Setting:

In the summer of 2011 Geoscience BC, the Horn River Basin (HRB) Producers Group and four participating gas producing companies needed to locate near surface water sources to use for fracturing rock to release trapped gas. The HRB covers over 2 million acres and since ground surveys were not feasible to cover the area quickly and effectively the group decided to assess airborne geophysical techniques. The criteria included an analysis of airborne’s ability to identify and map sources of near surface groundwater (less than 200 m), locate buried channels and delineate overburden stratigraphy.

Solution:

The SkyTEM method was selected to collect data over four strategic areas and the SkyTEM304 system as deployed. The SkyTEM 304 was specifically developed to map aquifers and is capable of mapping to depths of up to 300-350 m.

Findings:

Results of the survey will be made public by Geoscience BC in early 2012 however the four gas producing companies have started to drill targets identified by the SkyTEM data. One producer states that drilling a near surface target produced an artesian well. Suspected aggregate deposits have been interpreted as well from the data. Below is a vertical profile of an area in Denmark showing paleochannels mapped to a depth of almost 200 m. These channels are similar in depth and composition as those being studied in the HRB.

Conclusions:

Airborne geophysics is a quick way to collect data and characterize a large area without the need to put people and vehicles on the ground. SkyTEM’s accurate high resolution data set can be interpreted for different targets and in this case the targets were paleochannels at different depths and near or on-surface aggregate sources. Information on Geosciences work in the HRB and a status report of the SkyTEM survey can be found at: Geoscience BC and SkyTEM survey.

SkyTEM was given a demanding schedule for completion of all survey flying. The company completed all work slightly ahead of schedule and delivered preliminary data on a daily basis.