(PMR) Probe Mounted Resistivity

During our EM Development we discovered some interesting side affects of how we can use the information we are using to facilitate our adaptive power management. Using the EM as a basic galvanic PMR (Probe Mounted Resistivity) based on EM telemetry. Our EM transmitter is measuring the gap load resistance to optimize power output. The load resistance is proportional to the length of the BHA below the gap sub and deep rock resistivity. Therefore rock resistivity averaged over the length is being measured all we have to do is send it. This value can be used for geosteering and to compliment gamma. This basic PMR can be built into our EM. Those who have already purchased the system can have it added. We also found It is possible to use additional dual gap sub below the main one. The same EM transmitter output that was connected to lower part of BHA can be also connected to each end of the second gap sub and to the middle part of the first dual gap sub. Amount of current that will flow via this central part into the ground can be measured and will give deep rock resistivity for this short section only. This arrangement is known in the industry as Laterolog 3 or LL3.

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