Contact: John Dell'Osso, 415-464-5135
The project undertaken by the National Park Service (NPS) last week has provided researchers at Point Reyes National Seashore with valuable information on the locations of submerged cultural resources within Drakes Bay.
Marine archeologists have determined 20 clusters of anomalies with a high potential for shipwreck material during their week of dragging a sidescan sonar and magnetometer at the bottom of Drakes Bay where over 25 vessels have historically sank.
Many state-of-the-art techniques were experimented with during this project including a specially designed shark net which has shark repellent devices from Shark POD, Inc. These PODs (protective ocean devices) emit an electrical impulse which a shark will immediately retreat from. The protective net for the divers has the PODs strung along the side to protect sharks from the net. A shark cage was also deployed and divers within the cage utilized a tool to move some bottom layers of sand to reveal anomalies.
Personnel from several NPS sites including Point Reyes, San Francisco Maritime National Historical Park, Channel Islands National Park, and the highly specialized dive team from the Submerged Cultural Resources Unit in Santa Fe, New Mexico have joined in a partnership with staff from the Gulf of the Farallones National Marine Sanctuary, the California State Lands Commission, Sonoma State University, the Western Maritime Institute for Archeology, and the Drake Navigators Guild.
The weather during the first week was calm and warm which allowed the magnetometer equipment to give precise readings of anomalies. During conditions when there is considerable wave action, the "noise" from the wave action can cause false readings from the magnetometer.
This first phase of the project will be completed by Friday but it will take researchers several months to analyze all of the data and make some specific recommendations to staff at Point Reyes National Seashore. The project could then be revisited next October for additional underwater work.
Last updated: February 28, 2015