Lophelia II Wreck Component: A Preliminary Archaeological Discussion Daniel J. Warren, Robert A. Church, Robert F. Westrick, C & C Technologies, Inc.

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1 OTC Lophelia II Wreck Component: A Preliminary Archaeological Discussion Daniel J. Warren, Robert A. Church, Robert F. Westrick, C & C Technologies, Inc. Copyright 2011, Offshore Technology Conference This paper was prepared for presentation at the Offshore Technology Conference held in Houston, Texas, USA, 2 5 May This paper was selected for presentation by an OTC program committee following review of information contained in an abstract submitted by the author(s). Contents of the paper have not been reviewed by the Offshore Technology Conference and are subject to correction by the author(s). The material does not necessarily reflect any position of the Offshore Technology Conference, its officers, or members. Electronic reproduction, distribution, or storage of any part of this paper without the written consent of the Offshore Technology Conference is prohibited. Permission to reproduce in print is restricted to an abstract of not more than 300 words; illustrations may not be copied. The abstract must contain conspicuous acknowledgment of OTC copyright. Abstract In 2008, field operations began for a four-year BOEMRE/NOAA/NOPP contract for a multidisciplinary deepwater study examining hard bottom coral habitat in the Gulf of Mexico. The project, officially designated as the Deepwater Program: Natural and Artificial Hard Bottom Habitats with Emphasis on Coral Communities: Reefs, Rigs and Wrecks Lophelia II, is typically referred to as Lophelia II. A substantial component of this contract is the examination of several deepwater shipwrecks. These wrecks represent the remains of four wooden sailing vessels and three steel hull vessels ranging in depth from approximately 612 meters to 2,271 meters. Field investigations utilizing AUV and ROV systems were carried out on these wreck sites during 2008, 2009, and This paper will discuss each of the Lophelia II shipwreck investigations, detailing the methodologies used and findings to date at each site. Introduction In the summer of 2008, the Bureau of Ocean Energy Management, Regulation, and Enforcement (BOEMRE) in partnership with the National Oceanic and Atmospheric Administration Office of Ocean Exploration (NOAA OER) and the National Oceanographic Partnership Program (NOPP) let a contract for a four-year multi-disciplinary study of coral communities on natural and artificial hard bottom areas in the Gulf of Mexico. The study has a substantial historic shipwreck component (historic being defined as a vessel being 50 years of age or older) despite its emphasis on deepwater corals, particularly Lophelis pertusa. These historic shipwrecks represent not only unique underwater ecosystems in the largely featureless continental slope area of the Gulf of Mexico, but also unparalleled information sources about our maritime heritage. A multidisciplinary scientific team of marine archaeologists, biologist, geologists, oceanographers and others have logged five cruises over three field seasons between 2008 and Undertaken from the NOAA research vessels Nancy Foster and Ronald H. Brown and privately contracted ships, these investigations employed Autonomous Underwater Vehicles (AUVs) and Remotely Operated Vehicles (ROVs) to document seven historic shipwreck sites in water depths from 612 to 2,270 meters. This paper reviews operations over the three field seasons, including objectives, technologies, and methods, discusses preliminary findings, and outlines areas of continuing research. Objectives Research and investigation plans for the shipwreck component were designed to meet the project s archaeological objectives of establishing vessel type, construction date, use, and positive identification. Select diagnostic artifacts (e.g. ceramics, construction materials, equipment, or cargo) were collected as necessary to aid in these determinations. Shipwreck features and artifact assemblages were recorded to assist in defining site boundaries, understanding site formation processes, and vessel layout. Anthropogenic and biofouling community impacts were assessed to determine wreck preservation and measure deterioration rates. All of the collected information will be used in conjunction with archival research data to develop an historic context for each wreck and to determine its potential eligibility for nomination to the National Register of Historic Places. Technology Autonomous Underwater Vehicle (AUV). Researchers on the Lophelia II project used both AUV and ROV technologies for the shipwreck investigations. AUVs are unmanned and untethered survey platforms. They can be equipped with a wide range of survey sensors including sonar systems and underwater cameras. AUVs are typically programmed while onboard a surface support vessel with the survey

