Weathering & Soils

After rocks are formed, they are weathered when exposed at the surface; this prepares material for transport by erosional processes in the rock cycle two main types of weathering include mechanical (disintegration) and chemical (decomposition) that act together and enhance the effectiveness of each other Mechanical: reduction of rocks to smaller pieces, includes: Frost wedging…

Physical Geology & Plate Tectonics

Geology (study of Earth) is important for energy and natural resources, solving environmental problems, building cities and highways, predicting and protecting against natural disasters like earthquakes, volcanic eruptions, landslides, floods Uniformitarianism: fundamental principle “the present is the key to the past” How long? geologic time is measured in billions of years Where and How? After…

Geologic History Chart

Era Time Millions of Yrs Ago Began — Ended Major Geological Events Major Biological Events Canadian Landforms Created Precambrian (earliest life) 4600      570 – volcanoes erupted, many cycles of mountain building and erosion – 1st single-celled organisms – 1st multi-celled organisms – Canadian Shield formed Paleozoic (ancient life) 570        245 – periods when large parts…