Geology

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1. 3 Heat, pressure & chemically active fluids 21. assimilation in igneous activity, the process of
metamorphism incorporating country rock into a magma
agents body
2. 4 main kinds of cirque, valley, piedmont, and ice sheet 22. asthenosphere a subdivision of the mantle situated below
glaciers the lithosphere. This zone of weak material
exists below a depth of about 100
3. 5 to almost 700 Range of depths of earthquakes
kilometers and in some regions extends as
km
deep as 700 kilometers. The rock within
4. 50 to 200 years Great earthquakes should occur about this zone is easily deformed.
5. 90% Percent of all earthquakes occur at depths 23. asymmetric produced by a current that flowed from the
of less than 100 km ripple marks gentle side toward the steep side
6. 95% percent of energy released by earthquakes; 24. atmosphere the gaseous portion of a planet; the planet's
originates in a few relatively narrow zones envelope of air. One of the traditional
that wind around the globe subdivisions of Earth's physical
7. aa moves slow and has a high viscosity environment.
25. atom the smallest particle that exists as an
8. Ablation wastage; loss of snow and ice by melting
element
and by sublimation (direct change from ice
to water vapor, without melting) 26. atomic number the number of protons in the nucleus of an
atom
9. abrasion the wearing away of rock by a grinding
action 27. basalt extrusive, most common igneous rock,
aphanitic; found in Hawaii and Iceland,
10. abyssal plains very level area of the deep-ocean floor,
central Oregon and Washington
usually lying at the foot of the continental
rise. 28. basaltic a compositional group of igneous rocks,
composition indicating that the rock contains
11. Accumulation occurs usually in snowfields regions of
substantial dark silicate minerals and
permanent snow cover
calcium rich plagioclase feldspar
12. active volcano is one that is errupting or has
29. batholith mass of rock formed when a large body of
shown signs that it may erupt in the near
magma cool inside tthe crust
future
30. batholiths A very large intrusive igneous rock mass
13. Aftershocks smaller quakes produced after a major
that has been exposed by erosion and with
quake caused by rocks shifting to new
an exposed surface area of over 100 square
positions
kilometers.
14. a-horizon made of topsoil, composed of humus
31. beds layers of sediment
15. andesite medium-gray, fine-grained volcanic rock;
32. b-horizon the subsoil; made of clays and sands
extrusive, intermediate composition,
commonly porphyritic 33. biogenic rock composed primarily of the remains of
16. andesitic intermediate, between granite and basalt in sedimentary living organisms
color, named from andesite rock

17. angular grains that have not moved far from their 34. biosphere includes all life on Earth.
source; tend to have sharp edges and 35. Body waves Travel through Earth's interior; two types
corners
36. Bowen's illustrates the relationship between magma
18. aphanitic a texture of igneous rocks in which the reaction series and the minerals crystallizing from it
crystals are too small for individual during the formation of igneous rock
minerals to be distinguished without the
aid of a microscope--fine-grained texture 37. breccia conglomerate/breccia; which is angular?

