Texas A&M University (TAMU) is at the forefront of deepwater shipwreck exploration in the Gulf of Mexico and around the world. A team of nautical archaeologists and oceanographers from the university have been collaborating with the Minerals Management Service (MMS) of the US Department of the Interior, the US Navy, and private corporations to investigate and identify some of the hundreds of shipwreck sites located on the outer continental shelf and slope.

The enthusiasm of this partnership has resulted in the exploration of the Mica shipwreck, the identification of the Western Empire, a survey of World War II Japanese submarines, and a proposed International Archaeological Oceanography Center to be based at the university.

In addition, TAMU is forming a strategic partnership with Houston-based contractor Deep Marine Technology (DMT) and the MMS. DMT will provide exploration equipment and logistical support, including surface vessels, ROVs, and pilots, while TAMU will provide oceanographers and nautical archaeologists, with the MMS supplying shipwreck locations and permission to investigate them. The MMS is charged with a mandate to manage and protect offshore cultural heritage during the course of mineral extraction on the outer continental shelf. The goal of the strategic partnership is to assist the MMS in identifying, monitoring, and conserving shipwrecks and other offshore cultural heritage sites.

TAMU benefits by providing professors and nautical archaeological graduate students with real world experience, and DMT receives valuable pilot training and equipment testing opportunities.

DMT is entering into a specialized role as an offshore service company that can effectively investigate shipwrecks and other submerged cultural heritage sites, often on short notice. The company has increasingly focused on shipwreck intervention issues for the offshore hydrocarbon exploration and development community. This is an emerging market. As developing technologies facilitate the march into deeper water, more shipwrecks are likely to be discovered. Increased survey and development in near-shore lease blocks are also frequently revealing shipwrecks.

The Mica Discovery
This interdisciplinary cooperation made the Mica shipwreck investigation possible. Explored in July 2002, the Mica wreck represented the deepest archaeological study of a shipwreck in the Gulf of Mexico to date.

It was discovered, quite by accident, on February 16, 2001, 40 miles southeast of the mouth of the Mississippi River. ExxonMobil had recently laid a eight-inch diameter gas pipeline in Mississippi Canyon Lease Block 074. A proposed pipeline route sidescan sonar survey revealed no potential geohazards in the area. Using an ROV, the oil company performed a routine post-installation inspection of the pipeline. While piloting the craft, the operators noticed an object underneath the pipeline, which they quickly identified as a shipwreck. The vessel, approximately 65 feet long, sat upright on the seafloor at a depth of more than 2,650 feet (808m). ExxonMobil graciously provided a large portion of the funding for the investigation.

Nearly all of the shipwrecks studied by nautical archaeologists have been accessible by trained scuba divers. The extreme depth of the Mica shipwreck made this impossible and necessitated the use of both manned and unmanned machines that were capable of withstanding the 1,200 pounds of pressure per square inch.

Equipping the Investigation
The US Navy accepted a proposal to use its NR-1 nuclear research submarine to study the wreck. The submarine was accompanied by a support vessel, the SSV Carolyn Chouest. Additionally, the Naval Oceanographic Office provided a Deep Sea Systems MaxRover work class ROV system and three pilots.

The US Navy's 150-foot nuclear powered NR-1 submarine was launched in 1969 and is capable of diving to 3,000 feet (915m). It has numerous unique features that made it a valuable asset to marine archaeologists and other scientists, the most prominent of which are wheels that allow the vessel to drive on the seafloor.

The NR-1 is equipped with a large manipulator arm and 14 digital video cameras that have zoom, pan, and tilt features. Numerous lights are attached to the hull of the vessel, providing ample illumination in the otherwise pitch-black environment. There is a work module attached to the external hull of the submarine, located immediately in front of the manipulator arm, which contains various tools. These tools are used by the manipulator arm, and include soil coring tubes as well as gripping and cutting devices.

There are three viewports on the lower bow surface of the hull, directly behind the manipulator arm. From this vantage point it is possible to observe the actions of the manipulator arm, as well as search the wreck site without the use of cameras.

For precise maneuvering, the submarine is equipped with two forward and two aft thrusters. These thrusters are diagonally opposed and reversible, which allows for nimble control of the vehicle's position. The thrusters can also be used as a sort of water jet, by directing the column of exhaust water towards areas of the worksite where overburden needed to be removed.

