Seismic Data Interpretation and Identification of Hydrocarbon-Bearing Zones of Rajian Area, Pakistan

The present study interprets the subsurface structure of the Rajian area using seismic sections and the identification of hydrocarbon-bearing zones using petrophysical analysis. The Rajian area lies within the Upper Indus Basin in the southeast (SE) of the Salt Range Potwar Foreland Basin. The marked horizons are identified using formation tops from two vertical wells. Seismic interpretation of the given 2D seismic data reveals that the study area has undergone severe distortion illustrated by thrusts and back thrusts, forming a triangular zone within the subsurface. The final trend of those structures is northwest–southeast (NW–SE), indicating that the area is part of the compressional regime. The zones interpreted by the study of hydrocarbon potential include Sakessar limestone and Khewra sandstone. Due to the unavailability of a petrophysics log within the desired investigation depths, lithology cross-plots were used for the identification of two potential hydrocarbon-bearing zones in one well at depths of 3740–3835 m (zone 1) and 4015–4100 m (zone 2). The results show that zone 2 is almost devoid of hydrocarbons, while zone 1 has an average hydrocarbon saturation of about 11%.

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Seismic data interpretation for mapping the subsurface structure thickness of top and base parigi formation, Konro field, northern West Java basin

Journal of Physics Conference Series ◽

10.1088/1742-6596/1876/1/012019 ◽

2021 ◽

Vol 1876 (1) ◽

pp. 012019

Author(s):

R Rafiandi ◽

R F Indriani ◽

M Mariyanto

Keyword(s):

Seismic Data ◽

Data Interpretation ◽

Subsurface Structure ◽

West Java ◽

Structure Thickness

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Feasibility of CDP seismic reflection to image structures in a 220-m deep, 3-m thick coal zone near Palau, Coahuila, Mexico

Geophysics ◽

10.1190/1.1443206 ◽

1992 ◽

Vol 57 (10) ◽

pp. 1373-1380 ◽

Cited By ~ 4

Author(s):

Richard D. Miller ◽

Victor Saenz ◽

Robert J. Huggins

Keyword(s):

Seismic Data ◽

Seismic Reflection ◽

Subsurface Structure ◽

Reflection Method ◽

Accurate Identification ◽

Common Depth Point ◽

Seismic Reflection Method ◽

The Common ◽

Zone Depth ◽

Seismic Sections

The common‐depth‐point (CDP) seismic‐reflection method was used to delineate subsurface structure in a 3-m thick, 220-m deep coal zone in the Palau area of Coahuila, Mexico. An extensive series of walkaway‐noise tests was performed to optimize recording parameters and equipment. Reflection events can be interpreted from depths of approximately 100 to 300 m on CDP stacked seismic sections. The seismic data allow accurate identification of the horizontal location of the structure responsible for a drill‐discovered 3-m difference in coal‐zone depth between boreholes 150 m apart. The reflection method can discriminate folding with wavelengths in excess of 20 m and faulting with offset greater than 2 m at this site.

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Application of 3D Seismic Data Interpretation in Depositional Modeling: Selat Asam Field, Central Sumatra

10.29118/ipa.2286.185 ◽

2018 ◽

Author(s):

Tiur Aldha

Keyword(s):

Seismic Data ◽

Data Interpretation ◽

3D Seismic ◽

Central Sumatra ◽

3D Seismic Data

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Pitfalls and limitations in seismic attribute interpretation of tectonic features

Interpretation ◽

10.1190/int-2014-0122.1 ◽

2015 ◽

Vol 3 (1) ◽

pp. SB5-SB15 ◽

Cited By ~ 64

Author(s):

Kurt J. Marfurt ◽

Tiago M. Alves

Keyword(s):

Seismic Data ◽

Seismic Attributes ◽

Seismic Attribute ◽

3D Data ◽

Amplitude Data ◽

Seismic Sections ◽

Push Down ◽

Data Coherence ◽

Level Of Experience ◽

Tectonic Features

Seismic attributes are routinely used to accelerate and quantify the interpretation of tectonic features in 3D seismic data. Coherence (or variance) cubes delineate the edges of megablocks and faulted strata, curvature delineates folds and flexures, while spectral components delineate lateral changes in thickness and lithology. Seismic attributes are at their best in extracting subtle and easy to overlook features on high-quality seismic data. However, seismic attributes can also exacerbate otherwise subtle effects such as acquisition footprint and velocity pull-up/push-down, as well as small processing and velocity errors in seismic imaging. As a result, the chance that an interpreter will suffer a pitfall is inversely proportional to his or her experience. Interpreters with a history of making conventional maps from vertical seismic sections will have previously encountered problems associated with acquisition, processing, and imaging. Because they know that attributes are a direct measure of the seismic amplitude data, they are not surprised that such attributes “accurately” represent these familiar errors. Less experienced interpreters may encounter these errors for the first time. Regardless of their level of experience, all interpreters are faced with increasingly larger seismic data volumes in which seismic attributes become valuable tools that aid in mapping and communicating geologic features of interest to their colleagues. In terms of attributes, structural pitfalls fall into two general categories: false structures due to seismic noise and processing errors including velocity pull-up/push-down due to lateral variations in the overburden and errors made in attribute computation by not accounting for structural dip. We evaluate these errors using 3D data volumes and find areas where present-day attributes do not provide the images we want.

