eosc 116 mod e
MODULE E – Planetary Engineering: Mesozoic Tectonics
Lesson 17 – Plate Tectonics 101
Introduction
- Plate Tectonics = “Grand Unifying Theory” explaining relationships between processes within Earth
From Theory of Continental Drift
- Alfred Wegener in 1915
The Theory of Plate Tectonics
1) Earth’s surface consists of many lithospheric plates including crust (continental or oceanic) and immediately underlying mantle, cold and rigid
2) These plates are presently moving around on Earth’s surface and interacting with one another
-some lithospheric plates consist of both continental and oceanic floor ex) N.American plate = N.American continent and western half of Atlantic Ocean
Indian-Australian plate = continental rocks of India, Australia and oceanic floor
Plate Motion
- plate motions random rates and directions
- rates of 2-18 cm/yr quite slow, but with perspective of geological time in terms of million years, rates of 100’s of km/million years means entire oceans can be destroyed in tens millions years
Significance of plate tectonics
1) Almost all earthquakes, most volcanoes, occur where lithospheric plates are interacting
2) Main mineral and hydrocarbon resources occur in specific tectonic settings
3) Plate tectonic processes happening at depth responsible for occurrences at Earth’s surface: size and shape of oceans, nature and distribution of landforms, general climatic conditions of each of
Earth’s regions
Plate Boundaries
- map of epicenter of significant earthquake, M > 3.5
- active boundaries marked by zones of earthquakes and volcanoes
- earthquakes closely associated with active plate boundaries
Land forms associated with plate boundaries
-mountain belts occur along many plate boundaries
- N. America: main mountain belts stretch from Alaska to northwest N. America all the way to south along western edge of N. and S. America
Oceanic forms associated with plate boundaries
- topography of ocean floors is very irregular, including
Lesson 17 – Plate Tectonics 101
Introduction
- Plate Tectonics = “Grand Unifying Theory” explaining relationships between processes within Earth
From Theory of Continental Drift
- Alfred Wegener in 1915
The Theory of Plate Tectonics
1) Earth’s surface consists of many lithospheric plates including crust (continental or oceanic) and immediately underlying mantle, cold and rigid
2) These plates are presently moving around on Earth’s surface and interacting with one another
-some lithospheric plates consist of both continental and oceanic floor ex) N.American plate = N.American continent and western half of Atlantic Ocean
Indian-Australian plate = continental rocks of India, Australia and oceanic floor
Plate Motion
- plate motions random rates and directions
- rates of 2-18 cm/yr quite slow, but with perspective of geological time in terms of million years, rates of 100’s of km/million years means entire oceans can be destroyed in tens millions years
Significance of plate tectonics
1) Almost all earthquakes, most volcanoes, occur where lithospheric plates are interacting
2) Main mineral and hydrocarbon resources occur in specific tectonic settings
3) Plate tectonic processes happening at depth responsible for occurrences at Earth’s surface: size and shape of oceans, nature and distribution of landforms, general climatic conditions of each of
Earth’s regions
Plate Boundaries
- map of epicenter of significant earthquake, M > 3.5
- active boundaries marked by zones of earthquakes and volcanoes
- earthquakes closely associated with active plate boundaries
Land forms associated with plate boundaries
-mountain belts occur along many plate boundaries
- N. America: main mountain belts stretch from Alaska to northwest N. America all the way to south along western edge of N. and S. America
Oceanic forms associated with plate boundaries
- topography of ocean floors is very irregular, including