There are various estimates of the oil and gas reserves
• Initial interests in the energy potentials were generated by optimistic reports starting from the 1960s, notably the survey conducted under the auspices of the Committee for Coordination of Joint Prospecting for Mineral Resources in Asian Offshore Areas of the Economic Commission for Asia and the Far East (ECAFE) in 1968
• Another optimistic survey was conducted by Ray Geophysical of the US for 11 international oil companies in 1969 and 1970 on eastern and southern Vietnamese coasts