Overview of the Geological Evolution of the Canadian Shield in the Andrew Lake Area Based on New Field and Isotope Data, Northeastern Alberta (NTS 74M/16 )

To update the geological knowledge and better assess the mineral potential of the Canadian Shield in northeastern Alberta (Alberta shield), Alberta Geological Survey (AGS) re-examined selected outcrops and previous exploration sites of the 1960s and 1970s near Andrew Lake.

In summer 2006, AGS carried out geological mapping and sampling near Andrew and Waugh lakes to better understand the geological context and key lithological contacts with direct metallogenic and cartographic implications for the Canadian Shield within Alberta.

The objective was to review the general geology of the Andrew Lake area, based on the original geological reports of J.D. Godfrey and the updated Geological Survey of Canada Map 1953A, and to examine the evidence for existing tectonic interpretations with direct cartographic implications for the Alberta shield.

This report includes a summary of previous work, brief descriptions of the main map units, a re-evaluation of previous isotope data, new geochemical and isotope data, and a discussion of their significance. It also includes preliminary results and recognizes that well-documented conclusions on the geological evolution of the Andrew Lake area require further detailed and systematic field and analytical work. Systematic sampling of several varieties of controversial rocks for geochemical and multisystem isotope analysis may shed new light on their origin and evolution.

Based upon the review of the current state of knowledge and new field and analytical data, the author recommends that the informal term "complex" replace the formal stratigraphic rank of "group."