19. arete A narrow, knife-like ridge separating two 38. Burial Associated with very thick sedimentary
adjacent glaciated valleys. metamorphism strata; Required depth varies from one
location to another depending on the
20. arkose sandstone/arkose; which is
prevailing geothermal gradient
mineralogically immature?
39. caldera huge hole left by the collapse of a volcanic 60. columnar joints a pattern of cracks that forms during
mountain cooling of molten rock to generate
columns
40. carbonate consists mostly of calcite or dolomite
rocks 61. compaction when the weight of overlying
sediment squeezes out air/water
41. catastrophism the concept that earth was shaped by
thereby fitting the clasts more
catastrophic events of a short-term nature.
tightly together - process
42. cement ions precipitated from groundwater in the
62. composite volcanoes are tall, cone-shaped mountains in
spaces between clasts that hold the clasts
which layers of lava alternate with
together
layers of ash.
43. cementation ion-rich groundwater passes through the
63. composition what are rock is made of impacts its
compacted sediment, minerals precipitate
rate of weathering
and bind or "glue" the clasts together
64. compound is a substance made of two or more
44. Changes in from regions of low-grade metamorphism to
elements that have been chemically
mineralogy regions of high-grade metamorphism
combined.
occur...
65. concordant plutons that form parallel to
45. chemical a substance formed by the chemical
surrounding rock
compound combination of two or more elements in
definite proportions and usually having 66. conglomerate conglomerate/breccia; which is
properties different from those of its rounded?
constituent elements
67. conglomerate/breccia consists of pebbles/cobbles
46. Chemically Mainly water with other volatile
68. contact occurs when magma heats the
Active Fluid components; enhances migration of ions;
metamorphism surrounding rock and changes its
aids in recrystallization of existing minerals
mineral composition, mineral heats
47. chemical the breaking and forming of chemicals surrounding rock as it moves toward
reactions bonds the surface, causing some to change
48. chemical the breakdown a rock with a change to its 69. contact or thermal driven by a rise in temperature
weathering composition metamorphism within the host rock; heat from
49. chemical the processes by which the internal structure magma
weathering of a mineral is altered by the removal and/or 70. continental margin that portion of the seafloor adjacent
addition of elements to major landmasses.
50. chemical process during which rokc chemically reacts 71. continental rise the gently sloping surface at the
weathering with air, water, and acidic solutions base of the continental slope.
51. chert composed of cryptocrystalline silica 72. continental shelf the gently sloping submerged
portion of the continental margin,
52. cinder cone material build up around the vent in a steep,
extending from the shoreline to the
sone-shaped hill or small mountain
continental slope.
53. cirque steep sided, half bowl shaped recess at the
73. continental slope the steep gradient that leads to the
head of the glacier
deep-ocean floor and marks the
54. Cirque glacier small, semicircular to triangular glaciers seaward edge of the continental
that from on sides of mountains shelf.
55. clastic texture in which discrete grains are held together by 74. convergent plate a boundary in which two plates
cement (texture) boundaries move together, resulting in oceanic
56. cleavage the tendency of a mineral to break along lithosphere being thrust beneath an
planes of weak bonding overriding plate, eventually to be
reabsorbed into the mantle; can also
57. closed systems systems that are self-contained with regard
involve the collision of two
to matter.
continental plates to create a
58. coal composed primarily of carbon derived from mountain system.
plants
75. coquina limestone composed of a mass of
59. color a phenomenon of light by which otherwise shells that have undergone mineral
identical objects may be differentiated diagenesis
76. core located beneath the mantle, it is Earth's 95. diagnesis any chemical or physical change that happens
innermost layer. The core is divided into in a sedimentary environment subsequent to
an outer core and inner core. the original deposition of sediment
77. covalent bond a chemical bond produced by the sharing 96. dike tabular-cuts through surrounding rock
of electrons
97. dike magma forces itself across rock layers and
78. crater is a bowl-shaped area that may form at hardens
the top of a volcano around the central
98. diorite intrusive equivalent of andesite--phaneritic
vent
99. discordant plutons that cut across existing rock structures
79. Crevasses open fissures that form when the velocity
of ice flow is variable; two types - 100. dissolution when acidic solutions react with rock
transverse and longitudinal
101. dissolution the process of going into solution
80. cross beds inclined surfaces; subtle curving surfaces,
delineated by coarser and/or denser 102. dissolved charged atoms or molecules in a water solution
grains, lie at an angle to the main ions
bedding surfaces 103. divergent boundary where two plates move apart
81. crust the thin outermost layer of Earth. plate resulting in the upwelling of material from the
boundaries mantle to create new seafloor.
82. cryptocrystalline rocks where the grains are so small that
104. dolostone rock containing significant amounts of
rocks the rock looks somewhat like porcelain
dolomite
83. crystalline one in which crystals are interlocking
105. dormat volcano to awaken in the future and become
texture (texture)
active
84. crystallization the formation and growth of a crystalline
106. drift accumulation of deposits or rocky gravel, sand
solid from a liquid or gas
silt, and clay from melting;
85. crystal settling during the crystallization of magma, the
107. drumlin a mound of glacial drift
earlier formed minerals are denser than
the liquid portion and settle to the bottom 108. During ended about 10,000 years ago, think ice cover
of the magma chamber Pleistocene most of Canada, large parts of Alaska, and the
86. dark silicates silicate minerals containing ions of iron epoch or northern contiguous US
and/or magnesium in their structure; also ice age
called ferromagnesian silicates 109. Earthquake The vibration of Earth produced by the rapid
87. decompression melting that occurs as rock ascends due to release of energy
melting a drop in confining pressure 110. Earth Systematic approach to physical geography
88. Deep Focus over 300 km; almost all occur in circum- system that looks at the interaction between the
pacific belt science earth's physical systems and processes on a
global scale.
89. deep-ocean the portion of seafloor that lies between
basin the continental margin and the oceanic 111. Elastic Slippage at the weakest point (the focus)
ridge system. This region compromises rebound occurs; vibrations occur as the deformed rock
almost 30% of Earth's surface. "springs back" to its original shape

90. deep-ocean extremely deep depressions on the ocean 112. electron a negatively charged subatomic particle that
trenches floor that are occasionally more than has a negligible mass and is found outside the
11,000 meters deep. atom's nucleus

91. density the weight per unit volume of a particular 113. element a substance that cannot be decomposed into
material simpler substances by ordinary chemical or
physical means
92. deposition when moving water or wind slows, or
when the ice melts, clasts settle out and 114. element is a substance that cannot be broken down into
accumulate other substances.

