title of the thesis - Department of Geology - Queen's University

Figure 3.14: Sample fault plane solutions for macroseismic events corresponding to
the 7400 Level, January – December 2007. Grey quadrants represent compression and
white quadrants represent dilatation. Each triangle represents the polarity of the first
arrival at a sensor.
3.3.1.2 Fault plane solutions for microseismic events
Fault plane solutions were generated for 196 microseismic events during the 2006 time period,
belonging to the 7400 and 7530 Levels. Solution planes and axes for individual events can be
found in Appendix C. The chosen events have low location errors (less than 30 feet), good
statistical fits for fault planes as well as adequate visual fits. Fault plane solutions have an average
fit of 77%. Fault plane solutions and calculated fits were generated using the program VFps by
the Engineering Seismology Group. Discarded events include those that do not fit a doublecouple
solution, events with poor focal sphere coverage and events with poor first polarity picks.
P-axis, T-axis and B-axis attitudes (as shown on Fig. 3.11) plotted on a lower hemisphere
stereonet form broad clusters (Fig. 3.15). Classification of failure modes using the focal
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