This paper is part of the Proceedings of the Maritime Cultural Landscape Symposium, October 14-15, 2015, University of Wisconsin-Madison
The Archaeological and Biological Assessment of Submerged Landforms off the Pacific Coast project was launched by BOEM in August of this year, 2015, and BOEM believes it has a lot of potential; however, the previous project—the Inventory and Analysis of Coastal and Submerged Archaeological Site Occurrence on the Pacific Outer Continental Shelf (POCS)—finished in 2013, provides excellent background for understanding the new effort. The Pacific Inventory project was basically a desktop research effort to update our baseline information on archaeological resources on the POCS, similar to what was completed for BOEM in the Gulf of Mexico in 2003 and in the Atlantic region in 2012. This 2013 study of the Pacific updated previous baseline studies that were completed in the Pacific region in 1987 and 1990.
The Pacific Inventory had three components to it. The first was to update our database of historic shipwrecks and provide a geo-referenced database for management and decision-making. The second component was to develop a geo-referenced database of coastal historic properties in order to better understand potential viewshed issues from offshore renewable energy construction. The third component of this 2013 study updated our predictive model for submerged prehistoric sites on the POCS. This included digital elevation modeling (DEM) and a reconstruction of the paleoshorelines in 1,000 year increments, dating back to the Last Glacial Maximum (LGM). For this, numerical values of 1-6 were assigned to 10-meter-grid squares across the POCS, with higher values indicating higher resource areas and more favorable areas for site placement. Stream corridors were expected to have the highest likelihood for containing submerged pre-contact sites. This updated model demonstrated that the southern portion of the POCS had better overall resource potential. However, the southern area also has a narrower shelf and limited stream drainages. Therefore, there are actually more higher value areas concentrated in the northern half of the west coast than in the southern half.
That brings us to this current study (November 2015), the Archaeological and Biological Assessment of Submerged Landforms off the Pacific Coast. As the title suggests, this is a multi-disciplinary effort, looking at both archaeological and biological components of the submerged landforms off the West Coast. It was awarded in August of this year through the California Cooperative Ecosystems Studies unit to San Diego State University. Unlike the previous studies I mentioned, which were desk-based research, this one has a strong field component, which will include geophysical and geological surveys of areas that have a high potential for intact submerged landforms. It’s a four-year effort, building on the 2013 project. Information collected through this effort will support BOEM’s environmental analysis requirements through the National Environmental Policy Act and National Historic Preservation Act.
We have pulled together a strong team of researchers for this project. Todd Braje of San Diego State University is the principal investigator for this project. We are also working with researchers from the University of California Santa Barbara, Oregon State University, SCRIPPS Institute of Oceanography, the University of Oregon, California State University San Bernardino, the Smithsonian Institute, Channel Islands National Park and the Submerged Resource Center of the National Park Service, as well as the Channel Islands National Marine Sanctuary, the NOAA Maritime Heritage Program, and NOAA’s Office of Ocean Exploration and Research.
We are focusing specifically on two areas off the POCS, the Northern Channel Islands off of Southern California and the Central Oregon Coast. The Northern Channel Islands are comprised of four islands: San Miguel, Santa Rosa, Santa Cruz and Anacapa. Previous research on these islands has identified some of the earliest evidence for maritime culture in the Western Hemisphere with sites dating back 9,000 to 13,000 years ago, when those four islands actually composed 1 larger island, referred to as Santa Rosae. As Todd Braje mentioned to me earlier today, the largest concentration of terminal Pleistocene and early Holocene sites are found in this area, concentrated primarily toward the Western end on San Miguel Island.
In addition to the strong evidence of early maritime culture, the islands and the surrounding waters are also protected areas, both through the Channel Islands National Park and the National Marine Sanctuary. A lot of oil and gas activity has also occurred off this area over the last 40 or 50 years; there are at least 15 oil and gas platforms in the area. As a result, there has been a lot of geo-physical survey work done in support of those efforts, and therefore a lot of existing data that we can draw on to build a robust model for identifying intact submerged landforms.
The Central Oregon Coast, on the other hand, has very little existing geophysical survey data available; however, the shelf extends almost 60 km west of the current coastline. There has also been a lot of interest expressed recently in development of renewable energy activity off the Oregon coast. BOEM has actually received two unsolicited applications that we are currently reviewing: one for floating wind turbines off the Coos Bay area; the other application is for wave energy off the Newport area, which is just northeast of the Stonewall Bank area. We have identified the central Oregon coast area as a target area of interest to test the model that we develop off the Northern Channel Islands.
What we are hoping to do with the current study is to provide an assessment of BOEM’s current geophysical survey guidelines for identifying submerged landforms, as well as assess sensitive biological features and expand our knowledge base for the potential for pre-contact sites on the POCS. This supports some of the other research that BOEM has been doing related to seafloor mapping of hydrocarbon and methane seeps, archaeological inventories, and sensitive habitat studies. It also ties in with some related efforts we have going on in the Gulf of Mexico region and the Atlantic region. For example, in 2007, BOEM’s predecessor agency funded Dr. Amanda Evans’ dissertation research through a cooperative agreement with Louisiana State University, which looked at submerged pre-contact sites off the coasts of Texas and Louisiana. We also currently have an ongoing project, which Doug Harris mentioned this morning, working with the University of Rhode Island and the Narragansett Indian Tribe off of the Atlantic coast, trying to identify best practices for identifying submerged landforms and also incorporating oral history and traditional knowledge into those best practices. We are hoping to work with some of the Native American communities on the West Coast in the areas that we’re targeting for this project to see if we can incorporate some of those oral histories and traditional knowledge into this project as well.
The objectives for the submerged landforms project are to develop and field test a geo-spatial model for identifying submerged landforms, with the goal of improving the regional landscape model to assist in BOEM’s decision-making process.
As I mentioned previously, the project was awarded in August of this year (2015) and we have already started compiling all available geophysical survey data. The team has also started refining the 2013 Pacific Inventory model. Fieldwork will focus on the Northern Channel Islands in years one and two, conducting tight grid, high resolution geophysical surveys in four target areas. Once those data are collected and analyzed, we’ll identify areas for sampling with vibro-core and box-cores. In years two and three we will further refine the model and begin testing it off the central Oregon coast. The final year of the project will focus on completing the analysis and writing up the results of the project, which is scheduled for completion in August 2019.
Beyond assisting BOEM in evaluating the potential for encountering cultural resources on the POCS during future energy development, the results from this effort will contribute to the Pacific marine spatial planning efforts and provide a better understanding of the submerged landscape.