Prüfung Flashcards
Which rock types are the bright areas on the moon and how did they form?
Granite, plutonite, light colour because of minerals, lower cyrstallisation temperatur
What happens when continents collide?
Continental collision is a phenomenon of the plate tectonics of the earth that occurs at convergent boundaries. Continental collision is a variation on the fundamental process of subduction
Subduction zone destroyed
mountains produced
continents nurtured together
Name 4 official timeunits which are still ongoing today
- Phanerozoikum,
- Känozoikum,
- Quartär,
- Holozän
name 2 energy sources inside the Earth
- Primoridal heat,
- Gravitational energy (+ Radioactive Decay In The Mantle)
Name 3-4 official timeperiods which are in the past (- today)
- Kreide,
- Jura,
- Trias,
- Pilozän,
- Eozönm,
- Mesozoikum,
- Paläozoikum
Convection inside the earth: which type of energy is convection?
Energy that moves, it rises hot air masses from bottom to the surface of earth
5 structure types of silicate minerals
- isolated tetrahedra,
- chain of tetrahedra,
- double chain of tetrahedra,
- sheet of tetrahedra,
- complex three-dimensional network.
Definition of the magnitude on the richter scale?
Max. amplitude of the first seismic wave in 100 km distance from the epicentre. The scale logarithmic, meaning that each increase of one unit means a ten-fold amplification of the quake. Therefore large increase in damage only a few tenths increase in magnitude can occur.
Direct and indirect dangers of volcanoes?
direct: air fall, pyroclastic flow, CO2 lakes, lava flow
indirect: lahars, tsunamis, earthquakes, landslides
Direct and indirect dangers of earth quakes?
Direct: Groundmotion, Dislocation of the surface topography
Indirect: Fire, Liquefaction, Tsunamis, Landslides
What is the main source of heat on the surface of earth?
The sun
Which are the two main sources of heat on Earth?
Exogenous source: the sun.
Endogenous source: interior of the earth:
primordial heat – a leftover from the formation of the earth and its core.
gravitational contraction causes the Earth to decrease in volume and become denser, increasing the temperature in the process.
radioactive decay of isotopes in mantle and crust releases thermal energy.
What are 2 reasons for different density in the ocean?
- Salinity
- temperature
Name and describe 4 stages of the formation and development on earth
1) solar fog: accumulation of particles through gravitation, heat increase and rising gravity. Result: primitive Earth.
2) formation of core and mantle: heavy elements move to the centre, metals sink, silicates rise. Result: differentiated Earth.
3) mantle-crust-fractionation: basaltic magma formed through partial melting of primitive mantle. Result: developed Earth.
4) inter-crustal-differentiation: partial melting of lower crust, granitic melts rise into upper crust.
Result: modern Earth
Name and describe the three basic types of rocks.
igneous rock: formed from magma cooling slowly in the interior of the earth; due to the slow cooling, a crystalline structure can develop (intrusive igneous rocks). If magma cools rapidly,
volcanic rock (extrusive igneous rock) is formed – due to the fast cooling process, less or no crystals can form (like basalt).
metamorphic rock: formed through the change of igneous or sedimentary rocks due to pressure or temperature.
sedimentary rock: formed through the solidification of sediments; can be formed from organic remains (limestone) or from the cementing of other rocks
Which factor determines the type of soil that forms in a certain region?
Soil types depend on the original rock they form from/on; thereby rocks influence the agricultural or sylvicultural use of a region. limestone – rendzina sandstone – podzona loess – chernozem gneiss/shale – brown earth
Name five differences between basalt and granite
Basalt: Volcanite 50% quarzpart High density High Temp- Dark
Granite: plutonite 70% quarzpart low density low Temp light
Which process creates the magnetic field of the Earth? How can the magnetic field be used to reconstruct the formation of the ocean floor?
The convection current in the outer core causes the magnetic field. This magnetic field reverses from time to time, which offers the opportunity to date ocean floor. Certain atoms (for example atoms of magnetite) will face the direction of the magnetic north pole during rock formation and will stay in this position after the rock cooled down. Thereby a symmetric pattern on both sides of an MOR is created. With a lot of data and comparisons, this pattern can be used to date the material of the ocean floor.
