National Statistic and Geographic Area

The earth is surrounded by a magnetic field . Magnetic lines of force originate from north and south magnetic poles, which are about 11 .5 degrees away from the geographic North and South Poles. The magnetic field is strongest at the magnetic poles. The positions of the magnetic poles have changed over time and appear to be rotating around the geographic poles on
an axis tilted from the geographic axis by 11 .5 degrees . The magnetic field traps high-energy particles created by the sun’s ultraviolet radiation, thus protecting our environment on Earth.

The magnetic field is thought to be generated by the liquid outer core. If this liquid material is metallic, as geophysical studies suggest, its flow as a result of heat convection would create an electric current Electric currents induce magnetic fields.
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The process of weathering alters rocks at the earth’s surface and breaks them down over time into fine-grained particles of sediment and soil . Weathering is the result of the interactions of air, water, and temperature on exposed rock surfaces and prepares the rock for erosion.

Erosion is the movement of the particles by ice, wind, or water. The particles are then transported by that agent until they are deposited to form sedimentary deposits, which can be later eroded again or transformed into sedimentary rocks. The weathering of the sediment grains continues during erosion and transportation. Weathering is generally a long, slow process that is continuously active at the earth’s surface.
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