This paper examines underwater archaeology in the U.S. The paper discusses excavation techniques, tools and technology and also explores the Clovis theory. The paper also reviews findings at several submerged North American prehistoric archeological sites.
Underwater survey and excavation are typically more expensive and logistically more complex than comparable terrestrial projects. Underwater conditions involve more variability from site to site, and even from hour to hour at the same site. All survey and excavation work is constrained by safety factors; in general the deeper the site, the less time that a scuba diver can remain at that depth. Other factors that are frequently less than ideal include water currents, temperature, and visibility (Merwin, Lynch, and Robinson, 42).
Nonetheless, the potential to recover significant archaeological data outweighs the disadvantages of working underwater. In fact, underwater sites may allow for the preservation of organic materials such as bone, wood, leather, textiles and basketry, which infrequently survive in the acidic, sandy soils that are typical of most of the dry coastal plain in Eastern North America. The identification of favorable excavation sites is achieved with the use of remote sensing techniques: looking at the sea floor with side-scan sonar or multibeam swath bathymetry, as well as looking beneath the sea floor with sub-bottom or other seismic profiling. Once promising areas are identified, they can be more closely examined using coring, dredging, remotely-operated vehicles outfitted with video cameras and other equipment, as well as by scuba diver inspection (Merwin, Lynch, and Robinson, 42).
Underwater archaeology was not considered the typical research venue for North American prehistoric archaeologists, but the field has been expanding. Some problems of prehistory in certain regions can only be addressed by underwater research, such as when and where people began to adapt to coastal environments and use boats. The field was pioneered in the 1960s by marine geologists K.O. Emery and R.L. Edwards who were among the first to suggest that Paleoindian and Archaic period sites might be sought on the continental shelf of eastern North America. Their research occurred at a time when the North American archaeological community was focused on terrestrial issues, so their findings drew little immediate reaction (Faught, 273).
Initial investigations of marine submerged sites occurred around the country during the 1980s. Ground stone and other artifacts of the middle Holocene were recovered from underwater sites in southern California. By the 1990s, methods of finding, testing, and interpreting submerged prehistoric sites appeared in an increasing number of publications (Faught, p.273).
A problem in eastern North America involving underwater archaeology is the determination of when and where people of Clovis ancestry arrived at the Younger Dryas paleo-coastline near modern day Florida, either by way of inland routes to the continental margins, or from coastal routes, migrating inland. Whether the coast-first or coast-later model is valid, determining if there are early Clovis sites offshore or if there were only later Paleoindian and Early Archaic remains requires the excavation of submerged prehistoric sites (Faught, p.274).
At one time the prevalent archaeological theory regarding the Paleoindian period described bands of hunters arriving on the North American continent around 13,000 B.C. Some believe that Clovis hunters crossed a land bridge between eastern Siberia and Alaska that was created during the Late Pleistocene by the formation of continent-sized glaciers. These glaciers drew water from the oceans, thereby lowering sea levels by approximately 120 meters. Supporters of this theory believe that glaciers also subsequently blocked the immigrants from moving into the remainder of the North American continent until about 12,000 B.C. (Anderson and Faught, n. pag.).
Archaeological evidence that argues for the presence of these early Paleoindian bands consists of long, fluted chipped stone projectile points believed to be used for spear points. The points take their name from the Clovis, New Mexico archaeological site where the point type was first documented in 1932 and associated with the Late Pleistocene. The Paleoindians appear to have occupied a large portion of the North American continent and the Southeast in the centuries following 10,000 B.C (Anderson and Faught, n. pag.).
More recent findings have cast doubt on the Clovis theory, questioning whether the big game hunters arrived from the north. According to Alejandra Duk-Rodkin, a researcher with the Geological Survey of Canada who studied the history of the river systems that drained the melting glaciers, the route between them was impassable until after the Clovis culture was already flourishing far to the south ("Florida's First People," n.pag.).
Nor has any satisfactory theory been proposed to explain why, if Clovis hunters came from Asia, there have not been reports of finding fluted points in northeast Asia. Nor does the Clovis theory account for the fact that significantly more fluted points have been found east of the Mississippi than west of it. This finding, along with DNA studies showing some North American ethnic groups to have European lineage, has caused archaeologists to question whether Clovis origins may be European, not Asian ("Florida's First People," n.pag.). Subsequent research has been directed at finding out if the first people to reach North America may have come by boat from Europe.
Beginning in 1960, archaeologists conducted studies of river basins and statewide sites that yielded Paleoindian point finds and site distributions throughout the Southeast. These studies contributed to improved sequencing of point types as well as efforts to reconstruct Paleoindian cultural activities. Underwater and terrestrial excavations of Paleoindian sites, along with improvements in dating techniques and studies of the distribution of Paleoindian point types, resulted in archaeologists developing new models for Paleoindian occupation of the Southeast (Anderson and Faught, n. pag.).
Archaeologists have long pondered the origins of North American first people, debating when they first arrived, where they came from, and where they went. In their quest for answers, archeologists have undertaken a number of underwater excavations. Michael Faught, assistant professor of anthropology at Florida State University, searched out sites on the Gulf floor that he believed were visited by ancestors of the Clovis people. In 2003, Faught's team found what may be a 12,000-year-old projectile point dating back to the Suwanee era. Faught believed the Gulf floor sites could provide answers about when people began to live in Florida. Those excavation sites may also shed light on whether people came ashore at the Gulf Coast and then moved inland, or whether they traveled from the interior to the coast ("Florida's First People," n.pag.).
Florida's geography has changed significantly since the time when hunters of the late Paleo-Indian and Early Archaic periods lived along the Aucilla River in the Big Bend region. At that time North Florida extended about 85 miles farther out into the Gulf. But a period of global warming began about 17,000 years ago and continued for the next 10,000 years which melted glaciers and flooded almost half of what was Florida. Rivers like the Aucilla, Ochlocknee and St. Marks that flow into Apalachee Bay today formerly had ancient segments that are currently submerged on the continental shelf. Water covers the sites that archaeologists like Faught and his colleagues want to find ("Florida's First People," n.pag.).
Starting in 1997, Faught operated his underwater archaeology program. Faught and his team used specialized equipment to search the area that they identified as a likely place to find artifacts. They mapped a square kilometer of the floor of Apalachee Bay using side-scan sonar, and selected 35 sites for investigation. Divers recovered more than 4,000 pieces of chipped stones along with several hundred bone fragments from Pleistocene animals, including a giant sloth, horse, and mastodon ("Florida's First People," n.pag.).
Based on these findings, Faught concluded that there were two periods of occupation along the submerged banks of the Aucilla River. The first dates back to 12,000 years ago when the sea was 85 miles away, and people worked with wood and stone and lived off deer and freshwater fish. The second period of occupation occurred 8,000 years ago, when the landscape became a coastal habitat. People of that time collected oysters in the tidal creeks of the river mouth. Faught wanted to research even farther back, looking for artifacts that pre-dated the Clovis era. He believed that the farther out into the Gulf that he excavated, the farther back in time he would travel. Faught believed his work would clarify the debate about when the first humans arrived in the Americas ("Florida's First People," n.pag.).
According to Faught, the traditional theory that all of the prehistoric settlers of America were people who had crossed a land bridge from Asia into Alaska was not consistent with the artifacts discovered to date. "We don't see the artifacts of early Clovis culture in the far Northwest or Alaska… the best evidence of Paleo-Indian continuity through time anywhere in the western hemisphere is in the southeast," Faught argued ("Florida's First People, 2004, n. pag.). He also contended that artifacts they recovered from 15 feet of water were not washed downstream by the river, pushed out…