Atlas of Typical Seismic and Geological Sections for Major Petroliferous Basins in China [1st ed.] 9789811567902, 9789811567919

Table of contents :
Front Matter ....Pages i-viii
Structural Style and Seismic Profile Characteristics (Shouli Qu)....Pages 1-41
Sedimentary Sequence and Seismic Response (Shouli Qu)....Pages 43-58
Seismic Response Characteristics of Typical Geologic Bodies (Shouli Qu)....Pages 59-86
Seismic Geological Characteristics of Typical Oil and Gas Reservoirs (Shouli Qu)....Pages 87-98
Back Matter ....Pages 99-99

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SPRINGER BRIEFS IN EARTH SCIENCES

Shouli Qu

Atlas of Typical Seismic and Geological Sections for Major Petroliferous Basins in China 石油工业出版社有限公司 PETROLEUM

INDUSTRY

PRESS

123

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Shouli Qu

Atlas of Typical Seismic and Geological Sections for Major Petroliferous Basins in China

123

Shouli Qu SinoPec Petroleum Exploration and Production Research Institute Beijing, China

ISSN 2191-5369 ISSN 2191-5377 (electronic) SpringerBriefs in Earth Sciences ISBN 978-981-15-6790-2 ISBN 978-981-15-6791-9 (eBook) https://doi.org/10.1007/978-981-15-6791-9 Jointly published with Petroleum Industry Press The print edition is not for sale in China (Mainland). Customers from China (Mainland) please order the print book from: Petroleum Industry Press. © Petroleum Industry Press 2021 This work is subject to copyright. All rights are reserved by the Publishers, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publishers, the authors, and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publishers nor the authors or the editors give a warranty, express or implied, with respect to the material contained herein or for any errors or omissions that may have been made. The publishers remain neutral with regard to jurisdictional claims in published maps and institutional affiliations. This Springer imprint is published by the registered company Springer Nature Singapore Pte Ltd. The registered company address is: 152 Beach Road, #21-01/04 Gateway East, Singapore 189721, Singapore

Foreword

In the past 20 years, Sinopec has made significant achievements in domestic oil and gas exploration. It has successively discovered a number of large oil and gas fields in the Tarim basin, Sichuan basin, and Ordos basin in western China. New oil and gas discoveries have also been made in new fields and strata in the old oil and gas regions of eastern China. Oil and gas exploration results have given us important enlightenment: The discovery of large oil and gas fields first depends on the innovation of geological ideas and knowledge, and secondly, the advancement of geophysical technology and improvement of the quality of seismic data. Within 20 years, most oil and gas fields have implemented three-dimensional seismic exploration. At the same time, new processing and interpretation technologies based on big data and cloud computing have been applied. This greatly improved the quality of seismic data and digged out more attributes and information for explorationist to identify, predict, and describe underground oil and gas reservoirs, thereby promoting the closer integration of seismic and geology technology. Typical geological bodies and reservoirs have typical seismic response characteristics, which deserve to be summarized carefully. I’m glad to see the “Atlas of typical seismic and geological sections for major petroliferous basins in China” to meet with readers. This book summarizes the seismic geological characteristics of typical sedimentary, structure, and reservoir of major petroliferous basins in China. It can not only help geophysical prospecting workers better recognize geological model, but can also allow geologists to understand the seismic response characteristics of geological bodies. It is an important reference book for oil and gas exploration workers to strengthen the close integration of seismic and geology technology. The author of this book, Prof. Shouli Qu, is a well-known geophysicist in China. He is a technical leader in the field of geophysical prospecting in China. He has profound knowledge in seismic exploration methods and applications, software development, and information construction. He led the team to finish the book in nearly two years. The book is well illustrated, which contains the exploration

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Foreword

experience accumulated by the author for many years, and also presents the progress of geophysical technology. I believe this book has important reference and guiding significance for geologists and geophysicists. Beijing, China

Yongsheng Ma

Contents

1 Structural Style and Seismic Profile Characteristics . . . . . . . . . 1.1 Extensional Structures and Seismic Profile Characteristics . . . 1.1.1 Normal Faults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.2 Extensional Structures . . . . . . . . . . . . . . . . . . . . . . . 1.2 Compressional Structures and Seismic Profile Characteristics 1.2.1 Folds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2.2 Reverse Fault . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2.3 Reverse Fault Related Folds . . . . . . . . . . . . . . . . . . . 1.2.4 Compressional Structures . . . . . . . . . . . . . . . . . . . . . 1.3 Torsional Structures and Seismic Profile Characteristics . . . . 1.3.1 Strike-Slip Fault . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3.2 Flower Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4 Vertical Structures and Seismic Profile Characteristics . . . . . 1.4.1 Dissolution Collapse Back-Type Structure . . . . . . . . . 1.4.2 Diapir Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4.3 Drape Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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1 1 1 4 14 14 14 17 20 21 21 22 25 26 28 29 41

2 Sedimentary Sequence and Seismic Response . . . . . . . . . . . . . . 2.1 Seismic Reflection Characteristics of Sedimentary Sequence Boundary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1.1 Integration Surface . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1.2 Unconformity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 Stratigraphic Structure and Seismic Reflection Characteristics 2.2.1 The Configuration of Sedimentary Unit . . . . . . . . . . . 2.2.2 Internal Structure of Sedimentary Sequence . . . . . . . .

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3 Seismic Response Characteristics of Typical Geologic Bodies . . . . . . 3.1 Fans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2 Fluvial Sandbody . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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3.3 3.4 3.5 3.6 3.7 3.8

Delta Sandbody . . . . . . . . . . . . . . . . Marine Shore Sandbody . . . . . . . . . . Carbonate Fractured-Vuggy Reservoir Reef-Shoal Reservoir . . . . . . . . . . . . Intrusive Igneous Rock . . . . . . . . . . . Eruptive Igneous Rocks . . . . . . . . . .

