term 2 sci exam block Flashcards
what are minerals?
Combination of substances and chemical properties that form together
how do geologists identify rocks?
The hardness, lustre (how shiny), transparency, shape of crystals, density, streak (powder of mineral)
What is hardness?
how easy it is to scratch the rock
what is streak?
The colour of the crushed mineral
how are igneous rocks formed
there are intrusive and extrusive igneous rocks. Intrusive rocks are formed when magma chamber for pockets of magma and then the magma hardens over a long period of time. Extrusive rocks are formed when the lava hardens very quickly and forms into rock.
What is a sedimentary igneous rock?
When there are layers of sediments compacted together, water seeps in with chemicals in the water. The water evaporates leaving chemicals, having the chemical be like glue forming a sedimentary rock
What are the different Sedimentary Rocks?
chemical-dissolved minerals left behind when water evaporates creating another rock
Organic- formed from remains of living things
Clastic- formed when rock fragments are deposited, compacted and cemented
What are metamorphic rocks?
Rocks formed when the heat or pressure of the Earth change the rock from its original form
what are the bands of a metamorphic rock?
It tells us how the crystals were squeezed into the new crystal some even melted.
what is the process of the rock cycle?
1 magma/lava = igneous rocks
2 rocks brought up from tectonic plates
3 on surface rocks weathered
4 weathered particles removed by erosion, transported=deposited
5 deposited sediments or eroded form layers, sedimentary rocks
6 Earths heat and pressure =metamorphic
7 if too much heat or pressure goes to magma and cycle starts again
what are foliated and non-foliated metamorphic rocks?
foliated- have banded material, looks layered, when broken thin rock fragments show
Non-foliated- no obvious banding, granular, no layers fall apart when broken
What are some metamorphic rocks?
limestone= marble Shale = slate Sandstone= quartzite
what are some sedimentary rocks?
mudstone, sandstone, limestone
what are some Igneous rocks
Granite= intrusive, obsidian = extrusive, Pumice= extursive, Basalt= extrusive
What are the Earth’s layers?
inner core and outer core= solid
Mantle, lithosphere, asthenosphere= liquid
Crust= solid
What are convection currents?
Core is very hot meaning that the particles rise. Then when they get to the upper part of the mantle they cool down a bit meaning the become dense. The particles fall down and start cycle again.
What do convection currents do to the tectonic plates?
the Convection currents rising and falling underneath the tectonic plates causing the plates to shift. The tectonic plates create gaps and filling it with magma making igneous rocks.
What is a Transform boundary?
when two tectonic plates build up pressure and slide next to each other.
What are converging boundaries?
when two tectonic plates go towards each other forcing the land to go upwards because of all the pressure moving upwards
what are diverging boundaries?
when two tectonic plates moving away from each other in opposite directions
What is an ocean to continent collision?
When a tectonic plate on land and one from the sea converge into each other causing the denser plate to subduct. This is the oceanic plate because it is denser
what is ocean-to-ocean collision?
When the oceanic crusts both collide into each other having the denser plate go underneath the less dense plate.
What is continent- to-continent collision?
When two continent plates converge and since they are the same densities they push the land upwards creating mountains etc.
What is Pangeaa?
When the continents were all together like a puzzle millions of years
