3D Seismic field terminology

 

Source Line

A line that has some type of energy release (Dynamite/Vibroseis/Weight drop/Airgun) at specified intervals within a seismic program.

Receiver Line

A line that has sensors (Geophone/Hydrophone) laid out at specified intervals within a seismic program.

Source Line Interval

The distance between 2 adjacent source lines.

Receiver Line Interval

The distance between 2 adjacent receiver lines.

Source Interval

The distance between adjacent source points along a source line.

Receiver Interval

The distance between each group of receivers (or single sensors) along a receiver line.

In-line Direction

The direction parallel to the receiver lines.

Cross-Line Direction

The direction perpendicular to the receiver lines.

Recording Patch

All stations (receiver points) that are actively recording for a given shot point. 

Typically defined by the: (# of receiver lines) X (# of receivers per line).

Swath / Salvo

All the shot points between adjacent receiver lines.

recording patch methodology

Rolling on / rolling off:

The process of recording with a partial patch on the edges of the seismic program. This process ensures that the required offsets are obtained while avoiding the acquisition of unnecessary far-offsets, thus maximizing the field crew's efficiency.

Recording Patch Types:

All-Live

All stations (receivers) in a 3D seismic program are actively recording data for all shot points on the project.

Roll Lines

Complete lines of station (receivers) are actively recording data as the seismic program is being acquired. You will notice that the first shot point in the project will have 1/2 of the full recording patch.

Roll Lines and Stations

Lines and station (receivers) are actively recording data as the seismic program is being acquired. You will notice that the first source point in the project will only have 1/4 of the full recording patch

Below is an animated example of Roll-on / Roll-off Seismic Acquisition: