spatial distribution
The pattern of where something is located across an area: clustered, scattered or in a line.
physiographic region
A large area with similar landforms and rock, such as the Canadian Shield or the Interior Plains.
igneous rock
Rock formed when melted rock (magma or lava) cools and hardens, such as granite.
metamorphic rock
Rock changed by great heat and pressure deep underground, such as gneiss.
sedimentary rock
Rock formed from layers of sediment (sand, mud, shells, plant remains) pressed together, such as sandstone and shale. Fossil fuels form in sedimentary rock.
ore
Rock that contains enough of a valuable mineral to be mined at a profit.
growing season
The number of days between the last spring frost and the first fall frost, when crops can grow.
continental shelf
The shallow, gently sloping sea floor at the edge of a continent, often rich in fish.