2 2 OTC parameters, although some systems can be programmed while submerged. Once launched from the surface vessel, the AUV submerges and carries out the pre-programmed operation. Once the mission is completed, the AUV surfaces where it is recovered by the surface vessel and the data uploaded for review. AUV systems can be used on shipwreck sites to collect data for initial assessments and for planning detailed ROV operations. Lophelia II project members used the Sentry and C-Surveyor III AUV systems to collect acoustic and visual data over two of the projects deepwater shipwreck sites (Figure 1). The Sentry AUV was developed and is used by Woods Hole Oceanographic Institutes Deep Submergence Facility (WHOI). It is a deepwater AUV capable of working in water depths up to 4,500 meters. It is equipped with multibeam sonar, magnetometer, and color digital still camera systems. The Sentry photographed and collected multibeam data on the 7,000-Foot Wreck. This data was used to plan the 2009 ROV operations at the site. C-Surveyor III is a Kongsberg HUGIN Class AUV system operated by C & C Technologies, Inc. Like the Sentry, the C- Surveyor III can operate to a depth of 4,500 meters. It carries multibeam and side scan sonars, a subbottom profiler, and a black and white digital still camera. C-Surveyor III collected acoustic data and camera imagery of the Ewing Bank Wreck. This data was used to plan the ROV investigations and to supplement the ROV data for the final wreck assessment for this project. Figure 1. The Sentry AUV (Left) and the HUGIN Class AUV (Right) (Courtesy of the Lophelia II: Deepwater Corals Expedition: Reefs, Rigs, and Wrecks and C & C Technologies, Inc.). Remotely Operated Vehicle (ROV). ROVs are also unmanned survey systems. ROVs, however, are not autonomous. They are controlled through a tether that connects the vehicle to a surface support vessel. Data and commands are transmitted between the ship and the ROV through this tether. As with AUVs, ROVs can carry a variety of equipment including video and still cameras and sonars, as well as manipulator and storage systems for object recovery. ROVs are used for detailed shipwreck investigations, including imagery collection, artifact recovery, and experiment placement and recovery. The two ROVs used for shipwreck investigations on the Lophelia II project were the Saab-SeaEye Falcon DR used during the 2008 field season and the Jason II/Medea ROV system deployed for the 2009 and 2010 field seasons. The SeaEye Falcon is an inspection class ROV that was operated by SeaVision Marine Services, LLC for the project. It is rated to 300 meters and was outfitted with a video and still cameras, as well as a manipulator arm. The Jason II/Medea is a two-part deepwater research ROV system developed and operated by WHOI. Medea is the upper part of the ROV system, while Jason II is the actual vehicle (Figure 2). Both Jason II and Medea are rated to working depths of 6,500 meters. Medea is outfitted with cameras and lights that can illuminate and capture imagery of the seafloor around the Jason II ROV. The Jason II ROV has an integrated collection basket and is outfitted with a variety of sonars, video and still cameras, lights, and a heavy-duty manipulator system.

3 OTC Figure 2. The Jason II ROV (Courtesy of the Lophelia II: Deepwater Corals Expedition: Reefs, Rigs, and Wrecks). Field Operations 2008 Field Operations. The 2008 shipwrecks cruise was the first leg of the BOEMRE/NOAA/NOPP sponsored four-year Lophelia II study. Field operations were carried out from NOAA s Research Ship Nancy Foster using the SeaEye Falcon ROV during September This first shipwreck cruise was designed as a reconnaissance primarily to assess the biological and archaeological potential of eight shipwrecks for inclusion in the project. Secondary tasks to be undertaken at each site, if time allowed, included photomosaics, determination of site boundaries, documentation and collection of corals, setting temperature logging devices, microbiological experiment placement and inspection, and location of the additional wreckage at previously documented sites. Of the eight sites planned for investigation during this cruise, only the Gulfpenn, Viosca Knoll, and Green Lantern wrecks had been previously documented. For the five remaining wrecks, Ewing Bank, tentative Gulfoil, Holly Ann Vieser, the Oval Shape site, and the Steel Hull site this cruise represented the first attempt to visually inspect them. Inclement weather, including Hurricane Ike, and equipment problems plagued the cruise. As a result, only four of the eight shipwrecks, Ewing Bank, Gulfoil, Gulfpenn, and Green Lantern, were inspected. All the primary and secondary cruise objectives were achieved at the Ewing Bank, Gulfoil, and Gulfpenn sites. On the Green Lantern site, post hurricane conditions including low visibility and stronger than normal currents forced operations to be aborted.

