Preliminary Tomography From the Batholith Passive Source Project

The primary goal of the Continental Dynamics `Batholith' project is to constrain the petrogenesis of the Eocene Coast Mountain Batholith and determine the fate of the residual mass complementary to the massive Eocene granitic melt distillation event. The passive source component of this project was mobilized in June of 2005 and will be demobilized in September of 2006. Currently, 44 broadband seismic sites are being operated along two 260 km long lines that straddle the Coast Mountain Batholith at the latitude of the Queen Charlotte Islands. The northern line is aligned approximately NE-SW and starts in Douglas Channel, runs through Kitimat, and north to Hazelton. The southern line is approximately E-W, starts in Burke Channel, runs through Bella Coola and eastward to Anahim Lake. The two lines are separated by 200-300 km in the Coast Mountains Batholith. These high station density (14 km station spacing) line arrays will permit well resolved tomographic P- and S- wave body wave images. Preliminary tomographic results from the full 14 month dataset will be presented for both the northern and southern lines.