Canadian Shield, approximately lfi) km southeast of Yel-

• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Blachford Lake; Davidson; East Arm; Great Slave Lake; Hearne Channel
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.606.8981; http://rruff.info/doclib/am/vol70/AM70_1127.pdf

lowknife and about 5 km north of the north shore of Great Slave Lake (Fig. l). The locality is centered within the Blachford Lake complex of alkaline to peralkaline affinity. This intrusive complex penetrates Archean metasediments and calc-alkaline granitoid intrusions of the Slave Province to the north, but on its southern side it is closely adjacent to the Aphebian metasediments, metavolcanics and intru-sions of the so-called East Arm or Athapuscow aulacogen of Great Slave Lake (Hoffman et al., 1977). The Blachford Lake complex was first described by. Stockwell (1932) and it was thought to be of Archean age, as are the surrounding host rocks. Later work by Davidson (1972, 1978) and Hoffman et al. (19171, and more recently by Bowring et al. (1984) have confirmed Aphebian ages within the complex; U-Pb zircon study from two compo-nents, the Hearne Channel granite and the Thor Lake sy-enite gave 2175 + l0 and 2094 + l0 m.y. respectively. The Blachford Lake complex The Blachford Lake complex is a relatively large