Origin and Prediction of Abnormal Formation Pressures

Erscheinungsjahr 2002
ISBN: 978-0-444-51001-3
Verlag: Elsevier Science & Technology

Buch, Englisch, 390 Seiten

Reihe: Developments in Petroleum Science

Knowledge of the presence of abnormally-high pressure zones (AHFP) prior to drilling into them can prevent considerable economic losses and, possibly, save human lives. The various origins (undercompaction, tectonics, etc.) of AHFPs are discussed, followed by the description of predictive techniques in clastic, carbonate and salt-bearing formations. In addition to the well-logging predictive techniques, the authors discuss smectite-illite transformation and the chemistry of interstitial solutions. Other topics covered include (a) abnormally low formation pressures and subsidence, and (b) mathematical modelling. Loss of potential production may result if AHFPs are not properly identified and evaluated. Many hydrocarbon-bearing formations with AHFPs are erroneously "condemned".
This book is of interest to engineers and geologists involved in the (a) evaluation, (b) drilling in, (c) completing, and (d) producing from hydrocarbon reservoirs with AHFPs.

Autoren/Hrsg.

Chilingar, G.V.

Serebryakov, V. A.

Robertson, J. O.

Fachgebiete

• Technische Wissenschaften Energietechnik | Elektrotechnik Erdölenergietechnik

Inhaltsverzeichnis

Preface. List of Contributors. 1. Introduction to Abnormally Pressured Formations. (E.C. Donaldson 'et al'.). Introduction. Abnormal pressures. Subpressures. Surpressures. Origin of vertical barriers resulting in abnormal formation pressures. Undercompaction. Tectonic compression. Faulting. Diapirism. Geothermal temperature. Phase changes that produce abnormal pressures. Osmosis as a factor for generation of abnormal pressure. Salinity of interstitial water. Reservoir engineering concepts in abnormal pressure environments 13
Economics in overpressure environments. Summary. Bibliography. 2. Origin of Abnormal Formation Pressures (G.V. Chilingar 'et. al.'). Introduction. Definitions. Compaction process. Hydrostatic pressure. Formation or interstitial fluid pressure.
Sediment consolidation. State of stress in compacting shales. Resolution of the total stress field. Hydrostatic stress state. Deviatoric stress state. Total stress tensor. Spring models of compaction. Hooke's law. Load transfer. Porosity-density variations with depth. Compaction models. Athy's compaction model. Hedberg's compaction model. Weller's compaction model. Powers' compaction model. Teodorovich and Chernov's compaction model. Burst's compaction model. Beall's compaction model. Overton and Zanier's compaction model. Creation and maintenance of abnormal pressures. Mechanisms generating abnormal formation pressures. Undercompaction. Tectonics. Growth faults. Transference. Effect of temperature increase on formation pressure (aquathermal pressuring). Decomposition of organic matter. Gas migration. Osmosis. Density contrast. Conclusions. Bibliography. 3. Origin of Formation Fluid Pressure Distributions (A. Gurevich 'et al.'). Introduction. Factors causing fluid flow and pressure distributions. Factors of fluid flow and pressure distribution and changes. Free convection of ground fluids. Forced convection of ground fluids. Role and distribution of formation permeability. Presentation of pressure as the additive sum of two components. Some major factors of underground fluid forced convection and characteristics for correlation. Compaction of granular sediments. Upward fluid migration. Correlation between porosity and pressure. Methods used in Azerbaijan to determine abnormal pressures. Distributions of abnormal pressures. Definitions of terms as used in this chapter. Conclusions. Bibliography. 4. Smectite-Illite Transformations during Diagenesis and Catagenesis as Related to Overpressures (L.A. Buryakovsky 'et al.'). Introduction. Burst's compaction model. Origin of abnormally high formation pressure. Clay-mineral transformation. Effect of thermobaric conditions. Effect of hydrochemical factors. Discussion. Summary. Conclusions. Bibliography. 5. Methods of Estimating and Predicting Abnormal Formation Pressures
(G.V. Chilingar 'et al.'). Introduction. Prediction of abnormally high pressure in regions with nonequilibrium compaction. Abnormal pressure due to temperature variations. Estimation and prediction of abnormally low pressures in basins in permafrost regions. Formation pressure in regions with upthrown and downthrown blocks (uplift and subsidence of sedimentary rocks). Calculation of abnormal pore pressure during drilling. Method of equivalent depth. Method of normal compaction trend. Method of compressional curves. Radioactivity study of zones with abnormally high formation pressure. Pulsed neutron capture logs. Quantitative pressure evaluation. Technique A: empirical calibration charts. Method B: equivalent depth method. Shalewater influx - driving mechanism. Various geophysical well logging methods - a summary. Conclusions. Bibliography. 6. Drilling Parameters (W.H. Fertl 'et al.'). Drilling rate (penetration). Normalized rate of penetration (d-exponent). Effect of drilling hydraulics. Effect of drill bits. Overbalance. Drilling rate equations. Porosity and formation pressure logs. Logging while drilling. Torque. Drag. Drilling mud parameters. Mud-gas