The sub's 238-foot support vessel, the Carolyn Chouest, tows the NR-1 between work areas, and also serves as a floating supply warehouse and provides quarters for the extra crewmembers. During the Mica shipwreck investigation, the scientists were housed on the Carolyn Chouest.

Surveying the Wreck Site
While archaeologists were still planning the investigation, C&C Technologies performed a survey of the shipwreck area using its Hugin AUV. The torpedo-shaped untethered vehicle flew back and forth over the wreck at regular width intervals and at a preset altitude, creating a sonar mosaic of the area. The goal was to define the extent of the wreckage and detect geohazards that might complicate the investigation.

The location of the shipwreck proved less than ideal. It was situated on a bed of fine silt that was continuously discharged from the Mississippi River into the Gulf of Mexico. Particles of sediment constantly rained down of the wreck, which decreased visibility.

While working inside or around the vessel, the sediment that had already been deposited on the wreck was easily disturbed, and could remain suspended for several minutes. The omnipresent currents proved a double-edged sword, as they could swiftly flush out the disturbed sediments, but they made maneuvering and holding position difficult. The deep ocean currents also dictated the search patterns and excavation areas, as it was difficult, if not impossible, to hold a large submarine cross-wise in the current.

A unique hazard of working in the Mica shipwreck area was the location of the gas pipeline, which almost perfectly bisected the wreck amidships. As it was being laid, the pipeline contacted the remains of the vessel, flattening the sides of the hull in the midships section. The pipeline came to rest on the keelson. It was evident that the structural integrity remained strong, as the force of the pipeline caused the bow and stern to lift slightly out of the sediment.

Investigating the Mica
An artifact retrieval system was designed and built at Texas A&M's Offshore Technology Research Center. The system consisted of a square steel mesh-lined box containing 10 individually numbered barrels with doors that prevented retrieved material from escaping. The box also contained an open area in the center, which was designed to hold large pieces of the vessel's metallic sheathing, or structural samples of the vessel, including the sternpost.

This open area was also useful for carrying tools down to the site, including four 3.3-foot scale bars built like sawhorses, which allowed them to sit on top of the unconsolidated sediment, both inside and around the shipwreck. They provided a scale when making photographic and sonar mosaics.

Investigation priorities included making a sonar and digital video/photo mosaic of the site and collecting diagnostic artifacts, including samples of the hull planking, metallic hull sheathing, structural frames, and ceramic objects.

The NR-1 produced sonar and video mosaics of the wreck area prior to disturbing anything at the site. The submarine bottomed out some distance from the wreck and slowly drove along the seafloor until the bow of the submarine was directly over the wreck. Samples of wood and metal were retrieved, including a lead hawse pipe.

On the final day of the mission, the manipulator arm grasped the sternpost of the Mica and carried it towards the surface. However, only 150 feet (46m) below the surface, the external hydraulic system failed and the manipulator arm released the sternpost into the water column. It would never be recovered.

Overcoming Challenges
The archaeological investigation of the Mica shipwreck endured several other mechanical failures, including the loss of the MaxRover ROV. A telemetry problem during a brief test caused the ROV pilots to lose control of the MaxRover, and it drifted into the propellers of the SSV Carolyn Chouest, which was in dynamic positioning (DP) mode, supporting the operations of NR-1. The vehicle was destroyed.

Despite these setbacks, the research team was able to document the wreck site in detail. Based on the shipwreck dimensions, vessel form, and construction style and material, it is probable that the Mica vessel was a fine-lined example of the ubiquitous small coastal merchant schooner that sailed the American coast in the early 19th century.

Identifying the Western Empire
Another example of collaboration between industry and academia occurred in January 2003. A researcher from Texas A&M accompanied DMT during a mission on the Rylan T. Onboard the vessel were a MaxRover ROV and a DeepWorker 2000 manned submersible. The team decided to investigate a shipwreck that had been located during a routine geohazard survey in Mississippi Canyon lease block 195.

After descending to the wreck area, the shipwreck was located at 1,310 feet (400m) using a scanning sonar on the ROV. The nearly intact wooden-hulled sailing ship had a length of 60m and a beam of 12m. The pilots systematically maneuvered the ROV, recording digital video footage of the wreck area. The vessel itself was preserved to a height of 3m in the bow, 3m amidships, and 4m in the stern. There was no evidence of cargo in the remains of the wooden-hulled, iron-framed vessel. The stern of the vessel was filled with deposited sediment, likely concealing and preserving countless artifacts and construction details.

