Earth Sciences 2240F/G Lecture Notes - Lecture 3: Asthenosphere, Convection, Seismic Wave
15 Oct 2016
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Alfred wegener was the rst to start the formulation of a the continental drift theory, he published his ideas in 1912. 2. 5cm/year the pattern discovered by those magnetometers used in wwii were directly a re ection of earth"s magnetic eld. !1 following these ips" the magnetic eld may remain stable for many million of years- but in what we call a reverse polarity as opposed to the polarity of today, we choose to call normal. Hugo benioff worked on the development and application of instruments (seismographs) to accurately measure earthquake locations; his co-worker (the guy who eventually perfected the instrument) was charles richter. Theory is complete we established you cannot push a think crust ( from a distant spreading centre), and you cant drag a thin crust ( on the back of a convection current). Nd that slab pull"- the effect of gravity- accounts for about 90% of the force.
