Evolution of overmature marine shale porosity and implication to the free gas volume
The porosities of the Lower Cambrian shale and Upper Ordovician-Lower Silurian marine shale from the Sichuan Basin were analyzed using He-Hg porosimetry and field-emission scanning electron microscopy, to discuss the relationship of porosity to the organic matter maturity, total organic carbon (TOC)...
Main Authors: | , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
KeAi Communications Co., Ltd.
2013-12-01
|
Series: | Petroleum Exploration and Development |
Online Access: | http://www.sciencedirect.com/science/article/pii/S1876380413601111 |
id |
doaj-d8d6907d20834f698d5657b2e419c9fe |
---|---|
record_format |
Article |
spelling |
doaj-d8d6907d20834f698d5657b2e419c9fe2021-02-02T03:21:31ZengKeAi Communications Co., Ltd.Petroleum Exploration and Development1876-38042013-12-01406819824Evolution of overmature marine shale porosity and implication to the free gas volumeFeiyu WANG0Jing GUAN1Weiping FENG2Linyan BAO3State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China; College of Geosciences, China University of Petroleum, Beijing 102249, China; Corresponding authorState Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, ChinaState Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, ChinaState Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, ChinaThe porosities of the Lower Cambrian shale and Upper Ordovician-Lower Silurian marine shale from the Sichuan Basin were analyzed using He-Hg porosimetry and field-emission scanning electron microscopy, to discuss the relationship of porosity to the organic matter maturity, total organic carbon (TOC) and free gas volume. Overmature (Ro greater than 2%) shale samples with a TOC less than 5% display a positive correlation between TOC and porosity, but samples with a TOC greater than 5% display a limited increase in porosity with increasing TOC. The porosity of shale decreases generally with increasing maturity in the overmature stage. The free gas in porosity is the key factor for successful development of shale gas, and free gas volumes are controlled by porosity and gas saturation. Higher TOC shale has higher porosity and gas saturation. The Lower Silurian Longmaxi Formation shale has a higher TOC, Ro ranging from 2.0% to 2.3%, its porosity and gas saturation are significantly higher than the Lower Cambrian shale. The high free gas volume results in high production in the Lower Silurian Longmaxi Formation shale pay. Key words: marine shale, porosity, free gas, overmature, Sichuan Basinhttp://www.sciencedirect.com/science/article/pii/S1876380413601111 |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Feiyu WANG Jing GUAN Weiping FENG Linyan BAO |
spellingShingle |
Feiyu WANG Jing GUAN Weiping FENG Linyan BAO Evolution of overmature marine shale porosity and implication to the free gas volume Petroleum Exploration and Development |
author_facet |
Feiyu WANG Jing GUAN Weiping FENG Linyan BAO |
author_sort |
Feiyu WANG |
title |
Evolution of overmature marine shale porosity and implication to the free gas volume |
title_short |
Evolution of overmature marine shale porosity and implication to the free gas volume |
title_full |
Evolution of overmature marine shale porosity and implication to the free gas volume |
title_fullStr |
Evolution of overmature marine shale porosity and implication to the free gas volume |
title_full_unstemmed |
Evolution of overmature marine shale porosity and implication to the free gas volume |
title_sort |
evolution of overmature marine shale porosity and implication to the free gas volume |
publisher |
KeAi Communications Co., Ltd. |
series |
Petroleum Exploration and Development |
issn |
1876-3804 |
publishDate |
2013-12-01 |
description |
The porosities of the Lower Cambrian shale and Upper Ordovician-Lower Silurian marine shale from the Sichuan Basin were analyzed using He-Hg porosimetry and field-emission scanning electron microscopy, to discuss the relationship of porosity to the organic matter maturity, total organic carbon (TOC) and free gas volume. Overmature (Ro greater than 2%) shale samples with a TOC less than 5% display a positive correlation between TOC and porosity, but samples with a TOC greater than 5% display a limited increase in porosity with increasing TOC. The porosity of shale decreases generally with increasing maturity in the overmature stage. The free gas in porosity is the key factor for successful development of shale gas, and free gas volumes are controlled by porosity and gas saturation. Higher TOC shale has higher porosity and gas saturation. The Lower Silurian Longmaxi Formation shale has a higher TOC, Ro ranging from 2.0% to 2.3%, its porosity and gas saturation are significantly higher than the Lower Cambrian shale. The high free gas volume results in high production in the Lower Silurian Longmaxi Formation shale pay. Key words: marine shale, porosity, free gas, overmature, Sichuan Basin |
url |
http://www.sciencedirect.com/science/article/pii/S1876380413601111 |
work_keys_str_mv |
AT feiyuwang evolutionofovermaturemarineshaleporosityandimplicationtothefreegasvolume AT jingguan evolutionofovermaturemarineshaleporosityandimplicationtothefreegasvolume AT weipingfeng evolutionofovermaturemarineshaleporosityandimplicationtothefreegasvolume AT linyanbao evolutionofovermaturemarineshaleporosityandimplicationtothefreegasvolume |
_version_ |
1724307946176774144 |