Application of Seismic Attributes for Delineation of Channel Geometries and Analysis of Various Aspects in Terms of Lithological and Structural Perspectives of Lower Goru Formation, Pakistan

Tayyab Muhammad Naseer,Farrukh Hussain,Shahid Nadeem Qureshi,Mirza Naseer Ahmad,Shazia Asim

doi:10.4236/ijg.2014.512121

Abstract

Miano area is one of the distinct major hydrocarbon producing fields of the Lower Indus basin. Lower Goru is the reservoir strait in this area. The aim of the present study is to exploit the channels reservoirs and other stratigraphic features in such a terrain where there is always a challenge for the geoscientist to search and exploit the channeled reservoirs. To resolve this issue we have utilized attribute analysis on high resolution 3D-seismic data for the detailed comparative studies for the channels. There are many astonishing features that are identified in the current study, which could not otherwise be easily enhanced with the help of 2D Seismic Data. Seismic attributes such as coherency, frequency (are also appropriate for lithological discrimination), which are sensitive to the channel edges are applied for the channel delineation and their geometrical analysis. Spectral decomposition techniques are also applied for the delineation of channels and to appropriately select the best band for channels identification. Three types of channel geometries are recognized: 1) highly sinuous channel; 2) narrow-broad meandering belts; 3) moderate to high sinuous channel. NW-SE, N-W trending faults can be helpful to compartmentalize the reservoir. Instantaneous and dominant frequency are more beneficial for further field development based on Gamma Ray logs from nearby drilled wells and dimensional perspectives analysis of the channel reservoir.

Highlights

Channels filled with porous rock and enclosed in a nonporous media possess more significant stratigraphic exploration plays
Seismic attributes that are sensitive to the edges of the stratigraphic events (Such as channels) which are coherence, frequency, curvature etc., are the most distinguished means of mapping the channel boundaries [2]
These attributes can detect channel edges, they cannot indicate the channel’s thickness, and when the channel become very thin, their waveforms become constant, such that coherence measures based on waveform shape cannot see the channel at all [3]

Summary

Introduction

Channels filled with porous rock and enclosed in a nonporous media possess more significant stratigraphic exploration plays. Seismic attributes that are sensitive to the edges of the stratigraphic events (Such as channels) which are coherence, frequency, curvature etc., are the most distinguished means of mapping the channel boundaries [2]. These attributes can detect channel edges, they cannot indicate the channel’s thickness, and when the channel become very thin (well below 1/4 wavelength), their waveforms become constant, such that coherence measures based on waveform shape cannot see the channel at all [3]. By the advancement in the seismic attributes, spectral decomposition has highlighted channels [4] [5]. Instantaneous spectra, spectral ratio and phase differences provide measurements for bed thickness variation and absorption [7]

Objectives

Methods

Conclusion