This is it!!!, page-97

TD means Total depth & can b revised by the Operator if results r inconclusive from the wireline logs.

Target depths r picked from the seismics (where there is a 'time to depth' conversion algorithm).

Since this is a first crack at a submarine fan in Senegal with no offset wells it becomes challenging getting things right.

They shoot a VSP (vertical seis profile) as they drill through interesting zones.

Simply put a porous/fractured zone will allow sound to travel through it easily compared to either a tight non-porous zone & a zone is filled with fluids (ie gas, oil or water). It's the later that CNE-COP want to know. The response helps in fine tuning their formation tops & allows them to collate more data frm the W/L logs.

Once the logging suites r run over a freshly drilled interval (lets say from 4402m the last casing point to say 4900m) they can calculate the gas-oil, oil-water contacts as well as the respective pressure gradients for the section.

Changeover of fluid type (ie gas, crudeoil, saltwater, drilling mud) with depth in different stacked sands helps in establishing a Oil pressure gradient. If for some reason this is inconclusive an Operator can always direct the geo on the rig to drill deeper, run logs, take fluid samples etc & decipher if they r in a water zone.

Because they r drilling in a Stacked Payzone, each zone will have a variable thickness, porosity & fluid content (G/O/W) & a corresponding pressure gradient is reqd. Hope this helps.

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Metal Storm & Linc,

Thanks for asking the right questions at the conference, much appreciated.

For arguments sake, that 1000 metre quoted is what's referred as 'gross thickness' column. What one needs is 'Net thickness' & confirmation of it's hydrocarbon bearing potential (elevated gas readings, MDT fluid samples), reservoir porosity/permeability data etc. That on its own can b good news if the section has been logged & fluids samples & sent onshore.

If this is the case the JV should notify the findings on completion. I am hoping, as Metalstorm put it last week, that final TD was reached & logged.

That on its own should give sufficient data on any HC's discovered in the well &/or plans to do a production test or just P&A the well for a later day re-entry to do a flowtest & then mobilise the rig 24kms southwest to SNE-1. Look fwd to the update in the nxt 2 days.

Cheers.