Science Flashcards
Give examples of Igneous rocks
- Granite (intrusive inside volcano)
- Basalt (extrusive outside volcano)
- Pumice is an unusual, lightweight rock formed when molten rock is rapidly blown out of a volcano, forming bubbles as it quickly loses pressure and cools at the same time.
- Obsidian is a volcanic glass that forms quickly without crystal growth, it can have very sharp edges making it useful as a cutting tool or arrowhead.
What is magma?
Hot melted liquid inside earth
What is lava?
Hot melted liquid that has erupted from the earth and is outside.
Name the three main types of rock
Igneous
Metamorphic
Sedimentary
What are sedimentary rocks?
Sedimentary rocks are formed by sediment that is deposited over time, usually as layers at the bottom of lakes and oceans.
The sediment has been compressed.
What are sedimentary rocks made up of?
minerals, small pieces of plants and other organic matter.
Name some sedimentary rocks
limestone, sandstone, chalk, coal, claystone and flint.
What is limestone made of?
Shells and fish scales
What is sandstone made of?
Sand
What is coal made of?
Trees and plants
What is a metamorphic rock?
Metamorphic rocks have been changed over time by extreme pressure and heat.
How are metamorphic rocks formed?
Metamorphic rocks can be formed by pressure deep under the Earth’s surface,
from the extreme heat caused by magma or
the intense collisions and friction of tectonic plates.
Name some metamorphic rocks
quartzite, marble, slate, granulite, gneiss and schist.
How is marble formed?
Marble is a metamorphic rock that is formed from the sedimentary rock limestone.
How is slate formed?
Slate is a metamorphic rock that is formed from the sedimentary rock mudstone or clay.
What is the rock cycle?
The rock cycle is a basic concept in geology that describes the dynamic transitions through geologic time among the three main rock types: sedimentary, metamorphic, and igneous.
How is obsidian formed?
Sometimes, when cool, sticky magma erupts, the lava solidifies too rapidly for crystals to form and so volcanic glass (obsidian) is produced.
How is granite formed
If magma is trapped underground in an igneous intrusion, it cools slowly because it is insulated by the surrounding rock. Crystals have more time to grow into large crystals
How is basalt formed?
when basalt lava erupts from a volcano, then many crystals form very quickly, and the resulting rock is fine-grained, with crystals usually less than 1mm in size.
How does the cooling rate of igneous rocks affect their crystal size?
The slower they cool the larger the crystals.
What is an IGNEOUS rock?
A rock formed by the action of fire
What is hardness?
its ability to resist scratching.
Where did the hardness scale originate?
Friedrich Mohs, a German mineralogist, developed a hardness scale over 100 years ago. The hardest mineral known, diamond, was assigned the number 10.Hardness Scale
Index Mineral
Common Objects
1 Talc 2 Gypsum Fingernail 3 Calcite 4 Fluorite Copper Penny 5 Apatite Glass 6 Orthoclase 7 Quartz 8 Topaz 9 Corundum 10 Diamond
What is streak?
The streak of a mineral is the color of the powder left on a streak plate (piece of unglazed porcelain) when the mineral is scraped across it. The streak plate has a hardness of glass, so minerals with a Mohs Hardness >7 will scratch the streak plate and won’t powder the mineral.
What are the properties of minerals?
Hardness
Colour
Streak
Crystals
Define COLOUR of minerals
What causes color in minerals?
Minerals are colored because certain wave lengths of light are absorbed, and the color results from a combination of those wave lengths that reach the eye.
Define crystals
Mineral crystals occur in various shapes and sizes. The particular shape is determined by the arrangement of the atoms, molecules or ions that make up the crystal and how they are joined
Define cleavage
Cleavage & Fracture
Minerals tend to break along lines or smooth surfaces when hit sharply. Different minerals break in different ways showing different types of cleavage.
Name the six layers of the earths structure
Crust Mantle Outer core Inner core Asthenosphere Lithosphere
Provide 3 points about the crust
The crust is the outer layer of the earth.
It is a thin layer between 0-60 km thick.
The crust is the solid rock layer upon which we live.
3points about the mantle
The mantle is the widest section of the Earth.
It has a thickness of approximately 2,900 km.
made up of semi-molten rock called magma.
In the upper parts of the mantle the rock is hard, but lower down the rock is soft and beginning to melt.
3 points about the outer core
The outer core is the layer surrounding the inner core.
It is a liquid layer,
made up of iron and nickel.
It is still extremely hot, with temperatures similar to the inner core.
3points about the inner core
The inner core is in the centre and is the hottest part of the Earth.
It is solid and made up of iron and nickel with temperatures of up to 5,500°C.
With its immense heat energy, the inner core is like the engine room of the Earth.
3points about the lithosphere
The lithosphere is the rocky outer part of the Earth. It is made up of the brittle crust and the top part of the upper mantle. The lithosphere is the coolest and most rigid part of the earth.
What is the asthenosphere?
The upper part of the Earth’s mantle, extending from a depth of about 75 km (46.5 mi) to about 200 km (124 mi).
The asthenosphere lies beneath the lithosphere and consists of partially molten rock. Seismic waves passing through this layer are significantly slowed.
What is weathering?
What is erosion?
Weathering is the process where rock Larry is dissolved, worn away or broken down into smaller and smaller pieces. There are mechanical, chemical and organic weathering processes.
Erosion - 2.
the process by which the surface of the earth is worn away by the action of water, glaciers, winds, waves, etc.
What is chemical weathering?
Chemical weathering decomposes or decays rocks and minerals. An example of chemical weathering is waterWilliam dissolving limestone.
Define sediment?
Define sedimentation?
Sediment -mineral or organic matter deposited by water, air, or ice.
Sedimentation-the deposition or accumulation of sediment.
What is deposition?
Deposition is the geological process in which sediments, soil and rocks are added to a landform or land mass. Wind, ice, and water, as well as sediment flowing via gravity, transport previously eroded sediment, which, at the loss of enough kinetic energy in the fluid, is deposited, building up layers of sediment.
What is stratification ?
Cementing?
stratification definition. The process by which materials form or are deposited in layers, as in sedimentary rocks and
Define concretion ?
Concretion-the act or process of concreting or becoming substantial; coalescence; solidification.
What is the law of super position ?
of stratigraphy, or the study of geological or soil layers.
Steps in fossil formation
Fossils are formed in a number of different ways, but most are formed when a plant or animal dies in a watery environment and is buried in mud and silt. Soft tissues quickly decompose leaving the hard bones or shells behind. Over time sediment builds over the top and hardens into rock.
