| Title | Temperature Changes with Time in the Slotted Interval of a Deep, Shut-In Geothermal Well near Thermal Equilibrium: East Mesa Well 31-1, Imperial County, California, 1977-1982 |
|---|---|
| Authors | Diment, William H.; Urban, Thomas C. |
| Year | 1982 |
| Conference | Geothermal Resources Council Transactions |
| Keywords | Drilling; Exploration; USA; California; Imperial Valley; East Mesa Well; Temperature Logs; Wellhead; Casing; Anomalies; Temperature Gradient; Conductivity; Casing; Geothermal Gradient |
| Abstract | Five precision temperature logs were obtained over a five year period (1977-1982) beginning three years after drilling and one year after last significant testing in East Mesa well 31-1. A sensitivity of measurement of 0.0001° was maintained to the bottom of the well (165°C, 180 bars). Useable precision was limited by convective motions within the hole (0.01-0.3°C depending on ambient geothermal gradient) fluid leakage through the lubricator at the well head (4 bars) and occasionally by electrical or electronic noise. Comparison of these continuous logs indicates a general warming in and just above the slotted interval (1647-1877 m) which is attributed to flow into the lower levels of the slotted interval and up the casing and out into the permeable zones at higher levels. Some flow continued upward through an uncemented interval of the annulus between casing and hole and out into the formation where it is blocked by cement. Some points of entrance or egress of fluid are marked by small, sharp temperature anomalies which have persisted over the 5 year period. Apparently, the uncemented part o the annulus has partly filled in, and flow into the bottom of slotted interval has increased (1978-1982). Both of these changes may have been induced by the nearby Imperial Valley earthquake of 10.15.79, or by the production or testing of nearby wells. |