Name the energy transport from the inner Earth to the Litosphere?
Convection
Name the energy transport from the inner Earth to surface?
Conduction
What is the normal geothermic gradient?
3 °C / 100 meters
Which mineral is basaltic magma and hydrolythic magma?
Basaltic: Olivine, Gabbro, Periodit
Hydrolythic: Granit, Quarz
Which two factors influence the sea-level?
eustatic oscillations: internal changes (in the ocean)
variation of surrounding land masses: subsidence, uplift, artificial removal of ground water, etc
Which factors influence the density of sea water and which three zones are
distinguished in the ocean?
Salinity and temperature define the density of the water.
Zones: − surface layer − thermocline, halocline, pycnocline − deep zone
Which two main processes induce deep water masses formation inside of recent oceans?
- Organisms like planktons create sediments,
- material from slopes slides to the oceans
What is the main rock type of the oceanic crust?
Basalt
How does heat flow in the inside of the earth?
Convection currents (heat transport through movements) in the plastic parts of the geosphere (outer core, mantle, asthenosphere) transport heat from the core towards the surface. Convection inside the mantle is one of three driving forces causing tectonic movement and it causes the magnetic field of Earth. In the solid parts (lithosphere, crust) conduction (heat transport without movement) takes place.
What is the reason for heat transport inside the earth?
Convection
Witch energy is causing the convection in Earth?
Gravitation, because it’s the reason for the heat in the inner core through pressure. And with the high pressure, you also got the density. And convection are caused by temperature differences.
What happen in the Mantel?
Convection, but here the heat is provided by the outer core and not the inner core (like in the case of the convection of the outer core)
What is the main source of heat on the surface of earth?
Sun
Witch are the two main sources of heat inside of the earth?
Primordial heat, Gravitational energy (+ Radioactive Decay In The Mantle)
Explain the terms endogenous and exogenous.
endogenous dynamics: caused by internal energy; relief elevating processes. Tectonics, magnetism, metamorphism, composition and movements of Earth.
exogenous: caused by external energy input (sun); relief decreasing processes. Weathering, water cycle, climate zones, oceans, sediments.
Name and describe the three types of plate boundaries.
Divergent: plates move apart from each other and new lithosphere is formed in the process.
Transform: plates slide past each other.
Convergent: plates move towards each other; either the lithosphere is subducted into the mantle, or the plates collide and their edges are compressed, folded and uplifted.
What happens, when plates collide?
Creation of hills, subduction, grinding
tectonics meaning
movement of the Earth and the consequential creation of minerals
which plate boundary type is the most dangerous concerning earthquakes?
Convergentplate boundaries
what do the crosshatched areas mean on the map?
These are the areas where a high risk of environmental disasters are (earthquakes, volcanoes, tunamis …)
Name the 7 most important tectonic plates
Big ones: African plate, Australian-Indian plate, Eurasian Plate, American plate, Antarctica plate,
Pacific plate, Nazca plate
What is a mid-ocean-ridge?
An underwater mountain system formed by plate tectonics; consists of mountains linked in chains; is the result of seafloor-spreading and is found at divergent plate boundaries. As they are located on plate boundaries, these zones show a lot of geological activity in the form of volcanism and seismicity.
Name the three different types of magma.
andesitic magma: formed out of melting plates; the subducting plate consists of basalt and water, which results in very gaseous magma.
basaltic magma: comes from the mantle; can break through the earths surface due to high temperature.
Rhyolites: formed in the continental crust; usually rich in water and containing CO2
Where are volcanoes typically found?
They are usually found where tectonic plates are either diverging (MOR) or converging (pacific ring of fire), and most volcanoes are found underwater. Besides plate boundaries, volcanoes can also be found on hotspots, that arise from upwelling diapirs with magma from the core-mantle boundary.
Name the direct and indirect hazards posed by volcanic eruptions.
direct: air fall, pyroclastic flow, CO2 lakes, lava flow
indirect: lahars, tsunamis, earthquakes, landslides
Why do earthquakes occur? What is the hypocentre, what is the epicentre?