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4 Seismic Geological Characteristics of Typical Oil and Gas Reservoirs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1 Carbonate Fracture-Cavern Reservoir—The S Reservoir . . . . . 4.2 Lithologic Gas Reservoirs in Fluvial Sand Bodies—D Oilfield 4.3 Volcanic Gas Reservoir—Y Gas Reservoir . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Appendix: Description of Color Bars in Seismic Profiles . . . . . . . . . . . . .

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Chapter 1

Structural Style and Seismic Profile Characteristics

This chapter presents the typical structural patterns and seismic profile characteristics of major petroliferous basins in China, including typical extensional structural patterns such as listric, rotary normal fault, flower structure, as well as large slip compression structures such as fault-propagation fold deformation and thrust (Fig. 1.1).

1.1 Extensional Structures and Seismic Profile Characteristics 1.1.1 Normal Faults (1) Straight normal fault The upper and footwall of the normal fault have only vertical displacement and no angular rotation. This is usually characterized in seismic profile as the fault or twist of the seismic reflection events, high and steep fault plane, and downward movement of the seismic events of upperside normal fault (Figs. 1.2, 1.3 and 1.4). (2) Listric normal fault Listric faults have concave fault plane, and the occurrence of the fault plane gradually slows down with increasing depth. The listric faults is usually the boundary fault of the dustpan-shaped fault sag basin, and the upperside rock layer rotates during the evolution process. These types of faults are generally large in scale and present fault steps at the edges of fault sags (Figs. 1.5, 1.6, 1.7 and 1.8).

© Petroleum Industry Press 2021 S. Qu, Atlas of Typical Seismic and Geological Sections for Major Petroliferous Basins in China, SpringerBriefs in Earth Sciences, https://doi.org/10.1007/978-981-15-6791-9_1

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1 Structural Style and Seismic Profile Characteristics

Fig. 1.1 Geological outcrop of box-shaped anticline structure in Tarim basin

Fig. 1.2 Geological model of straight normal fault

Fig. 1.3 Geological outcrop of straight normal fault

(3) Slope-type normal fault The main boundary fault on one side of the fault sag, the fault plane is formed by the steeper “fault ramp” and the gently dipping “fault flat". The upperside rock layer is prone to rotation and tilt; the slope-type fault composed of two fault ramps and one fault flat is also called chair-shaped fault (Figs. 1.9, 1.10 and 1.11).

1.1 Extensional Structures and Seismic Profile Characteristics

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Fig. 1.4 Seismic profile of straight normal fault normal fault

Listric fault

Fig. 1.5 Geological model of listric normal fault

Fig. 1.6 Seismic profile of listric normal fault in Bohai Bay Basin

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1 Structural Style and Seismic Profile Characteristics

Fig. 1.7 Seismic profile of listric normal fault in Songliao Basin

(4) Conjugate normal fault Conjugate normal fault is a common structure in tensional or torsional stress environment. It is a cross shear zone with different directions and opposite shear direction due to the difference of stress fields between deep and shallow parts (Figs. 1.12, 1.13 and 1.14).

1.1.2 Extensional Structures Extensional structure can be divided into cap and basement extensional structure. Cap extensional structures mainly include the associated structures of listric normal fault (reverse normal faults, rolling anticline) and diapiric extensional structures (arch wedge normal faults). Basement extensional structures mainly include extensional fault blocks (horst, graben) and basement detachment faults (Dai 2006). (1) Antithetic normal fault The reverse normal fault (domino fault system) is the main structural pattern of thinskinned caprock detachment and extension structure. It is identified on the seismic

1.1 Extensional Structures and Seismic Profile Characteristics

5

Fig. 1.8 Seismic profile of listric normal fault in Subei Basin

Fig. 1.9 Geological model of slope-type normal fault

profile by that the tendency of the fault plane is opposite to the occurrence of the two plates of strata (Figs. 1.15, 1.16 and 1.17). (2) Concordant normal fault The Concordant normal fault is also the main structural type of the thin-skinned caprock detachment and extension structure. It is identified on the seismic profile by that the fault plane tendency is consistent with the occurrence of the two plates of strata (Figs. 1.18, 1.19, 1.20, 1.21 and 1.22).

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1 Structural Style and Seismic Profile Characteristics

Fig. 1.10 Seismic profile of slope-type normal fault in Subei Basin

Fig. 1.11 Seismic profile of slope-type normal fault in Songliao Basin

(3) Drag folds Drag folds are usually confined to the vicinity of fault plane and are generally small in scale. The upperside usually presents an asymmetric syncline, with a steep flank near the fault and a slow flank near the depression. Anticlines are common in the footwall (Figs. 1.23 and 1.24).

1.1 Extensional Structures and Seismic Profile Characteristics

Fig. 1.12 Geological outcrop of conjugate normal fault

Fig. 1.13 Geological model of conjugate normal fault

Fig. 1.14 Seismic profile of conjugate normal fault in Jianghan Basin

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Fig. 1.15 Geological model and outcrop of antithetic normal fault

Fig. 1.16 Seismic profile of antithetic normal fault in Subei Basin

1.1 Extensional Structures and Seismic Profile Characteristics

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Fig. 1.17 Seismic profile of antithetic normal fault in Bohai Bay Basin

Fig. 1.18 Geological model of concordant normal fault

(4) Rolling anticline Rolling anticline, also known as reverse drag structure, refers to an upward curved anticline formed by the formation of the footwall due to the differential compaction or gravity of the two plates in the growth of the fault (Figs. 1.25 and 1.26). (5) Diapiric extensional structures The upper arch of magma, mudstone and gypsum rock causes the overlying strata to stretch and slide down, forming normal fault or collapse graben, and the reverse drag anticline and growth fault are common in extension structures related to diapiric structure (Figs. 1.27, 1.28, 1.29 and 1.30).

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1 Structural Style and Seismic Profile Characteristics

Fig. 1.19 Geological of concordant normal fault

Fig. 1.20 Seismic profile of concordant normal fault in Bohai Bay Basin

(6) Horst, Graben Horst: uplifted fault block clamped by two sets of normal faults with nearly parallel strike and opposite tendency is called graben. Graben: descended fault block clamped by two sets of normal faults with nearly parallel strike and tendency shifting toward each other is called graben, half-graben is also common (Figs. 1.31, 1.32, 1.33 and 1.34).

