CORK Optical Telemetry System

Woods Hole Oceanographic Institution, Woods Hole MA

Investigators

Abstract

The PIs request funding to build, test and deploy an optical telemetry system (OTS) designed for an instrumented seafloor borehole observatory. A series of boreholes drilled on the flanks of the Juan de Fuca ridge in the northeast Pacific have been instrumented as part of the ODP CORK program and are visited on a regular basis for downloading data and for collecting physical samples of subsurface fluids. This installed infrastructure provides a unique opportunity for installing and testing an optical communications node in relatively controlled conditions. CORK borehole monitoring reveals a very broadband signal from tidal loading and ocean waves to teleseismic activity. Present data rates are limited by several factors but communication rate is the most constraining. Greater sample rates are required to properly sample high frequency signals that include tsunamis and other oceanographic phenomena. Highspeed underwater optical communications will remove this bottle-neck and allow seafloor instruments to collect data at scientifically relevant data rates. The proposed CORK-OTS would simply plug into the existing underwater connectors on the CORK and would provide additional capability such as data storage and the ability for rapid data retrieval either by periodic visits by a submersible or perhaps more importantly in a remote-mode by using an optical receiver lowered by a cable from the sea surface. Broader Impacts The proposed work is an enabling technology that will enhance the infrastructure for research and education in all fields of oceanography. The PIs plan to establish new collaborations with an international partner in Canada, the Pacific Geoscience Center, and with academic colleagues at other universities. In addition, the CORK-OTS may be deployed at other International Ocean Drilling Program sites around the globe. The publication of the results of the proposed work in journals and conferences will enhance science education and technology. The PIs also plan to integrate the proposed research work in their educational activities, which include the hiring of high school students and college undergraduates during the summer periods in their laboratory. The development of the underwater OTS may offer opportunities for commercialization of the technology by government and industry for such use as environmental monitoring and other potential applications.