Gravity and magnetotelluric study of the Saskatchewan Elbow impact structure

Graduate Student seminar Friday November 8 at 3:30 pm in rm 155 Geology

Presenter: Ang “Leon” Li, MSc Candidate

Gravity and magnetotelluric study of the Saskatchewan Elbow impact structure

The Elbow structure (50°59'N, 106°43'W) is located in the south-central Saskatchewan on an elbow of the South Saskatchewan River. It was initially discovered using seismic methods by Carter Oil in 1943, which was then verified through drilling by Imperial Oil in 1945. Initially, the structure was interpreted to be formed by either anticlinal or salt tectonism. The Elbow structure is 8 km in diameter and circular in plan, with a central structurally uplifted area of fractured and brecciated target rocks surrounded by a ring depression. The impact occurred between 370 to 420 million years ago during the Devonian period, strata through Upper Cretaceous to Upper Devonian are disturbed by the impact event. From September to October 2019, both gravity and white-band magnetotelluric (MT) survey were conducted over the diameter of the impact. A total of 86 gravity station data were collected across 10 km distance to delineate the lateral structure of the crater. Frequency band from 10 kHz to 1000 s was used to collect MT signals and study the vertical depth of the impact.