Petrophysical Evaluation of Gas Hydrate Formations

Gas hydrates are recognized as a massive source of fossil fuel that could be far in excess of conventional hydrocarbon<br>resources. The evaluation of formations that contain gas hydrates is therefore receiving renewed emphasis through<br>contemporary petrophysical technology. A key factor is the use of logging-while-drilling (LWD) to sense hydrate-bearing<br>intervals before drilling-induced thermal invasion and thence hydrate dissociation take hold. Recent advances in LWD<br>technology have brought most of the potentially diagnostic tools onto the drill string, so there is little disadvantage in not<br>having a wireline database. Moreover, modern tools have a sharper spatial resolution and a greater capability for differential<br>depths of investigation.