93. depositional like land surface, the sea floor, or a river 115. Epicenter location on the surface directly above the focus;
environments bed located using the difference in velocities of P &
S waves
94. Depositional kames, lateral moraines, medial moraine,
features terminal moraine crevasses, out wash
plains, kettles, drumlins, eskers.
116. Erosional 1) glacial trough 2) truncated spur 3) 134. Foreshocks small earthquakes that come before a major
features paternoster lakes 4) arete 5) horn 6) fjord 7) earthquakes
cirque 8) roche mountanee
135. fossils The remains or traces of organisms preserved
117. esker long ridge of material deposited by a meltwater from the geologic past.
stream flowing beneath a glacier
136. fracture relates to the breakage of minerals when there
118. evaporite consists of salts that precipitate when saltwater are no planes of weakness in the crystalline
rocks evaporates structure; (examples: conchoidal, irregular, &
splintery)
119. Examples Parallel alignment of platy and/or elongated
of minerals; Parallel alignment of flattened 137. frost the mechanical breakup of rock caused by the
foliation mineral grains and pebbles; Compositional wedging expansion of freezing water in cracks and
banding; Slaty cleavage - where rocks can be crevices
easily split into thin, tabular sheets
138. gabbro intrusive equivalent of basalt; common in
120. exfoliation a mechanical weathering process which oceanic crust
removes protuding overlying layers and
139. geology the science that examines the Earth, its form
esposing the weathered down dome of the
and composition, and the changes it has
underlying layers
undergone and is undergoing.
121. extinct volcano is unlikely to erupt again.
140. geosphere the solid Earth; one of Earth's four basic
122. extrusive igneous rocks that occur at Earth's surface spheres.
igneous 141. geothermal magma a few kilometers beneath earths
rocks activity surface heat underground water
123. Fault Slow gradual displacement of some portions of 142. Geothermal An increase in temperature with depth due to
creep fault gradient the
124. Faults Large fractures in the Earth's crust that are 143. geothermal the gradual increase in temperature with depth
associated with movements that produce gradient in the crust, the avg is 30C per km in the upper
earthquakes crust
125. felsic Describes magma or igneous rock that is rich in 144. geyser fountain of water and steam that erupts from
feldspars and silica and that is generally light in the ground
color.
145. glacial when glaciers melt, it appears to retreat up the
126. finger lake a body of water that forms in a long, narrow, U- retreat valley from which it flowed
shaped glacial valley, often partly dammed with
ice at the end by a mound of glacial moraine 146. glacial a deep, U-shaped valley carved by an alpine
sediment trough glacier.

127. fjord a long narrow inlet of the sea between steep 147. Glacier from snowflake to mountain ice - water, snow,
cliffs grows fern, compaction, thaw/freeze, expand,
absorb, rain, weight, glacial ice
128. Focus Point at the depth where the rocks ruptured to
produce earthquakes; place where quake waves 148. Glaciers large masses that form on land areas that are
originate cold enough and have enough snowfall to
sustain them
129. Focus The source of the energy that radiates in all
directions from here in the form of waves 149. glaciers annual build up of accumulation, gravity
move
130. Foliated any planar arrangement of mineral grains or
structural features within a rock 150. glass natural glass produced when molten lava cools
too rapidly to permit crystallization; a solid
131. Foliated Slate, Phyllite, Schist, and Gneiss composed of unordered atoms
rocks
151. glassy Term for the texture of rocks with no crystals,
132. Foliated slaty or rock cleavage, gneissic, Schistosity but may have vesicles.
textures
152. gneiss Medium to coarse grained; Banded appearance
133. Foliation Rotation of platy and/or elongated minerals; High-grade metamorphism; Often composed of
formed in Recrystallization of minerals in the direction of white or light-colored feldspar-rich layers with
several preferred orientation; Changing the shape of bands of dark ferromagnesian minerals
ways equidimensional grains into elongated shapes
that are aligned
153. Gneissic During higher grades of metamorphism, 173. igneous A rock formed by the crystallization of
ion migration results in the segregation of molten magma
minerals
174. igneous rocks a rock formed by the crystallization of
Gneissic rocks exhibit a distinctive banded
molten magma.
appearance
175. Impact Occurs when high speed projectiles called
154. granite best known of all igneous rocks, intrusive--
metamorphism meteorites strike Earth's surface; Products
found in Barre, Vermont; Mount Airy, North
are called impactites
Carolina
176. Importance of Most metamorphic rocks have the same
155. granitic a compositional group of igneous rocks that
parent rock overall chemical composition as the
composition indicate a rock is composed almost entirely
parent rock from which they formed;
of light-colored silicates, mainly quartz and
Mineral makeup determines, to a large
feldspar
extent, the degree to which each
156. groundmass small crystals in a porphyritic igneous rock metamorphic agent will cause change

