Eternal India Encyclopedia

ARCHAEOLOGY

Eternal India encyclopedia

water photography and excavation and subsequently Srinivas Bandodkar, an expert diver-photographer, trained five qualified archaeologists namely Dr. K. Rajan, Mr P. Gudigar, Mr. Sundaresh, Mr. Sila Tripati, Mr. A.S. Gaur and Mr. Alok Tripathi in underwater exploration and photography. Mr. Y.D. Sharma, Mr. U.S. Shirsat and Mr. Sheikh Ali photographers, received training in diving and underwater photography. The MAC is now equipped for full fledged underwater excavation and retrieval of objects. Geophysical Survey The latest target search techniques involving the use of the Echo Sounder, Mud penetrator or Sub-bottom profiler and side scan sonar for identifying shipwrecks and submerged structures have been adopted by the MAC. The position-fixing of the struc- tures is done with the help of the electronic system namely Motor- ola Miniranger III and from 1990 onwards the Global Position Fixing System (GPS) is used. The Mini Ranger works in C band on a line of sight principle. The mobile station installed temporarily in the Research Vessel transmits microwave signals and the base stations in Dwarakadhish Temple and the lighthouses at Dwaraka and Kacchigadh receive these signals and retransmit them. These signals are in turn received by the station (Mini Ranger) on board the vessel. The time elapsed is converted by the Range Console into distances that are displayed. The position of the ship thus determined is noted as position of the buoy marking the structure or any other archaeological object lying on sea bed. The GPS gives more accurate location using satellite data. For obtaining a plan view of the seabed, geological features and anomalies which may be man-made features, the side scan sonar is used The system is based on the back scattering property of the sea bed. The towed transducers on either side located in the “fish” (fig:38) enclosure transmit and receive sonar signals to and from the seabed. As the transducer moves forward through the water along with the vessel successive strips produce a map of the seabed on either side of the recorded track of the sonar. Because of the angle of the sonar that strikes the objects on the sea bed there will be delay beyond the object before the sound strikes the seabed. This produces a white shadow behind the strong signal allowing the height of the object to be calculated. Sub-bottom profiler is useful in detecting objects and sites buried in compact sediments such as sand. A boomer or sparker should be the energy transmitting

building obstructing the view of the famous temple of Dwar- akadhish at Dwaraka noted for Krishna worship was demolished and to everyone’s surprise a beautiful temple of Vishnu assignable to 9th century A.D. was uncovered. Its roof was damaged by the sea, but the walls, and plinth were preserved by the sand deposit. This discovery acted as an incentive to dig deeper anti trace earlier remains of temples and townships if any. Further excavation brought to light the remains of two more temples. The lower one was datable to 1st century B.C. and the upper one to 2nd-4th century A.D. on the basis of ceramic and numismatic evidence, especially the coins known as Karshapanas. Further digging up to 10m depth exposed debris of a protohisotric settlement in which a distinct pottery known as the Lustrous Red Ware was also found. Similar pottery occurring in Prabhasa (Somnath), another Ma- habharata site on the southern coast of Saurashtra, has been as- signed to the 15th-12th century B.C. The wave-rolled pottery found in the lowest level of the trench at Dwaraka suggested that the proto-historic settlement here was destroyed by the sea. This unambiguous archaeological evidence on shore increased the pos- sibility of finding the remains of the submerged city of Dwaraka of the Mahabharata period in the sea. The oceanographers were also keen to ascertain the cause of submergence of the city. If it was due to a rise in sea level the rate of rise could be determined more accurately on the basis of in situ archaeological finds. Thus began the search for the lost city of Dwaraka. The Department of Science and Technology, and the National Institute of Oceanography came forward to support a project for marine archaeological investiga- tions in Dwaraka and elsewhere. The National Institute of Ocean- ography (NIO) Goa, has been providing the logistic support. The Archaeological Survey of India has been extending financial assis- tance at times. Before the Marine Archaeologist ventures to search for sub- merged cities he must study the bathymetry, geology and topogra- phy of the zone. The NIO scientists have noted a low stand of the sea in the Gulf of Kutch 10,000 years ago. The Marine Archaeo- logical Centre (MAC) in NIO under the direction of S.R. Rao started exploring the Bet Dwaraka island in the Gulf of Kutch because Harivamsa and other texts say that Dwaraka was a Varidurga ‘fortress in water’. It is said to have been built in the sea ‘ Udadhimadhyastham . In the first instance the surf zone of Bet Dwaraka was excavated and simultaneously the Arabian Sea off Dwaraka was also explored from 1982 through 1991. At both the places ancient structures submerged by the sea have been found. Modern Underwater Search Technique Swimline technique had to be adopted-by the diver-archaeolo- gists of MAC for surveying manually an area of 1.5 X 0.5 km seaward of the temple of Sea God (Samudranarayana) at Dwar- aka, and the operation was limited to 15 m depth. In 1989 the side scan sonar, profiler, echo sounder and magneto meter surveys sup- plemented manual and optical surveys for locating the structures and studying the bathymetry. Photographs were taken with Nikonos V underwater camera and video films have been produced by deploying OSPREY underwater T.V. camera. In Bet Dwaraka the visibility is very poor, but slightly better in the Arabian Sea off Dwaraka. Initially fishing trawlers were engaged. From 1987 onward well-equipped modern research vessels Vedhavati and Sea Master were chartered. Ex-navy divers were trained in under-

source. The signals from these sources induce deeper pene- tration. Lower fre- quencies are useful for obtaining better penetration in the sediments of sub- bottom formations and those buried in unconsolidated sedi- ments, but the prob- lem is that the fea- tures are recorded only when the instru- ment passes directly over the object.