Updated on 2024/04/23

写真a

 
MORITA, Nobuo
 
Affiliation
Faculty of Science and Engineering
Job title
Professor Emeritus
Degree
Ph.D. ( 州立テキサス大学 )
Ph.D.(工学)州立テキサス大学

Research Experience

  • 1981
    -
    1995

    コノコ社部長級上級研究者

  • 1981
    -
    1995

    Conoco Inc., Research fellow

  • 1979
    -
    1981

    州立テキサス大学 研究員

  • 1979
    -
    1981

    University of Texas, Research Associate (]G0005[)

  • 1974
    -
    1977

    州立テキサス大学 研究員

  • 1974
    -
    1977

    University of Texas, Research Associate (]G0004[)

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Education Background

  •  
    -
    1974

    州立テキサス大学大学院   石油生産・地球科学研究室   石油工学科  

  •  
    -
    1974

    University of Texas at Austin   Production and Earth Science Division   Petroleum Enginerring Department  

  •  
    -
    1968

    The University of Tokyo  

  •  
    -
    1968

    University of Tokyo   Resource Development Department   Petroleum Engineering  

Professional Memberships

  •  
     
     

    米国石油技術協会

  •  
     
     

    日本素材学会

  •  
     
     

    石油技術協会

  •  
     
     

    資源・素材学会

  •  
     
     

    国際岩石工学協会

  •  
     
     

    アメリカ合衆国石油技術協会

  •  
     
     

    日本石油技術協会

  •  
     
     

    Japanese Society of Petroleum Engineering

  •  
     
     

    U.S. Society of Petroleum Engineering

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Research Interests

  • 環境資源工学

  • 資源開発工学

  • Resources and Environmental Engineerings

Awards

  • 1989年合衆国岩石工学技術協会賞(1989U.S.National Committee Rock Mechanics Award)

    1989  

  • 1989 USA Society of Rock Mechanics Applied Rock Mechanics Award

    1989  

 

Research Projects

  • 広域加熱法によるメタンハイドレート生産解析

    受託研究

    Project Year :

    2004
    -
    2006
     

  • Feasibility study of methane hydrate production with heat conduction from large areal heat source

    Funded Research

    Project Year :

    2004
    -
    2006
     

  • 坑井内に設置された鋼管の安定解析

    受託研究

    Project Year :

    2004
    -
    2005
     

  • Stability analysis of tubular strings installed in oil wells

    Funded Research

    Project Year :

    2004
    -
    2005
     

  • 出砂問題に対する基礎実験及び数値モデルの開発

    受託研究

    Project Year :

    2003
    -
     
     

  • 坑井安定解析に必要な諸種の数値モデルの開発及び解析

    受託研究

    Project Year :

    2002
    -
     
     

  • カラジ油田出砂解析

    受託研究

    Project Year :

    2000
    -
     
     

  • Sand production analysis for kafji reservoir

    Funded Research

    Project Year :

    2000
    -
     
     

  • アゼルバイジャンチラグ油田に対する出砂及び坑井安定解析

    受託研究

    Project Year :

    1999
    -
    2000
     

  • Sand production and borehole stability analysis for chirag field in Azer baijan

    Funded Research

    Project Year :

    1999
    -
    2000
     

  • 酸処理後の坑井安定解析

    受託研究

    Project Year :

    1996
    -
    1998
     

  • Borehole Stability analysis after acidization

    Funded Research

    Project Year :

    1996
    -
    1998
     

  • 油層生産経済解析

  • 有限要素法・境界要素法・体積要素法の応用

  • 油層出砂対策

  • 破壊の進んだ坑井破壊解析

  • 出砂問題に対する数値モデル開発

  • 広域加熱法によるメタンハイドレート生産法の経済解析

  • 坑内に設置された鋼管の安定解析

  • Development of Sand Production Models

  • Economic analysis of methane hydrate production with thermal conduction from large areal heat source

  • Stability analysis of tubular strings installed in oil wells

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Misc

  • Stability of an open hole completed in a limestone reservoir with and without acid treatments

