples of the Fengcheng Formation in the Manan area to assess the lateral variability of the source rocks. The geochemical characteristics of the Fengcheng Formation source rocks in the Manan area are variable, with low–high abundances of organic matter, which comprises types I–III kerogen that is mature to high-mature. These features differ from the typical Fengcheng Formation source rocks in the Wuxia–Fengcheng area, which have a high abundance of organic matter with substantial hydrocarbon and shale oil generation potential. Biomarker data show that the organic matter in the Fengcheng Formation source rocks in the Manan area is a mixture of higher plants, algae, and bacteria, which differs from the Wuxia–Fengcheng area where algae and bacteria are dominant. The Fengcheng Formation source rocks in the Manan area were deposited in an oxic to anoxic environment characterized by large variations in water salinity and stratification. Mudstones were deposited rather than carbonate rocks. This differs from the strongly reducing, hypersaline, and water-stratified depositional environment of the Fengcheng Formation source rocks in the Wuxia–Fengcheng area. These two areas are separated by the Dazhuluogou Fault, and there are no alkaline lacustrine deposits in the Manan area. The distribution of the alkaline lacustrine source rocks was controlled by the paleogeography and sedimentary environment, which was characterized by significant spatial heterogeneity.https://doi.org/10.1177/01445987221117838
spellingShingle Baoli Xiang
Wanyun Ma
Dan He
Yueyang Pan
Heterogeneity of alkaline lacustrine source rocks of the lower Permian Fengcheng Formation in the Mahu Sag, Junggar Basin, northwestern China
Energy Exploration & Exploitation
title Heterogeneity of alkaline lacustrine source rocks of the lower Permian Fengcheng Formation in the Mahu Sag, Junggar Basin, northwestern China
title_full Heterogeneity of alkaline lacustrine source rocks of the lower Permian Fengcheng Formation in the Mahu Sag, Junggar Basin, northwestern China
title_fullStr Heterogeneity of alkaline lacustrine source rocks of the lower Permian Fengcheng Formation in the Mahu Sag, Junggar Basin, northwestern China
title_full_unstemmed Heterogeneity of alkaline lacustrine source rocks of the lower Permian Fengcheng Formation in the Mahu Sag, Junggar Basin, northwestern China
title_short Heterogeneity of alkaline lacustrine source rocks of the lower Permian Fengcheng Formation in the Mahu Sag, Junggar Basin, northwestern China
title_sort heterogeneity of alkaline lacustrine source rocks of the lower permian fengcheng formation in the mahu sag junggar basin northwestern china
url https://doi.org/10.1177/01445987221117838
work_keys_str_mv AT baolixiang heterogeneityofalkalinelacustrinesourcerocksofthelowerpermianfengchengformationinthemahusagjunggarbasinnorthwesternchina
AT wanyunma heterogeneityofalkalinelacustrinesourcerocksofthelowerpermianfengchengformationinthemahusagjunggarbasinnorthwesternchina
AT danhe heterogeneityofalkalinelacustrinesourcerocksofthelowerpermianfengchengformationinthemahusagjunggarbasinnorthwesternchina
AT yueyangpan heterogeneityofalkalinelacustrinesourcerocksofthelowerpermianfengchengformationinthemahusagjunggarbasinnorthwesternchina