Geology Talk

Wed., Apr. 3, 2019 4:35 p.m. - Wed., Apr. 3, 2019 5:00 p.m.

Location: Classroom Building 130

Presenter: Mr. Morteza Rabiei, Ph.D. Student in the Department of Geology, University of Regina

Topic: Spatial distribution of syn-mineralization hydrothermal fluids along the Patterson Lake Corridor: new constraints on fluid dynamics of the uranium-mineralizing hydrothermal system

Abstract: Unconformity-Related Uranium (URU) deposits in the Athabasca Basin formed from basinal brines under diagenetic-hydrothermal conditions along the intersections between the basal unconformity and basement-rooted faults. Fluid inclusion analyses from uranium deposits in the eastern Athabasca Basin suggests that two types of brines (NaCl-dominated and CaCl2- dominated) were involved during mineralization, with salinities ranging from 25 to 35 wt% NaCl equivalent and the total homogenization temperatures (Th) from 120 to 200 ̊C. Fluid inclusion analyses from the recently discovered basement-hosted uranium deposits in the Patterson Lake Corridor (PLC) in the western Athabasca Basin indicated Th and salinity for the mineralizing fluid comparable with the eastern deposits. The coexistence of liquid-dominated, vapor-dominated and vapor-only fluid inclusions in fluid inclusion assemblages from PLC suggests occurrence of fluid boiling during mineralization, a feature that has also been proposed from uranium deposits in the eastern part of the Athabasca Basin. However, the spatial distribution of NaCl-and CaCl2-dominated fluids and boiling along the Patterson Lake Corridor is not still identified. The purpose of the present study is to evaluate the distribution of boiling, salinity, Ca content and Th of the mineralizing fluids along PLC in different depths and to determine the major controls on this distribution.