EESA06H3 Lecture 5: Intro to Planet Earth Lecture 5
Document Summary
Uniformitarianism: the present is the key to the past (actualism) The limit of uniformitarianism is that we can only look at what is happening today examples are meteoroids and super volcanoes. Most mid ocean ridges under water very expensive to go under water and study them. Continental breakup: the formation of passive plate margins- plates move around slide past, collide when they collide call them active plate margin. When continents break up we create passive margins they are on trailing edge of the plate. Abyse planes l anything that is deep. Magnetic stripes ensure that this process has occurred alternating stripes tells us the age, and looking at the width shows the rate of spreading. There is a finite age to the ocean floors and variations in the rate of spreading. The zone is wider more ocean is produced, pacific is very fast spreading. Mid ocean ridges can be classified in slow, intermediate and fast much faster in eastern specific.