Seismic Processing Lab Manual and Wiki using Schlumberger’s Vista Software Package

AASPI

Bryce Hutchinson*, Thang Ha, and Kurt J. Marfurt, University of Oklahoma

Overview (and update from last time) The purpose of this project is to provide a thorough set of instructions for seismic processing. This guide will be utilized in a lab in concert with a course on seismic processing. The lab instructions will eventually be posted as an SEG Wiki.

Wiki Preview – Applying a gain to the dataset

Sample Content (Comparison)

Problem: A very small percentage of students want to deal with the tedium associated with processing seismic data. Leading these students, and future professionals, to accept data as accurate. Objective: Provide students with a flow to better understand how seismic data is processed, while also showing them that errors made in processing can have a large affect on interpreted seismic data. Assumptions: “Hands-on” learning techniques are more effective for today’s students. Providing them with a guide to apply the theory they learn in lecture will lead to a deeper understanding of the theory. Proposal: Develop an online lab manual (wiki) on 3D seismic processing using Vista. Distribute this manual through the SEG, along with 3D prestack land data volume.Challenges: Bridging the gap between theory and practice, and communicate the value of seismic processing to interpretors, especially in avoiding interpretation pitfalls. Solution: Create a comprehensive lab guide that is not intimidating. Include theory in this guide and upload it as a SEG Wiki for public consumption.

Future Work Large strides have been made since the wiki idea was first proposed by Dr. Marfurt. Some work flows still must be added to the lab guide like migration, air wave attenuation, and residual velocity analysis. Once the lab has been outlined and the steps completely recorded, work can begin on converting the instruction set to an SEG Wiki page. The processing lab will originally be created to complement the lecture material. When the Wiki is posted it will need to also include some theoretical ideas that will be covered in the course.

For communication: bdhutchinson@ou.edu

Residual Statics

Figure 8: Flow window that is ready to run. Indicated by the green status bars on each operator.

Figure 7: Right clicking in the flow file window brings up this menu.

Figure 6: New Flow File window with the mouse highlighting the icon to link the operators.

Figure 5: Dialog box editing the name of the output of the flow.

Figure 4: Dialog box for changing the parameters of ExpTPower.

Figure 3: Options listed for input upon double clicking the input operator.

Figure 2: Job flow window after the correct operators (Input, ExpTPower, and Output) have been added to it.

Figure 1: Options listed from the Job Flow tab.

Figure 9: ExpTPower of 1.5

Figure 11: ExpTPower of 3

Figure 10: ExpTPower of 2

Deconvolution

Figure 12: CMP gathers shorted by shot, before deconvolution is applied

Figure 13: Deconvolution applied to the CMP gathers Figure 14: A single CMP before statics is applied. Figure 15: Residual statics applied to a single CMP flattening the signal in the circled areas.

Deconvolution is applied to the data to better image the reflectors and highlight noise by reducing the signal to it’s constituent parts.

Residual Statics flattens the signal along reflectors, creating a more coherent signal.

Yilmaz, Öz, 2001, Seismic data analysis: SEG.