4 4 OTC Field Operations. The 2009 field operations for Lophelia II s wreck component were comprised of two AUV cruises and an eight-day ROV investigation cruise focusing on shipwreck documentation. The AUV cruises provided the additional data on the Ewing Bank Wreck and the first imagery of the 7,000-Foot Wreck. The ROV cruise collected detailed archaeological and biological data of the Viosca Knoll, Ewing Bank, Green Lantern, 7,000-Foot, and Gulfpenn shipwrecks (Warren, 2010). The first AUV survey operation took place on June 26, 2009 from the M/V Miss Ginger. As part of an internal testing program the C-Surveyor III AUV collected high-resolution geophysical and still camera images over the Ewing Bank Wreck. The AUV survey consisted of five camera transects over the site at 5-meter line intervals and at an altitude of approximately 8 meters. A total of 64 images were collected of the wreck remains and surrounding area. On completion of the survey, these images were analyzed and a site mosaic produced giving the team its first image of the entire Ewing Bank Wreck. The geophysical data, images, and the site mosaic were used to plan the work for the September 2009 ROV investigations. The second AUV shipwreck investigation was carried out on June 28, 2009 as part of a cruise primarily designed to confirm areas of suspected hard ground and coral sites. The Sentry deployed from the R/V Brooks McCall conducted the first visual survey of the site known as the 7,000-Foot Wreck. The WHOI Sentry AUV flew a survey grid of meter long lines centered over the wreck site. Lines were spaced at 5 meter intervals and flown at 5 meter altitude. At total of 5,160 photographic images as well as multibeam data were collected over the 7,000-Foot Wreck and the surrounding area. This data was used to develop a site map for planning the September ROV visit to the site. The shipwreck leg of the 2009 Lophelia II field operations ran from September 4 to 12, This was the second leg of a two-part cruise season. Operations were carried out from the NOAA Research Vessel Ronald H. Brown using the Jason II/Medea remotely operated vehicle system. The main objective of this leg was the detailed archaeological and biological documentation of five shipwreck sites. Site investigations were successfully carried out carried out at the Viosca Knoll Wreck site, Ewing Bank (EW) Wreck site, the 7,000 ft Wreck site, the Green Lantern Wreck site, and the Gulfpenn wreck site. Diagnostic artifacts were recovered from all the wreck sites except the Gulfpenn. These artifacts were stabilized for transport by University of West Florida (UWF) archaeological conservation staff before being transferred to UWF for final conservation at the end of the cruise Field Operations. The 2010 Lophelia II shipwreck investigations took place during the second half of the scheduled cruise period between October 24 and November 4. The 2010 operations were also carried out from the NOAA Research Vessel Ronald H. Brown using the Jason II/Medea remotely operated vehicle system. The primary objective of this segment of the cruise was to document hard bottom coral areas so only a single shipwreck site, the Gulfoil, was scheduled for examination. Investigations of the Gulfoil were undertaken on October 27, During the site visit the main wrecksite and two debris zones were documented using Jason II s onboard camera systems. Following the investigations of the Gulfoil, while surveying hardbottom areas south of the Deepwater Horizon oil spill site, the research team had an opportunity to visit the U-166 wreck site to assess any potential impacts from the oil spill to the wreck. An