ANKLESHWAR (RU: Анклешвар) is the oil and gas field within India (Gujarat state), at the 16 kilometres to the south-east from the Bharuch city. It belongs to the Cambay oil-gas-bearing basin. It has been discovered in 1960, and is operated since 1963. The initial industrial oil reserves are 50 million tonnes. It is confined to the local uplift with amplitude of 240 metres, with the size of 12x3 kilometres. There are productive the Miocene, Eocene, and Paleocene reservoirs at the depths of 330-1590 metres.

The reservoirs are structural and combined. The collectors are sandy, the open porosity is 15-21%, the permeability is 100-925 millidarcies. The initial reservoir pressure is 10 megapascals, the temperature is 78-80 degrees Celsius. The density is 790 kilograms per cubic metre, the viscosity is 1.24-1.51 centipoises. The composition of the oil (%) is: 7.4-9.1 of paraffins, 2.1-3.3 of resins, 0.08-0.2 of asphaltenes. The composition of the gases (%) is: 41.8-81.4 of CH4; 10.6-22.3 of C2H6; 7.5-37.1 of C3H8 + higher; 0.1-1.1 of CO2. The mode of operation is elastic water-pressured, there is used flooding. The annual extraction is 1.9 million tonnes (1979), the accumulated extraction (by 1979) is 38.8 million tonnes. It is developed by the "Oil and Natural Gas Commission" company.