Replies to post #2117 on Empire Energy Corporation Intl. (fka EEGC)

[irtamos]

This makes me a little bit upset :


Letter to the Editor, ‘The Mercury’ 2 January 2003
(Dr) Gareth Cooper (Structural and Petroleum Geologist), Launceston


“Oils ain’t necessarily oils” (Editor’s heading)

It is correct that drilling in the Tasmanian Basin has not to date delivered any oil and that statements published in ‘The Examiner’ and ‘The Mercury’ (December 21) may be somewhat premature.

In fact, of the 42 oil exploration wells drilled in onshore Tasmania since 1915, none have ever recovered a single drop of oil.

This may not necessarily be the case for offshore wells where the Jurassic-Cretaceous succession is still preserved.

The “oil” from the Hunterston-1 well, mentioned in the article, may indicate that hydrocarbons may have been generated in the Tasmanian Basin at some point in the geologic past (which has been known for many years).

However, this should be viewed in context. Firstly there is still no definitive evidence that any “live” oil (active and recoverable oil) is present at Hunterston-1, as drilling at the site has not involved industry-standard equipment, namely the use of wire-line logs (neutronporosity), a modern gas chromatograph, or a perforating drill-stem test (DST).

Secondly, the three samples sent to Adelaide for analysis, and which have been reported as containing oil, were subject to sediment solvent-extract of organic matter (EOM). This type of analysis extracts microscopic amounts of hydrocarbon and may not indicate whether the oil is “live” or residual (dead oil).

The success rate for wild-cat hydrocarbon exploration wells in Australia is less than one in 10. The remaining nine in 10 dry or failed wells often contain some form of hydrocarbon “show” as a result of a residual or dead oil column. However, these wells never flow oil. In the case reported, only a chamber sample from a DST can provide definitive evidence of live oil in the absence of wire-log data.

Thirdly, I was more than surprised by the astronomical volumes of hydrocarbons reported in the article (4.9 billion barrels), especially given that no oil has been produced.

This volume is 10 times greater than the amount of oil and condensate recovered to date from the 27 producing oil fields of the offshore Barrow Sub-basin in Western Australia (Australia’s most prolific oil-producing basin) – insignificant compared to the reported Tasmanian “discovery”.

It is standard to base such volumetric hydrocarbon calculations on a probabilistic risking model using detailed 3D and 2D seismic mapping of the reservoir closure.

Given the paucity of data, it may be difficult to understand how probable and proven reserves may be derived let alone in the fantastic volumes reported in the article.

As with all important issues, I urge all interested parties to continue to seek detailed analyses of all data, and perhaps some independent professional advice where necessary.