157. ground a blanket of till deposited by a glacier or 177. Index minerals good indicators of the metamorphic
moraine released as glacier ice melted conditions in which they form

158. habit refers to the common or characteristic 178. inner core the solid, inner most layer of the Earth,
shape of a crystal or aggregate of crystals about 1216km in radius.

159. hardness a mineral's resistance to scratching and 179. Intensity a measure of the degree of quake shaking
abrasion at a given locale based on amount of
damage
160. Heat Most important agent; two sources - contact
metamorphism & geothermal gradient 180. Intermediate between 70to 300 km

161. H.F. Reid First explained mechanism for earthquakes 181. intermediate a composistional group of igneous rocks
composition indicating that the rock contains al least
162. historical a major division of geology that deals with
25% dark silicate minerals, the other
geology the origin of Earth and its development
dominate mineral is plagioclase feldspar
through time. Usually involves the study of
fossils and their sequence in rock beds. 182. intrusions also known as plutons; a structure that
results from the emplacement and
163. horn A pyramid-like peak formed by glacial
crystallization of magma beneath the
action in three or more cirques surrounding
surface of the Earth
a mountain summit.
183. intrusive igneous rocks formed below the surface of
164. hot and this is the climate that most promotes
igneous rocks the Earth
humid chemical weathering
184. ion an atom or molecule that possesses an
165. hot spot is an area where material from deep within
electrical charge
the mantle rises and then melts, forming
magma. 185. ionic bond a chemical bond between two oppositely
charged ions formed by the transfer of
166. humus made of dead plant and animal material
valence electrons from one atom to
167. hydrolysis the chemical reaction of rocks to water another

168. hydrosphere the water portion of Earth; one of the 186. island arc is made volcanoes that created a string of
traditional subdivisions of Earth's physical island
environment. 187. isotope varieties of the same element that have
169. Hydrothermal chemical alterations from hot, ion-rich different mass numbers; their nuclei
water contain the same number of protons but
different numbers of neutrons
170. hypothesis a tentative explanation that is tested to
determine if it is valid. 188. kames an irregularly shaped hill or mound
composed of sand, gravel and till that
171. Ice sheet vast, pancake shaped ice mound that covers
accumulates in a depression on a
a large section of a continent and flows
retreating glacier, and is then deposited on
independent of the topo features beneath it
the land surface with further melting of the
172. ice sheet Antarctic and Greenland glacier.
examples
189. kettle a small depression that forms when a
chunk of ice is left in glacial till
190. Knowing 1) conducting work such as regional soil 211. magma a body of molten rock found at depth,
landforms analyses, 2) studies of surface drainage and including any dissolved gases and crystals
water supply, 3) exploration for sources of
212. magma pocket where magma collects
sand, gravel, and minerals
chamber
191. laccoliths igneous intrusion that has been injected
213. magma mixing the process of altering the composition of a
between two layers of sedimentary rock.
magma through the mixing of material
192. land break rocks, bulldozes, frost active, frozen, from another magma body
sculptured carried away, scratches grooves
214. magmatic the formation of one or more secondary
by glaciers
differentiation magmas from a single parent magma
193. Large hollow Chinese used this to measure seismic activity
215. Magnitude estimates the amount of energy released at
jar with suspended free motion mass
the source of the quake
194. lateral rock material that accumulated along the side
216. Major Circum-Pacific belt, Mediterranean Sea
moraine of a glacier
earthquake region to Himalayan complex & oceanic
195. lava this is what magma turns into when it has zones ridge system (underwater mountains)
reached the surface.
217. mantle the 2885km thick layer of Earth located
196. lava magma that reaches the Earth's surface below the crust.