    N Morita, T Doi, T Kinoshita

    SPE JOURNAL   10 ( 2 ) 105 - 114  2005.06

     View Summary

    Because a borehole in a limestone formation is more stable than expected, an openhole completion without a slotted/perforated liner has become popular recently. However, the following three items are not clear: (1) Why a borehole in a limestone formation is so stable, (2) why a borehole in a limestone formation can be completed without a liner regardless to the formation strength, and (3) the question of stability after acid treatments. To answer these questions, two types of laboratory experiments are conducted. One of them is a series of borehole stability experiments using 1.5- and 2.36- to 2.39-in.-diameter borehole in a 10.5x10.5x17.5-in. limestone blocks with polyaxial confining pressures simulating a horizontal well with three different principal in-situ stresses. Two types of limestones are used with and without borehole acid treatments and two borehole sizes are used to check the size effect. Another type of experiment is the acid squeezing experiment, in which 15% HCI acid solution is squeezed from one end of a cylindrical core and the change of porosity, permeability, and hardness are measured throughout the cores.
    The results showed the following new discoveries:
    1. The limestones have two distinct failure envelopes. The failure plastic strain is relatively small for normal shear failure, while it becomes as much as 10 times larger when a shear failure is induced after pore collapse.
    2. One of the limestones used in these experiments has only 1,751 psi UCS, yet the borehole was unexpectedly stable. The reason was that the borehole failure is induced by a shear failure after pore collapse. It is well known that pore collapse is induced within a formation during compaction; however, a shear failure after pore collapse has never been observed when one boundary is open like an open hole.
    3. The confining stress inducing borehole failure was not significantly different between hydrostatic and directional loadings. According to the Kirsch's solution, the directional load should significantly increase the stress concentration. It is well known that the nonlinearity of rock reduces the stress concentration induced by directional loading; however, the present experiments showed that the magnitude of the reduction of stress concentration was larger than expected.
    4. Wormholes stabilize boreholes even though acidizing weakens formation. Therefore, enhancing wormholes is recommened when a borehole in a limestone formation is acidized.
    Normally, because limestones are relatively strong, open holes are likely stable; however, the strength must be checked if they need to be completed without a linear protection. To help a reader applying the laboratory results to field problems, a guideline to complete an open hole without a liner protection in limestone reservoirs is provided, with calculation results using a nonlinear finite-element model.

  • Stability of an open hole completed in a limestone reservoir with and without acid treatments

    N Morita, T Doi, T Kinoshita

    SPE JOURNAL   10 ( 2 ) 105 - 114  2005.06

     View Summary

    Because a borehole in a limestone formation is more stable than expected, an openhole completion without a slotted/perforated liner has become popular recently. However, the following three items are not clear: (1) Why a borehole in a limestone formation is so stable, (2) why a borehole in a limestone formation can be completed without a liner regardless to the formation strength, and (3) the question of stability after acid treatments. To answer these questions, two types of laboratory experiments are conducted. One of them is a series of borehole stability experiments using 1.5- and 2.36- to 2.39-in.-diameter borehole in a 10.5x10.5x17.5-in. limestone blocks with polyaxial confining pressures simulating a horizontal well with three different principal in-situ stresses. Two types of limestones are used with and without borehole acid treatments and two borehole sizes are used to check the size effect. Another type of experiment is the acid squeezing experiment, in which 15% HCI acid solution is squeezed from one end of a cylindrical core and the change of porosity, permeability, and hardness are measured throughout the cores.
    The results showed the following new discoveries:
    1. The limestones have two distinct failure envelopes. The failure plastic strain is relatively small for normal shear failure, while it becomes as much as 10 times larger when a shear failure is induced after pore collapse.
    2. One of the limestones used in these experiments has only 1,751 psi UCS, yet the borehole was unexpectedly stable. The reason was that the borehole failure is induced by a shear failure after pore collapse. It is well known that pore collapse is induced within a formation during compaction; however, a shear failure after pore collapse has never been observed when one boundary is open like an open hole.
    3. The confining stress inducing borehole failure was not significantly different between hydrostatic and directional loadings. According to the Kirsch's solution, the directional load should significantly increase the stress concentration. It is well known that the nonlinearity of rock reduces the stress concentration induced by directional loading; however, the present experiments showed that the magnitude of the reduction of stress concentration was larger than expected.
    4. Wormholes stabilize boreholes even though acidizing weakens formation. Therefore, enhancing wormholes is recommened when a borehole in a limestone formation is acidized.
    Normally, because limestones are relatively strong, open holes are likely stable; however, the strength must be checked if they need to be completed without a linear protection. To help a reader applying the laboratory results to field problems, a guideline to complete an open hole without a liner protection in limestone reservoirs is provided, with calculation results using a nonlinear finite-element model.

