(Adds background, analyst quote) Aug 30 (Reuters) - Oil and gas...

(Adds background, analyst quote)

Aug 30 (Reuters) - Oil and gas explorer Carnarvon Petroleum (CVN) said on Thursday the Dorado oil find is estimated to hold 171 million barrels of proven and probable light oil reserves, making it the third biggest oil find off Western Australia.

Carnarvon holds a 20 percent stake in the field, with the remainder owned by Quadrant Energy, which is set to be taken over by Santos Ltd (STO) .

Quadrant and Carnarvon revealed the discovery of the oil field earlier this month, describing it as "truly incredible".

Carnarvon said in a statement that the Dorado-1 find consists of a total resource of 283 million barrels of oil equivalent, which includes gas and condensate.

The discovery has a number of significant prospects with further oil potential and planning has begun for future drilling programmes, it said.

"Dorado is amongst the most exciting things to happen for Australian geologists in 20 years. It is amongst the biggest and potentially most valuable oil discoveries in 40 years," Credit Suisse analyst Saul Kavonic said.

Carnarvon made its latest comments in a letter to shareholders, reiterating some details flagged to the market earlier in August.

On Aug. 22, Santos agreed to buy privately held Quadrant for at least $2.15 billion as it embarks on a growth strategy after recently rejecting a takeover offer.