This crossplot converts two reference temperatues into a temperatue gradient, which is then used to determine reservoir temperature. Often, only the maximum temperature recorded at total depth is known, along with an assumed mean surface temperature. Since total depth is not usually at reservoir depth, conversion to a gradient is required before determining reservoir temperature.
Reference gradients for Western Canada are also presented as dashed lines on the depth plot, and are defined as follows:
| PRA_NSF_SWA_NEA_NEBC | Peace River Arch, Northern and Southern Foothills, Southwest Alberta, Northeast Alberta, Northeast British Columbia |
| CA_SEA_SASK | Central Alberta, Southeast Alberta, Saskatchewan |
| NWA_XPRA | Northwest Alberta, excluding the Peace River Arch |
Inputs are highlighted in yellow and outputs are in green. Enter the mean surface temperature, along with a temperatue recorded from a reference depth. FInally, enter the true vertical depth of the reservoir.
Outputs incluce reservoir temperature and reservoir temperature gradient. A green dot will be plotted on the gradient curve showing the result, along with two dots representing the reference temperatures (temp at surface and temp at ref depth).