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| Titel |
Methods for Shale Gas Play Assessment: A Comparison between Silurian Longmaxi Shale and Mississippian Barnett Shale |
| VerfasserIn |
Songqi Pan, Caineng Zou, Zhi Yang |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250101033
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| Publikation (Nr.) |
 EGU/EGU2015-108.pdf |
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| Zusammenfassung |
| Based on field work, organic geochemical analyses and experimental testing, a six-property
assessment method for shale gas is proposed. These six properties include organic matter
properies, lithofacies, petrophysical properties, gas content, brittleness and local
stress field. Due to the features of continuous distribution over a large area and
low resource abundance in shale plays, a sweet spot should have these following
properties: a) TOC>2%; b) brittle minerals content (>40%) and clay minerals
(1.1%); d) porosity (>2%) and permeability (>0.0001mD), and
e) effective thickness (30m-50m). Applying these criteria in the Sichuan Basin,
the Silurian Longmaxi Shale consists of four prospecting sweet spots, including
blocks of Changning, Weiyuan, Zhaotong and Fushun-Yongchuan. Although these
four blocks have some similarities, different features were usually observed. After
comprehensive analyses using the six-property assessment method, the Fushun-Yongan
block ranks the most favorable sweet spot, followed by the Weiyuan block. For
the other two blocks, the Changning block is better than the Zhaotong block. By
comparing with the Mississippian Barnett Shale, characteristics that are crucial for a
high-yielding in the Sichuan Basin include a high content of organic matter (TOC>2.5%),
a moderate thermal maturity (Ro=0.4%~2%), a high content of brittle minerals
(quartz: 30%~45%), a high gas content (>2.5m3?t-1), and types I and II1 kerogen. |
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