Plate Tectonics and The Rock Cycle
Three types of plate boundaries Divergent plate boundaries Plates move apart from one another Convergent plate boundaries Internal forces push two plates together Transform faults Plates slide and grind past one another along a fault line
Divergent plate boundaries Mid-Atlantic Ridge
Convergent plate boundaries
When a tectonic plate sinks, it sinks down into the mantle and becomes very hot. So hot, in fact, that the rock melts. This molten rock will gradually make its way up to the surface of the earth through a series of cracks. When it reaches the surface of the earth, we refer to it as lava. As layer upon layer of lava builds up, a volcano is formed.
Transform fault
Convergent and Transform
San Andreas Fault
How much stronger is an earthquake with a magnitude of 9 How much stronger is an earthquake with a magnitude of 9.0 versus an earthquake with a magnitude of 4.0? 9.0 – 4.0 = 5.0 105 = 100000 times stronger
How tsunamis occur
Three types of rock Igneous Sedimentary Metamorphic Granite, lava rock Sandstone, shale, dolomite, limestone, lignite, bituminous coal Metamorphic Anthracite, shale, marble
Igneous rock Forms below earth’s surface, when molten rock comes up from the upper mantle, cools, and hardens
Sedimentary rock Forms from sediments deposited in layers which accumulate over time – the weight and pressure “cements” these layers together
Cementation – minerals are precipitated in the pores of sediments, forming cements that bind sediments and rock Lithification – the process that converts sediments into solid rock by compaction and cementation
Metamorphic rock Forms when preexisting rock is subjected to high temperatures, high pressures, chemically active fluids, or a combination of these agents
Rock cycle Interaction of physical and chemical processes Recycles the earth three types of rocks Slowest of earth’s cyclic processes Concentrates the planet’s nonrenewable minerals Without it we would not exist
Closure Why is it important to understand the three major processes (tectonic cycle, rock cycle, and soil formation) of the geologic cycle?
Japan Tsunami 2011