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On the Processing of Non-Rectangularly Sampled Multi-Dimensional Geophysical Data

International Journal of Modern Physics C ◽

10.1142/s0129183191000214 ◽

1991 ◽

Vol 02 (01) ◽

pp. 223-226

Author(s):

VIRGIL BARDAN

Keyword(s):

Seismic Data ◽

Geophysical Data ◽

Seismic Sections

In this paper the processing of triangularly sampled 2-D seismic data is illustrated by examples of synthetic and field seismic sections.

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Using Logging and Seismic Data to Identify Boundaries Between Different OWC Units in a Deepwater Carbonate Reservoirs

10.2523/iptc-21438-ms ◽

2021 ◽

Author(s):

Kangxu Ren ◽

Junfeng Zhao ◽

Jian Zhao ◽

Xilong Sun

Keyword(s):

Seismic Data ◽

Carbonate Rocks ◽

Carbonate Reservoir ◽

Carbonate Reservoirs ◽

Sedimentary Process ◽

Core Samples ◽

Tight Carbonate ◽

Porosity And Permeability ◽

Seismic Sections ◽

Parameters Inversion

Abstract At least three very different oil-water contacts (OWC) encountered in the deepwater, huge anticline, pre-salt carbonate reservoirs of X oilfield, Santos Basin, Brazil. The boundaries identification between different OWC units was very important to help calculating the reserves in place, which was the core factor for the development campaign. Based on analysis of wells pressure interference testing data, and interpretation of tight intervals in boreholes, predicating the pre-salt distribution of igneous rocks, intrusion baked aureoles, the silicification and the high GR carbonate rocks, the viewpoint of boundaries developed between different OWC sub-units in the lower parts of this complex carbonate reservoirs had been better understood. Core samples, logging curves, including conventional logging and other special types such as NMR, UBI and ECS, as well as the multi-parameters inversion seismic data, were adopted to confirm the tight intervals in boreholes and to predicate the possible divided boundaries between wells. In the X oilfield, hundreds of meters pre-salt carbonate reservoir had been confirmed to be laterally connected, i.e., the connected intervals including almost the whole Barra Velha Formation and/or the main parts of the Itapema Formation. However, in the middle and/or the lower sections of pre-salt target layers, the situation changed because there developed many complicated tight bodies, which were formed by intrusive diabase dykes and/or sills and the tight carbonate rocks. Many pre-salt inner-layers diabases in X oilfield had very low porosity and permeability. The tight carbonate rocks mostly developed either during early sedimentary process or by latter intrusion metamorphism and/or silicification. Tight bodies were firstly identified in drilled wells with the help of core samples and logging curves. Then, the continuous boundary were discerned on inversion seismic sections marked by wells. This paper showed the idea of coupling the different OWC units in a deepwater pre-salt carbonate play with complicated tight bodies. With the marking of wells, spatial distributions of tight layers were successfully discerned and predicated on inversion seismic sections.

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Fault Detection by Using Instance Segmentation

10.2523/iptc-21249-ms ◽

2021 ◽

Author(s):

Donglin Zhu ◽

Lei Li ◽

Rui Guo ◽

Shifan Zhan

Keyword(s):

Fault Detection ◽

Seismic Data ◽

Semantic Segmentation ◽

Data Interpretation ◽

Machine Learning Methods ◽

Segmentation Algorithms ◽

Direct Recognition ◽

First Time ◽

Seismic Images ◽

Instance Segmentation

Abstract Fault detection is an important, but time-consuming task in seismic data interpretation. Traditionally, seismic attributes, such as coherency (Marfurt et al., 1998) and curvature (Al-Dossary et al., 2006) are used to detect faults. Recently, machine learning methods, such as convolution neural networks (CNNs) are used to detect faults, by applying various semantic segmentation algorithms to the seismic data (Wu et al., 2019). The most used algorithm is U-Net (Ronneberger et al., 2015), which can accurately and efficiently provide probability maps of faults. However, probabilities of faults generated by semantic segmentation algorithms are not sufficient for direct recognition of fault types and reconstruction of fault surfaces. To address this problem, we propose, for the first time, a workflow to use instance segmentation algorithm to detect different fault lines. Specifically, a modified CNN (LaneNet; Neven et al., 2018) is trained using automatically generated synthetic seismic images and corresponding labels. We then test the trained CNN using both synthetic and field collected seismic data. Results indicate that the proposed workflow is accurate and effective at detecting faults.

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