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Title: Short-range, overpressure-driven methane migration in coarse-grained gas hydrate reservoirs

Abstract

Two methane migration mechanisms have been proposed for coarse-grained gas hydrate reservoirs: short-range diffusive gas migration and long-range advective fluid transport from depth. Herein we demonstrate that short-range fluid flow due to overpressure in marine sediments is a significant additional methane transport mechanism that allows hydrate to precipitate in large quantities in thick, coarse-grained hydrate reservoirs. Two-dimensional simulations demonstrate that this migration mechanism, short-range advective transport, can supply significant amounts of dissolved gas and is unencumbered by limitations of the other two end-member mechanisms. Here, short-range advective migration can increase the amount of methane delivered to sands as compared to the slow process of diffusion, yet it is not necessarily limited by effective porosity reduction as is typical of updip advection from a deep source.

Authors:
ORCiD logo [1];  [1];  [2];  [3]
  1. Univ. of Texas at Austin, Austin, TX (United States)
  2. The Ohio State Univ., Columbus, OH (United States)
  3. Observatory of Columbia Univ., Palisades, NY (United States)
Publication Date:
Research Org.:
Univ. of Texas at Austin, Austin, TX (United States)
Sponsoring Org.:
USDOE Office of Fossil Energy (FE)
OSTI Identifier:
1314040
Grant/Contract Number:
FE0013919
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Geophysical Research Letters
Additional Journal Information:
Journal Name: Geophysical Research Letters; Journal ID: ISSN 0094-8276
Publisher:
American Geophysical Union
Country of Publication:
United States
Language:
English
Subject:
58 GEOSCIENCES

Citation Formats

Nole, Michael, Daigle, Hugh, Cook, Ann E., and Malinverno, Alberto. Short-range, overpressure-driven methane migration in coarse-grained gas hydrate reservoirs. United States: N. p., 2016. Web. doi:10.1002/2016GL070096.
Nole, Michael, Daigle, Hugh, Cook, Ann E., & Malinverno, Alberto. Short-range, overpressure-driven methane migration in coarse-grained gas hydrate reservoirs. United States. doi:10.1002/2016GL070096.
Nole, Michael, Daigle, Hugh, Cook, Ann E., and Malinverno, Alberto. 2016. "Short-range, overpressure-driven methane migration in coarse-grained gas hydrate reservoirs". United States. doi:10.1002/2016GL070096. https://www.osti.gov/servlets/purl/1314040.
@article{osti_1314040,
title = {Short-range, overpressure-driven methane migration in coarse-grained gas hydrate reservoirs},
author = {Nole, Michael and Daigle, Hugh and Cook, Ann E. and Malinverno, Alberto},
abstractNote = {Two methane migration mechanisms have been proposed for coarse-grained gas hydrate reservoirs: short-range diffusive gas migration and long-range advective fluid transport from depth. Herein we demonstrate that short-range fluid flow due to overpressure in marine sediments is a significant additional methane transport mechanism that allows hydrate to precipitate in large quantities in thick, coarse-grained hydrate reservoirs. Two-dimensional simulations demonstrate that this migration mechanism, short-range advective transport, can supply significant amounts of dissolved gas and is unencumbered by limitations of the other two end-member mechanisms. Here, short-range advective migration can increase the amount of methane delivered to sands as compared to the slow process of diffusion, yet it is not necessarily limited by effective porosity reduction as is typical of updip advection from a deep source.},
doi = {10.1002/2016GL070096},
journal = {Geophysical Research Letters},
number = ,
volume = ,
place = {United States},
year = 2016,
month = 8
}

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Free Publicly Available Full Text
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