1.1 Extensional Structures and Seismic Profile Characteristics

Fig. 1.21 Seismic profile of concordant normal fault in Bohai Bay Basin

Fig. 1.22 Seismic profile of concordant step normal fault in Songliao Bay Basin

Fig. 1.23 Geological model of drag fold

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1 Structural Style and Seismic Profile Characteristics

Fig. 1.24 Seismic profile of concordant step normal fault in Bohai Bay Basin

Fig. 1.25 Geological model of rolling anticline

(7) Inversion structure Inversion structure is a special superimposed structure. The early tensional or tensional-torsional faults are called positive inversion structure when they are transformed into compressive or compressional-torsional faults in the later stage; the early compression system is called negative inversion structure when it is partially transformed into normal fault (Fig. 1.35, 1.36, 1.37 and 1.38).

1.1 Extensional Structures and Seismic Profile Characteristics

Fig. 1.26 Seismic profile of rolling anticline in Dongpu sag

Fig. 1.27 Geological model of diapiric extensional structures

Fig. 1.28 Seismic profile of mudstone diapiric extensional structures

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Fig. 1.29 Seismic profile of volcanite diapiric extensional structure in Tarim Basin

1.2 Compressional Structures and Seismic Profile Characteristics 1.2.1 Folds The compressional structure is mainly distributed in the flexural or contractional basin in the front of the orogenic belt. Thrust fold structures often occur along the front of orogenic belts. In this section the basic elements of compressional structure, such as reverse fault and related fold were first introduced; then, the main types of compressional structures and typical seismic profiles were presented (Figs. 1.39, 1.40, 1.41, 1.42, 1.43, 1.44 and 1.45).

1.2.2 Reverse Fault The reverse fault is mainly formed by horizontal compression and gravity, which are manifested by that the upperside wall rises and the footwall falls (Figs. 1.46, 1.47 and 1.48).

1.2 Compressional Structures and Seismic Profile Characteristics

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Fig. 1.30 Seismic profile of volcanite diapiric extensional structure in Songliao Bay Basin

Fig. 1.31 The basic structural patterns of extensional fault sag basin on seismic profile a horst and graben; b domino half-horst; c wave half-horst; d complex half-horst

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1 Structural Style and Seismic Profile Characteristics

Fig. 1.32 Seismic profile of buried-hill horst and graben in Chengdao area in Bohai Bay Basin

Fig. 1.33 Seismic profile of horst and graben in the Ordos Basin

Fig. 1.34 Seismic profile of half-horst in Songliao Basin

1.2 Compressional Structures and Seismic Profile Characteristics

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Fig. 1.35 Geological model of positive inversion structure

Fig. 1.36 Seismic profile of positive inversion structure in Tarim Basin

Fig. 1.37 Seismic profile of positive inversion structure in Songliao Basin

1.2.3 Reverse Fault Related Folds According to the relationship between fold and fault in thrust-nappe belt, folds can be divided into three types: fault-bend fold (fault bending fold), fault-propagation fold (fault extension fold), and detachment fold (fault detachment fold). (1) Fault-bend fold See Figs. 1.49 and 1.50.

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1 Structural Style and Seismic Profile Characteristics

Fig. 1.38 Seismic profile of positive inversion structure in the Ordos Basin

Fig. 1.39 Geological outcrop of anticline and syncline folds

1.2 Compressional Structures and Seismic Profile Characteristics

Fig. 1.40 Geological profile of anticline and syncline

Fig. 1.41 Seismic profile of anticline and syncline folds in large scale in Sichuan Basin

Fig. 1.42 Seismic profile of Sichuan anticline folds in large scale

(2) Fault-propagation fold See Figs. 1.51, 1.52 and 1.53. (3) Detachment fold See Figs. 1.54 and 1.55.

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1 Structural Style and Seismic Profile Characteristics

Fig. 1.43 Three-dimension display of anticline folds in large scale

Fig. 1.44 Seismic time-slice map of anticline folds in large scale

(4) Composite reverse fault folds See Figs. 1.56, 1.57, 1.58 and 1.59.

1.2.4 Compressional Structures (1) Pop-up structure According to the arrangement of thrust faults, they can be divided into back thrust type, ramp type, wedge thrust type and other compressional structural styles. Nappe structure is usually composed of a set of faults with similar occurrence and thrusting in one direction, which is characterized by imbricate structure style (Figs. 1.60, 1.61, 1.62, 1.63 and 1.64).

1.2 Compressional Structures and Seismic Profile Characteristics

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Fig. 1.45 Seismic profile of wide-gentle box-shaped anticline structure in Sichuan basin

(2) Ramp structure See Figs. 1.65, 1.66 and 1.67. (3) Thrust-Nappe structure See Figs. 1.68, 1.69, 1.70 and 1.71.

1.3 Torsional Structures and Seismic Profile Characteristics Wrench structure is a structural system formed by relative torsion of a part of the earth’s crust to its adjacent parts. On the profile of wrench fault, the main fault plane is nearly vertically inserted into the basement, and it spreads upward and outwards with flower like characteristics. On the plane, the two sides of the fault slide horizontally with each other, the simultaneous faults or folds are distributed in echelon (Fig. 1.72).

1.3.1 Strike-Slip Fault See Figs. 1.73, 1.74, 1.75, 1.76, 1.77, 1.78, 1.79, 1.80 and 1.81.

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1 Structural Style and Seismic Profile Characteristics

Fig. 1.46 2 geological model of reverse fault (a, b)

1.3.2 Flower Structure The flower structure is formed by a torsion action, with faults inserted steeply into the basement and spreading upwards and outwards. The strike-slip faults can be divided into positive and negative flower structure due to their different tendency components (Figs. 1.82, 1.83, 1.84, 1.85, 1.86, 1.87, 1.88 and 1.89).

