Alaska Pipeline Project (APP) Transect of Shallow Boreholes
These boreholes were part of the Alaska Pipeline Project (APP), TransCanada and ExxonMobil, that drilled over 120 boreholes in a transect from the Alaska / Canada border near Tok, AK to Prudhoe Bay, AK between 2009 and 2012. Temperature in the boreholes was then measured a few times by APP to determine the temperature envelope. Rather than capping the boreholes they were donated to GIPL and we are instrumenting a subset of them over the next few years.
Project Site Map
After instrumentation, the sites are visited once per year to collect data.
These sites are equipped with two data loggers from Onset Comp. Corp. Each logger has 4 temperature sensors, for a total of 8 (typically at 0.03, 0.5, 1, 1.5, 2, 4, 6, and 9 m). Due to storage space and limited battery life, these loggers are typically programmed to record data every few hours. Temperature is measured using a single thermistor that is taped together with other thermistors to form a sort of thermistor cable that is installed in the borehole with the exception of the surface (3 cm) depth that is installed directly in the ground adjacent to the borehole. After ice-bath calibration the accuracy of these sensors is better than ±0.10°C.