ERS111H5S Lecture Notes - Lecture 5: Mid-Ocean Ridge, Continental Margin, Pangaea
41 views2 pages

ERS111 WEEK 4 THURSDAY AND WEEK 5
• Diagram***
• Detect changes in magnetic field
• Striped magnetic fields of different magnitudes
• Chuck weight off their boat and measure how much rope goes down into the ocean
• Wasn’t until the invention of sonar than we knew the depth of the ocean
• Mid ocean ridge: mountain plane in the middle of the ocean
• Mapping locations of earthquakes
• Earthquakes happen when rocks are moving due to energy
•
• pangaea
• Evidence of glaciation that was timed at around the same found on all continents
• Everything was once clustered at the south pole
• Size of sand grains, composition of sediments
• We can say that one environment in the past is the same as it is today
• Before dinosaurs
• These animals/plants couldn’t have travelled over oceans as the world is today
• Same age and graphical position
• Continents move very slowly over time
• Diagram**
• Magma might be forcing continents apart
•
• Normal or reversed polarity
• Also look at magnetic field in rocks
• Diagram***
• Diagram**
• Map of tectonic plates of earth
• 2 types of continental margin
• Active: where we have plate boundaries
• Passive: where there is no active plate boundary, no volcanos
• Diagram***
• Lithosphere at plate boundary is thin
• Asthenosphere is pushing upwards