1.3 Torsional Structures and Seismic Profile Characteristics

Fig. 1.47 Seismic profile of high and steep thrust fault in northern ordos basin

Fig. 1.48 Seismic profile of basement-involved overthrust

Fig. 1.49 Geological model of fault-bend fold

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Fig. 1.50 Seismic profile of fault-bend fold in the Ordos Basin

Fig. 1.51 Geological model of fault-propagation fold

Fig. 1.52 Seismic profile of fault-propagation fold in Tarim Basin

1.4 Vertical Structures and Seismic Profile Characteristics

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Fig. 1.53 Seismic profile of fault-propagation fold in Sichuan Basin

Fig. 1.54 Geological model of detachment fold

Fig. 1.55 Seismic profile of detachment fold in Tarim Basin

1.4 Vertical Structures and Seismic Profile Characteristics The vertical structure refers to the deformation under the action of vertical structural movement. It mainly includes the dissolution collapse back-type structure, diapir structure, compaction structure, drape structure, buried-hill structure and so on.

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1 Structural Style and Seismic Profile Characteristics

Fig. 1.56 Diagram of ejective folds

Fig. 1.57 Seismic profile of ejective folds in Sichuan Basin

Fig. 1.58 Seismic profile of trough-like fold in Sichuan Basin

1.4.1 Dissolution Collapse Back-Type Structure See Figs. 1.90 and 1.91.

1.4 Vertical Structures and Seismic Profile Characteristics

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Fig. 1.59 Seismic profile of reverse detachment fault-propagation fold in northeast of Sichuan Basin (the detachment layer is soft gypsum and shale)

Fig. 1.60 Geological model of pop-up and ramp structures

Fig. 1.61 Geological model of pop-up structures

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1 Structural Style and Seismic Profile Characteristics

Fig. 1.62 Seismic profile of pop-up in Turpan-Hami Basin

Fig. 1.63 Seismic profile of pop-up in north of the Ordos Basin

Fig. 1.64 Seismic profile of pop-up in the Tarim Basin

1.4.2 Diapir Structure See Figs. 1.92, 1.93, 1.94, 1.95 and 1.96.

1.4 Vertical Structures and Seismic Profile Characteristics

Fig. 1.65 Geological model of ramp structure

Fig. 1.66 Seismic profile of ramp structure in the Ordos Basin

1.4.3 Drape Structure See Figs. 1.97, 1.98 and 1.99.

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Fig. 1.67 Seismic profile of ramp structure in Sichuan Basin

Fig. 1.68 Schematic diagram of two typical thrust nappe structures

Fig. 1.69 Seismic profile of imbricate thrust in the western edge of the Ordos Basin

Fig. 1.70 Seismic profile of thrust imbricate structure in the Sichuan Basin

1.4 Vertical Structures and Seismic Profile Characteristics

Fig. 1.71 Seismic profile of thrust imbricate structure in the Tarim Basin

Fig. 1.72 Aerial photos of strike-slip faults in the east of Tianshan Mountain

Fig. 1.73 Geological model of strike-slip faults

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Fig. 1.74 Seismic profile of strike-slip faults in the Tarim Basin

Fig. 1.75 Seismic profile of strike-slip faults in the Tarim Basin

Fig. 1.76 Plane graph of curvature attribute along the layer (the fracture is distributed in the shape of broom or feather)

1.4 Vertical Structures and Seismic Profile Characteristics

Fig. 1.77 Seismic profile of strike-slip faults in the Tarim Basin

Fig. 1.78 Plane graph of seismic coherent attribute along the layer

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Fig. 1.79 Three dimensional spatial distribution of fracture surface of strike-slip fault

Fig. 1.80 Seismic profile of strike-slip fault in the Bohai Bay Basin

Fig. 1.81 Seismic profile of strike-slip fault in the Bohai Bay Basin

1.4 Vertical Structures and Seismic Profile Characteristics

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Fig. 1.82 Schematic diagram of flower structure (left: positive flower; middle: negative flower; right: flower structure with mirror surface)

Fig. 1.83 Complex or incomplete flower structures are common

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1 Structural Style and Seismic Profile Characteristics

Fig. 1.84 Seismic profile of negative flower structure in the Songliao Basin

Fig. 1.85 Plane graph of seismic coherent attribute

Fig. 1.86 Seismic profile and seismic coherent attribute of negative flower structure in the Songliao Basin

1.4 Vertical Structures and Seismic Profile Characteristics

Fig. 1.87 Plane graph of seismic coherent attribute

Fig. 1.88 Seismic profile of negative flower structure in the Songliao Basin

Fig. 1.89 Seismic profile of negative flower structure in Guangxi

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Fig. 1.90 Geological model and outcrop of cave and collapse

Fig. 1.91 Seismic profile of typical karstic cave in the Tarim Basin

Fig. 1.92 Diagram of diapir structure

1.4 Vertical Structures and Seismic Profile Characteristics

Fig. 1.93 Seismic profile of volcanic diapir structure in the Tarim Basin

Fig. 1.94 Seismic profile of diapir structure of igneous rock in the Songliao Basin

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Fig. 1.95 Seismic profile of diapir structure of igneous rock in the Bohai Bay Basin

Fig. 1.96 Seismic profile of diapir structure of gypsum rock in the Tarim Basin

1.4 Vertical Structures and Seismic Profile Characteristics

Fig. 1.97 Geological model of typical buried-hill drape structure

Fig. 1.98 Seismic profile of buried-hill drape structure in the Bohai Bay Basin

Fig. 1.99 Seismic profile of basement paleo-uplift drape structure in the Ordos Basin

Reference Dai J (2006) Structural geology and geotectonics. Petroleum Industry Press

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Chapter 2

Sedimentary Sequence and Seismic Response

Sedimentary sequence is a stratigraphic unit, which is composed of relatively uniform and genetically related strata. On the seismic profile, the boundary of the sedimentary sequence can be identified by the lateral disappearance of strata such as the onlap, downlap, toplap and truncation. This chapter mainly illustrates the seismic reflection characteristics of the sedimentary sequence boundary and the stratigraphic structure within a sedimentary sequence on the seismic profile (Fig. 2.1).

