I'm currently watching 'Ancient Aliens', a pretty wild show that suggests that there is evidence on Earth for alien contact with ancient civilizations. This particular episode features underwater phenomena. The show describes many megalithic underwater structures discovered by archaeologists around the world. Whether or not these structures were alien bases on Earth (?!), archaeologists have been able to use photographs and videos of the areas to draw conclusions about the age, size, and methods of construction of the structures. Social scientists have used this data to speculate on the uses and symbolic importance of these structures.
The Yonaguni Monument off the coast of Japan.
A 5000 year old city sunk 2000 years ago.
Discovered in 1986.
The ruins cover a 984 X 492 foot area.
Right angles, rock carvings resembling faces, and tunnels built within the pyramid shaped structure suggest the monument was man-made and perhaps a ceremonial site.
Ryall, Julian. "Japan's Ancient Underwater Pyramid Mystifies Scholars". National Geographic News,September 19, 2007.
"Atlantis" off the coast of Cuba.
A 6000 year old city sunk under 2500 feet of water 10,000 years ago.
Discovered in 2000.
The ruins cover a 7.7 square mile area.
Structures resembling roads and pyramids made from cut, smooth, stacked granite-like stones suggest the presence of an ancient civilization. The photographs have been used to compare the structures with oral and written histories of neighboring peoples as well as with modern photographs of Mayan structures in the nearby Yucatan Peninsula.
Posner, Michael. "Evidence of Ancient City Found in Depths off Cuba". Toronto Globe and Mail. December 13, 2001
These research projects prove the ability of photography to assist in data collection and analysis of man made artifacts for Anthropology.