Controlled-Source Electromagnetic System (CSEM)
CSEM Deployment
The CSEM equipment consists of a transmitter, affixed to a small instrument platform, and a string of 5 receivers, spaced 200m apart along a 1km cable. During installation, the cable and receivers were spooled onto a drum, which was connected to ROCLS. Both of these payloads were lowered by winch from the deck of the R/V Thompson to the seafloor.
The CSEM deployment involved two ROPOS dives and two equipment drops using the ship's winch. The man of the hour during all of this was University of Toronto doctoral candidate Reza Mir, who joined the installation cruise to help coordinate and oversee installation.
Once the ROCLS spool and the transmitter platform were placed on the seafloor, ROPOS flew down, attached to ROCLS, laid the 1km reciever string and recovered ROCLS to the ship. In the following dive, ROPOS again located the transmitter platform, arranged two heavy dipoles on the seafloor nearby, connected it to the receiver string and connected the ODP 889 instrument platform to the CSEM platform.
CSEM on deck. Click to enlarge photo.