Basin evolution, configuration styles, and hydrocarbon accumulation of the South Atlantic conjugate margins

The basins of the South Atlantic passive margins are filled with early rifting stage lacustrine sediments (Barremian, 129–125 Ma), transitional lacustrine and marine sediments (Aptian, 125–113 Ma), and drift stage marine sediments since early Cretaceous (Albian, 113 Ma). The South Atlantic margins c...

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Main Authors: Zhixin Wen, Shu Jiang, Chengpeng Song, Zhaoming Wang, Zhengjun He
Format: Article
Language:English
Published: SAGE Publishing 2019-05-01
Series:Energy Exploration & Exploitation
Online Access:https://doi.org/10.1177/0144598719840751
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author Zhixin Wen
Shu Jiang
Chengpeng Song
Zhaoming Wang
Zhengjun He
author_facet Zhixin Wen
Shu Jiang
Chengpeng Song
Zhaoming Wang
Zhengjun He
author_sort Zhixin Wen
collection DOAJ
description The basins of the South Atlantic passive margins are filled with early rifting stage lacustrine sediments (Barremian, 129–125 Ma), transitional lacustrine and marine sediments (Aptian, 125–113 Ma), and drift stage marine sediments since early Cretaceous (Albian, 113 Ma). The South Atlantic margins can be divided into three segments by the Rio Grande Fracture Zone and the Ascension Fracture Zone according to variations in the basin evolution history and configuration style. The lacustrine shale and marine shale source rocks are developed in the rift stage and drift (post-rift) stage in the South Atlantic passive margins, respectively. The southern segment of the margins is dominated by the lacustrine sedimentary filling in the rifted stage overlain by a thin marine sag system as a regional seal, where the hydrocarbons are mainly accumulated in the structural-stratigraphic lacustrine reservoirs formed in the rift stage. The middle segment developed salty rift-sag-type basins with rift and sag systems and with salt deposited in the transitional intercontinental rift stage, where the lacustrine shale in the lower part of the rifted lacustrine sequence and the marine shale in the lower part of the sag sequence formed in the marine post-rift stage are high-quality source rocks. This segment in the middle is mainly dominated by pre-salt lacustrine carbonate and post-salt marine turbidite plays. The northern segment is characterized by sag-type basins with a narrowly and locally distributed rifted lacustrine system and its overlying widely distributed thick marine sag systems. Gravity-flow (mostly turbidite) marine sandstones as good reservoirs were extensively developed in the sag stage due to the narrow shelf and steep slope. The post-rift marine shales in the lower part of the sag sequence are the main source rocks in the northern segment and the hydrocarbons generated from these source rocks directly migrated to and accumulated in the deep marine turbidite sandstones in the same sag sequence formed in the drift stage. From southern segment to northern segment, source rocks and hydrocarbon accumulations tend to occur in the stratigraphically higher formations. The hydrocarbon accumulations in the southern segment are mainly distributed in the rifted lacustrine sequence while that in the northern segment primarily occur in the post-rift marine sequence.
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spelling doaj.art-4ea9f716efa34be18be62e05e7260a0a2022-12-22T00:28:18ZengSAGE PublishingEnergy Exploration & Exploitation0144-59872048-40542019-05-013710.1177/0144598719840751Basin evolution, configuration styles, and hydrocarbon accumulation of the South Atlantic conjugate marginsZhixin WenShu JiangChengpeng SongZhaoming WangZhengjun HeThe basins of the South Atlantic passive margins are filled with early rifting stage lacustrine sediments (Barremian, 129–125 Ma), transitional lacustrine and marine sediments (Aptian, 125–113 Ma), and drift stage marine sediments since early Cretaceous (Albian, 113 Ma). The South Atlantic margins can be divided into three segments by the Rio Grande Fracture Zone and the Ascension Fracture Zone according to variations in the basin evolution history and configuration style. The lacustrine shale and marine shale source rocks are developed in the rift stage and drift (post-rift) stage in the South Atlantic passive margins, respectively. The southern segment of the margins is dominated by the lacustrine sedimentary filling in the rifted stage overlain by a thin marine sag system as a regional seal, where the hydrocarbons are mainly accumulated in the structural-stratigraphic lacustrine reservoirs formed in the rift stage. The middle segment developed salty rift-sag-type basins with rift and sag systems and with salt deposited in the transitional intercontinental rift stage, where the lacustrine shale in the lower part of the rifted lacustrine sequence and the marine shale in the lower part of the sag sequence formed in the marine post-rift stage are high-quality source rocks. This segment in the middle is mainly dominated by pre-salt lacustrine carbonate and post-salt marine turbidite plays. The northern segment is characterized by sag-type basins with a narrowly and locally distributed rifted lacustrine system and its overlying widely distributed thick marine sag systems. Gravity-flow (mostly turbidite) marine sandstones as good reservoirs were extensively developed in the sag stage due to the narrow shelf and steep slope. The post-rift marine shales in the lower part of the sag sequence are the main source rocks in the northern segment and the hydrocarbons generated from these source rocks directly migrated to and accumulated in the deep marine turbidite sandstones in the same sag sequence formed in the drift stage. From southern segment to northern segment, source rocks and hydrocarbon accumulations tend to occur in the stratigraphically higher formations. The hydrocarbon accumulations in the southern segment are mainly distributed in the rifted lacustrine sequence while that in the northern segment primarily occur in the post-rift marine sequence.https://doi.org/10.1177/0144598719840751
spellingShingle Zhixin Wen
Shu Jiang
Chengpeng Song
Zhaoming Wang
Zhengjun He
Basin evolution, configuration styles, and hydrocarbon accumulation of the South Atlantic conjugate margins
Energy Exploration & Exploitation
title Basin evolution, configuration styles, and hydrocarbon accumulation of the South Atlantic conjugate margins
title_full Basin evolution, configuration styles, and hydrocarbon accumulation of the South Atlantic conjugate margins
title_fullStr Basin evolution, configuration styles, and hydrocarbon accumulation of the South Atlantic conjugate margins
title_full_unstemmed Basin evolution, configuration styles, and hydrocarbon accumulation of the South Atlantic conjugate margins
title_short Basin evolution, configuration styles, and hydrocarbon accumulation of the South Atlantic conjugate margins
title_sort basin evolution configuration styles and hydrocarbon accumulation of the south atlantic conjugate margins
url https://doi.org/10.1177/0144598719840751
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AT chengpengsong basinevolutionconfigurationstylesandhydrocarbonaccumulationofthesouthatlanticconjugatemargins
AT zhaomingwang basinevolutionconfigurationstylesandhydrocarbonaccumulationofthesouthatlanticconjugatemargins
AT zhengjunhe basinevolutionconfigurationstylesandhydrocarbonaccumulationofthesouthatlanticconjugatemargins