Relative age dating of rocks definition Xxxchats
alkaline - Term pertaining to a highly basic, as opposed to acidic, substance.
For example, hydroxide or carbonate of sodium or potassium.
anorthosite - An igneous rock predominantly composed of plagioclase feldspar (90–100%), and a minimal mafic component (0–10%).
Anorthosites constitute the light-colored areas of the Moon's surface.
arroyo - A steep-sided and flat-bottomed gully in an arid region that is occupied by a stream only intermittently, after rains.
artesian well - A well that penetrates an impermeable layer of rock to reach an aquifer containing water under pressure.
arkose - A variety of sandstone containing abundant feldspar and quartz, frequently in angular, poorly sorted grains.
Geological analysis relies mainly on chemistry, physics and mathematics. a'a' lava - basaltic lava characterized by a rough or rubbly surface composed of broken lava blocks called clinker.
A-horizon - The uppermost layer of a soil, containing organic material and leached minerals.
anthracite - The most highly metamorphosed form of coal, containing 92 to 98 percent of fixed carbon. anticline - A fold of rock layers with a convex shape pointing upwards. aphanitic - An igneous rock in which the matrix grains are too small to be seen with the unaided eye. aquifer - A permeable formation that stores and transmits groundwater in sufficient quantity to supply wells.
archipelago - A group of islands; an expanse of water with scattered islands.