197. lava flow is a area covered in lava 218. Marble Coarse, crystalline; Parent rock was
limestone or dolostone; Composed
198. leaching when water soaks through soils layers and
essentially of calcite or dolomite crystals;
strips it of nutrients
Used as a decorative and monument stone;
199. light silicate minerals that lack iron and/or Exhibits a variety of colors
silicates magnesium; also called nonferromagnesian
219. massive huge in size--3 types: batholith-100 km
silicates
squared; stocks-<100 km squared;
200. limestone general class of rocks form from shells of xenolith-stranger
calcite-secreting organisms
220. mass number the sum of the number of neutrons and
201. lithification over time, accumulation of clasts are buried. protons in the nucleus of an atom
when this happens the weight of overlying
221. Mechanism Rocks on either side of fault are deformed
sediment squeezes out air/water thereby
for by tectonic forces, bend and store elastic
fitting the clasts more tightly together
earthquakes energy, frictional force is overcome
202. lithosphere the rigid outer layer of earth, including the
222. medial A moraine formed when two advancing
crust and upper mantle.
moraine valley glaciers come together to form a
203. lithospheric a coherent unit of Earth's rigid outer layer single ice stream, forms in the middle of the
plate that includes the crust and upper mantle. glacier
204. Locating the a circle with radius equal to distance to 223. melt the liquid portion of magma excluding the
epicenter epicenter drawn around each station; point solid crystals
where all 3 circles intersect is epicenter
224. metallic bond a chemical bond present in all metals that
205. Longitudinal aligned with the direction of flow may be characterized as an extreme type of
crevasses electron sharing in which the electrons
move freely from atom to atom
206. lower mantle the part of the mantle that extends from a
depth of 660km to the top core, at a depth of 225. Metamorphic contact or thermal, hydrothermal, regional,
2900km. environments burial, along fault zones & Impact
207. luster the appearance or quality of light reflected 226. metamorphic rocks formed by the alteration of
from the surface of a mineral rock preexisting rock deep within Earth (but still
in a solid state) by heat, pressure, and/or
208. mafic describes magma or igneous rock that is rich
chemically active fluids.
in magnesium and iron and that is generally
dark in color 227. Metamorphic Northeastern US
zones in US
209. Magma is a molten mixture of rock-forming
substances, gases, and water from the mantle
210. magma a body of molten rock found at depth,
including any dissolved gases and crystals.
228. Metamorphism The transition of one rock into another by 244. obsidian dark colored glassy rock: composed of light
temperatures and/or pressures unlike colored igneous rocks and small amounts of
those in which it formed metallic ions
229. Metamorphism Metamorphism along fault zones; Occurs 245. oceanic a continuous elevated zone on the floor of all
along fault at depth and high temperatures; Pre- (mid-ocean) the major ocean basins and varying in width
zones existing minerals deform by ductile flow ridge from 500-5000 kilometers; the rifts at the
crets of these ridges represent divergent plate
230. Metamorphism incrementally from low-grade to high-
boundaries.
progresses grade
246. open systems both energy and matter flow in and out of the
231. Metasomatism Change in composition by interaction with
system.
fluids
247. ore usually a useful metallic mineral that can be
232. micrite limestone composed of very tiny calcite
mined at a profit; the term is also applied to
particles - solidified lime mud
certain nonmetallic minerals such as fluorite
233. Migamtites Highest grades of metamorphism that is and sulfur
transitional to igneous rocks; Contain
248. organic rocks contain remnants of organic chemicals and
light bands of igneous components along
may be more than 90% carbon
with areas of unmelted metamorphic rock
249. outer core a layer beneath the mantle about 2270 km
234. mineral a naturally occurring, inorganic,
thick that has the properties of a liquid.
crystalline material, with a unique
chemical structure 250. out-wash sediment deposited in front of a glacier by
plain streams of melt-water
235. Modified developed using CA buildings; drawback
Mercalli not true measure of quakes actual severity; 251. oxidation the chemical reaction of rocks to oxygen
Intensity Scale Guiseppe Mercalli; 1-12 in Roman
252. oxidation a chemical change in which a substance
numerals; I - least; XII - most; used after
combines with oxygen, as when iron
quake
oxidizes, forming rust
236. Mohs scale a series of 10 minerals used as a standard
253. pahoehoe is fast-moving, hot lava that has low vicosity
in determining hardness
254. parent immature soils are started by the weathering
237. Mountain characterized by cirque glaciation, valley
bedrock of this
glaciation glaciers, and piedmont glaciers; also
called alpine glaciation, because it is the 255. Parent rocks Igneous rocks, Sedimentary rocks, Other
type seen in Europe's Alps of metamorphic rocks
metamorphic
238. nebular theory a model for the origin of the solar system
rocks
that supposes a rotating nebula of dust
and gases that contracted to form the Sun 256. partial the process by which most igneous rocks
and planets. melting melt
239. negative as used in climatic change, any effect that 257. paternoster A chain of lakes in a glacial valley.
feedback is opposite of the initial change and tends lake
mechanism to offset it.
258. pegmatic texture formed in coarse-grained igneous
240. neutron a subatomic particle found in the nucleus rocks that are composed of interlocking
of an atom; it is electrically neutral, with a crystals of larger than one centimeter in
mass approximately equal to that of a diameter
proton
259. pegmatite a very coarse-grained igneous rock (typically
241. Non-foliated Lack of apparent foliation; Develop in granite) commonly found as a dike
environments where deformation is associated with a large mass of plutonic rock
minimal; that has smaller crystals; crystallization in a
Typically composed of minerals that water-rich environment is believed to be
exhibit equidimensional crystals responsible for the very large crystals
242. Non-foliated Marble & Quartzite 260. periodic the tabular arrangement of the elements
rocks table according to atomic number
243. nucleus the small, heavy core of an atom that 261. phaneritic igneous rock texture where crystals are equal
contains all of its positive charge and most in size and identifiable to the naked eye--
of its mass coarse-grained texture
262. phenocysts large crystals in a porphyritic igneous 278. Primary (P) travel 1.7 times faster than S waves;
rock waves travel through whole interior; motion is
back & forth
263. Phyllite Gradation in the degree of metamorphism
between slate and schist; Platy minerals 279. proton a positively charged subatomic particle
not large enough to be identified with the found in the nucleus of an atom
unaided eye; Glossy sheen and wavy
280. pumice volcanic rock with a glassy texture of a
surfaces
gray, frothy mass
Exhibits rock cleavage; Composed mainly
of fine crystals of muscovite and/or 281. pyroclastic an igneous rock texture resulting from
chlorite the consolidation of individual rock
fragments that are ejected during a
264. physical geology a major division of geology that examines
violent volcanic eruption--fragmental
the materials of Earth and seeks to
texture
understand the processes and forces
acting upon Earth's surface from below. 282. pyroclastic flow occurs when an explosive eruption hurls
out a mixture of hot gases, ash, cinders,
265. physical like hitting a rock with a hammer, which
and bombs.
weathering breaks the rock into fragments (clasts),
but does not change the minerals making 283. Quartzite Formed from a parent rock of quartz-rich
up the rock sandstone; Quartz grains are fused
together
266. physical weathering that changes the shape and
weathering size of rocks without changing the 284. radioactive the spontaneous decay of certain
chemical makeup of the rock decay unstable atomic nuclei

