Geography 2 Flashcards
_____ measures the magnitude of an earthquake.
Richter Scale
_____ measures the damage cause by an earthquake.
Mercalli Intensity Scale
____ is the place of origin of an earthquake.
Focus
_____ is the area perpendicular to the focus.
Epicentre
_____ is the study of earthquakes.
Seismology
The _____ waves of an earthquake can move through solid rock and fluids, like water or the liquid layers of the earth.
Primary or ‘P’ waves
Which type of wave causes the most structural damage on earth?
Surface waves or ‘L’ waves
Indian plate clashes with ____ plate, which is also responsible for the Himalayas ranges rising by 1 cm each year.
Eurasian plate
The Indian plate is moving from South to North at ____ speeds.
5 cm / year
Which is the second most important earthquake zone in India?
Parallel to Punjab & Rann of Kutch
Which are the earthquake prone states in India?
Arunachal Pradesh, Mizoram, Assam, Nagaland, Jammu & Kashmir, Manipur, Adaman & Nicobar Islands, Tripura, north Bihar
Which are the three traditional zones of earthquakes?
- Circum Pacific Belt
- Mid Atlantic Belt
- Mid Continental Belt
What are shadow zones?
Areas where earthquakes rarely occur
_____ explosions lead to the formation of lava plateaus.
Fissure / quiet
- eg: Deccan plateau
Examples of active volcanoes
Etna [Italy], Stromboli [Italy], Mayon [Philippines]
Examples of dormant volcanoes
Fujiyama [Japan], Krakatoa [Indonesia]
What is the name of the world’s highest active volcano?
Hawaii’s Mauna Loa
What is the shortest volcano in the world?
Cuexcomate, Mexico
- has been used to store meals and dispose of dead bodies
Highest volcano on earth
Ojos del Salado, Chile [6873 m]
_____ rocks are also called primary rocks.
Igneous
- formed by cooling of magma
- hard and granular; less affected by chemical erosion
- eg: Granite, Sills, Basalt
Examples of sedimentary rocks
Mechanically formed: Sandstone
Chemically formed: Gypsum
Organically formed: Coal, limestone
_____ rocks change in form or composition without disintegration.
Metamorphic
What are agents of metamorphism?
Heat, solution, compression
- Metamorphism occurs because some minerals are stable only under certain conditions of pressure and temperature. When pressure and temperature change, chemical reactions occur to cause the minerals in the rock to change to become stable at the new pressure and temperature conditions.
Give the metamorphic rock forms of the following rocks.
- Limestone
- Sandstone
- Coal
- Shale
- Clay
Limestone --> Marble Sandstone --> Quartzite Coal --> Diamond Shale --> Slate Clay --> Slate
Examples of fold mountains
Young (post continental drift): Himalayan, Alps, Andes, Rockies
Old (pre-drift era): Appalachians, Aravalli, Pennines
- Himalayas is the youngest mountain range.
Example of block mountains
Vindhya and Satpura ranges, India
Black forest, Germany
Volcanic mountains are also called _____.
Mountains of Accumulation
eg: Mt. Fuji [Japan], Cotopaxi [Andes], Etna [Italy], Mayon [Philippines]
Examples of residual / dissected mountains in India
Nilgiris, Girnar, Deccan Plateau
Highest plateau in the world
Tibetan plateau
- tectonic plateau
When plateaus are enclosed by fold mountains, they are called _____.
Intermont plateau
Examples of dissected plateau
Scottish Highlands
- a plateau that has been intensely eroded so that the relief becomes sharp
- eroded region tends to appears mountainous or as hilly slopes and valleys
97% of the Earth’s atmosphere comes within the height of _____ from the Earth’s surface.
29 km
The atmosphere extends _____ miles from sea level.
600
Composition of gases in the atmosphere.
Nitrogen: 78%
Oxygen: 21%
Argon, CO2, Neon: 1%
What is the normal lapse rate of temperaute?
Drop of 1 degree Celsius every 165 m
_______ separates the troposphere and stratosphere.
Tropopause
All weather conditions occur in this layer of atmosphere.
Troposphere
What is temperature inversion in the atmosphere.
In the stratosphere, temperature increases with the increase in height.
The ozonosphere lies in the ______.
Stratosphere
_____ layer in the atmosphere is considered ideal for flights and jets.
Stratosphere
- it’s free of dust particles and atmospheric turbulences
_____ is the coldest layer of the atmosphere.
Mesosphere
Mesopause separates _____ from _____.
Mesosphere, Ionosphere
____ layer of atmosphere makes radio communication possible.
Ionosphere
- contains electrically charged ions that reflect radio waves back to Earth
____ acts as a protective layer from meteorites.
Ionosphere
____ is the outermost layer of atmosphere.
Exosphere
______ and _____ layers display temperature inversion.
Stratosphere & Thermosphere
The outer part of the exosphere is called _____.