  • Sand-Arch Strength Under Fluid Flow With and Without Capillary Pressure

    Hiroaki Arii, Y. Ito, E. Takano, N. Morita

    SPE 95812, 2005 SPE Annual Technical Conferences and Exhibition held in Dallas, 2005 SPE Annual Technical Conferences and Exhibition held in Dallas    2005

  • Collapse Resistance of Tubular Strings Under Geotectonic Load

    N. Morita, K. Kasahara, H. Hikida, Y. Ito

    SPE95691, 2005 SPE Annual Technical Conferences and Exhibition held in Dallas    2005

  • Sand-Arch Strength Under Fluid Flow With and Without Capillary Pressure

    Hiroaki Arii, Y. Ito, E. Takano, N. Morita

    SPE 95812, 2005 SPE Annual Technical Conferences and Exhibition held in Dallas, 2005 SPE Annual Technical Conferences and Exhibition held in Dallas    2005

  • Collapse Resistance of Tubular Strings Under Geotectonic Load

    N. Morita, K. Kasahara, H. Hikida, Y. Ito

    SPE95691, 2005 SPE Annual Technical Conferences and Exhibition held in Dallas    2005

  • Subsidence and Horizontal Earth Surface Movement During Reservoir Depletion for 3D Reservoirs With 3D Earth Surface

    Ikkou Suzuki, Nobuo Morita

    2004 SPE Annual Technical Conference Proceedings    2004

  • Well Orientation Effect on Borehole Stability

    Nobuo Morita

    2004 SPE Annual Technical Conference Proceedings    2004

  • Subsidence and Horizontal Earth Surface Movement During Reservoir Depletion for 3D Reservoirs With 3D Earth Surface

    Ikkou Suzuki, Nobuo Morita

    2004 SPE Annual Technical Conference Proceedings    2004

  • Well Orientation Effect on Borehole Stability

    Nobuo Morita

    2004 SPE Annual Technical Conference Proceedings    2004

  • Subsidence and Horizontal Movement Maps for Application of Reservoir Characterization

    SPE Annual Meeting Proceedings    2003

  • Subsidence and Horizontal Movement Maps for Application of Reservoir Characterization

    SPE Annual Meeting Proceedings    2003

  • Stability of an Openhole Completed in a Limestone Reservoir with and without Acid Treatments

    SPE JPT Journal    2002

  • 坑井ブレイクダウン圧力のサイズ効果について

    平成14年石油技術協会春季講演    2002

  • 石灰岩油層仕上げに対する孔明管の必要性について

    平成14年石油技術協会春季講演    2002

  • Stability of an Openhole Completed in a Limestone Reservoir With and Without Acid Treatments

    2002 SPE Annual Technical Conference and Exhibition, San Antonio Texas, U.S.A.   Proceedings  2002

  • Acid-Treatment Effects on Openhole Stability in Limestone

    Journal of Petroleum Technology, October, PP59-60   Volume 54-10  2002

  • Stability of an Openhole Completed in a Limestone Reservoir with and without Acid Treatments

    SPE JPT Journal    2002

  • 圧力減退した軟弱油層水平掘りに対する張り付き防止策

    平成13年度石油技術協会春季講演会    2001

  • ニューラルネットワークによる坑井不安定性問題解析

    平成13年度石油技術協会春季講演会    2001

  • 軟弱油層坑井仕上げ生産率比較

    平成13年度石油技術協会春季講演会    2001

  • 異方性のある水平地圧帯下のケーシング破壊について

    平成12年度石油技術協会春季講演会    2000

  • 圧入井に対する出砂問題対策

    平成12年度石油技術協会春季講演会    2000

  • 3次元坑井安定解析モデルにおける有限要素法境界要素法の計算効率比較

    平成11年度石油技術協会春季講演    1999

  • ケーシングシューテストの安全性について

    平成11年度石油技術協会春季講演    1999

  • 垂直井の出砂履歴から水平坑井の出砂履歴の予測

    平成11年度石油技術協会春季講演    1999

  • Application of Roservoir streugth Characterization and Formation Failure Modeling To Analyze Sand Prodaction Potential and To Formalate Sand Control Strategies for a Series of North Sea Gas Reservoirs

    1998SPE Annual Technical Conference Proceedings SPE48979, New Orleans, Lonisiana    1998

  • Guidelines for Solving Sand Problems in Water Injection Wells

    1998SPE International Symposium on Formation Damage Control    1998

  • Fracturing, Frac Packing, and Formation Failure Confrol : Can Screenless Conpletions Prevent Sand Production?

