4th Quater

• convergent boundary is present when two plats move toward each other
• transform boundary exists when there is no destruction or formation of new lithosphere
• trench and volcano are considered as surface manifestations of convergent boundaries
• continental - oceanic convergence is the formation of oceanic trenches which are often characterized by long and deep rift mainly caused by subducting oceanic lithosphere in the mantle
• in divergent plate boundary and continental-continental convergence partial melting and production of magma takes place
• convergent plate boundary enables shallow earthquakes to occur
• remember!

  
• alfred wegener proposed the theory of continental drift
• if the plate tectonic movements permanently stop

  1. the formation of new volcanic islands in Hawaii will stop
  2. Erosion will dominate over the formation of new landforms
• Mesosaurus is an aquatic fish-catching reptile found in both South America and Africa
• the oceanuc crust is youngest adjacent to the mid-oceanic ridges is one of the results from the data gathered during deep ocean drilling
• the oceanic crust is youngest adjacent to the mid-oceanic ridges is one of the results from the data gathered during deep ocean drilling
• convection cells is the driving mechanism of plate movement
• continental drift claims that the continents drifted apart from a super continent while plate tectonics teaches that the lithosphere is divided into several plates moving over Earth
• Wegeners continental drift theory was criticized because he was not able to explain how the continents move and he claimed that larger and sturdier continents broke through the thinner oceanic crust
• plate tectonics is called the unifying theory og geology because this can explain large-scale phenomena such as earthquakes, volcanoes, and ocen floor formation
• robert dietz and harry hess proposed the seafloor spreading hypothesis
• the longest mountain range in the world is the mid-oceanic ridge
• seafloor spreading do not have the same age all throughout. it gets older as it moves aways from the oceanic ridge
• Increasing age of oceanic crust as it moves away from the ridge shows that the seafloor is spreading
• shear stress is a type of stress that is characterized by two forces acting in parallel but opposite directions which causes the rocks to simply past slide each other
• faulting is a type of deformation that occurs if the rocks subjected to stress is brittle
• if the ages of rock is unknown, an upward-arched form is called antiform
• the behavior of rock under stress depends on the nature of material, temperature, pressure, and time
• reverse fault is a type of fault that is a product of compressive stress
• at greater depth, there is a higher temperature and pressure condition making the original rock behave as ductile and plastic
• Graben is formed when the block between two normal faults are down-dropped
• the factors that you should change for the rock to undergo plastic deformation are:

  • increase the amount of time during the application of stress
  • increase the temperature and pressure
• the overlying side if the fault is called the hanging wall and is named as such because miners noticed that it is usually the side that hung over their heads.
• the side beneath the fault and most of the time where the miners walked is called footwall
• Robert Dietz and Harry Hess proposed the seafloor spreading
• the longest mountain range in the world is the mid-ocean ridge
• the seafloor gets older as it moves away from the oceanic ridge
• the seafloor is relatively thin and basaltic in composition
• the seafloor is composed of oceanic crust that is denser than the continental crust
• sediments are accumulated in the ocean floor
• new oceanic crust is being firmed in the mid-oceanic ridge
• transform faults divide the extensive mid-oceanic ridge into several short segments that are slightly offset from each other
• a large chunk of the oceanic crust with old age can be found in the Pacific ocean
• the slightly elevated area formed by the submarine mountain was caused by the relatively lower density of the fresh hot lava coming through the crust