attempt to visit the nearby wreck of the Robert E. Lee was aborted after a short circuit caused a catastrophic electric failure on the Jason II ROV. Following the recovery of Jason II, time constraints and deteriorating weather led to the cruise s termination. Shipwreck Investigation Preliminary Findings All seven of the historic shipwrecks visited during the Lophelia II project were discovered during natural resource exploration surveys conducted by commercial survey companies. Three of the shipwrecks, Gulfoil, Gulfpenn, and U-166 are World War II era steel vessels. The remaining four shipwrecks, Viosca Knoll, 7,000-Foot, Ewing Bank, and Green Lantern are wooden sailing ships. Viosca Knoll Wreck. This wreck, referred to as the Viosca Knoll Wreck or VK Wreck, is named for the block area where it is located. Lying 612 meters below the surface, this wreck was discovered during a deep-tow survey in 2003 and surveyed with an AUV in May Initial ROV investigations at the site took place in July 2006 as part of an MMS study ( ). The site represents the remains of a copper-clad sailing vessel measuring 45 meters in length and 10 meters wide (Figure 3). Small colonies of Lophelia pertusa can be found at various locations throughout the site. During the 2009 field season the research team conducted a detail examination of the Viosca Knoll Wreck. While on site, researchers noted extensive repair work to the copper sheathing on the hull. They also located remnants of rigging and mast hardware on the vessel s starboard side as well as a large section of mangled rigging and scattered artifacts 140 meters southwest of the hull. A survey of the wreck s stern found it almost completely disintegrated. The surrounding seafloor is strewn with fragments of the disarticulated sternpost, pintle and gudgeon remnants, and every day shipboard artifacts that have spilled out of the hull. The research team recovered a sample of copper sheathing and a stoneware ceramic water filter from the stern area. The water filter is of English manufacture and dates to the last quarter of the nineteenth century.

5 OTC Figure 3. The bow of the Viosca Knoll Wreck (Courtesy of the Lophelia II: Deepwater Corals Expedition: Reefs, Rigs, and Wrecks). 7,000-Foot Wreck. The 7,000-Foot Wreck is actually located in approximately 2,271 meters (7,450 feet) of water in the Mississippi Canyon Area. Although initially located in 1986 and resurveyed in 2006 during oil and gas lease surveys, it was not until the 2009 Sentry AUV survey that the first site photographs were collected. These images showed a small copper clad sailing vessel approximately 18 meters in length and 5 meters in beam. The 2009 ROV investigations revealed an exquisitely preserved wreck. Although the upper deck has collapsed downward, the stem post, including remnants of the beak, are intact and upright at the bow (Figure 4). At the stern, the steering mechanism, including the wheel, stands prominently above the collapsed decking. Investigations revealed a number of intact ship components and shipboard artifacts, including the ship s overturned windlass, stove, water barrels, ceramic jugs, and compass. The ship s compass, located at the stern just forward of the ship s wheel in what would have likely been the helm area, was recovered from the site. Inscriptions on the compass indicate a manufacture date range of 1874 to Initial assessment indicates the wreck is similar in size and design to late nineteenth and early twentieth century pilot schooners. Figure 4. Bow Remnants of the 7,000-Foot Wreck. (Courtesy of the Lophelia II: Deepwater Corals Expedition: Reefs, Rigs, and Wrecks).