267. Piedmont mergers of two or more valley at the foot 285. recessional Both Continental and Mountain
glaciers of a mountain range moraine Glaciation- Ridge of till that forms at
terminus of a glacier, behind (up-glacier)
268. pipe a long tube that connects the magma
and generally parallel to the terminal
chamber to earths surface
moraine; formed during a temporary halt
269. plates a coherent unit of Earth's rigid outer layer (stand in recession of a wasting glacier.
that includes the crust and upper mantle.
286. Recrystallization in new, stable minerals
270. plate tectonics the theory that proposes that earth's outer results
shell consists of individual plates that
287. Regional Occurs during mountain building;
interact in various ways and thereby
metamorphism produces the greatest volume of
produce earthquakes, volcanoes,
metamorphic rock; rocks usually display
mountains, and the crust itself.
zones of contact and/or hydrothermal
271. Plate Tectonics Most of the motion along faults can be metamorphism
Theory explained by this
288. relative dating rocks are placed in their proper sequence
272. plutonic rocks igneous rocks that form at depth or order; only the chronological order of
events is determined.
273. porphyritic an igneous rock texture characterized by
two distinctly different crystal sizes 289. residual soil that is in the same location that it
was created
274. Porphyroblastic Large grains, called porphyroblasts, are
textures surrounded by a fine-grained matrix of 290. rhyolite extrusive equivalent of granite--
other minerals; Porphyroblasts are composed of light colored silicates--
typically garnet, staurolite, and/or Yellowstone Park
andalusite 291. ring of fire a major volcanic belt that formed by
275. porphyry an igneous rock with a porphyritic texture many volcanoes that rim the Pacific
Ocean.
276. positive as used in climatic change, any effect that
feedback acts to reinforce the initial change. 292. roche (Rock mutton) French - a rock outcrop
mechanism mountanee that has been molded by glacial ice into a
specific shape by the movement of ice
277. Pressure Increases with depth; confining pressure
from one direction
(stress) applies forces equally in all directions;
rocks may also be subjected to differential 293. rock a consolidated mixture of minerals
stress, which is unequal in different
directions
294. rock cycle a model that illustrates the origin of the 308. sedimentary rock that forms at or near the earth's
three basic rock types and the rock surface by one of the following processes:
interrelatedness of Earth materials and compacting/cementation; accumulation
processes. of layers; cementing together of shells;
accumulation/alteration of organic
295. rock gypsum composed of gypsum
material
296. rock salt composed of halite
309. sedimentary beds; either fairly homogeneous or
297. root wedging In this type of physical weathering, the structures internal variations; provide important
roots of a plant (typically a tree) wedge information about a rock's history
into a crack in a rock and, as the plant
310. sediments unconsolidated particles created by the
growns, splits the rock.
weathering and erosion of rock, by
298. rounded rocks that eventually become almost chemical precipitation from solution in
spherical water, or from the secretions of
organisms and transported by water,
299. San Andreas Most studied fault system
wind, or glaciers.
300. sandstone/arkose consists of sand
311. Seismograms Records obtained from seismographs
301. Schist Medium to coarse grained; Platy
312. Seismograph Instruments that record seismic waves
minerals predominate; Commonly
include the micas 313. Seismologists People who study earthquakes and their
The term schist describes the texture; characteristics
To indicate composition, mineral
314. Seismology The study of earthquake waves; dates
names are used (such as mica schist)
back to the Chinese almost 2000 years
302. Schistosity Platy minerals are discernible with the ago
unaided eye and exhibit a planar or
315. shale shale/mudstone; which one breaks into
layered structure; Rocks having this
thin plates?
texture are referred to as schist
316. shale/mudstone consists of clay
303. seafloor hypothesis first proposed in the 1960s
spreading by Harry Hess, suggesting that new 317. Shallow surface to 70 km; occur along oceanic
oceanic crust is produced at the crest of ridge system; nearly all damaging quakes
mid-oceanic ridges, which are the sites originate at this depth; not much room so
of divergence. more damage

