Wind, Glaciers, and Groundwater

• WIND is a type of erosion that occurs especially in dry areas.
• Wind can erode by picking up and carrying loose particles and dust away, a process known as deflation.
• Wind can also erode when these flying particles strike the land and break off more particles, a process known as abrasion.
• A sandy clay unit is an example of an aquitard.
• Massive compact rock without any fracture is an aquifuge.
• Clay is an example of an aquiclude.
• Unconsolidated deposits of sand and gravel form a good aquifer.
• Suspension is a process that moves fine particles (less than 0.1 mm) of dirt and dust over long distances.
• Saltation is a process that moves soil particles (0.1 –0.5 mm) across a surface by a series of short bounces along the surface of the ground, and dislodging additional particles with each impact.
• Creep occurs when larger soil particles (0.5–1mm) slide and roll over an area and meet particles that have been through saltation.
• Glaciers are a large, long-lasting mass of ice, formed on land, that moves under its own weight.
• Glaciers can develop any place where, over a period of years, more snow accumulates than melts away or is otherwise lost.
• The velocity of a glacier is lowest near the base and where it is in contact with valley walls; but the velocity is highest near the top center of the glacier.
• Soil water zone lies close to the ground surface, is held in the pore spaces between particles of soil, and is the water that is immediately available to plants.
• The deeper parts of unconfined aquifers are usually more saturated since gravity causes water to flow downward.
• Saturated zone is classified into 4 categories: Aquifer, Aquiclude, Aquifuge, Aquitard.
• An aquifer is a layer of porous substrate that contains and transmits groundwater, and can be extracted using a water well.
• The soil water zone can be removed by air drying or by plant absorption, but cannot be removed by gravity.
• Intermediate zone is the layer that is available next to the soil water zone, lies in between the soil water zone and the capillary zone, and the soil moisture in the zone of aeration is of importance in agricultural practices and irrigation engineering.
• Unconfined aquifers are sometimes also called water table or phreatic aquifers, because their upper boundary is the water table.
• Capillary zone is the subsurface layer in which groundwater seeps up from a water table by capillary action to fill pores, with pores at the base of the capillary fringe filled with water due to tension saturation.
• An aquiclude is a solid, impermeable area underlying or overlying an aquifer, which if it overlies the aquifer, could cause it to become a confined aquifer.
• An aquitard is a bed of low permeability adjacent to an aquifer, which may serve as a storage unit for groundwater, although it does not yield water readily.
• An aquifuge is an impermeable body of rock which contains no interconnected openings and therefore neither absorbs nor transmits water.
• A confined aquifer is a water-bearing subsurface stratum that is bounded above and below by formations of impermeable, or relatively impermeable soil or rock, also known as an artesian aquifer.
• Glaciers and frozen sea ice are part of a subsystem of the hydrosphere known as the cryosphere.
• The cryosphere includes those portions of Earth's surface where water is in solid form, including sea ice, lake ice, river ice, snow cover, glaciers, ice caps, ice sheets, and frozen ground (which includes permafrost).
• Alpine glaciation is found in mountainous regions.
• Continental glaciation exists where a large part of a continent (thousands of square kilometers) is covered by glacial ice.
• Valley glacier is a glacier that is confined to a valley and flows from a higher to a lower elevation.
• Geological features created by glaciers include Arêtes, Cirque, Horn, and Moraine.
• Material which is carried along by the ice is called moraine.
• Large stones which are dropped as the ice melts are called erratics.
• Till: The unsorted and unlayered rock debris carried or deposited by a glacier is called till.
• Meteoric water: Meteoric water is rain droplets that seep down into spaces between the rocks and becomes the part of the water table.
• Medial moraine: Where tributary glaciers come together, the adjacent lateral moraines join and are carried downglacier as a single long ridge of till known as a medial moraine.
• Groundwater: Groundwater is the water found underground, in the cracks and spaces, in soil, sand and rocks.
• End moraine: If the terminus remains stationary for a few years or advances, a distinct end moraine, a ridge of till, piles up along the front edge of the ice.
• Sometimes, especially during times of high rainfall, these pore spaces are filled with water.
• The aeration zone (unsaturated zone) has 3 sub-zones: Soil water zone, Intermediate zone, and Capillary fringe.