2.  Take out your HW  On your table using the chalk:  Draw the diagram that shows crust, mantle, lithosphere, and asthenosphere  Draw a T chart that compares the thickness and composition of Oceanic and Continental Crust  How would you define a plate?

3.  Archimedes Principle Archimedes Principle  What is density?  How did Archimedes measure the VOLUME of the King’s crown?  How might archimedes principle be useful to geologist in determining the density of the rocks which make up the earth’s crust?

4.  BASALT SAMPLES:  Antarctica  Australia  Asia  GRANITE SAMPLES:  Africa  S. America  Europe

5. 1. Measure the mass of a rock sample to.01 g: __________g 2. Tie string to rock sample. Carefully lower rock by string into displacement can. Record volume of displaced water to 0.1 mL: ________cm 3  This is the volume of the rock sample; remember: (basalt) (granite) 1 mL = 1 cm 3  Calculate density of the rock using formula: D = M/V ▪ (Density = Mass/Volume).  Use the values you recorded in steps 1 and 4  Be sure to label with the density unit: g/cm 3  Show your work on the tables

6.  Which crust is more dense?  What do you expect will happen if continental crust comes into contact with oceanic crust?  What if continental crust comes into contact with continental crust?  Google Phet simulations  Search for plate boundaries in the search section  Play with simulation for 5 minutes  Make at least three “solid” observations (no pun intended)