304. seamounts an isolated volcanic peak that rises at 318. sheild volcano lave flows graudally builds a wide, gently
least 1000 meters above the deep-ocean sloping mountain
floor. 319. shields a large, relatively flat expanse of ancient a
305. Secondary (S) shaking motion at right angles; travels metamorphic rock with the stable
waves only through solids; slower velocity continents interior.
than P waves; slightly greater 320. silica is made up of particles of the elements
amplitude than P waves oxygen and silicon.
306. sediment consists of loose grains derived from 321. silicates any one of numerous minerals that have
fragmented rock, of shells and shell the silicon-oxygen tetrahedron as their
fragments, of plant debris, or of mineral basic structure
crystals precipitated from water bodies
at the earth's surface 322. siliceous rocks consist primarily of quartz

307. sedimentary rock rock formed from the weathered 323. silicon-oxygen a structure composed of four oxygen
products of preexisting rocks that have tetrahedron atoms surrounding a silicon atom that
been transported, deposited, and constitutes the basic building block of
lithified. silicate minerals
324. sill tabular-parallel to surrounding rock

325. sill magma squeezes between horizontal

layers of rock
326. siltstone consists of silt
327. size and what 4 main kinds of glaciers are based on 350. Terminus bottom end of glacier
form
351. Texture refers to the size, shape, and
328. Slaty Slaty cleavage - where rocks can be easily arrangement of grains within a rock
cleavage split into thin, tabular sheets
352. texture the size, shape, and distribution of the
329. Slaty or rock Closely spaced planar surfaces along which particles that collectively constitute a
cleavage rocks split; Can develop in a number of ways rock
depending on metamorphic conditions and
353. theory a well tested and widely accepted view
parent rock
that explains certain observable facts.
330. Snowline boundary between zones; elevation above
354. Three At least this many station recordings
permanent snow cover
needed to locate an epicenter
331. soil a mixture of weathered rocks and organic
355. till drift that accumulated directly from
materials
the melting ice and is unstratified
332. soil profile displays the layers of a mature soil
356. transformation a boundary in which two plates slide
333. soil profile ... fault boundaries past each other without creating or
destroying lithosphere.
334. solid During metamorphism the rock must remain
essentially... 357. transported soil that has been moved by an agent
of erosion
335. sorting (of a clastic sedimentary rock) measure of the
uniformity of grain size and can also help to 358. Transverse perpendicular to the flow direction
identify the transporting agent crevasses

