1. Seismic Acquisition A 3D survey is designed based on: Land Operations
Imaging Objectives: image area, target depth, dips, velocity, size/thickness of bodies to be imaged, etc.
Survey Parameters: survey area, fold, offsets, sampling, shooting direction, etc.
Balance between Data Quality & $$$$$
SLIDE 5
Today many of our seismic surveys (both land and marine) are to collect 3D seismic data
However, there still are 2D surveys being collected
We start by asking the ones familiar with the area about what they want to image
E.g, an anticline at 9876 ft covering 10 sq miles and sands believed to be 150 feet thick
This determines the survey parameters
Survey area, the fold, shooting direction, etc.
With seismic acquisition it is always a balance
Good data quality is expensive
What level of quality do you need to answer the business questions?
The left picture is of a land seismic acquisition operation
Four vibrator trucks work in tandem
The right picture is of a marine seismic acquisition ship
In the water you can see 2 airgun arrays
You can also see 4 streamers (cables with hydrophones)
Land Operations
Vibrators Generate a Disturbance
Geophones Detect Motion
Marine Operations
Air Guns Generate a Disturbance
Hydrophones Detect Pressure
Courtesy of ExxonMobil
L 5 – Seismic Method