The objective of this project was to collect acoustic images from the continental shelf off the coast of New Jersey to obtain evidence of climate change from the geologic record. Over six weeks in the summer of 2015, a team deployed a 3-kilometer hydrophone streamer and a P-Cable system with 24 streamers and 96 hydrophones each to collect seismic data. Navigation of the seismic equipment was done using GPS systems. The author's duties included monitoring the single streamer data collection, observing the seismic source, aiding with deployment and recovery of equipment, and later controlling the spare reel holding the P-Cable streamers.

1. Calibration and deployment of a 3D P-cable to collect evidence of climate change
Tyler Hackett, MATE intern (summer 2015)
Advisor: Dr.Gregory Mountain, Robert Steinhaus
The objective of this project was to obtain acoustic images of
the geologic record of climate change from the continental
shelf 30km to 80km off the coastline of New Jersey. The
research was conducted over a period of six weeks during the
summer of 2015. Two seismic acquisition systems were used
to collect the data, a three-kilometer hydrophone streamer
which was used to accurately measure sound velocities to
calibrate the P-Cable, which was the main acquisition system.
• 235 Ft (71 m)
• 55 personnel
DEPLOYMENT / RECOVERY
OBJECTIVE OPERATION
RV Langseth SIESMIC SOURCE
• 4 Bolt air guns
• 700 in3 Total @ 2000 PSI
P-CABLE SYSTEM
• 24 streamers
• 96 Hydrophones per
streamer
• 12.5 meters apart
SET-UP
Navigation of the entire seismic survey was completed using
NCS Subsea technologies. Attached to each of the GPS
buoys, paravanes, and seismic source was a GPS that
communicated with the navigation software. This software
gave a visual representation of the orientation of the seismic
equipment and the area of the prospect where data was
obtained as seen by the green on the map below.
While obtaining data each individual on duty had a specific job.
My main responsibility consisted of starting, monitoring, and
shutting off the single steamer data collection. Another
responsibility of mine was to observe the seismic source string
to make sure there were not any issues. While monitoring I
had to log any events along the line including start and end of
line, any animal power-downs, or technical difficulties.
The deployments of the seismic systems were unique. The
single 3-km long off-set streamer was the first to be deployed.
This included the streamer levelers also known as birds being
attached to control the depth of the streamer as it was towed.
To deploy the full P-Cable system, the single streamer had to
be pulled to the port side. Then the starboard paravane and
GPS buoy were deployed and the P-Cable quickly followed.
After each short streamer was attached to the P-Cable, tests
were performed to make sure the communication was
operating properly. This continued until all 24 streamers were
deployed. The port paravane and port GPS buoy were then
deployed and spooled out to the final position. This process
took every technician on shift to safely and efficiently deploy
the entire system.
My duties consisted of aiding the technicians in safely
deploying the paravanes and GPS buoys. Later on in the
cruise my duties shifted to the more responsible position of
controlling the spare reel that held all of the P-Cable
streamers. I was also able to get hands-on experience
deploying and recovering the seismic source. All of these jobs
required above average communication and focus.
NAVIGATION
P-CABLE SOFTWARE
The P-Cable software that was developed by Geometrics was
used to obtain the data only from the P-Cable system. This
software gives an image of sound reflected off layered
sediments below the sea floor. The real time data is used to
observe if there are any other sounds being picked up that are
not of our interest. These noises include ship noise, issues
with the air source and other interferences. Below is an
example of the software.
The MATE Internship Program is funded by the REU program of the National Science
Foundation’s Division of Ocean Sciences. Since 1999, the MATE internship program has
placed over 300 students in at-sea internships lasting from two weeks to six months. More
information about the program can be obtained at: http://www.marinetech.org/internships/