Chapter 1

Question 1

Asthenosphere

Answer 1

A part of Earth’s layers. Right underneath the Lithosphere and 2nd layer out of 4. Made of liquid peridotite.

Question 2

Closed system

Answer 2

Energy moves freely in and out. Matter does not enter or leave the system.
– E.g. Earth

Question 3

Core

Answer 3

The central or innermost portion of the Earth, lying below the mantle and probably consisting of iron and nickel. It is divided into a liquid outer core, which begins at a depth of 2,898 km (1,800 mi), and a solid inner core, which begins at a depth of 4,983 km (3,090 mi).

Question 4

Crust

Answer 4

In geology, a crust is the outermost layer of a planet. The crust of the Earth is composed of a great variety of igneous, metamorphic, and sedimentary rocks. The crust is underlain by the mantle.

Question 5

Hypothesis

Answer 5

A tentative or untested explanation.

Question 6

Igneous rock

Answer 6

Formed from cooling and solidification of magma (molten rock).
– E.g. Granite and basalt

Question 7

Inner core

Answer 7

Extends from 5,100 km depth to the center of the Earth. Composed mostly of solid iron and nickel

Question 8

Lithosphere

Answer 8

Includes crust and solid upper portion of mantle.

Question 9

Mantle

Answer 9

Is solid all the way down to the Outer Core. Lower mantle composed of a high- density, Mg-silicate rock called perovskite.

Question 10

Metamorphic rock

Answer 10

Formed by “changing” preexisting igneous, sedimentary, or other metamorphic rocks. Driving forces are increased heat and pressure.
– E.g. Gneiss and marble

Question 11

Mid-ocean ridge

Answer 11

An elevated region with a central valley on an ocean floor at the boundary between two diverging tectonic plates where new crust forms from upwelling magma.

Question 12

Nebular hypothesis

Answer 12

Solar system began as a giant rotating cloud of gas and dust called the solar nebula:
– Nebula composed mostly of hydrogen and helium;
– Rotating nebula began to contract about 5 billion
years ago;
– Developed into a flat, disk shape with the proto-Sun (pre-Sun) at the center;
– Inner planets formed from metallic and rocky
substances;
– Larger outer planets formed from fragments of ices (H2O, CO2, NH3 and CH4) that accumulated around rocky cores.

Question 13

Open system

Answer 13

Energy and matter flow into and out of system.

– E.g. The ocean

Question 14

Outer core

Answer 14

2nd to the farthest layer of the Earth. Consists mainly of molten (liquid) iron. Source of Earth’s magnetic field.

Question 15

Planets

Answer 15

Terrestrial planets:
– Closest to the Sun;
– Generally small, rocky bodies with densities greater than 3gm/cm3;
– Composed mainly of silicates, Fe and Ni Volcanism mostly basaltic.

Jovian (giant) planets:
– Each has solid rocky core surrounded by layers of frozen or liquid hydrogen, helium, methane, and ammonia;
– Multiple moons;
– Impressive ring systems composed of dust- to boulder-sized particles of mostly ice.

Question 16

Relative dating

Answer 16

Geologic events and materials are placed in their proper sequence or order of occurrence without knowing their ages.

Question 17

Rock cycle

Answer 17

The loop that involves the processes by which one rock changes to another.
Magma, igneous, sediment, sedimentary rock, metamorphic rock, back to magma.

Question 18

Sedimentary rock

Answer 18

Sediments are derived from weathering of preexisting rock. They accumulate as layers at Earth’s surface. Buried sediments are converted into rocks.
– E.g. Sandstone and limestone

Question 19

Solar nebula

Answer 19

A large cloud of gas and dust from which the sun, planets, and other solar system bodies formed.

Question 20

System

Answer 20

Any size group of interacting parts that form a complex whole.
– E.g. Cooling system in cars, nervous system in animals.

Question 21

Theory

Answer 21

A well tested and widely accepted view that scientists agree best explain certain observational facts.