    SPE Drilling & Completion Journal, September 1998   /,157-162  1998

  • Prediction of Sand problems of a Horizontal Well from Sand Production Histories of Perforated Cased Wells

    SPE48975,1998 SPE Annual Conference, New Orleans, Lauisioana 1998    1998

  • Guidelines for Solving Sand Problems in Water Injection Wells

    Proceeding:1998 SPE(Society of Petroleum Engineers) International Symposium on Formation Damage Control   pp189-200  1998

  • Predietion of Sand Problems of a Horizontal Well from Sand Production Histories of perforated cased Wells

    proceedings of 1998 Annual Technical Conference and Exhibition   P.113-119  1998

  • Fractring, Frac Packing, and Formation Failure Control: Can Screeenless Completions Prevent Sand Production?

    SPE Drillina&Completion Journal    1998

  • Application of Roservoir streugth Characterization and Formation Failure Modeling To Analyze Sand Prodaction Potential and To Formalate Sand Control Strategies for a Series of North Sea Gas Reservoirs

    1998SPE Annual Technical Conference Proceedings SPE48979, New Orleans, Lonisiana    1998

  • Guidelines for Solving Sand Problems in Water Injection Wells

    1998SPE International Symposium on Formation Damage Control    1998

  • Fracturing, Frac Packing, and Formation Failure Confrol : Can Screenless Conpletions Prevent Sand Production?

    SPE Drilling & Completion Journal, September 1998   /,157-162  1998

  • Prediction of Sand problems of a Horizontal Well from Sand Production Histories of Perforated Cased Wells

    SPE48975,1998 SPE Annual Conference, New Orleans, Lauisioana 1998    1998

  • 生産問題に適した不規則格子数値モデルの比較(With 大竹真由)

    平成9年度石油技術協会春季講演会    1997

  • スクリーンレスフラックパッキング使用法のガイドライン

    平成9年度石油技術協会春季講演会    1997

  • 室内実験に見られる逸泥圧の予測と坑井周辺状態

    平成9年度石油技術協会春季講演会    1997

  • 逸泥防止剤の逸泥圧に対する影響

    平成9年度石油技術協会春季講演会    1997

  • Safety of Casing-Shoe Test and Casing-Shoe Integrity After Testing

    SPE(Society of Petroleum Engineers) Drilling and Completion Journal,   pp266-274  1997

  • Barchole Brcahdourn Pressure with Drilling Fluids Part 1.Empirical Results

    Int.Journal of Rock Mech Min.Sci.& Geomech.Abst.1996   vol33/,39-51  1996

    DOI

  • Oriental perforalior to precent casing collcpse for Highly Inclined Wells

    SPD Drilling and CompletionJournal Sept.1996   /,139-145  1996

  • Uncertainty Analysis of Borchole Stability Problems

    Proceedings,1996 SPE Annual Technical Curfesence and Exhibiton   /,555-542  1996

  • Borehole Breakdown Pressure with Drilling Fluids: Part 2. Semi-analytical solution to predict borehole breakdown pressure

    International Journal of Rock Mech. Min. Sci. & Geomech. Absr./Perganon press   33  1996

    DOI

  • Borehole Breakdown Pressure with Drilling Fluids: Part 1. Empirical results

    International Journal of Rock Mech. Min. Sci. & Geomech. Absr./Perganon press   33  1996

    DOI

  • Barchole Brcahdourn Pressure with Drilling Fluids Part 1.Empirical Results

    Int.Journal of Rock Mech Min.Sci.& Geomech.Abst.1996   vol33/,39-51  1996

    DOI

  • Oriental perforalior to precent casing collcpse for Highly Inclined Wells

    SPD Drilling and CompletionJournal Sept.1996   /,139-145  1996

  • Uncertainty Analysis of Borchole Stability Problems

    Proceedings,1996 SPE Annual Technical Curfesence and Exhibiton   /,555-542  1996

  • Uncertainty Analysis of Borehole Stability Problems (SPE30502)

    Proceedings, 1996/Society of Petroleum Engineers    1995

  • Oriented Perforation to Prevent Cashing Collapse for Highly Inclined Wells

    Drilling and Completion Journal, Sept. 1995/Society of Petroleum Engineers    1995

