G101/201 OBJECTIVES                                          

Chapter 4 ‑ Igneous Rocks and intrusive activity

 

1.   Differentiate between:

               a.  intrusive vs extrusive                                b.  plutonic vs volcanic

 

2.  Describe the factors that contribute to crystal size within an igneous rock

 

3.   Differentiate between an extrusive and an intrusive igneous rock on the basis of the following   environmental parameters and explain how they generally affect the texture and crystal development of      the rocks

               a.  influence of water and water retention     b.  time of crystallization/cooling time

                                                                                               

4.   Understand the following terms:

               a.  vesicle                                                      b.  viscosity

              

5.  Describe the classification of each composition of igneous rocks on the basis of silica content and proportions of iron, magnesium, and calcium

               a.  ultramafic                                                c.  intermediate                       

               b.  mafic                                                       d.  silicic (felsic

 

6.   Be able to give an examples for each of the rock classifications in objective 5                

 

7.  What are the factors that control the viscosity of magma/lava.  Be able to explain how temperature, silica and water content can change viscosity.

 

8.  Know the following “pairs” of rocks with regards to their composition and be able to identify which are       intrusive and which are extrusive.

                                                Intrusive                      Extrusive

                                                Granite                         Rhyolite

                                                Diorite                         Andesite

                                                Gabbro                        Basalt

                                                Peridotite                     Komatiite        

 

9.   Understand the sequence of crystallization in igneous rocks as described by the Bowen's Reaction Series and differentiate between the continuous and discontinuous series. 

 

10. Be able to use Bowen’s reaction series to predict the composition of a magma from partial melting

                                                                                                                                                           

11.  Name three factors that contribute to the melting of rock.

 

12. Describe how magmatic differentiation can change the composition of magma through time via the        following:

               a.  crystal settling (gravity separation)           d.  filter pressing

               b.  partial melt                                               e.  magma mixing

               c.  assimilation

 

                                                                                                                                    (OVER)

13.          Describe the geologic environment that forms each type of igneous rock.

               a.  peridotite family (ultramafic)                   c.  andesite family (intermediate)

               b.  basalt family (mafic)                               d. granite family (felsic)

              

14. Define the term plutonic and describe the following plutonic structures:

               a.  dikes                                                        d.  laccoliths/lopoliths (201 students)

               b.  sills                                                           e.  batholiths

               c.  xenoliths                                                   f.  stocks

 

15. Describe the composition and emplacement of batholiths.