Earthquakes are the result of the movement of the upper or lower surface of the Earth due to pressure along the fault line. Due to the rough fracture surface of the plates, a lot of pressure can build up and is released in a strong, sudden seismic wave.
The hypocentre is the place of first movement and the centre of energy depletion.
The epicentre is the point on the surface located vertically above the hypocentre.
What is the definition of magnitude on the Richter scale?
The maximum amplitude of the first seismic wave 100km from the epicentre.
Explain the terms primary, secondary and Rayleigh waves.
primary: compression/dilutions space wave, high speed
secondary: transverse shear-space wave, half speed of p-wave
rayleigh/love wave: interference wave
what is the Mecali scale?
scale (of 1 to 12) of the intensity of an earthquake
What is the reason for the dark colour of the areas called mare on the surface of the moon?
Dark silicates socalled basalt are the reason for the black colour of mare
which rock types are the bright areas on the moon and how did they form?
There are 2 different white rock materials that can be found on the moon. 1. Plagioclase. Almost 100 percent of the moon’s crust contains this mineral, which belongs to the feldspar. Plagioclase on the moon is a component of the anorthosite rock. The plagioclase, which has now been extensively detected, is believed to have crystallized when the magma seas cooled. The entire surface of the moon is covered with a fine-grained, powdery material, in which rocks of different sizes are scattered.
This mixture is called the regolith: it is the end product of millions of meteorite impacts, through which deeper material was thrown out and surface rock was broken up into smaller and smaller parts. It is about 20 m high in the highlands
How many planets are there in our solar system? What is the difference between gas planets and terrestrial planets?
There are 8 planets, 66 moons and 1 star (sun) in our solar system.
Mars, Earth, Venus and Mercury are so called terrestrial planets – they consist of silicate rocks. Jupiter, Uranus, Saturn and Neptune are gas planets – they consist of condensed ice particles.
What keeps the planets on the same plane?
Gravitation
the distance between planets always increases by?
50 percent
How old is the oldest in Austria, where is it found and what is is`s name?
1,38 Billion years, found: Waldviertel, Name: Dobragneis
Name 4 regional capitals in Austria, which were built in the area of the last Pleistocene (Alpine Glaciation)?
Bregenz, Innsbruck, Salzburg, Klagenfurt
When was the peak of the last Pleistocene glaciation in Austria?
Around 26.000-20.000 years called Würm
what was the name of the bay in the flysch zone of the vienna forest?
Flyschzone or Rhenodanubian Flysch is a narrow rock unit that extends to the north of the Eastern Alps and the Carpathians. Is part of the transition area of the Alps to the northern Alpine foothills. It mainly consists of clay and sandstone, which is why it was formerly called the sandstone zone.
Why is ocean important for people?
The ocean is capable of producing Oxygen
How could animals develop on land?
Which Tool is for measuring ground vibration?
Seismograph
Name and describe the two types of meteorites.
Ferreous meteorites: out of nickel-iron that are totally different from rocks on surface of the Earth
Stone meteorites: more similar to earths crust and mantle
ice age happens because of?
accumulating snow due to lower sun radiation. The accumulated snow bounces radiation so even more snow accumulated.
Which main part of the interior of the earth is liquid?
Outer core (waves can’t pass through this part)
Which part of the core consists mainly of minerals?
both (are made of minerals)
Name the main mineral group of the earth crust?
Quartz and feldspar (granite), Silicates (basalt)
Name two important observations which are connected with the liquid part of the earth interior?
Magnetic field, Seismic waves
Material of earth?
- Granite,
- basalt,
- ultramafic rocks
Name the five structures silicates can have.
- isolated tetrahedra,
- chain of tetrahedra,
- double chain of tetrahedra,
- sheet of tetrahedra,
- complex three-dimensional network.
biggest CO2 storage of the planet?
Limestone
What and where is the Lithosphere?
olid skin on the surface, its movement on the Asthenosphere is caused by convection.
If the whole earth history would be reduced to one calender year, during which month of this calender year mammals evolved?
December