2.1 Seismic Reflection Characteristics of Sedimentary Sequence Boundary 2.1.1 Integration Surface It is an integrated contact relationship between a set of continuously deposited strata. The seismic response characteristics of the integrated surface generally show parallel and subparallel seismic reflection waveforms (Figs. 2.2 and 2.3).

2.1.2 Unconformity The unconformity surface is an eroded or non-sedimentary surface, which not only separates the old and new strata, but also represents obvious sedimentary discontinuities. The unconformity phenomenon is the main criterion used to determine the boundary of the sedimentary sequence. The relationship between the stratum and the sedimentary sequence boundary mainly includes truncation, toplap and baselap.

© Petroleum Industry Press 2021 S. Qu, Atlas of Typical Seismic and Geological Sections for Major Petroliferous Basins in China, SpringerBriefs in Earth Sciences, https://doi.org/10.1007/978-981-15-6791-9_2

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Fig. 2.1 Geological outcrop photos of Neogene in Inner Mongolia

Fig. 2.2 Geological model diagram of integrated contact relationship

(1) Trunction See Figs 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 2.10 and 2.11. (2) Toplap See Figs. 2.12 and 2.13. (3) Baselap See Figs. 2.14, 2.15 and 2.16.

2.1 Seismic Reflection Characteristics of Sedimentary Sequence Boundary

Fig. 2.3 Seismic profile with integrated contact relationship in Tarim Basin

Fig. 2.4 Geological model diagram of truncation contact relationship

Fig. 2.5 Geological photo of truncation contact relationship

(4) Downlap See Figs. 2.17 and 2.18.

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Fig. 2.6 Seismic profile with truncation contact relationship in Tarim Basin

Fig. 2.7 Three seismic profiles with typical strata truncation

2.2 Stratigraphic Structure and Seismic Reflection Characteristics Within a sedimentary sequence, the stratigraphic structure mainly includes the shape of the sedimentary sequence unit and the stacking types of the strata, such as retrogradational type and progradational type. For stable sedimentary sequence with horizontally uniform distribution, the seismic profile shows a set of relatively uniform parallel reflections of seismic

2.2 Stratigraphic Structure and Seismic Reflection Characteristics

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Fig. 2.8 Top truncation of Jurassic in Tuha Basin

Fig. 2.9 Instantaneous phase profile

Fig. 2.10 Flatten the unconformity surface for adjacent marker reflection horizon, the truncation point is more clear

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Fig. 2.11 Peak amplitude attribute plane map extracted along the truncation section (Sometimes strong and weak amplitudes appear alternately, spread in parallel stripes on the plane)

Fig. 2.12 Geological model diagram of toplap

Fig. 2.13 Seismic profile of top surface toplap of delta foreset

waveform. When the shape of sedimentary body and the stratum structure change, the seismic waveform shows significant changes in attribute parameters including continuity, inclination, amplitude, frequency and so on. These changes can help geophysicists determine sedimentary environments and predict lithology or facies.

2.2 Stratigraphic Structure and Seismic Reflection Characteristics

Fig. 2.14 Geological model diagram of baselap contact relationship

Fig. 2.15 Seismic profile of stratigraphic baselap in Tarim Basin

Fig. 2.16 Seismic profile of Stratigraphic onlap in Songliao Basin

Fig. 2.17 Schematic diagram of downlap contact relationship

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Fig. 2.18 Typical seismic profile of downlap reflection characteristics in Tarim Basin

2.2.1 The Configuration of Sedimentary Unit The shape of sedimentary unit is generally divided into mat shape, wedge shape, lens shape, mound shape, filling, etc. (1) Mat shape See Figs. 2.19 and 2.20. (2) Wedge shape See Figs. 2.21, 2.22 and 2.23 (3) Lens shape See Figs. 2.24, 2.25 and 2.26. (4) Filling See Figs. 2.27, 2.28 and 2.29

Fig. 2.19 Seismic profile with mat-shaped stratum structure in Sichuan Basin

2.2 Stratigraphic Structure and Seismic Reflection Characteristics

Fig. 2.20 Seismic profile with mat-shaped stratum structure in Tarim Basin

Fig. 2.21 Schematic diagram of wedge geological model

Fig. 2.22 Seismic profile of wedge-shaped geological body in Songliao Basin

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Fig. 2.23 Seismic profile of wedge-shaped geological body in Bohai Bay Basin

Fig. 2.24 Schematic diagram of sandstone lens

Fig. 2.25 Sandstone lens in Yuanba area, Sichuan Basin

2.2 Stratigraphic Structure and Seismic Reflection Characteristics

Fig. 2.26 Characteristics of short-event strong amplitude seismic reflection of sandstone lens

Fig. 2.27 Diagram of filling structure

Fig. 2.28 Seismic profile of crater filling characteristics in Tazhong area, Tarim Basin

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Fig. 2.29 Seismic profile with filling characteristics in southern Ordos Basin Basin

(5) Mound shape See Figs. 2.30, 2.31, 2.32 and 2.33.

Fig. 2.30 Mound seismic reflection characteristics of biological reef in Sichuan Basin

Fig. 2.31 Mound seismic reflection characteristics of biological reef in Tarim Basin

2.2 Stratigraphic Structure and Seismic Reflection Characteristics

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Fig. 2.32 Mound seismic reflection characteristics of gypsum-salt rock in Sichuan Basin

Fig. 2.33 Mound seismic reflection characteristics in southern Ordos basin

2.2.2 Internal Structure of Sedimentary Sequence The stratigraphic structure within a sedimentary sequence is mainly parallel, subparallel, divergent, foreset, chaotic and so on. Two main structures of foreset and chaotic are mainly illustrated here. (1) Foreset See Figs. 2.34, 2.35, 2.36, 2.37 and 2.38. (2) Chaotic See Figs. 2.39, 2.40 and 2.41.

