Abstract:

The structural history of the Flin Flon mining camp has been the subject of numerous studies since the initial discovery of the Flin Flon ore body in 1915, but some elements of these structural studies are incompatible with recent observations and a new seismic survey. A two-year mapping M.Sc. thesis was initiated in 2006 to study rock deformation along the western limb of the Hidden Lake Syncline, where the Flin Flon, Callinan, and 777 VMS deposits are located. This thesis reports on the timing of major rock fabrics and structures in the hinge and western limb areas of the Hidden Lake Syncline and the hinge area of the Beaver Road Anticline.<br/>Seven deformation events are recognized in the Flin Flon mining camp. The Dl Burley Lake structure and NNW-trending D2 Hidden Lake Syncline are bracketed in age by ca. 1890 Ma Flin Flon arc volcanism and emplacement of ca. 1872 Ma intermediate dykes. The ca. 1847 to ca. 1842 Ma Missi Group was deposited on the already-folded volcanic rocks and subsequently displaced by D3 N-trending and D4 E-trending thrust faults. The D3 N-trending thrust faults are constrained by the deposition of the Missi Group and the emplacement of the ca. 1838 Ma Phantom intrusive rocks. The emplacement of the Phantom intrusive rocks is coeval with a regional E-trending D4 thrust faulting and SE-directed stretching. Subsequent non-coaxial tightening of the Hidden Lake Syncline resulted in D5 dextral reactivation of the N-trending thrust faults and the development of a NNW-trending regional foliation. Later D6 deformation resulted in dextral reactivation of the E-trending thrust faults and the development of a NNE-trending foliation. D7 deformation produced N-trending brittle dextral faults.