A second ROV dive to the site was carried out, this time in tandem with the DeepWorker 2000. Both vehicles provided the researchers and crew on the Rylan T with high quality digital images of the wreck area.

Based on construction style and overall dimensions, the research team estimated that the vessel was built in the latter half of the 19th century. By reviewing historical records relating to ship losses in the Gulf of Mexico, the team tentatively identified the vessel as the Western Empire.

Built in 1862 in Quebec and home ported in London, the Western Empire was lost on September 18, 1876, en route from Liverpool to New Orleans. The 1,281-ton ship was carrying a load of lumber (explaining the lack of cargo present at the wreck site) when she sprang a leak and foundered. Ten men drowned in the sinking.

WWII Japanese Subs
In late April 2004 researchers from TAMU and ProMare, a non-profit marine research group, led an underwater archaeology mission for the Discovery Channel in an attempt to locate the 24 WWII Japanese submarines scuttled by the Allies near Nagasaki during Operation Road's End in 1946.

The Japanese submarines included the I-402, at the time one of the largest submarines ever built. The enormous submarine was essentially a submerged aircraft carrier, complete with flight deck, and was designed to attack the US mainland. Although the I-402 was not dived on during the brief mission to Japan, the I-58 was located and filmed with an ROV some 663 feet (202m) beneath the waves. The I-58 sank the USS Indianapolis after she had delivered the first atomic bomb to the island of Tinian.

The team plans to return to the site later this year to dive on the remaining targets and document them for posterity. This site is the largest existing collection of Japanese WWII submarines anywhere in the world. During the war, these submarines represented the pinnacle of technology in undersea warfare.v The TAMU team was assisted by many corporations in the survey, including Discovery Channel, Parallax Films, Ixsea Oceano, Kongsberg Simrad, and MacArtney Offshore.

The New Archaeological Oceanography Center
TAMU has long been home to the Nautical Archaeology Program, the Institute of Nautical Archaeology, the Conservation Research Laboratory, and the top-tier Department of Oceanography. The archaeological experience of the first three organizations, coupled with the deep sea capabilities of the latter, create a solid foundation from which to launch a new research program.

The increasing interest in deepwater shipwreck exploration has provided an impetus for the foundation of a new research center, tentatively dubbed the International Archaeological Oceanography Center. The new center is the brainchild of Department of Oceanography Distinguished Professor William R. Bryant, while the nautical archaeological contingent is being led by Dr. Donny Hamilton. Such a center would strive to formulate national and international standards for deepwater nautical archeological discovery and conservation.

Technological Requirements for Deepwater Missions
To date, the Mica investigation represents the deepest archaeologically-oriented study of a shipwreck in the Gulf of Mexico. It was made possible by a cooperative agreement between several federal agencies, the US military, institutions of higher education, and the private sector. This multi-disciplined approach supplied the research team with the expertise and equipment necessary to successfully complete the project. The confluence of technology, expertise, and interest created the necessary climate to proceed with the investigation.

The data gathered about the Mica wreck was as important as the deepwater nautical archaeological research methods that were formulated and tested during the mission. The team learned equally from the successes and failures of the undertaking.

However, more reliable and capable equipment will be necessary to conduct effective research at ever increasing depths. Specific examples of the technology required include underwater vehicles, both tethered and autonomous, that are capable of sending real-time, high-resolution digital video images to archaeologists on the surface support vessel.

In addition to the "eyes" at the site, researchers need tools that can sample and remove the overburden in a controlled fashion. Manipulators with soft grip jaws will be necessary to pick up unconsolidated ferrous artifacts, as well as delicate ceramic objects. Additionally, economical, high-resolution remote sensing equipment will become a necessity to survey large areas of the deep ocean.

The future of deepwater nautical archaeology will remain bright as long as technological development continues to provide researchers with an effective presence at otherwise inaccessible sites. UW

Toby Jones works with Texas A&M University's Nautical Archaeology Program. He can be reached at tobynjones@yahoo.com. Peter Hitchcock and Brett Phaneuf contributed to this article.