Earth Flashcards
What are the four main components in the earth systems
atmosphere,hydrosphere,geosphere and biosphere
What is Atmosphere?
Air zone covering the Earth’s surface.
What is Biosphere?
Life zone consists of a variety of life such as humans, animals, plants and microorganisms
What is Hydrosphere?
Water zone that includes rivers, lakes, seas and also water trapped as ice, underground water and water vapour in the atmosphere.
What is geosphere
Rock and soil zone on the Earth’s surface.
Earth’s atmosphere consists of five layers.Name all of them.
Troposphere,Stratosphere,Mesosphere,Thermosphere and Exosphere
What is Troposphere
The layer where living organism breathes, wind blows and where clouds, rain and snow form.
What is Stratosphere
The ozone layer that contains ozone gas which absorb harmful ultraviolet rays from sunlight is found here.
The ozone layer depletes when chlorofluorocarbons (CFCs) released from pesticides, refrigerators and air-conditioners break down ozone molecules in the ozone layer.
What is Mesosophere
Burning and destruction of meteorites occur in this layer.
What is Thermosphere
Also known as the ionosphere because it contains ions that can reflect radio waves.
Aurora, a stream of colourful lights resulting from reactions of charged particles with Earth’s magnetic field and atmospheric gases occurs here
What is Exosphere
Contains light gases such as helium and hydrogen.
Air becomes thinner towards space.
Communication satellites orbiting Earth in this layer allow phone calls and television broadcasts.
what is a crust
the outmost layer of the earth and is solid
The top layer is the continent that is composd of granite,while beneath the granite is a layer of hard rock known as basalt
consists of igneous rocks
what is mantle
The upper mantle beneath the lithosphere consists of semi-molten rock due to high temperature,that is 1400C (asthenosphere)
Why is the mantle unstable?
due to convection current that causes the movement of the mantle
What is core
consists of two layers which are outer core and inner core is believed to be a solid form.
What is Igneous rock?
Formed from the process of cooling and freezing of magma or lava that flows out of the mantle.
Contains various minerals.
What is Sedimentary rock?
Formed by compression of deposited materials carried by the rivers, glaciers and wind
Consists of many layers which are sometimes hollow and contain fossils.
What is Metamorphic rocks
Formed when igneous rocks or sedimentary rocks are exposed to very high pressure and temperature.
Usually harder than the original rocks that formed them
What is Exogenic process?
Occurs above the Earth’s surface
Examples: Weathering, erosion , mass and land depletion, transport and sedimentation
What is weathering
Process of rock fragmentation and decomposition or decay due to changes in temperature, rainwater, frosting and microorganisms.
What is erosion
Process of eroding of the Earth’s surface moving agents (water, wind and waves)
What is Mass depletion and land depletion
Involves soil movement from the top of a slope to below as a result of gravititonal force
transport and sedimentation
Weathered and corroded materials are moved by agents.
The materials will be sedimented when the velocity of the agents decreases.
What is endogenic process?
Caused by forces from within the Earth
Forms and changes the Earth’s surface
Examples: Mantle convection process, magma activity and Earth’s crust movement (Plate Tectonics)
What is mantle convection
High temperature in the mantle and the core of Earth produces convection currents in the atmosphere layer.
What is magma activity
Volcano is a vent on the Earth’s crust that allows molten and hot magma to flow out through it in a strong eruption.
What is plate tectonics
The Earth’s crust is divided into several pieces of plates.
These plates constantly move resulting in collision and divergence which produce various landforms in Earth and continental drifts.