  • Field and Laboratory Verifications of Sand Production Prediction Models

    SPE Production Journal    1994

  • Rock Mechanics Aspects of Drilling and Completing Highly Inclined Wells in Weak Formations

    Invited paper (SPE 27983) : The Univ. of Tulsa/SPE Centennial Petroleum Engineering Symposium   /,265-276  1994

  • Field and Laboratory Verifications of Sand Production Prediction Models

    SPE Production Journal    1994

  • Rock Mechanics Aspects of Drilling and Completing Highly Inclined Wells in Weak Formations

    Invited paper (SPE 27983) : The Univ. of Tulsa/SPE Centennial Petroleum Engineering Symposium   /,265-276  1994

  • Transient Finite Element Code-Versatile Tool for Well Performance Analyses

    SPE 25878, SPE Rocky Mountain Regional Meeting    1993

  • Numerical Evaluation of Gravel Pack Damage

    SPE 25434, SPE Production Operation Symposium   /,287-416  1993

  • The Effect of Anisotropic Stress State on the Stability of Perforation Cavities

    with J. Tronvoll, International Rock Mechanics Journal   30/7,1085-1089  1993

    DOI

  • A New Approach to Preventing Lost Circulation while Drilling

    SPE24599, to be published in Oil/Gas Journal with Giin-fa Fuh 1993 SPE Annual Conference, Houston, Texas    1993

  • Core-based Horizontal or Highly Inclined Well Stability Analysis for Unconsolidated Formations

    SPE26332, 1993 SPE Annual Conference, Houston, Texas    1993

  • Transient Finite Element Code-Versatile Tool for Well Performance Analyses

    SPE 25878, SPE Rocky Mountain Regional Meeting    1993

  • Numerical Evaluation of Gravel Pack Damage

    SPE 25434, SPE Production Operation Symposium   /,287-416  1993

  • The Effect of Anisotropic Stress State on the Stability of Perforation Cavities

    with J. Tronvoll, International Rock Mechanics Journal   30/7,1085-1089  1993

    DOI

  • A New Approach to Preventing Lost Circulation while Drilling

    SPE24599, to be published in Oil/Gas Journal with Giin-fa Fuh 1993 SPE Annual Conference, Houston, Texas    1993

  • Core-based Horizontal or Highly Inclined Well Stability Analysis for Unconsolidated Formations

    SPE26332, 1993 SPE Annual Conference, Houston, Texas    1993

  • Rock Property Change During Reservoir Compaction

    SPE Formation Evaluation Journal   /,197-205  1992

  • Perforation Cavity Stability : Comprehensive Laboratory Experiments and Numerical Analysis

    with J. Trnovoll, SPE24799, 67th SPE Annual Technical Conference   /,339-349  1992

  • Rock Property Change During Reservoir Compaction

    SPE Formation Evaluation Journal   /,197-205  1992

  • Perforation Cavity Stability : Comprehensive Laboratory Experiments and Numerical Analysis

    with J. Trnovoll, SPE24799, 67th SPE Annual Technical Conference   /,339-349  1992

  • Safety of Casing Shoe Test and Casing Integrity After Testing

    SPE 22557, 1991, SPE Annual Conference   /,229-243  1991

  • Typical Sand Production Problems : Case Studies and Strategies for Sand Control

    SPE 22739, 1991 SPE Technical Annual Conference   /,9-  1991

  • Safety of Casing Shoe Test and Casing Integrity After Testing

    SPE 22557, 1991, SPE Annual Conference   /,229-243  1991

  • Typical Sand Production Problems : Case Studies and Strategies for Sand Control

    SPE 22739, 1991 SPE Technical Annual Conference   /,9-  1991

  • Three-Dimensional Well Medel Pre-processors for Reservoir Simulation with Horizontal and Curved Inclined Wells

    SPE20718, Proceedings of 1990 SPE Annual Technical Conference and Exhibition   /,49-64  1990

  • Theory of Lost Circulation Pressure

    SPE 20409, SPE Annual Technical Conference at New Orleans   /,43-58  1990

  • Three-Dimensional Well Medel Pre-processors for Reservoir Simulation with Horizontal and Curved Inclined Wells

    SPE20718, Proceedings of 1990 SPE Annual Technical Conference and Exhibition   /,49-64  1990