336. Sources of Pore spaces of sedimentary rocks, Fractures 359. Travel-time graph used to determine each station's
fluids in igneous rocks, and Hydrated minerals such distance to the epicenter
as clays and micas 360. travertine composed of carbonate
337. specific the ratio of a substance's weight to the weight
361. truncated spur Triangular-shaped cliff produced
gravity of an equal volume of water
when a spur of land that extends into
338. stocks Irregularly shaped plutons that are similar to a valley is removed by the great
batholiths but smaller in size erosional force of a valley glacier.
339. stratified drift transported by melt water becomes sorted 362. tuff most common pyroclastic rock;
by size, layered is this composed of tiny, ash-size fragments
that were later cemented together
340. streak the color of mineral in powdered form
363. Two kinds of body Primary (P) and Secondary (S)
341. subduction a long, narrow zone where one lithospheric
waves
zone plate descends beneath another.
364. Two Intensity and Magnitude
342. subrounded smoothe edges and corners
measurements of
343. surface area when this factor is increased, rocks weather earthquake size
faster
365. Two zones of accumulation and ablation
344. Surface Travel along the Earth's surface; cause glaciers
waves greatest destruction; slow & great
366. Types of Shallow, Intermediate & Deep Focus
345. symmetric have steep slopes on both sides and form from earthquakes
ripple oscillating currents
367. Types of Foliated and non-foliated. Deals with
marks
metamorphic rock the way a rock is divided.
346. Systematic in the mineralogy and often the textures of
368. Types of seismic Surface, Body
variations.... metamorphic rocks are related to the
waves
variations in the degree of metamorphism
369. uniformitarianism the concept that the processes that
347. tabular table top--3 types: dike-discordant intrusive;
have shaped earth in the geologic past
sill-concordant intrusive; laccolith
are essentially the same as those
348. tenacity describes a mineral's toughness or its operating today.
resistance to breaking or deforming
349. terminal Till deposited at the leading edge of a melting
moraine glacier
370. valence the electrons involved in the bonding 388. xenoliths fragments of country rock in intrusive body
electron process; the electrons occupying the highest
389. Zone of glacial ice formed in zone of accumulation
principal energy level of an atom
ablation and flows downhill this zone, where it melts
371. Valley glacier long glaciers that flow down stream valleys or sublimes faster than new ice can form
in the mountains
390. Zone of as snow and ice collect in this zone, they
372. vent opening where gases and molten rock leave accumulation become compacted and highly recrystallized
under their weight; large snowfield
373. vesicular a term applied to aphanitic igneous rocks
that contain many small cavities called
vesicles
374. viscosity is the resistance of a liquid to flowing.

375. volatiles gaseous components of magma dissolved in

the melt. They will readily vaporize at
surface pressures
376. volcanic pyroclastic rocks composed mainly of
breccia particles larger than ash
377. volcanic neck forms when magma hardens in a volcanos
pipe
378. volcanic igneous rocks that form at the surface
rocks
379. volcano is a weak spot in the crust where molten
material, or magma, comes to the surface.
380. Water bodies Inlets, gulfs, lakes and rivers

381. Waves Wavelength, crest, trough and amplitude

382. weathering the breakdown of rock due to exposure to the

atmosphere
383. weathering the chemical/physical breakdown of
preexisting rock
384. welded tuff tuff formed when the ash particles remained
hot enough to fuse; consists mainly tiny
glass shards
385. wetting and breaks up rocks that contain clay clay swells
drying when wet and shrinks when dry constant
swelling and shrinking causes rocks like
shale to fall apart
386. Why glaciers Glaciers form in higher elevations and polar
form? regions where the rate of snowfall exceeds
the melting rate of the snow. As the snow
accumulates, the pressure caused by the
weight of the overlying snow causes it to
recrystallize into ice. Eventually the ice can
become so heavy that it starts to move
downward under its own weight.
387. Wisconsinian most recent; left behind many erosional &
glaciation depositional features; reached maximum
about 18,000 years ago, when a Laurnetide
ice sheet ice sheet covered central and
eastern Canada, Great Lakes Region and the
north eastern US which ended about 10,000
years ago.