Static Temperature Survey At Newberry Caldera Area (Combs, Et Al., 1999)
Exploration Activity: Static Temperature Survey At Newberry Caldera Area (Combs, Et Al., 1999)
|Exploration Activity Details|
|Location||Newberry Caldera Area|
|Exploration Technique||Static Temperature Survey|
Downhole data collection during this operation was primarily limited to temperature measurements. These temperature logs were taken with Sandia's platinum-resistance-thermometer (PRT) tool which along with a Sandia logging truck remained on-site for the entire project. This instrument uses a simple resistance bridge, with changes in resistance measured from the surface through a four-conductor cable. Since there are no downhole electronics, temperature drift with time is negligible and the PRT temperature measurements are considered a reference standard for this kind of drilling. Logs taken days or weeks after drilling show that temperature gradients in the lower sections of the two slimholes are quite similar, but that the point at which the gradient reaches a relatively constant -8 degreesF/100' is approximately 1000' deeper in TCH 76-15 than in TCH 88-21.
- Jim Combs, John T. Finger, Colin Goranson, Charles E. Hockox Jr., Ronald D. Jacobsen, Gene Polik (1999) Slimhole Handbook- Procedures And Recommendations For Slimhole Drilling And Testing In Geothermal Exploration