  • Theory of Lost Circulation Pressure

    SPE 20409, SPE Annual Technical Conference at New Orleans   /,43-58  1990

  • Parametric Study of Sand Production Prediction-Analytical Approach

    SPE Production Journal   /,25-34  1989

  • Realistic Sand Production Prediction-Numerical Approach

    SPE Production Journal   /,15-24  1989

  • A Quick Method To Determine Subsidence, Reservoir Compaction, and In-Situ Stress Induced by Reservoir Depletion

    JPT.   /,71-80  1989

  • Parametric Study of Sand Production Prediction-Analytical Approach

    SPE Production Journal   /,25-34  1989

  • Realistic Sand Production Prediction-Numerical Approach

    SPE Production Journal   /,15-24  1989

  • A Quick Method To Determine Subsidence, Reservoir Compaction, and In-Situ Stress Induced by Reservoir Depletion

    JPT.   /,71-80  1989

  • Stress-Intensity Factor and Fracture Cross-Sectional Shape Prediction From a 3-D Model for Hydraulically Induced Fractures

    JPT   /,1329-1342  1988

  • Stress-Intensity Factor and Fracture Cross-Sectional Shape Prediction From a 3-D Model for Hydraulically Induced Fractures

    JPT   /,1329-1342  1988

  • Gullfaks Subsea Wells : An Operators Implementation of a New Sand Production Model

    SPE16893, SPE Annual Technical Conference at Dallas   /,159-166  1987

  • The Engineering Approach to Sand Production Prediction

    SPE16890, SPE Annual Technical Conference at Dallas   /,151-158  1987

  • Gullfaks Subsea Wells : An Operators Implementation of a New Sand Production Model

    SPE16893, SPE Annual Technical Conference at Dallas   /,159-166  1987

  • The Engineering Approach to Sand Production Prediction

    SPE16890, SPE Annual Technical Conference at Dallas   /,151-158  1987

  • Type Curve Matching Techniques with Error Sensitivity Numbers

    SPE Production Journal   /,64-74  1986

  • Type Curve Matching Techniques with Error Sensitivity Numbers

    SPE Production Journal   /,64-74  1986

  • The Effect of Stress State and Temperature on Strain, Absolute Permeability, Electrical Resistivity, Porosity, and P-S Wave Velocities of a Consolidated Sandstone

    Published in 'Compressibility Phenomena in Subsidence' published by Engineering Foundation    1984

  • The Effect of Stress State and Temperature on Strain, Absolute Permeability, Electrical Resistivity, Porosity, and P-S Wave Velocities of a Consolidated Sandstone

    Published in 'Compressibility Phenomena in Subsidence' published by Engineering Foundation    1984

  • Stress State, Porosity, Permeability and Breakdown Pressue around a Borehole During Fluid Injection

    22nd U. S. Symposium on Rock Mechanics, MIT    1981

  • Stress State, Porosity, Permeability and Breakdown Pressue around a Borehole During Fluid Injection

    22nd U. S. Symposium on Rock Mechanics, MIT    1981

  • Three Dimensional Permeability Measurements

    Proceedings of the 1980 SPE Annual Technical Conference and Exhibition, SPE9377    1980

  • Relative Permeability Measurements of Rocks from the Texas Gulf Coast Geopressured-Geothermal Reservoir at Low Free Gas Saturations

    Transactions of the Geothermal Resources Council.   4/,369-372  1980

  • Compaction of Sands and Shales of Geopressured Zones

    Proceedings of the International Conference on Geo-technical and Environmental Aspects of Geopressure Energy   /,93-107  1980

  • A Constitutive Equation for Nonlinear Stress Strain Curves in Rocks and Its Application to Stress Analysis Around a Borehole During Drilling

    SPE9328, SPE Annual Technical Conference and Exhibition    1980

  • Three Dimensional Permeability Measurements

    Proceedings of the 1980 SPE Annual Technical Conference and Exhibition, SPE9377    1980

  • Relative Permeability Measurements of Rocks from the Texas Gulf Coast Geopressured-Geothermal Reservoir at Low Free Gas Saturations

    Transactions of the Geothermal Resources Council.   4/,369-372  1980

  • Compaction of Sands and Shales of Geopressured Zones

    Proceedings of the International Conference on Geo-technical and Environmental Aspects of Geopressure Energy   /,93-107  1980