Magnetosphere
Solar radiation intercepted by Earth is called _____.
Insolation
- measured with pyranometers
What is Albedo?
Portion of radiation energy of the sun reflected from the earth’s surface
The mechanism of maintaining the same temperature throughout by the atmosphere is called ______.
Heat Budget / Heat Balance
What is atmospheric pressure?
The pressure exerted by the atmosphere on the Earth’s surface because of it’s weight.
- Factors that influence AP is altitude, rotation of earth and temperature
The ______ is also called the belt of calm or doldrums.
Equatorial Low Pressure Belt
- located on either side of geographical equator [between 5°N and 5°S]
- zone of convergence of NE and SE trade winds
- thermally induced
- characterised by light feeble winds
The ____ is also called the Horse Latitude.
Sub-Tropical High Pressure Belt
- between 30°-35° on either side
- dynamically induced by rotation
Sub-Polar Low pressure belt
Between 60°-65° on either side
- dynamically induced
- more developed in South Hem, due to larger presence of oceans that NH
Polar High Pressure Belt
High pressure throughout the year due to consistent low temperatures
The slope of air movements from higher to lower pressure is called pressure gradient. Another name for it is _____.
Barometric slope
______ caused by the rotation of the Earth deviates the expected direction of wind movement.
Coriolis Effect
- winds deflected to right in the North & left in the South
- no effect on the equator; keeps rising towards the poles
_____ law predicts the deflection of a particle (water, air, ice, or the like) in motion of the Coriolis effect.
Ferrel’s
The Westerlies are called ____ in 40-50°, _____ at 50° and ______ at 60°.
Roaring forties, furious fifties, screaming sixties
The westerlies blow from _____ to _____.
Sub-tropical high pressure belt to Sub-polar low pressure belt
Polar winds blow from ______ to _____.
Polar high pressure belts to Sub-polar low pressure belts
_____ winds reverse direction every 6 months.
Seasonal
Eg: Monsoon winds
_____ cyclones are not found between 0-8° as there is no Coriolis effect there.
Tropical cyclones
Which cyclones are smaller in size - tropical / temperate?
Tropical
______ are also known as a weatherless phenomena.
Anti-cyclones
- high pressure in their center and low pressure moving outward
- centre to outward moves clockwise in NH; anticlockwise in SH
How is humidity measured?
Hygrometer & sling psychrometer
How do you measure relative humidity?
(Absolute humidity / Humidity capacity) x 100
When is the temperature said to be at dew-point?
When air is completely saturated with 100% humidity
As per international standards, visibility of less that _____ is considered to be fog.
1 km
Visibility of 1-2km is considered _____.
Haze
_____ rainfall occurs due to ascent of air forced by a mountain barrier.
Orographic
The windward side of slopes have ____ clouds and leeward side has ____ clouds.
Cumulous, stratus
Types of clouds
- Cirrus: feather looking, high clouds
- Cumulus: heap looking, flat bases and rounded tops
- Stratus: layer type clouds
- Alto: high
- Nimbus: rain clouds
Names of high clouds
Cirrus, cirro-cumulus, cirro-stratus
Names of middle clouds
Alto-cumulus, alto-stratus
Names of low clouds
Strato-cumulus, nimbo-stratus [often gives continuous rain], stratus
Names of clouds with vertical extent
Cumulus, cumulo-nimbus [convectional precipitation clouds]
Famous grasslands of the world
Steppe [Eurasia] Prairie [USA] Pampas [Argentina] Downs [Australia] Cantebury [New Zealand] Pustaz [Hungary]
______ is a line on a map connecting points having equal incidence of a specified meteorological feature.
Isopleth
_____ provide the richest fishing grounds in the world. 20% of petrol and gas are also found here.
Continental Shelves
The boundary between a continental shelf and slope is called ____.
Andesite Line
_____ cover 76% of total oceanic area.
Abyssal / Deep Sea Plains
A ridge rising more than 1000m above the ocean floor is called a ______.
Seamount
- flat topped sea mounts are called Guyouts
- formed by volcanic activity
- largest number found in Pacific
Coral reefs are formed by the accumulation of skeletons of lime secreting organisms called ______.
Coral polyps
Coral Reefs
- mostly found in tropical oceans and seas; need high annual temperature
- not found in deeper parts of ocean due to lack of sunlight
_____ corals develop along the continental margins.
Fringing
- they could get detached from shore by the lagoon ‘Boat Channel’
- found in Rameshwaram
Largest coastal reefs
Barrier reefs
- Found in Nicobar and Lakshadweep
- Great Barrier Reefs in Australia are largest barrier reefs in the world
What is coral bleaching?
When corals are stressed (by temperature, light or nutrients) and release the algae living on them, making their colour turn white.
Average salinity in ______ hemisphere is greater than ______ hemisphere.
Southern, Northern
Most saline water body
Lake Assel [35%]
- Dead sea has 33.7 salinity
