Chapter 1: Intro to Earth Science

Earth Science

the name for all the sciences that collectively seek to understand Earth and its neighbors in space.

Historical Geology

to understand the origin of Earth and the development of the planet through its 4.6-billion-year history. It strives to establish an orderly chronological arrangement of the multitude of physical and biological changes that have occurred in the geologic past.

Oceanography

the study of the composition and movements of seawater, as well as coastal processes, seafloor topography, and marine life.

Geologic Time

the span of time since the formation of Earth

Scientific Method

The process just described, in which researchers gather facts through observations and formulate scientific hypotheses and theories

Hydrosphere

a dynamic mass of water that is continually on the move, evaporating from the oceans to the atmosphere, precipitating to the land, and running back to the ocean again.

Biosphere

includes all life on Earth

Geosphere

extends from the surface to the center of the planet, a depth of 6400 kilometers [4000 miles], making it by far the largest of Earth's four spheres.

Continental Drift

the idea that the continents move about the face of the planet.

Lithospheric Plates

Earth's rigid outer shell (the lithosphere) is broken into numerous slabs

Transform Boundaries

This is when plates do not push together or pull apart. Instead, they slide past one another, so that seafloor is neither created nor destroyed.

Continent

remarkably flat features that have the appearance of plateaus protruding above sea level. The continents average about 35 kilometers in thickness and density of 2.7 g/cm3

Ocean Basin

bowl-shaped depression in the earth, with complex topography along its deep seafloor. The basaltic rocks that comprise the oceanic crust average only 7 kilometers (5 miles) thick and have an average density of about 3.0 g/cm3 .

Mountain Belts

a group of mountain ranges with similarity in form, structure, and alignment that have arisen from the same cause, usually an orogeny.

Craton

is an old and stable part of the continental lithosphere

Continental Margins

is the portion of the seafloor adjacent to major landmasses. It may include the continental shelf, the continental slope, and the continental rise.

Continental Shelf

a gently sloping platform of material that extends seaward from the shore.

Continental Slope

boundary between the continents and the deepocean basins and a relatively steep dropoff that extends from the outer edge of the continental shelf to the floor of the deep ocean

Abyssal Plains

incredibly flat features of deep-ocean basins

Deep-ocean trenches

The ocean floor also contains extremely deep depressions that are occasionally more than 11,000 meters (36,000 feet) deep.

Seamounts

Dotting the ocean floor are submerged volcanic structures which sometimes form long, narrow chains.

Earth system science

aims to study Earth as a system composed of numerous interacting parts, or subsystems.

System

a group of interacting, or interdependent, parts that form a complex whole.

Geology

the study of the Earth, the materials of which it is made, the structure of those materials, and the processes acting upon them.

Astronomy

the study of the universe

Hypothesis

a tentative (or untested) explanation, and a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation

Convergent Boundaries

Where two plates move together one of the plates plunges beneath the other and descends into the mantle

Divergent Boundaries

Plate tectonic boundary where lithospheric plates are moving apart.

Shields

which are expansive, flat regions composed of deformed crystalline rock.

Continental Rise

a thick accumulation of sediments that moved downslope from the continental shelf to the deep-ocean floor.

Hydrologic Cycle

It represents the unending circulation of Earth's water among the hydrosphere, atmosphere, biosphere, and geosphere.

Rock Cycle

The loop that involves the processes by which one rock changes to another

Physical Geology

examines the materials composing Earth and seeks to understand the many processes that operate beneath and upon its surface

Meteorology

the study of the atmosphere and the processes that produce weather and climate.

Natural Hazards

physical phenomena caused by atmospheric, water or tectonic processes that threaten people, property or the environment. They can occur within a short or long period of time.

Resources

represent another important focus that is of great practical value to people. They include water and soil, a great variety of metallic and nonmetallic minerals, and energy

Theory

a carefully thought-out explanation for observations of the natural world that has been constructed using the scientific method, and which brings together many facts and hypotheses.

Atmosphere

made of the layers of gases surrounding a planet or other celestial body.

Plate Tectonics

a theory explaining the structure of the earth's crust and many associated phenomena as resulting from the interaction of rigid lithospheric plates which move slowly over the underlying mantle.

Stable platforms

Other flat areas of the stable interior exist in which highly deformed rocks, like those found in the shields, are covered by a relatively thin veneer of sedimentary rocks.

Deep-ocean basins

Between the continental margins and oceanic ridges

Oceanic ridges

the most prominent feature on the ocean floor and this broad elevated feature forms a continuous belt consists of layer upon layer of igneous rock that has been fractured and uplifted.