Section #: 21.2 Relative-Age Dating of Rocks

Practice Test
      
  1.Which layering shown in the figure demonstrates disconformity?



 
  a.   A  
  b.   B  
  c.   C  
  d.   none of the above  
  Hint    
      
  2.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    
      
  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.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    
      
  5.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    
      
  6.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    
      
  7.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    
      
  8.Which feature shown in the figure is the oldest?



 
  a.   H  
  b.   L  
  c.   P  
  d.   Q  
  Hint    
      
  9.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    

 
   
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