The landscape and architecture, or Geoscape, of southern Vancouver Island is the product of a wide variety of natural processes acting over some 370 million years. Several episodes of volcanism, erosion, sediment accumulation and crustal movement have provided one of the world's best laboratories for the study of the effects of plate tectonics. By virtue of its position beside an actively moving ocean floor throughout the past 170 million years, Vancouver Island is an assembly of different pieces of the Earth's crust, all of which originated at different times, at different places and under different circumstances. The fact that earthquakes are a common occurrence in this region is dramatic evidence that crustal movement is continuing today.
Added to these tectonic processes are the effects of glaciation. As recently as 15,000 years ago, 1500 metres of ice covered most of the island. Fiords such as Saanich and Alberni inlets as well as the straits of Georgia and Juan de Fuca owe their existence in part, to the sculpting power of ice.
The cumulative effect of these island-forming processes includes the beautiful scenery that surrounds us as well as the formation of important mineral deposits and groundwater reservoirs. It is these and other natural legacies of the geological history of southern Vancouver Island that need our constant stewardship and care. Moreover, the probability that significantly large earthquakes may occur requires thoughtful attention not only to safe building design and construction but also to other matters affecting public safety.
The Geology of Southern Vancouver Island: A Field Guide., C.J. Yorath and H.W. Nasmith. Orca Book Publishers. 1995.
Geology of Victoria. J.E. Muller. Geological Survey of Canada, Map 1553A. Scale 1:100,000. 1983.
Relative Earthquake Hazard Map of Greater Victoria, Showing Areas Susceptible To Amplification of Ground Motion, Liquifaction and Earthquake-Induced Slope Instability. P.A. Monahan, V.M. Levson, E.J. McQuarrie, S.M. Bean, P. Henderson and A. Sy. B.C. Ministry of Energy and Mines, Geological Survey Branch Geoscience Map 2000-1, 200
