Earth Science Flashcards
Astronomy
the study of the universe beyond Earth’s atmosphere
Asteroids
minor planets sometimes called planetoids
Comets
small bodies of gas and dust consisting of a nucleus of ice and dust, a coma of gas and dust, and the tail (also gas and dust) that is only visible when the comet approaches the sun
Meteors
any matter that collides with the Earth
Meterology
the study of Earth’s atmosphere and its changes and interaction with the ground
Evaporation
Water on Earth is constantly turning to vapor in
a process called
Condensation
When warm air becomes saturated, or full of moisture, the water forms droplets
Geology
the study of the origin, structure, and composition
of the Earth
Cenozoic Era
began about 65 million years ago.
Giant glaciers (slow-moving sheets of ice)
retreated from land masses allowing mammals
and flowering plants the opportunity to diversify.
We are still in the Cenozoic era today.
Precambrian Era
oldest era; a time of massive volcanic
activity
Paleozoic Era
570 million years ago; the emergence
of continents and mountains
Mesozoic Era
225 million years ago; more volcanic eruptions; also known as “The Age of Reptiles”
(time of dinosaurs)
Plate tectonics
the study of the movement
of large chunks or plates of the Earth’s crust.
Igneous rocks
formed by the crystallization of magma,
or molten lava. An example is granite.
Sedimentary rocks
formed by the accumulation of silt or other rock fragments. Limestone is an example.
Metamorphic rocks
formed when pre-existing rock is subjected to chemical or physical alteration by high heat and pressure. An example is marble.
Mantle convection
occurs because the density of a fluid is related to its temperature. Hot rocks lower in the mantle are less dense than their cooler counterparts above. The hot rock rises and the cooler rock sinks due to gravity. This process is the origin of crustal plate movement.
Radioactive Dating
Measurement of the amount of radioactive material (usually carbon 14) that an object contains; can be used to estimate the age of the object based on a measure of radioactive decay / also called radiometric or carbon dating
Mineral content
The mineral formations contained in a rock; examination of mineral content does not make it possible to accurately determine the age of a rock since minerals can sit for long periods with little change after formation
Law of Superposition
Layers of rock are arranged in a time sequence, with the oldest on the bottom and the youngest on the top; later processes can disturb the arrangement thus making it difficult to determine age of a single rock sample
Crystal analysis
Determines the arrangements of atoms in solids; crystal formation, like mineral content, does not help accurately determine the age of a rock since crystals can sit for long periods with little change after formation
Oceanic ridge
an underwater mountain range, formed when convection
currents rise in the mantle beneath the oceanic crust
and create magma where two plates meet at a
divergent boundary.
Oceanic trench
a hemispheric-scale long but narrow topographic depression of the sea floor caused by plates moving together along convergent boundaries
Mohs Hardness Scale
The Mohs scale was devised by Friedrich Mohs in 1812 and has been a valuable aid to identifying minerals ever since. Here are the ten standard minerals in the Mohs scale: 1. Talc 2. Gypsium 3. Calcite 4. Fluorite 5. Apatite 6. Feldspar 7. Quartz 8. Topaz 9. Corundum 10. Diamond
Exosphere
upper limit of our atmosphere
Thermosphere
very thin. It’s where the space shuttle orbits.
Mesosphere
Rock fragments from space burn up
Stratosphere
Many airplanes fly in the Stratosphere because it is very stable. Also, the ozone layer is there. Temperature increase
Troposphere
closest to the Earth where weather occurs.
Cumulus clouds
puffy white or light gray clouds that look like floating cotton balls. Cumulus clouds have sharp outlines and a flat base.
Cumulonimbus clouds
generally known as thunderstorm clouds. They form when warm, moist air rises quickly in the atmosphere.
Stratus clouds
uniform gray in color and almost cover the entire sky. Light mist or drizzle is sometimes associated with them.
Stratocumulus clouds
low, lumpy, gray, and but bring little or no precipitation.
Nimbostratus clouds
dark gray with a ragged base and are associated with continuous light rain or snow.
Altostratus clouds
cover the whole sky and have a gray or blue-gray appearance. They usually form ahead of storms. Sometimes rain will fall from altostratus clouds.
Altocumulus clouds
grayish-white with one part of the cloud darker than the other. They usually form in groups. If you see Altocumulus clouds on a warm humid morning, then expect thunderstorms by late afternoon.
Cirrus clouds
composed entirely of ice and consist of long, thin, wispy streamers. They are white and predict fair weather.
Cirrostratus clouds
thin clouds that usually cover the entire sky. They often come 12-24 hours before a rain or snow storm.
Cirrocumulus clouds
small rounded puffs that appear in long rows. They are usually white, but can appear gray and are usually seen in the winter time and indicate fair, but cold weather.
