The Indonesian government has invited bids for three shale gas blocks -- Blora, onshore Central and East Java; Batu Ampar in East Kalimantan; and Central Bangkanai, onshore Central and East Kalimantan -- according to a statement on the energy and mines ministry's website Monday.
The bids have to be submitted by December 15, it added.
Indonesia has estimated its shale gas reserves at 574 trillion cubic feet.
The government has identified seven shale gas basins in Indonesia, including Baong, Telisa and Gumai, which are located in Sumatra and believed contain of the biggest reserves of gas; two basins on Java island and two others in Kalimantan.
Indonesia estimates that its shale gas reserves were higher than its potential for coalbed methane and natural gas, which are estimated at 453.3 Tcf and 334.5 Tcf, respectively, according to data from the energy and mines ministry.
The country is looking at exploiting its potential for unconventional energy sources amid declining crude oil output.
