Chapter 8 Earth's History Prentice Hall California Life Science

students know earth process today are similar to those that occurred in

the past and slow geologic processes have large cumulative effects over long periods of time

Students know the history of life on earth has been disrupted by MAJOR events such as

Catastrophic events 1.Major Volcanic eruptions or the 2. impact of Asteroids

Rock cycle includes the formation of new sediment and the rocks and the rocks are often found in

Layers with the oldest generally found on the bottom, think of the end of the book being farther from the start.

Evidence from " 1" and "2" indicates the earth is approximately ? old and life on this Planet existed for more than ? years?

Geologic layers and radioactive dating
Earth is 4.6 Billion years old.
Life on Earth is more than 3 Billion years old.

Movements of Earth's (1) and (2) Through time, with associated changes in climate and geographic connections, have

affected the past and present distribution of organisms.

What is relative age?

it relates to the age of something else that is compared to.

Geology

Study of structure of earth, the forces that make and shape it.

erosion

Occurs when running water, ice, or wind break down rocks and carry the pieces away. Hutton concluded these same processes occurred a long time ago.

uniformitarianism

KEY FACTOR, the principle of ( ) states GEOLOGIC PROCESSES THAT OPERATE TODAY ALSO OPERATED IN THE PAST.

ingenous rock

FORM WHEN MOLTEN MATERIAL BENEATH EARTH'S SURFACE COOLS AND HARDENS. MAY FORM BELOW THE EARTH'S SURFACE.

metamorphic rock

CHANGE" IS IN THE WORD, forms when an existing rock is changed by heat, pressure, or chemical reactions. Most form under pressure DEEP underground.

rock cycle KEY POINT

FORCES INSIDE EARTH AND AT THE SURFACE PRODUCE A ROCK CYCLE THAT BUILDS, CHANGES AND DESTROYS ROCKS.

magma

Molten material beneath the surface, as it is forced toward the surface, it may form a volcanic mountain. If it hardens before reaching the surface it becomes igneous rock such as BASALT OR GRANITE think plates, but if it flows to the surface as a liquid

lava

rock that in its molten form (as magma) issues from volcanos - NOT IN A ROCK STATE!!!!

Sedimentary rock

A type of rock that forms when particles from other rocks or the remains of plants and animals are pressed and cemented together

relative age

the age of something compared with other things, the age of rock compared to the ages of other rocks

absolute age

The age of a rock given as the number of years since the rock formed.

law of superposition

The geologic principle that states that in horizontal layers of sedimentary rock, each layer is older than the layer above it and younger than the layer below it.

extrusion

squeezing out by applying pressure

intrusion

the forcing of molten rock into fissures or between strata of an earlier rock formation

fault

(geology) a crack in the earth's crust resulting from the displacement of one side with respect to the other

unconformity

where there is gap in the rock layers, a break in the geologic record created when rock layers are eroded or when sediment is not deposited for a long period of time

inclusion

a piece of rock that is contained in another rock; it is always younger than the rock containing it

index fossil

a fossil known to have lived in a particular geologic age that can be used to date the rock layer in which it is found

atom

(physics and chemistry) the smallest component of an element having the chemical properties of the element

element

an artifact that is one of the individual parts of which a composite entity is made up

radioactive delay

exhibiting or caused by radioactivity

half-life

the time required for one half of the atoms of a radioisotope to emit radiation an decay products

plate

a rigid layer of the Earth's crust that is believed to drift slowly

theory of plate tectonics

State that Earth's lithosphereis broken into huge, moving slabs of rock driven by motions in the mantle

continental drift

the gradual movement and formation of continents (as described by plate tectonics)

geologic time scale

scale used by paleontologists to represent evolutionary time

era

a major division of geological time

period

a unit of geological time during which a system of rocks formed

invertebrate

lacking a backbone or spinal column

vertebate

animal with a backbone

amphibian

cold-blooded vertebrate typically living on land but breeding in water

reptile

any cold-blooded vertebrate of the class Reptilia including tortoises turtles snakes lizards alligators crocodiles and extinct forms

mass extinction

event in which many types of living things become extinct at the same time

mammal

any warm-blooded vertebrate having the skin more or less covered with hair

KEY POINT WHAT 3 TYPES OF GROUPS DO GEOLOGISTS CLASSIFY ROCKS INTO?

SIM
IGNEOUS, SEDIMENTARY, METAMORPHIC