Drop gyro with GR

15 July 2015 Hi folks

At a DWOP yesterday, the topic of "drop-gyro with GR" came up.

Fixing borehole uncertainty and linking it with formation tops is critical, so the gyro needs to be run with GR.

Max. deviation is 85 degrees, so the original options were tractors and pipe-conveyed logging. Then the idea of dropping the gyro came up, with a "pump-down assist" feature.

The problem is that we've been told that the GR "sonde" is not robust enough to withstand dropping/impact of landing on the profile.

So, the question is:

• Do you know of suitably robust GR (or alternative measurement devices to tie-in to Formation tops")?
• If you've run them, what best practice and lessons can you share with us?

Other information:

• BHT is 230-250 deg F (not particularly hot)
• Depth is 12,000 ft

Many thanks

Dave

8 Answer(s)

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