Section #: 21.2 Relative-Age Dating of Rocks

Practice Test
      
  1.The principle of _________ states that an intrusion or fault is younger than the rocks it cuts across.  
  a.   uniformitarianism  
  b.   superposition  
  c.   cross-cutting relationships  
  d.   original horizontality  
  Hint    
      
  2.What is an erosional contact between sedimentary and nonsedimentary rocks called?  
  a.   a nonconformity  
  b.   a lava flow  
  c.   a fault  
  d.   a disconformity  
  Hint    
      
  3.If a horizontal Devonian shale directly overlies a horizontal Ordovician limestone, what is the surface between the strata called?  
  a.   an angular unconformity  
  b.   a disconformity  
  c.   a nonconformity  
  d.   an erosional surface  
  Hint    
      
  4.Which layering shown in the figure demonstrates disconformity?



 
  a.   A  
  b.   B  
  c.   C  
  d.   none of the above  
  Hint    
      
  5.Which feature shown in the figure is the oldest?



 
  a.   H  
  b.   L  
  c.   P  
  d.   Q  
  Hint    
      
  6.What geologic principle states that in an undisturbed rock sequence, the oldest rocks are on the bottom and the youngest are on the top?  
  a.   uniformitarianism  
  b.   cross-cutting relationships  
  c.   superposition  
  d.   original horizontality  
  Hint    
      
  7.What does a disconformity in a sedimentary rock sequence represent?  
  a.   a gap in the rock record  
  b.   a flood event  
  c.   a volcanic eruption  
  d.   duplicated strata in the rock record  
  Hint    
      
  8.What principle of geology states that sedimentary rocks are deposited horizontally or nearly horizontally?  
  a.   uniformitarianism  
  b.   cross-cutting relationships  
  c.   superposition  
  d.   original horizontality  
  Hint    
      
  9.The __________ states that the processes that have been occurring today have been occurring since Earth formed.  
  a.   principle of uniformitarianism  
  b.   principle of original horizontality  
  c.   principle of cross-cutting relationships  
  d.   principle of superposition  
  Hint    

 
   
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