EARTH238 Lecture Notes - Lecture 24: American Cordillera, Triple Junction, Transpression
Lecture 24
*Skipped lecture 23 14/03/2016
- Fault Systems
o Normal fault
▪ Extension
▪ Associated w/ divergent plate boundaries (MoR)
▪ Listric fault **
▪ Think skinned
• Only the overlying layers of sedimentary rock are deformed and the
basement is left undeformed
▪ Thick skinned
• Both the overlying layers and the basement are deformed
▪ Antithetic
• Major fault dips one way while the smaller faults dip the other way
▪ East African Rift
• Triple junction
• As the plume pushes up 3 rifts spread the continent apart
• The East African Rift stopped rifting whereas the other two continued
rifting creating the Gulf of Aden and the Gulf of Suez
▪ North American Cordillera
o Reverse fault
▪ Regional shortening
▪ Thrust duplex
o Strike-slip fault
▪ If the faults move at oblique angles to each other there is a transpressive
component and a compressive component
▪
find more resources at oneclass.com
find more resources at oneclass.com