6 6 OTC Ewing Bank Wreck. First discovered in 2006 the Ewing Bank Wreck was visually inspected for the first time during the 2008 Lophelia II field season. The vessel is a wooden copper clad sailing vessel approximately 40 meters long and 10 meters wide at the beam. The wreck is in approximately 621 meters of water and has extensive colonies of Lophelia growing on the stempost extending several feet up into the water column (Figure 5). In early 2009, the wreck was photographed using C-Surveyor III. In September 2009 detailed investigations commenced using the Jason II ROV. The Ewing Bank Wreck is unusual in that, unlike most of the other wrecks on this project, it is relatively devoid of rigging, fittings, and other ship related materials. A small cluster of ceramics in the vessel s stern is the only visible concentration of artifacts. The wreck is essentially a copper shell since the upper hull and much of the exposed interior framing has deteriorated. Numerous patches in the copper sheathing indicate the vessel s longevity. Keelson and ballast stone remnants are visible inside the hull, and there appear to be stratified hull remains on the wreck s port exterior. A segment of modern net is tangled on the stern, indicating the net may have snagged and damaged the stern structure. The research team recovered a piece of the net and a small ironstone container from the site. Initial analysis suggests this vessel may have been a deepwater sailing vessel that was converted into a barge. Figure 5. Bow remains at the Ewing Bank Wreck Site (Courtesy of the Lophelia II: Deepwater Corals Expedition: Reefs, Rigs, and Wrecks). Green Lantern Wreck. The Green Lantern derives its name from one of the ship s copper lanterns found on the wreck that had developed a green patina from exposure to seawater. First located in 1996 and resurveyed in 2004, the wreck has been inspected by ROVs several times. This 20-meter long wooden copper clad sailing vessel sits upright on the seafloor at a depth of 914 meters. Attempts to visit the site during the 2008 field season were thwarted by adverse seafloor conditions following Hurricane Ike. The 2009 field investigation was the most in-depth study of the site to date. Data shows that the hull of the vessel below the water line is mostly intact. The stempost, complete with bobstay fittings, extends nearly 2 meters into the water column (Figure 6). A windlass rests on the seafloor on the port exterior of the wreck. Also on the port side remnants of mast rigging and couplings mark the location where a wood mast, now completely disintegrated, once rested on the seafloor. The rudder is mostly buried but is still attached to the sternpost that rises over a meter above the seafloor. Silverware, ceramics, glassware, and ship components are found on the wreck site. In 2009, researchers recovered the ship s bell, a navigation lantern, a small ceramic dish, and a dinner fork from the site. Based on the manufacture date of the ceramic dish and the dinner fork, the Green Lantern Wreck is thought to have sunk after 1905.

7 OTC Figure 6. The Bow of the Ewing Bank Wreck (Courtesy of the Lophelia II: Deepwater Corals Expedition: Reefs, Rigs, and Wrecks). Gulfpenn. Gulfpenn was built in 1921 as an 8,862-ton tanker. On May 13, 2003, it left Port Arthur, Texas loaded with ninety thousand barrels of fuel oil. At mid-afternoon the tanker was struck in the engine room by a torpedo from U-506. Twentyfive of the crew survived the attack but thirteen perished (Church, 2007). The vessel was located in 1994 and investigated in 2004 as part of the Deep Wrecks I Study (MMS ). At a water depth of 569 meters, this site has extensive Lophelia coverage as well as deep reef fish and other invertebrates. As part of the previous MMS study, test coupons were left at the site to assess deterioration rates (Church et al. 2007). This wreck is considered historically significant and a National Register Nomination was prepared for this site as part of the Deep Wrecks I Study. Gulfpenn was revisited during the 2008 field season. During this visit archaeologists verified a large section of debris forward of the main hull as the stern section of the vessel. In 2009, researchers returned to the Gulfpenn. These investigations focused on documenting the Lophelia colonies and biologic activity on the wreck, so archaeological investigations were limited to documentation of portions of the bridge structure (Figure 7). Figure 7. Lophelia coral on the bow of the Gulfpenn (Courtesy of the Lophelia II: Deepwater Corals Expedition: Reefs, Rigs, and Wrecks).

8 8 OTC Gulfoil. The Gulfoil was a 5,188-ton tanker built in On May 16, 1942, the tanker left Port Arthur, TX with a cargo of petroleum headed for New York City. At 10:41 the same night a torpedo struck the tanker amidships on the starboard side. Minutes later a second torpedo hit the engine room. The ship listed hard to starboard and went down fast taking twenty-one crewmembers with her (Church, 2007). Investigations were carried out on the suspected Gulfoil site at a depth of 534 meters on September 15, 2008, from the R/V Nancy Foster. Although hampered by currents and low visibility, the SeaEye ROV successfully surveyed approximately 45 meters of the starboard side of the wreck site. The team found the wreck covered with extensive Lophelia colonies and positively identified the wreck as Gulfoil from the name on the bow. Adverse bottom conditions and equipment problems prevented further investigations. The Gulfoil was not visited in 2009, but researchers returned to the site in The Gulfoil was the only wreck investigation officially scheduled for the 2010 field cruises. Examination of the site took place on October 27, Initial inspection of the sites showed that the wreck is extensively covered by dense growths of Lophelia coral colonies. During this visit, researchers completed a 360-degree video documentation of the main hull and confirmed that two nearby debris zones were associated in the wreck. They also located the Gulfoil s deck gun and documented torpedo holes in the starboard side of the vessel. In addition, to video imagery, the high-definition still camera was used to capture images for a profile mosaic and to document key wreck features (Figure 8). Finally, the ROVs downward looking camera was used to image two plan view mosaic transects over the top of the Gulfoil. The data from the 2010 inspection is currently being reviewed and a wreck site assessment is underway. Figure 8. Bow mosaic of the Gulfoil (Courtesy of the Lophelia II: Deepwater Corals Expedition: Reefs, Rigs, and Wrecks).

