2 D HIGH RESOLUTION MARINE SEISMIC DATA PROCESSING BY USING SEISMIC UNIX: PART- 3: GEOMETRY SETTING

DESCRIPTION:
Geometry setting is an updating trace identity, consists of shot coordinate, group (receiver) coordinate,  source-receiver offset, and also setting common depth point (CDP). The objective of geometry setting is to obtain valid trace header values from acqusition geometry, especially the information belonging to the same subsurface depth (CDP) for improving S/N ratio.

Geometry setting requires acquisition parameters and navigation data.  Either recorded navigation in an external file such as UKOOA P1/90 format (*.p190) or registered in the trace header is used to set geometry. Trace headers must already have the correct geometry values inserted. It is very important to define the source and receiver coordinate location. Acquisition parameters are also needed to calculate appropriate values for common depth point (CDP).

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2 D HIGH RESOLUTION MARINE SEISMIC DATA PROCESSING BY USING SEISMIC UNIX: PART- 2: TRACE EDITING

DESCRIPTION:
Before setting geometry, applying signal enhancement, and further processing, it is necessary to edit the incorrect traces and to kill bad traces. If any, the content of incorrect polarity and bad traces can be obtained from observer log or done manually from trace display observation.

The objective of trace editing is to correct bad traces to be good traces. In this stage, we will eliminate the “misfire” records, delete auxiliary traces, reverse incorrect trace polarity (if any), and kill dead traces (if any) from previously processed data. Thus, we may obtain decent data to be used for the next processing stage.

Author : Henry Mulana Nainggolan
Date    : May 4th, 2014

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2 D HIGH RESOLUTION MARINE SEISMIC DATA PROCESSING BY USING SEISMIC UNIX: PART-1: SEG-Y INPUT

INTRODUCTION

Seismic data processing converts seismic data recordings into meaningful seismic sections that reveal and help delineate the earth subsurface stratigraphy and structure that may bear fossil hydrocarbons. Three main objectives of seismic data processing: correcting static and location, increasing signal/noise ratio, and improving resolution. Those can be implemented by various techniques of processing stages which are beyond the scope of mathematical, geological, and physics concepts. 

There are many processing softwares, the most usual and commercial software such as ProMAX, Omega, Vista, Focus, etc. Apart of them, there are also many freeware and open-source processing softwares. Seismic Unix (SU) package is a most usual, fast release & freeware processing tools under Linux/Unix developed and maintained by the Center for Wave Phenomena (CWP) at Colorado School of Mines. The full source code packages are distributed and can be downloaded on http://www.cwp.mines.edu/cwpcodes/index.html or via ftp://ftp.cwp.mines.edu/pub/cwpcodes.

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