Name_____________________ Igneous Rock ID Lab Using your “Dichotomous Key for Igneous Rocks”, identify the numbered rock samples. On your data table, include the rock name, type of igneous rock and identifying characteristics. Rock Sample Number 1 Rock Name Intrusive (Cooled Slowly) Extrusive (Cooled Quickly) Formed from Magma or Lava 2 3 4 5 6 7 Name_____________________ Igneous Rock ID Lab Using your “Dichotomous Key for Igneous Rocks”, identify the numbered rock samples. On your data table, include the rock name, type of igneous rock and identifying characteristics. Rock Sample Number 1 2 3 4 5 6 7 Rock Name Intrusive (Cooled Slowly) Extrusive (Cooled Quickly) Formed from Magma or Lava Analysis: 1. Make a general statement about how igneous rocks are formed. Use evidence from the investigation to help you write your statement. ____________________________________________________________________________________________________ ____________________________________________________________________________________________________ ____________________________________________________________________________________________________ 2. Explain how the cooling rate of molten material affects the formation and the grain size of igneous rocks. Provide examples from the investigation to support your response. ____________________________________________________________________________________________________ ____________________________________________________________________________________________________ ____________________________________________________________________________________________________ 3. Which igneous rock was the easiest for you to identify? Why? ____________________________________________________________________________________________________ ____________________________________________________________________________________________________ 4. Which igneous rock was the most difficult for you to identify? Why? ____________________________________________________________________________________________________ ____________________________________________________________________________________________________ Analysis: 1. Make a general statement about how igneous rocks are formed. Use evidence from the investigation to help you write your statement. ____________________________________________________________________________________________________ ____________________________________________________________________________________________________ ____________________________________________________________________________________________________ 2. Explain how the cooling rate of molten material affects the formation and the grain size of igneous rocks. Provide examples from the investigation to support your response. ____________________________________________________________________________________________________ ____________________________________________________________________________________________________ ____________________________________________________________________________________________________ 3. Which igneous rock was the easiest for you to identify? Why? ____________________________________________________________________________________________________ ____________________________________________________________________________________________________ 4. Which igneous rock was the most difficult for you to identify? Why? ____________________________________________________________________________________________________ ____________________________________________________________________________________________________