  • A Constitutive Equation for Nonlinear Stress Strain Curves in Rocks and Its Application to Stress Analysis Around a Borehole During Drilling

    SPE9328, SPE Annual Technical Conference and Exhibition    1980

  • Regression Analysis and Error Evaluation of Parameter Determination in Petroleum Engineering Problems. (3rd Report)-Some Considerations on Regression Analysis

    Jour. of the Japanese Association of Petroleum Technologists   44/2,18-25  1979

  • Regression Analysis and Error Evaluation of Parameter Determination in Petroleum Engineering Problems. (2nd Report)-Application of the Error Sensitivity Analysis to an Actual Petroleum Engineering Problem

    Jour. of the Japanese Association of Petroleum Technologists   44/2,10-17  1979

  • Regression Analysis and Error Evaluation of Parameter Determination in Petroleum Engineering Problems. (1st Report)-Error Sensitivity Analysis for Search Parameters and Predicted Performance

    Jour. of the Japanese Association of Petroleum Technologists   44/1,15-20  1979

  • The Deformation Behavior of Rocks from the Pleasant Bayou Wells

    Proceedings of the Forth U. S. Gulf Coast Geopressured Geothermal Energy Conference   /,1031-1059  1979

  • Stress Analysis for a Nonlinear Rock Structure by the Finite Element Method

    Jour. of The Japanese Association of Petroleum Technologists   44/1,21-29  1979

  • Regression Analysis and Error Evaluation of Parameter Determination in Petroleum Engineering Problems. (3rd Report)-Some Considerations on Regression Analysis

    Jour. of the Japanese Association of Petroleum Technologists   44/2,18-25  1979

  • Regression Analysis and Error Evaluation of Parameter Determination in Petroleum Engineering Problems. (2nd Report)-Application of the Error Sensitivity Analysis to an Actual Petroleum Engineering Problem

    Jour. of the Japanese Association of Petroleum Technologists   44/2,10-17  1979

  • Regression Analysis and Error Evaluation of Parameter Determination in Petroleum Engineering Problems. (1st Report)-Error Sensitivity Analysis for Search Parameters and Predicted Performance

    Jour. of the Japanese Association of Petroleum Technologists   44/1,15-20  1979

  • The Deformation Behavior of Rocks from the Pleasant Bayou Wells

    Proceedings of the Forth U. S. Gulf Coast Geopressured Geothermal Energy Conference   /,1031-1059  1979

  • Stress Analysis for a Nonlinear Rock Structure by the Finite Element Method

    Jour. of The Japanese Association of Petroleum Technologists   44/1,21-29  1979

  • Borchole Breakdown Pressure with Drilling Fluids : Part 2 Semi-analutical Solution to predict Borchole Breakdown Pressure

    Int.Journal of Rock Mech Min.Sci.& Geomech.Abst.1996   /,

    DOI

  • Borchole Breakdown Pressure with Drilling Fluids : Part 2 Semi-analutical Solution to predict Borchole Breakdown Pressure

    Int.Journal of Rock Mech Min.Sci.& Geomech.Abst.1996   /,

    DOI

▼display all

 

Internal Special Research Projects

  • 水平フランクチャーを利用した広域加熱法によるメタンハイドレート貯留層開発経済検討

    2005  

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    現在メタンハイドレート層の生産法には、安全であるが生産性が極度に悪い減圧法と、経済的生産性は見込めるが気化したガスの移動により地盤の不安定化をもたらす可能性のある加熱法が主流である。従来の加熱法の欠点は熱効率を高めるためハイドレート層に直接熱水・蒸気を圧入するものであった。しかし従来の方法では局所的にハイドレートをガス化し地層の不安定化を招き、またハイドレート層が水没する生産障害を引き起こす。ガス層に水が過剰に注入されると貯留層内のガスに対する相対浸透率が低下するという障害のほか坑井にかなりの水頭圧がかかり水をくみ上げる速度に限界があるためガス生産量が極度に低下する。ハイドレート層に対する圧入井は流体を圧入するのではなくハイドレートを分解するに要する熱量を供給することにある。岩石は熱に対して絶縁体であるが、広域な表面から熱を送れば、移流による熱供給なしで拡散のみによる熱供給が可能となる。この研究では加熱法に安全性をもたせた意図的に目詰まりさせた水平フラクチャーを利用する広域加熱法技術の(1)モデルスタディ、(2)経済検討、を行った。この研究では泥水を使用したフラクチャーの挙動解析、生産量が一坑井あたり1mmscf/day程度のメタンハイドレートの大まかな経済解析、また現実的に一坑井あたり1mmscf/day程度が生産可能かの、ハイドレート貯留層モデルの開発を行った。結果としてモデルスタディは進行中であるが経済検討は非常によくできているので今年度の石油技術協会で発表の予定である。

