The area under discussion in this report comprises a small section in the heart of the Flin Flon Mining District, nearby the town of Flin Flon and the Hudson Bay Mining and Smelting Company. These are located approximately on the Manitoba-Saskatchewan boundary at latitude 54o 45'. Communication is by a branch line of the Canadian National Railway from The Pas, Manitoba, where a Recording Office is located. The Sherritt-Gordon Copper Mine is reached by a spur from this Flin Flon line. The area of the volcanic centers occurs on the north-west side of Flin Flon Lake and is therefore on the Saskatchewan side of the boundary. This territory has been extensively burnt, thus making detailed geological work possible. From the lake the larger of the volcanic centers, termed the Road Volcanic Center, is clearly visible, standing out above the neighboring formations. This center is reached within a few minutes from Flin Flon Lake, by a portage trail running to a lake further west. Approaching the center this way, it rises up quite abruptly from a low grassy area. It borders are equally distinct on the west and north, but on the south it interfingers with many types of explosive breccias, tuffs and flows. The Club Lake Volcanic center lies due north of the Road Volcanic center, and south of Club Lake. Its western border rises up very abruptly but elsewhere it interfingers with explosive materials and flows. The area of these volcanic centers affords about the most fascinating geology that one could conceive. A remarkable amount of data which dovetail to an amazing degree tend to prove that a major granitic intrusion reached to within a few hundred feet of the surface and then broke through a series of lavas and sediments to form two or more centers of volcanic activity. About these is a series of explosive breccias, tuffs and flows which in their field relationships and in their lithology are clearly related not only to the necks of the volcanic centers but also to the granitic intrusive....