Sedimentology and dolomitization in the upper Mississippian Turner Valley carbonates, Quirk Creek, Alberta, Canada.

Date of Award


Degree Type


Degree Name



Civil and Environmental Engineering

First Advisor

Al-Aasm, I. S.






The Mississippian Turner Valley Formation at the Quirk Creek field is composed of a shallowing-upward sequence of shallow platform to restricted lagoon and sabkha carbonates with a thickness of 115 m. Major diagenetic events include: cementation, compaction, silicification, anhydritization, and dolomitization. The most important of all diagenetic events involves a continuous spectrum of early to late dolomitization. Four types or generations of dolomite are identified: microdolomite, patchy dolomite, pervasive matrix dolomite and coarse dolomite. Microdolomite (4-10 $\mu$m) is dense, and locally occurs only in sabkha lithofacies. Patchy dolomite (20 to 200 $\mu$m) floats between skeletal grains, and is distributed along dissolution seams and early stylolites $(\delta\sp{18}$O, $-$0.79 to $-$3.52 per mil PDB). Pervasive matrix dolomite or masssive dolomite (20 to 300 $\mu$m) is the most abundant type of dolomite with predominantly reservoir porosity. Megadolomite (0.5 to 2 mm) consists of coarse, euhedral rhombs and moldic-dolomite. It replaces massive dolomite and crosscuts late stylolites. Megadolomite has higher Fe, Mn, and radiogenic Sr (0.70836 to 0.70875) and lowest $\delta\sp{18}$O $(-$2.12 to $-$6.47 per mil PDB), suggesting formation in a later and deeper burial environment. The reservoir porosity of the Turner Valley Formation is mainly controlled by the degree of dolomitization. The most abundant porosity is presented in carbonates with a dolomite component of 70% to 95%. The potential reserves could be found in these carbonates. (Abstract shortened by UMI.)Dept. of Geology and Geological Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1993 .L844. Source: Masters Abstracts International, Volume: 32-02, page: 0568. Adviser: I. S. Al-Aasm. Thesis (M.Sc.)--University of Windsor (Canada), 1993.