scholarly journals Numerical History-Matching of Modeling and Actual Gas Production Behavior and Causes of the Discrepancy of the Nankai Trough Gas-Hydrate Production Test Cases

2021 ◽  
Author(s):  
Hisanao Ouchi ◽  
Koji Yamamoto ◽  
Koya Akamine ◽  
Satoshi Kano ◽  
Motoyoshi Naiki ◽  
...  
Keyword(s):  
Gas Hydrate ◽  
History Matching ◽  
Nankai Trough ◽  
Gas Production ◽  
Production Test ◽  
Test Cases ◽  
Production Behavior

Comparison of Simplistic and Geologically Descriptive Production Modeling for Natural-Gas Hydrate by Depressurization

SPE Journal ◽  
2019 ◽  
Vol 24 (02) ◽  
pp. 563-578 ◽  
Author(s):  
Yilong Yuan ◽  
Tianfu Xu ◽  
Yingli Xia ◽  
Xin Xin
Keyword(s):  
Gas Hydrate ◽  
History Matching ◽  
Nankai Trough ◽  
Flow Behavior ◽  
Test Site ◽  
Gas Production ◽  
Production Test ◽  
Hydrate Reservoir ◽  
Hydrate Saturation ◽  
Production Modeling

Summary Marine-gas-hydrate-drilling exploration at the Eastern Nankai Trough of Japan revealed the variable distribution of hydrate accumulations, which are composed of alternating beds of sand, silt, and clay in sediments, with vertically varying porosity, permeability, and hydrate saturation. The main purposes of this work are to evaluate gas productivity and identify the multiphase-flow behavior from the sedimentary-complex hydrate reservoir by depressurization through a conventional vertical well. We first established a history-matching model by incorporating the available geological data at the offshore-production test site in the Eastern Nankai Trough. The reservoir model was validated by matching the fluid-flow rates at a production well and temperature changes at a monitoring well during a field test. The modeling results indicate that the hydrate-dissociation zone is strongly affected by the reservoir heterogeneity and shows a unique dissociation front. The gas-production rate is expected to increase with time and reach the considerable value of 3.6 × 104 std m3/d as a result of the significant expansion of the dissociation zone. The numerical model, using a simplified description of porosity, permeability, and hydrate saturation, leads to significant underestimation of gas productivity from the sedimentary-complex hydrate reservoir. The results also suggest that the interbedded-hydrate-occurrence systems might be a better candidate for methane (CH4) gas extraction than the massive hydrate reservoirs.

Mechanical Response of Reservoir and Well Completion of the First Offshore Methane-Hydrate Production Test at the Eastern Nankai Trough: A Coupled Thermo-Hydromechanical Analysis

SPE Journal ◽  
2018 ◽  
Vol 24 (02) ◽  
pp. 531-546 ◽  
Author(s):  
Jun Yoneda ◽  
Akira Takiguchi ◽  
Toshimasa Ishibashi ◽  
Aya Yasui ◽  
Jiro Mori ◽  
...  
Keyword(s):  
Gas Hydrate ◽  
Mechanical Response ◽  
Nankai Trough ◽  
Water Pressure ◽  
Compressive Force ◽  
Gas Production ◽  
Production Test ◽  
Frictional Stress ◽  
Well Completion ◽  
Hydrate Saturation

Summary During gas production from offshore gas-HBS, there are concerns regarding the settlement of the seabed and the possibility that frictional stress will develop along the production casing. This frictional stress is caused by a change in the effective stress induced by water movement caused by depressurization and dissociation of hydrate as well as gas generation and thermal changes, all of which are interconnected. The authors have developed a multiphase-coupled simulator by use of a finite-element method named COTHMA. Stresses and deformation caused by gas-hydrate production near the production well and deep seabed were predicted using a multiphase simulator coupled with geomechanics for the offshore gas-hydrate-production test in the eastern Nankai Trough. Distributions of hydrate saturation, gas saturation, water pressure, gas pressure, temperature, and stresses were predicted by the simulator. As a result, the dissociation of gas hydrate was predicted within a range of approximately 10 m, but mechanical deformation occurred in a much wider area. The stress localization initially occurred in a sand layer with low hydrate saturation, and compression behavior appeared. Tensile stress was generated in and around the casing shoe as it was pulled vertically downward caused by compaction of the formation. As a result, the possibility of extensive failure of the gravel pack of the well completion was demonstrated. In addition, in a specific layer, where a pressure reduction progressed in the production interval, the compressive force related to frictional stress from the formation increased, and the gravel layer became thin. Settlement of the seafloor caused by depressurization for 6 days was within a few centimeters and an approximate 30 cm for 1 year of continued production.

Physical properties and sedimentological features of hydrate-bearing samples recovered from the first gas hydrate production test site on Daini-Atsumi Knoll around eastern Nankai Trough

2015 ◽  
Vol 66 ◽  
pp. 346-357 ◽  
Author(s):  
Kiyofumi Suzuki ◽  
Peter Schultheiss ◽  
Yoshihiro Nakatsuka ◽  
Takuma Ito ◽  
Kosuke Egawa ◽  
...  
Keyword(s):  
Physical Properties ◽  
Gas Hydrate ◽  
Nankai Trough ◽  
Test Site ◽  
Production Test

Numerical Study on Eastern Nankai Trough gas Hydrate Production Test

2014 ◽  
Author(s):  
Mingliang Zhou ◽  
Kenichi Soga ◽  
Ermao Xu ◽  
Shun Uchida ◽  
Koji Yamamoto
Keyword(s):  
Gas Hydrate ◽  
Nankai Trough ◽  
Numerical Study ◽  
Production Test

Mechanical properties of hydrate-bearing turbidite reservoir in the first gas production test site of the Eastern Nankai Trough

2015 ◽  
Vol 66 ◽  
pp. 471-486 ◽  
Author(s):  
Jun Yoneda ◽  
Akira Masui ◽  
Yoshihiro Konno ◽  
Yusuke Jin ◽  
Kosuke Egawa ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Nankai Trough ◽  
Test Site ◽  
Gas Production ◽  
Production Test

SS Gas Hydrate: Prediction of Production Test Performances in Eastern Nankai Trough Methane Hydrate Reservoirs Using 3D Reservoir Model

2010 ◽  
Author(s):  
Masanori Kurihara ◽  
Akihiko Sato ◽  
Hisanao Ouchi ◽  
Hideo Narita ◽  
Takao Ebinuma ◽  
...  
Keyword(s):  
Gas Hydrate ◽  
Methane Hydrate ◽  
Nankai Trough ◽  
Production Test ◽  
Reservoir Model ◽  
Hydrate Reservoirs

scholarly journals The second offshore production of methane hydrate in the Nankai Trough and gas production behavior from a heterogeneous methane hydrate reservoir

RSC Advances ◽  
2019 ◽  
Vol 9 (45) ◽  
pp. 25987-26013 ◽  
Author(s):  
K. Yamamoto ◽  
X.-X. Wang ◽  
M. Tamaki ◽  
K. Suzuki
Keyword(s):  
Data Acquisition ◽  
Methane Hydrate ◽  
Nankai Trough ◽  
Gas Production ◽  
Hydrate Reservoir ◽  
Offshore Production ◽  
Production Behavior ◽  
Data Acquisition Program ◽  
Made In

The second gas production attempt from a methane hydrate (MH) deposit in the eastern Nankai Trough area was made in 2017 with the intensive data acquisition program, and it revealed effects of reservoir characters on the MH dissociation behaviors.

Sign in / Sign up

Export Citation Format

Share Document