Unit 2 Ch 7 Vocab Flashcards
Neptunism
the obsolete theory that all rocks of Earth’s crust were deposit from, or crystallized out of; water
Plutonism
the obsolete theory that the rocks of Earth’s crust formed by solidification of a molten material or were heated
atomic number
the total number of protons in an atom
ion
an atom or molecule that possesses an electrical charge
cation
ion with a positive charge
anion
ion with a negative charge
covalent bonding
union formed when two or more atoms mutually share electrons
ionic bonding
molecular bond formed when two oppositely charged atoms (ions) attract
silicates
a substance that contains silica as part of its chemical formula
crystal form
the arrangement of various faces on a crystal in a definite geometric relationship to one another
cleavage
the tendency of a mineral to break along planes of weak bonding
hardness
resistance of a mineral to scratching; Mohs scale - 10 minerals
color
used to describe minerals
luster
appearance taken on by a mineral in reflected light
streak
color of a pulverized substance; a useful property for mineral identification
absolute hardness scale
denotes hardness based on how much pressure must be applied to a diamond point moved across a mineral before a scratch appears
igneous rock
a rock formed by the crystallization of magma or lava
lava
magma that reaches the ground surface
plutonic igneous rocks
igneous rock formed at great depth; cool slowly far below surface; large crystals
texture
The general physical appearance of rocks. The size, shape, and arrangement of component minerals in sedimentary rocks determine the texture. In igneous rocks and metamorphic rocks, the crystallinity and fabric of the minerals are major determinants of texture.
beds or strata
strata: parallel layers of sedimentary rock
bed: the smallest division of a series of layered rocks, marked by a well-defined divisional plane from its neighbors below and above
volcanic igneous rocks
small grain size; cool rapidly at surface; small crystals
clastic sedimentary rocks
a sedimentary rock made of fragments of preexisting rock
chemical sedimentary rocks
the processes by which the internal structure of a mineral is altered by the removal or addition of elements
biochemical sedimentary rocks
a sedimentary rock made by or from organic matter
weathering
the group of processes that change rock at or near Earth’s surface
transportation
movement of materials from one location to another
erosion
the physical removal of rock by an agent such as running water, glacial ice, or wind
lithification
the process by which unconsolidated sediments become consolidated rocks
crystal settling
during the crystallization of magma, the earlier-formed minerals are denser than the liquid portion and settle to the bottom of the magma chamber
metamorphic rock
a rock produced by metamorphism
contact metamorphism
changes in rock caused by the hear from a nearby magma body
regional metamorphism
the name applied to those metamorphic alterations that affect rocks over large areas and are indicative of widespread environmental changes rather than localized deformation or magmatism
foliation
planes of minerals formed in response to stress; a feature of many metamorphic rocks
rock cycle
a sequence of processes and products that relates each rock type to the others and that describes rocks as continuously forming from preexisting rocks
mineral resource
all discovered and undiscovered deposits of a useful mineral that can be extracted now or at some time in the future
hydrothermal mineral deposits
mineral deposits formed when heated water circulates through rock pores or other openings
magmatic mineral deposits
mineral deposits formed when minerals become concentrated as magma cools and solidifies
residual mineral deposits
mineral deposit formed from the leaching of soil by water
placer deposits
found in present-day streams or in ancient stream deposits; represent a natural recycling of older mineral deposits
magma
molten rock that may contain dissolved gases as well as some solid minerals
metamorphism
the effects of increasing temperature, pressure, or both within Earth that produce solid-state mineralogical, chemical, and textural changes that alter the features of preexisting rocks
