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Geological Cross-section of Southern British Columbia

The Canadian Cordillera is part of one of the world's great mountain systems. Southern British Columbia exemplifies many elements of that system, including "accreted" terranes (blocks of rocks not necessarily formed on or near the continent). Its geological history extends from about 1500 million years ago (Ma) to the present. This includes rifting and sedimentation (until about 500 Ma); collisions bringing accretion of new terranes (200 to 60 Ma), which generated the "great push" to form the Rocky Mountains and an eventual easing from tectonic compression to extension (55 to 40 Ma), allowing deep crustal rocks to be brought to the surface. While the rest of B.C. became tectonically quiescent, oceanic crust continues its relentless push under Vancouver Island and Washington State (subduction), thereby causing large earthquakes and formation of the Garibaldi and Cascade volcanic belts.
Please continue through the poster panels by clicking on the thumbnails.

Map of northern North America showing major geological units Map of the southern Canadian Cordillera showing main geological belts and terrane elements Seismic vibrator trucks ("dancing elephants") transmit short vibration bursts into the deep rock formations Seismic reflection section offshore Vancouver Island and simplified interpretation of it on a lower amplitude display.
Interpreted lithospheric cross section from the Pacific Ocean to the Rocky Mountains Exploring the earth from mountain peaks to their lithospheric roots.

Nature's art: a sheared rock from the middle crust in cross-polarized light

Gravity anomaly map of southern B.C. region with the main geological belts overlain


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