  • ニュートラルネットワークによる坑井安定解析手法の開発

    2002  

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    アラビア石油から岩石サンプルをもらい170サンプルに対して一軸圧縮試験を行い強度測定を行った。アラビア石油カフジ油田のロッギングを全てディジタイズして、ニューラルネットワークでロッギングデータを使い一軸圧縮試験強度を学習させた。学習結果の誤差は小さく実用に十分使用可能であることが判明した。またニューラルネットワークを使用し坑内破壊の程度をロッギングデータに関連付け学習を行った。このデータに関しても学習精度がよく、ロッギングによる坑内破壊の予測という実用用途に十分であることが判明した。結果は次の講演で発表される。森田信男、吉岡慶太講演: ニューラルネットワークによる岩石強度の予測、2003年度石油技術協会春季講演会

  • 超深度坑井周辺の岩石破壊実験

    2000  

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     大型3軸圧縮測定装置を使用して火山岩、石灰岩に対して14個の坑井破壊テストを行った。地下20㎞以上の超深度の条件での破壊実験に成功した。火山岩に対しては一軸試験で20-30Kpsiの強度の岩石でも坑内周辺にBreak-outが観察された。酸処理をおこなった石灰岩では酸処理前と酸処理以後では強度はほとんど同じであることが確認された。これらの結果はフィールドでの観察といっちしている。2人の卒業論文、2人の修士論文に結果が報告された。またそのソフトは出砂問題にも応用されフィールドスタディにも使用された。結果は学会で報告されたが今年度中に学会誌に発表する準備を行っている。

  • 坑井破壊に対するサイズ効果の測定

    1998  

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    大型3軸圧縮測定装置の坑内歪み測定器の開発と其のデータをコンピュータで収集する回路を3人の4年生に卒論として行わせた。測定ノイズの消去に非常に苦労していたが、2月になってその部分が完成し、アルミサンプルを使用してキャリブレーションを行った結果、ノイズは完全には消去されていないが実測定には支障ないところまでにいたっている。これから口径の異なる岩石で実際の破壊テストを行う予定である。一方数値モデルの開発は3次元坑井モデルを3人の4年生に卒論として行わせたが、いずれも弾性モデルの開発は境界要素法を使用して完成し、解析解とのクロスチェックの結果精度も10**(―5)程度で非常に良い精度のモデルが開発された。これらのモデルは3人の卒業論文としてまとめられた。これらのモデルをベースとして(1)非線型性、(2)フラクチャーの発達モデルといった岩石の非線型破壊を取り入れた実用モデルに変換される。一方実用的応用としてベースになるモデルをフィールド解析に使用し米国の石油学会に論文として発表されまた学生の論文として5月26―28日に行われる日本の石油学会でモデル結果が発表される。

  • 坑井破壊に対するサイズ効果の測定

    1997  

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    大型3軸圧縮測定装置で測定されたカースルゲート砂岩を使った8つの坑井安定テストの解析を行った。坑井径が比較的小さい(1.5―2.5インチ)サンプルでも、Drucker-Pragerの破壊理論と、Mohr-Coulombの破壊理論の中間で坑井破壊が生じることが確認された。しかし坑井は破壊をおこしても閉塞することなく開いていたため、堀削にはそれほど障害にならないことが確認された。坑井破壊を解析する有限要素法ソフトがいくつか作られ、3人の修士論文と4人の卒論に使用された。またそのソフトは出砂問題にも応用されフィールドスタデイにも使用された。しかしこの種の問題としては実験結果の解析に使用されるサンプル数があまりにも少なく(最低100の実験が必要)実フィールドに使われる理論としては未だ未完である。研究成果の発表1998年2月18日米国石油学会 Proceedings of International Formation Damage Control“Guideline for solving sand problems in water injection wells”1998年6月3日日本石油学会 平成10年度日本石油技術協会講演会要旨集“坑井周辺構造問題に対する有限要素法PCプログラム応用の限界”