module 4: geology Flashcards
A dynamic planet and constantly changing structure.
A layered sphere.
Earth
interior, is composed of a dense, intensely hot mass of metal, mostly iron, thousands of kilometers in diameter.
Core
surrounding the molten outer core. It is a hot, pliable layer of rock.
Mantle
the cool, lightweight, brittle rock outermost layer of the earth
Crust
publish a sketch showing how the two continents could fit together, jigsaw-puzzle fashion.
Antonio Snider
Climatologist, was struck not only by the matching coastlines, but by geologic evidence from the continents.
Alfred Wegener
may preserve evidence of the ancient climate of the time and place in which the sediments were deposited.
Sedimentary rocks
There are evidences of extensive glaciation in places now located in the tropics
parts of Australia, southern Africa, and South America.
There are coal deposits
Antarctica
fossil plant, remains of which are found in limited areas of widely separated lands
Glossopteris
fossils of a small reptile, similarly dispersed across two continents.
Mesosaurus
the modern continents moving to their present positions via a process
continental drift
study of large scale movement and deformation of the earth’s outer layers
Tectonics
such deformation to the existence and movement of rigid “plates” over a weaker, more plastic layer in the earth’s upper mantle
Plate tectonics
The earth’s crust and uppermost mantle are somewhat brittle and elastic
Lithosphere
meaning “without strength”,
Its lack of strength or rigidity results from a combination of high temperatures and moderate confining pressures that allows the rock to flow plastically under stress.
Asthenosphere
The distribution of earthquakes and volcanic eruptions indicates that these phenomena are far from uniformly distributed over the earth.
Locating Plate Boundaries
lithospheric plates MOVE APART
Divergent plate boundary
most common type of divergent boundary worldwide, and it is already noted the formation of new oceanic lithosphere at these ridges.
SEAFLOOR SPREADING RIDGES
plates are MOVING TOWARD EACH OTHER
Convergent plate boundary
This type of plate boundary, where one plate is carried down below (subducted beneath) another
subduction zone
At an ocean-ocean convergence, the result is commonly a line of volcanic islands
island arc
are frequent during continent-continent collision as a consequence of the large stresses involved in the process
Earthquakes
ridges consist of many short segments slightly OFFSET from one another
Transform Boundaries
The offset is a special kind of fault, or break in the lithosphere
transform fault
naturally occurring, inorganic, solid element or compound with a definite chemical composition and a regular internal crystal structure
mineral
not produced solely by living organisms or by biological processes
Inorganic
materials are solids in which the atoms or ions are arranged in regular, repeating patterns.
Crystalline
The two fundamental characteristics of a mineral that together distinguish it from all other minerals are its
chemical composition and its crystal structure
A mineral’s composition and crystal structure can usually be determined only by
using sophisticated laboratory equipment.
the largest compositional group of minerals
SILICATES
Two most common elements in the earth’s crust are
silicon and oxygen
probably the best known silicate. Compositionally, it is the simplest, containing only silicon and oxygen.
Quartz
The most abundant group of minerals in the crust
Feldspars
The general term used to describe those silicates that contain iron and/or magnesium, with or without additional elements.
Ferromagnesian
simple ferromagnesian mineral, is a major constituent of earth’s mantle
Olivine
sheet silicates, built on an atomic scale of stacked-up sheets of linked silicon and oxygen atoms
Micas
the sheets tend to slide past each other, a characteristic that contributes to the slippery feel of many clays and related minerals
Clays
mineral group is defined by some chemical constituent or characteristic that all members of the group have in common
NONSILICATES
is a solid, cohesive aggregate of one or more minerals, or mineral materials
rock
The three broad categories of rocks
igneous, sedimentary, and metamorphic
a rock formed by the solidification and crystallization of a cooling magma.
IGNEOUS ROCK
the name given to naturally occurring hot, molten rock material
Magma
the most widely known example of a plutonic rock
Granite
are loose, unconsolidated accumulations of mineral or rock particles that have been transported by wind, water, or ice, or shifted under the influence of gravity, and redeposited
Sediments
When sediments are compacted or cemented together into a solid, cohesive mass
- formed at low temperatures
sedimentary rocks
set of processes by which sediments are transformed into rock
lithification
Formed from the products of the mechanical breakup of other rocks.
Clastic sedimentary rocks
composed mostly of calcite
Limestone
made up of the mineral halite
Rock salt
one that has formed from another, preexisting rock that was subjected to heat and/or pressure.
METAMORPHIC ROCKS
Heat and pressure commonly cause the minerals in the rock to
recrystallize
metamorphosed shale that has developed foliation under stress
Quartzite
a schematic view. Basically, a variety of geologic processes can transform any rock into a new rock of the same or a different class
rock cycle
the study of resources that are valuable for manufacturing
Economic mineralogy
An ancient method of accumulating gold, diamonds, and coal is
placer mining
minerals are a broad class that covers resources from silicate minerals
Nonmetals
Another ancient, and much more dangerous, method is
underground mining
roasting ore to release metals—is a major source of air pollution
Smelting
sudden movements in the earth’s crust that occur along faults
Earthquakes
giant sea waves triggered by earthquakes or landslides
Tsunamis
general term for rapid downslope movement of soil or rock
Landslide
occurs on all sandy shorelines because the motion of the waves is constantly redistributing sand and other sediments
Beach erosion
refers to atmospheric conditions that occur locally over short periods of time
Weather
refers to the long-term regional or even global average of temperature
Climate
Warming that result when the atmosphere traps heat radiating from Earth toward space
Greenhouse Effect
Gases that contribute to the greenhouse effect include:
➢ Water vapour
➢ Carbon Dioxide
➢ Methane
➢ Nitrous Oxide
➢ Chlorofluorocarbons
The long-term heating of Earth’s climate
Global Warming
A long-term change in the average weather patterns
Climate Change
