ERS120H5 Lecture Notes - Lecture 21: Water Cycle, Porosity, Metamorphic Rock
Document Summary
97. 5% of the water of the earth is saltwater and it is not a good source of drinking. 2. 5% of the water is the fresh water: from the 2. 5%, 74% is just in glaciers, so the rest 0. 009% is just the safe water to drink. If a gas station was to be made above, there could be a huge amount of contamination in the underground rivers. For drinking, we use the groundwater that is around grains. Unsaturated zone: there is water packed into the soil and saturated zone: just water. Porosity = proportion (%) of material that is made of spaces. Permeability = capacity of water (or oil) to flow through rock interconnectedness of pores: depends on size and arrangement of grains, ex. Sandstones, fractured rocks, unconsolidated sands, unconsolidated gravels: aquitards: low-permeability (does not let water to travel through) Mudstone or shale, unfractured igneous or metamorphic rock: primary porosity: how a sediment is deposited, secondary porosity: the fractured rocks.