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Fig. 2.34 Seismic reflection characteristics of S-shaped foreset structure in Sichuan Basin

Fig. 2.35 Seismic reflection characteristics of foreset structure in Tarim Basin

Fig. 2.36 Seismic reflection characteristics of oblique foreset structure

2.2 Stratigraphic Structure and Seismic Reflection Characteristics

Fig. 2.37 Seismic reflection characteristics of S-shaped foreset structure in Sichuan Basin

Fig. 2.38 Seismic reflection characteristics of foreset structure in Tarim Basin

Fig. 2.39 Chaotic seismic reflection characteristics inside ancient bedrock

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Fig. 2.40 Chaotic seismic reflection characteristics in eruptive facies of volcanic rocks

Fig. 2.41 Chaotic seismic reflection characteristics of high and steep structure position

Chapter 3

Seismic Response Characteristics of Typical Geologic Bodies

Oil and gas exploration is mainly concentrated in the three major areas of clastic rocks, carbonate rocks and igneous rocks. This chapter mainly illustrates the geological models, typical seismic profiles and plane attribute maps of fans, fluvial facies sand bodies, delta underwater distributary channel sand bodies, beach bar sand bodies, carbonate fracture caves, biological reef-beach bodies and igneous rocks (Fig. 3.1).

3.1 Fans Regardless of whether it is a turbidite fan, an offshore fan, or a mountain front alluvial fan, on the seismic profile, the fan body usually displays geometric shapes such as lenticular and wedge shape, and the interior structure is usually convergent or divergent, layered, messy, imbricate, etc. Medium and strong amplitude reflections appear at the top and bottom of the fan body; and the fan body is generally planar and distributed in a ring shape along the shoreline of the lake (Figs. 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9 and 3.10).

3.2 Fluvial Sandbody See Figs. 3.11, 3.12, 3.13, 3.14, 3.15 and 3.16.

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Fig. 3.1 Schematic diagram of clastic rock deposition

Fig. 3.2 Alluvial fan in front of the mountain

Fig. 3.3 Debris flow accumulation in fan root subfacies in alluvial fans, and outcrops of middle-fan and ending-fan

3.3 Delta Sandbody

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Fig. 3.4 Seismic profile of turbidite fan in Bohai Bay Basin

Fig. 3.5 Seismic Profile of Plane distribution of deep water turbidite fans in Bohai Bay Basin

Fig. 3.6 Seismic profile of deepwater turbidite fan in Bohai Bay Basin

3.3 Delta Sandbody The deltas can be divided into two types: Lacustrine and Marine deltas, both of which are characterized by three layers: top layer, foreset layer and bottom layer.

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Fig. 3.7 Seismic profile of underwater fan in Bohai Bay Basin

Fig. 3.8 Seismic profile of multi-stage offshore fan in Subei Basin

The lacustrine and Marine deltas are cyclically controlled by factors such as sea level rise and fall, so we often see some deltaic complexes. The different types and shapes of rocks deposited by different subfacies and microfacies in the Delta can cause the difference of seismic response, which is the theoretical basis for us to identify favorable reservoirs in the delta by seismic response characteristics (Figs. 3.17, 3.18, 3.19, 3.20, 3.21, 3.22, 3.23, 3.24, 3.25, 3.26 and 3.27).

3.4 Marine Shore Sandbody

Fig. 3.9 Seismic profile of alluvial fan in Bohai Bay Basin

Fig. 3.10 Plane distribution of deep water turbidite fans in Bohai Bay Basin

Fig. 3.11 Fluvial Facies Conglomerate layer

3.4 Marine Shore Sandbody See Figs. 3.28, 3.29 and 3.30.

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Fig. 3.12 Seismic profile characteristics of the delta plain sand bodies in Junggar Basin

Fig. 3.13 Seismic profile characteristics of braided river sediments in Junggar Basin

3.5 Carbonate Fractured-Vuggy Reservoir Carbonate rocks may undergo large-scale karst transformation to form large-scale ancient karst landforms and develop large-scale fracture-cave reservoirs; or undergo dolomite formation and weak karst transformation to form Porous reservoir and pore-seam reservoirs; or undergo Stress transformation to form fractured reservoirs (Figs. 3.31, 3.32, 3.33, 3.34, 3.35, 3.36, 3.37, 3.38, 3.39, 3.40, 3.41, 3.42, 3.43 and 3.44).

3.6 Reef-Shoal Reservoir

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Fig. 3.14 Three-dimensional spatial characteristics of river channels

Fig. 3.15 Seismic attributes of channel sand bodies in different periods

3.6 Reef-Shoal Reservoir Reef-shoal facies reservoirs generally have obvious facies marks, prominent moundshaped or lenticular geometric shapes, internal chaotic or weak layered reflections, and ‘strings of beads’ reflection characteristics appear when fractures is developed (Figs. 3.45, 3.46, 3.47, 3.48, 3.49, 3.50, 3.51, 3.52, 3.53 and 3.54).

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Fig. 3.16 Seismic attributes of braided river

Fig. 3.17 Schematic diagram of lacustrine delta sedimentary model

3.7 Intrusive Igneous Rock Igneous rocks usually have two formation types: eruption rocks (large volcanic vents, large areas of magma overflowing, magma eject from the ground along large faults and fissures, or along neck-shaped pipes) and intrusive rocks (such as rock basins, rock covers, rock walls, rock stocks, etc.). Different formation type shows different lithofacies. Common igneous facies include intrusive facies, volcanic channel facies, eruption facies, overflow facies, and volcanic deposition facies (Figs. 3.55, 3.56, 3.57 and 3.58).

