Ann: Dorado-2 Drilling Update, page-28

u r right abt change in Res properties. Easy to pick when there is water, oil in the reservoir.

While drilling the MWD tool has a gamma & res tool which picks up change in any sand/ shale ratio & corresponding fluid over any interval as they drill thro'. This is then verified by running various suites of WL logs.

One such tool deployed in that run is an MDT tool (or Saturn probe). This tool is manouvered along Zones of interest & its probes take a jab into the rock to fill up the onboard Sample Chamber/ tank. This is recovered when the tool is winched back to surface.

At the same time when taking the representative fluid jab, this tool is also recording the Pressure readings (in psi) via its Pressure pads & the mobility/ drawdown time for the jab (e.g: 500cc filled up in xx minutes). This is basically termed as a mini-DST by some service providers. However, the real DST is much different & is an extended version over many days over say 10-20 metres or multiple tests over isolated sections. Hope this helps.