9 OTC U-166. U-166 is a type IXC German U-boat. Located in just over 1,500 meters of water in the Mississippi Canyon Area, the site represents the remains of the only World War II German U-boat lost in the Gulf of Mexico (Figure 9). U-166 was destroyed by depth charges from the naval patrol craft PC-566 on July 30, 1942 shortly after two torpedoes from the U-boat sank the passenger freighter Robert E. Lee. After 60 years of mystery surrounding the location of the wreck, U-166 s remains were identified in The wreck site was extensively documented during a 2003 NOAA Office of Ocean Exploration funded project and the 2004 Deep Wrecks Project supported by BOEMRE, NOAA OER, and NOPP. The U-166 site was not scheduled for examination during the 2010 Lophelia field season. However, while investigating hard bottom areas south of the Deepwater Horizon oil spill site an opportunity arose to visit U-166. The site visit s primary objective was to determine if the oil spill had impacted the wreck. During the site inspection, high-definition video was collected of the stern and bow sections, and the microbiological experiments placed on the wreck in This data will be compared to the information from the 2003 and 2004 investigations to document any physical changes in the wreck and to assess site preservation and deterioration. Based on initial observations, there was no visibly apparent impact to the site from the Deepwater Horizon oil spill. Figure 9. The conning tower and stern section of U-166 (Courtesy of the Lophelia II: Deepwater Corals Expedition: Reefs, Rigs, and Wrecks). Conclusions Over three field seasons between 2008 and 2010, researchers successfully completed the Lophelia II Project s shipwreck investigation program. During this time, seven historic shipwrecks were comprehensively documented using state-of-the-art deepwater survey technology. The digital data, physical remains, and environment samples recovered are helping researchers understand each ship s past use, its formation as a shipwreck site, and its functions as a deepwater ecosystem. Preliminary assessments have already yielded interesting results and illuminated new avenues for research. As analysis continues a clearer picture of each shipwreck will emerge resolving more questions and, undoubtedly, evoking many more. Acknowledgments The authors would like to thank TDI Brooks International, C & C Technologies, Inc., BOEMRE, NOAA OER, and NOPP for their support and funding without which the shipwreck investigations could not have been undertaken. We would also like to extend our appreciation the marine survey crews from C & C Technologies, Inc., TDI Brooks International, John Chance and Associates, and FUGRO whose efforts led to the discovery of many of the sites studied for this project. Finally, thank you to the crews of the NOAA research vessel s Nancy Foster and Ronald H. Brown as well as the WHOI Jason II/Medea ROV team whose tireless efforts and unprecedented skills were key to the success of the Lophelia II Project.

10 10 OTC References Church, R., Warren, D., R. Cullimore, L. Johnston, M. Kilgour, J. Moore, N. Morris, W. Patterson, W. Schroeder, and T. Shirley, 2007, Archaeological and Biological Analysis of World War II Shipwrecks in the Gulf of Mexico: Artificial Reef Effect in Deepwater, U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OCS Region, New Orleans, LA. OCS Study MMS , 2007, pp Warren, D, Church, R., Westrick, R., 2010, Archaeological Assessment of the Lophelia II: Rigs, Reefs, and Wrecks Interim Report, unpublished.