3.7 Intrusive Igneous Rock

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Fig. 3.18 Seismic response characteristics of delta front sediments (the progradation structure gradually changes from S-type to S-oblique composite type, and the angle of progradation layer is increasing)

Fig. 3.19 Seismic profile characteristics of delta front sand bodies(Oblique progradation structure, fusiform shape)

Fig. 3.20 Seismic profile characteristics of delta front sand bodies

Fig. 3.21 Seismic profile characteristics of delta front sand bodies

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Fig. 3.22 Seismic profile characteristics of the delta underwater distributary channel

Fig. 3.23 Seismic profile characteristics of sand bodies in delta sub-diversion channels

3.8 Eruptive Igneous Rocks See Figs. 3.59, 3.60, 3.61, 3.62, 3.63, 3.64 and 3.65.

3.8 Eruptive Igneous Rocks

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Fig. 3.24 The river channel is slender and spread out

Fig. 3.25 Plane distribution characteristics of multistage channel sand bodies in delta front (amplitude attribute)

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Fig. 3.26 Seismic amplitude attributes characterizing composite sand bodies of underwater distributary channels in braided river delta front (distributed as a curved strip on plane)

Fig. 3.27 Seismic response characteristics of sand bodies in the subdivision channel of the Triassic braided river delta in Tarim Basin (represented by flat top and bottom concave, short event, polarity reversal, and moderate-strong amplitude reflection)

Fig. 3.28 Schematic diagram of sedimentary model of coastal shed sand body

3.8 Eruptive Igneous Rocks

Fig. 3.29 Seismic profile characteristics of the Silurian coastal sand body in Tarim Basin Fig. 3.30 Seismic impedance attributes characterizing the plane distribution of coastal sand body

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Fig. 3.31 Photos of large-scale carbonate caves

Fig. 3.32 Photos of cracks in limestone

3.8 Eruptive Igneous Rocks

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Fig. 3.33 Physical simulation of holes in different scales. a Model parameters: In the formation medium, pore reservoirs are developed with the same shape and different scales, and the pore volume ranges from 5 to 80 m in diameter. The velocity and density of the medium are: VP = 4500 m/s and ρ = 1.34 g/cm3 . The filling velocity and density of the pores are: VP = 2300 m/s and ρ = 1.2 g/cm3 . b By the ultrasonic physical simulation method, a stack profile is obtained with wavelet of 30 Hz main frequency: a hyperbolic diffraction wave is formed at the hole part. The larger the hole scale, the stronger the diffraction wave energy and the longer the hyperbolic extension. c Post-stack migration profile: Different hole scales have significant differences in seismic response characteristics. When the hole diameter exceeds 10 m, beads strong amplitude reflection is formed, which is easier to identify. As the hole scale increases, the length of the bead increases and the amplitude is equivalent

Fig. 3.34 Prestack time migration profile through karst development area

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Fig. 3.35 Prestack time migration profile through karst development area

Fig. 3.36 Three-dimensional display map of karst pleomorphic features (weathering surface shape, yellow–red represents residual hills, blue represents valley)

3.8 Eruptive Igneous Rocks

Fig. 3.37 Plane map of seismic amplitude properties of karst cave system

Fig. 3.38 Coherent attribute Plane map of Karst Landforms

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Fig. 3.39 Three-dimensional display of Ordovician karst cave system in Tarim Basin

Fig. 3.40 Characteristics of “chaotic facies” seismic response of carbonate pore-fracture reservoirs in Tarim Basin

Fig. 3.41 Seismic attribute characteristics of carbonate pore-seam reservoirs (coherent attribute)

3.8 Eruptive Igneous Rocks

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Fig. 3.42 Fracture reservoir characteristics (multi-attribute fusion data volume)

Fig. 3.43 seismic response Characteristics of “weak amplitude chaotic facies” of pore-seam reservoirs in Tarim Basin

Fig. 3.44 Coherent seismic attribute profile of pore-seam reservoirs in Tazhong area, Tarim Basin

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Fig. 3.45 Schematic diagram of platform margin reef-shoal deposition model

Fig. 3.46 Photo of Ordovician reef limestone

3.8 Eruptive Igneous Rocks

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Fig. 3.47 a Model parameters: reef velocity is 5000–5800 m/s, surrounding rock velocity is 6100– 6400 m/s, thickness is 100 m, lateral and longitudinal heterogeneity. b Seismic simulation profile: the top of the reef has a mound-shaped reflection, the bottom boundary has a pull-down phenomenon, and the inside of the reef shows a chaotic or short-event mid-amplitude reflection. c–g Seismic attribute profiles: reefs form significant anomalies in seismic energy, frequency, phase, and wave impedance attributes

Fig. 3.48 Seismic response characteristics of platform margin reefs in Sichuan Basin

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Fig. 3.49 Seismic response characteristics of platform margin reefs in Sichuan Basin

Fig. 3.50 Seismic instantaneous phase attribute profile

Fig. 3.51 Superimposed profile of Multiparameter seismic inversion data and seismic data (reservoir internal reservoir has low impedance characteristics with layered structure)

3.8 Eruptive Igneous Rocks

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Fig. 3.52 Planar attribute features of margin reef

Fig. 3.53 Seismic response characteristics of shoal dolomite reservoirs (syneclise has strong amplitude, shallow shoal at syneclise edge has flat lenticular weak amplitude reflection, and point reef is lenticular weak amplitude reflection of top convex and down concave)

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Fig. 3.54 Seismic response characteristics of shallow clastic limestone pore-seam reservoirs (shoal body is flat lenticular weak amplitude reflection, and biological reefs are lenticular weak amplitude reflections of top convex and down concave)

Fig. 3.55 Geological model of igneous rocks

Fig. 3.56 Seismic profile characteristics of intrusive rocks in Tarim Basin

3.8 Eruptive Igneous Rocks

Fig. 3.57 Seismic profile characteristics of intrusive rocks in Tarim Basin

Fig. 3.58 Seismic profile characteristics of intrusive rocks in Tarim Basin

Fig. 3.59 Seismic profile characteristics of overflow volcanic rocks

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Fig. 3.60 Seismic response characteristics of volcanic rocks in Songliao Basin

Fig. 3.61 Seismic response characteristics of volcanic rocks in Tarim Basin

Fig. 3.62 Seismic response characteristics of volcanic rocks in Tarim Basin

3.8 Eruptive Igneous Rocks

Fig. 3.63 Seismic amplitude attribute characteristics of crater

Fig. 3.64 Seismic profile characteristics of volcanic edifice in Songliao Basin

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Fig. 3.65 Seismic profile characteristics of eruptive phase composite volcanic edifice in Songliao Basin

Chapter 4

Seismic Geological Characteristics of Typical Oil and Gas Reservoirs

This chapter lists three typical examples of oil and gas reservoirs, which mainly illustrate the seismic response characteristics of the main controlling factors (structure, paleomorphology, reservoir, oil and gas bearing, etc.) of the oil and gas reservoir.

