In the video produced by the American Petroleum Institute (API) you will learn a bit about how Offshore Seismic Surveying is done:
Some of the richest energy reserves in the world are just off our USA shores waiting to be discovered in a government-owned area lying 3 to 200 miles out to sea. An advanced exploration technique called Seismic Surveying is the first step to unlock this precious resource needed to ensure America’s energy security.
Offshore exploration is highly regulated and performed only in government licensed areas following strict guidelines that protect the vital elements of our marine ecosystem. Well before seismic survey operations begin, safety precautions go into effect to protect marine life. Animal movement and behavior patterns are analyzed and any areas of concern are closed to seismic surveys
During operations, visual and acoustic monitoring is used to detect marine mammals that may be present. Seismic surveying uses compressed air released into the water to create sound waves that penetrate deep into the subsurface rock at the bottom of the ocean. To give animals that may be sensitive to the sound time to leave the area the surveying process begins with a soft start a technique that gradually increases sound to full operational levels.
The survey is conducted by a ship towing a compressed air gun which fires at regular intervals and a large array of sound sensors that record how long it takes for the sound to bounce back from the layers of rock under the seafloor. From the recorded data, detailed three-dimensional maps are produced, these provide engineers the information they need to develop a production plan in order to tap the highest yield reserves.
The maps also pinpoint the safest and most efficient drilling locations, eliminating unnecessary drilling and reducing the number of dry wells. If visual observers or acoustic monitoring devices detect sensitive marine life in the vicinity at any time during the survey process, then all operations stop immediately and are restarted only when the area is clear.
Offshore exploration using seismic surveying and proven safety measures that protect the marine environment enables our nation’s economy to grow and ensures our energy security for future generations.