Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Plate Tectonics Lab 1
Document related concepts
Transcript
Figure 3.12 Igneous Rocks (Lab ) The Rock Cycle Sedimentary Rocks Metamorphic Rocks (Lab ) (Lab ) Areas of regional metamorphism Compressive Stress Compressive Stress Products of Regional Metamorphism Products of Contact Metamorphism Foliated texture forms during compression Non-foliated texture forms during static pressure Texture Minerals Other Diagnostic Metamorphic Features Rock Name Protolith Non-foliated calcite, dolomite cleavage faces of calcite usually visible Marble Limestone quartz quartz grains are intergrown Quartzite Quartz Sandstone clay looks like shale but breaks into layers Slate Shale muscovite, biotite very fine-grained, but has a sheen like satin Phyllite Shale muscovite, biotite, may have garnet minerals are large enough to see easily, muscovite and biotite grains are parallel to each other Schist Shale feldspar, biotite, muscovite, quartz, garnet has layers of different minerals Gneiss Any protolith amphibole layered black amphibole grains Amphibolite Basalt or Andesite Foliated Texture Minerals Other Diagnostic Metamorphic Features Rock Name Protolith Non-foliated calcite, dolomite cleavage faces of calcite usually visible Marble Limestone quartz quartz grains are intergrown Quartzite Quartz Sandstone clay looks like shale but breaks into layers Slate Shale muscovite, biotite very fine-grained, but has a sheen like satin Phyllite Shale muscovite, biotite, may have garnet minerals are large enough to see easily, muscovite and biotite grains are parallel to each other Schist Shale feldspar, biotite, muscovite, quartz, garnet has layers of different minerals Gneiss Any protolith amphibole layered black amphibole grains Amphibolite Basalt or Andesite Foliated Identification of Metamorphic Rocks 12 samples 7 are metamorphic 5 are igneous or sedimentary Protoliths and Geologic History For 2 of the metamorphic rocks: Match the metamorphic rock to its protolith (both from Part One) Write a short geologic history of the sample Formation of the protolith 2. Burial to the depth where metamorphism takes place 3. Metamorphism 4. Uplift and erosion to bring the metamorphic rocks to the surface 1. Metamorphic Sample Number 2 Metamorphic Rock Name Gneiss Protolith Sample Number Protolith Rock Name 7 Granite Geologic History 1. Granitic magma intruded in the Earth's crust and crystallized to form granite. 2. Granite was forced deeper in the crust by plate tectonics. 3. Granite was metamorphosed to form gneiss. 4. The rocks above the gneiss were eroded away to expose the gneiss at the surface. Interpretation of Metamorphic Rocks Contact Metamorphism Match the protolith to the metamorphic rock Determine the thermal gradient (direction of increasing temperature) during contact metamorphism Regional Metamorphism Using five metamorphic rocks (from Part One), determine the direction of the thermal gradient during regional metamorphism for this example Also, determine the direction of compressive stress during metamorphism
