Download chapter 9 vocabulary terms

Earth Science 11th Edition Vocabulary Chapter 9
By Reshawn Brown (GLY 1001 Student North Campus Fall 2006)
1.
AA flow (p. 254) – A type of lava flow that has a jagged blocky surface.
2.
Batholith (p. 270) – A large mass of igneous rock that formed when magma
was emplaced at depth, crystallized, and subsequently exposed by erosion.
3.
Caldera (p. 263) – A large depression typically caused by collapse or
ejection of the summit area of a volcano.
4.
Cinder Cone (p. 259) – A rather small volcano built primarily of pyroclastics
ejected from a single vent.
5.
Columnar Joint (p. 269) – A pattern of cracks that form during cooling of
molten rock to generate columns that are generally six-sided.
6.
Composite Cone (p. 260) – A volcano composed of both lava flows and
pyroclastic materials.
7.
Conduit (p.256) – A pipelike opening through which magma moves toward
Earth’s surface. It terminates at a surface opening called a vent.
8.
Continental Volcanic Arc (p. 278) – Mountains formed in part by igneous
activity associated with the seduction of oceanic lithosphere beneath a continent.
9.
Crater (p. 256) – The depression at the summit of a volcano, or that which is
produced by a meteorite impact.
10.
Decompression Melting (p. 271) – Melting that occurs as rock ascends due
to a drop in confining pressure.
11.
Dike (p. 269) - A tabular –shaped intrusive igneous feature that is cuts
through the surrounding rock.
12.
Fissure (p. 255, 265) – Volcano activity frequently begins when a (crack)
develop in the crust as magma moves forcefully toward the surface.
13.
Fissure eruption (p. 266) – An eruption in which lava is extruded from
narrow fractures or cracks in the crust.
14.
Flood basalt (p. 266) – Flows of basaltic lava that issue from numerous
cracks or fissures and commonly cover extensive areas to thickness of thousands
of meters.
15.
Furmarole (p.256) – A vent in a volcanic area from which fumes or gases
escape.
16.
Geothermal Gradient (p. 271) – The gradual increase in temperature with
depth in the crust. The average is 30*C per kilometer in the upper crust.
17.
Hot Spot (p. 279) – A concentration of heat in the mantle capable of
producing magma, which in turn extrudes onto Earth’s surface. The intraplate
volcanism that produced the Hawaiian Islands is one example.
18.
Intraplate Volcanism (p. 279) – Igneous activity that occurs within a tectonic
plate away from boundaries.
19.
Island Arc (p.278) – See Volcanic island arc
20.
Laccolith (p.269) – A massive igneous body intruded between preexisting
strata.
21.
Lahar (p.262) – Mudflows on the slopes of volcanoes that result when
unstable layers of ash and debris become saturated.
22.
Mantle Plume (p. 279) – A mass of hotter than normal mantle material that
ascends toward the surface, where it may lead to igneous activity. These plumes
of solid yet mobile material may originate as deep as the core-mantle boundary.
23.
Muee Ardente (p. 262) – Destructive fiery flows, capable of racing down
steep volcanic slopes at speeds that can approach 200 kilometers (125) per hour.
24.
Pahoehoe Flow (p. 254) – A lava flow with a smooth-to-ropey surface.
25.
Parasitic Cone (p. 256) – A volcanic cone that forms on the flank of a larger
volcano.
26.
Partial Melting (p. 273) – The process by which most igneous rocks melt.
Since individual minerals have different melting points, most igneous rocks melt
over a temperature range of a few hundred degrees. If the liquid is squeezed out
after some melting has occurred, a melt with a higher silica content results.
27.
Pipe (p. 256) – A vertical conduit through which magmatic materials have
passed.
28.
Pluton (p. 267) – A structure that results from the emplacement and
crystallization of magma beneath the surface of Earth.
29.
Pyroclastic Flow (p. 255) – A highly heated mixture, largely of ash and
pumice fragments, traveling down the flanks of a volcano or along the surface of
the ground.
30.
Pyroclastic Material (p. 262) – The volcanic rock ejected during an eruption,
including ash, bombs, and blocks.
31.
Scoria Cone (p. 259) – See cinder cone
32.
Shield Volcano (p. 257) – A broad, gently sloping volcano built from fluid
basaltic lavas.
33.
Sill (p. 269) – A tabular igneous body that was intruded parallel to the
layering of preexisting rock.
34.
Strato volcanoes (p. 260) – See composite cone.
35.
Vent (p. 256) – surface opening
36.
Viscosity (p. 253) – A measure of a fluid’s resistance to flow.
37.
Volatiles (p. 253) – Gaseous components of magma dissolved in the melt.
Volatiles will readily vaporize (form a gas) at surface pressures.
38.
Volcanic Island Arc (p. 278) – A chain of volcanic islands generally located a
few hundred kilometers from a trench where active subduction of one oceanic
slab beneath another is occurring.
39.
Volcanic Neck (p. 267) – An isolated, steep-sided, erosional remnant
consisting of lava that once occupied the vent of a volcano.
40.
Volcano (p. 256) – A mountain formed of lava and/or pyroclastics.