4.1 Carbonate Fracture-Cavern Reservoir—The S Reservoir The S reservoir is a typical carbonate fracture-cavern reservoir. Its main reservoir space is large-scale karst caves, eroded caves and fractures. Seismic attributes have achieved good results in the identification and description of caves, holes, and highangle fractures, as well as the characterization of the main controlling factors such as the current structure and ancient geomorphology. (1) Palaeomorphology is the main controlling factor for accumulation See Figs. 4.1 and 4.2. (2) Fracture-cavern reservoir is the key to reservoir formation In terms of seismic response characteristics, the seismic response characteristics of carbonate fracture-cavern reservoirs are: “string of beads” and “chaotic weak reflection” (Zhao 2003) (Figs. 4.3, 4.4, 4.5, 4.6, 4.7, 4.8 and 4.9). The fusion of three attributes of frequency-division impedance, attenuation gradient, and discontinuity establishes the indication parameter of the hole body, which can describe the complex of the seam and hole indicated by the “string of beads” and “chaotic weak reflections” in space (Shouli 2004, 2007) (Figs. 4.10 and 4.11).

© Petroleum Industry Press 2021 S. Qu, Atlas of Typical Seismic and Geological Sections for Major Petroliferous Basins in China, SpringerBriefs in Earth Sciences, https://doi.org/10.1007/978-981-15-6791-9_4

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Fig. 4.1 Schematic section of carbonate fracture-cavern reservoir

Fig. 4.2 Paleo-tectonic morphology of the top of the reservoir in different geohistoric periods

Fig. 4.3 Seismic profile characteristics of karst cave reservoirs

4.1 Carbonate Fracture-Cavern Reservoir—The S Reservoir

Fig. 4.4 Structural map of top surface of reservoir

Fig. 4.5 Seismic profile with east–west direction A-A

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Fig. 4.6 Seismic profile of north–south direction B-B Fig. 4.7 Structural map of top surface of reservoir

4.1 Carbonate Fracture-Cavern Reservoir—The S Reservoir

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Fig. 4.8 Seismic profile Characteristics of hole-seam complexes

Fig. 4.9 Covariance eigenvalue coherent attribute profiles (covariance attributes delineate the distribution of hole-seam complexes)

Fig. 4.10 Seismic profile (top) and fusion profile (bottom)

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Fig. 4.11 Fracture-seam unit sculpted by fusion of seismic data volume (bottom)

4.2 Lithologic Gas Reservoirs in Fluvial Sand Bodies—D Oilfield D gas field is a typical lithologic trap gas reservoir. Multiple sets of gas production layers are stacked. The reservoirs are mainly underwater or water distributary fluvial sand bodies in the transitional facies of the delta plain and the delta front. The physical properties of the reservoirs are controlled by the sedimentary facies (Guan 2006). The main fluvial sand body has large thickness and good physical properties, and it is the main area of the gas field (Figs. 4.12, 4.13 and 4.14).

Fig. 4.12 Profile characteristics of gas layer

4.3 Volcanic Gas Reservoir—Y Gas Reservoir

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Fig. 4.13 Seismic profile characteristics of gas layer

Fig. 4.14 Seismic profile characteristics of gas layer

4.3 Volcanic Gas Reservoir—Y Gas Reservoir The main gas layer of the Y gas field is rhyolite, followed by ignimbrite; the reservoir has good porosity, and the reservoir space is mainly isolated pores or dissolved pores and micro-fractures, with an average porosity of 7.47%. Volcanic facies are mainly eruption facies and overflow facies. Volcanic rocks with multiple and different eruption periods are overlapped (Figs. 4.15, 4.16, 4.17, 4.18, 4.19 and 4.20). Whether volcanic fracture develop affects reservoir performance, and the curvature attribute and variance attribute are sensitive to fracture responses (Figs. 4.21 and 4.22). Seismic wave impedance attribute is sensitive to high-porosity volcanic reservoirs. The development sites of pore fracture show lower seismic wave impedance. The larger the porosity, the lower the seismic wave impedance (Figs. 4.23 and 4.24).

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Fig. 4.15 Indicator parameter inversion profile of pseudo-acoustic reconstruction based on AC-GR crossplot

4.3 Volcanic Gas Reservoir—Y Gas Reservoir

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Fig. 4.16 Gas layer low frequency energy attribute map

Fig. 4.17 Geological model of volcanic gas reservoirs in the Y well block (volcanic rock reservoirs have the characteristics of fast lateral facies change, thin vertical thickness, and multiple layer overlapped) Fig. 4.18 Threedimensional display of volcanic bodies

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Fig. 4.19 Plane distribution of volcanic edifice

Fig. 4.20 Seismic profile through gas reservoir

4.3 Volcanic Gas Reservoir—Y Gas Reservoir

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Fig. 4.21 Curvature attribute profile (red and yellow bars reflect stratigraphic lateral discontinuities, indicating the development of fractures)

Fig. 4.22 Fusion profile of variance attribute and seismic data (red and yellow bars reflect the stratigraphic lateral discontinuity, indicating the development of fractures)

Fig. 4.23 Wave impedance inversion profile (the larger the porosity, the lower the wave impedance)

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Fig. 4.24 Porosity inversion profile (yellow stripe is porous layer)

References Guan DA (2006) Reservoir predicition under the constraint of seismic or sediment phase and application to DND gas field. Geophys Prospect Petrol 45(6): 230–233 Shouli QU (2004) Develop seismic technology to promote the new growth of oil and gas reserves. Petrol Geophys 2:1–5 Shouli QU (2007) Fracture detection by using full azimuth P wave attributes. Appl Geophys 4(3):238–243 Zhao Q (2003) Study of fracture-cave reservoirs from rugged topography with physical modeling technology. Chengdu University of Technology

Appendix

Description of Color Bars in Seismic Profiles

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