GEOL 105 Study Guide First Mid-Term, Spring 2015 The first mid-term will be given in class on Wednesday Feb 18; it will cover the material presented in lectures from Jan 12 through Feb 13 and the reading assignments from Chapters 1-7 and 12 of the textbook. Note: this guide is not intended to be comprehensive. You should review the lecture notes, and do the assigned reading, as part of your preparation for the mid-term. The questions below are intended to give you an idea of the sort of things you should know. What are the main layers that make up our planet? What are they made of, and how thick are these layers? Can you explain the difference between the crust and the lithosphere? What is meant by isostasy? Can you explain how isostasy controls surface elevations? What are the main mechanisms by which heat is transferred through the Earth? What is meant by the geothermal gradient? What is a typical geothermal gradient near the Earth's surface? How does it change with depth, and why? What is a lithospheric plate? What are the plates made of? What is the ultimate source of energy that drives plate motions? How do we tell the size and shape of the plates, and where their boundaries are? What are the three types of plate boundary? Can you describe the main geological characteristics of each type of boundary? What are the main lines of evidence for continental drift? What is the relationship between the theory of continental drift and the theory of plate tectonics? What is a magnetic anomaly? What information do magnetic anomalies provide about plate motions? What is the definition of a mineral? What properties can be used to identify minerals? What are the different types of bonding in minerals? What is the essential building block of a silicate mineral? What is meant by the term polymorph? Can you give an example? Can you name some common silicate minerals? Some common non-silicate minerals? What do you know about the crystal structure of the following minerals: quartz, diamond, mica, halite, graphite? What is a rock? What criteria are used to distinguish and classify rocks? Where would you expect the following rock types to be formed? - granite, gabbro, peridotite, rhyolite, basalt, limestone, evaporites, sandstone, shale, conglomerate, slate, schist, gneiss, marble. Could you name at least one mineral that you would expect to find in each of the following rock types: peridotite, granite, evaporites, marble? How is the texture of an igneous rock related to its cooling rate? Can you name some common volcanic rock types and their plutonic equivalents? What are the main tectonic settings where magma is formed? Can you name three different reasons why melting occurs within the Earth? What are the different types of magmatic intrusion, and how are they defined? What are the main types of extrusive igneous rocks? What are the different types of lava flow and how do they form? What are the different types of volcano, and what controls their form and behavior? What are the main types of volcanic hazard? Which is the worst in terms of loss of life and property? How are sediments produced? What is meant by the sedimentary rock cycle? Can you name the different stages in the sedimentary rock cycle? What factor determines the size of grains in sedimentary rocks? What determines the shape of grains (round or angular) in sedimentary rocks?

What clues may be observed in sedimentary rocks that provide information about the nature of the environment in which they formed? What processes lead to lithification of sediments into sedimentary rocks? What is metamorphism? Can you name three different tectonic environments in which metamorphism occurs? What distinguishes the type of metamorphism in each case? Can you name at least one mineral that is characteristic of metamorphism? What type of metamorphism is represented by blueschist? eclogite? hornfels? What is cleavage in rock (and what is the difference from cleavage in minerals)? What is a slate? schist? gneiss? Can you explain the difference between tensile fractures and shear fractures? Can you define a normal fault? Reverse fault? Strike-slip fault? Thrust fault? How do these different types of fault relate to the different types of plate boundary? What are restraining and releasing bends? What type of structures are associated with each of them? Can you name three types of fault rock, and explain what they are? What is meant by the strike of a bed? The dip? Can you explain the difference between a syncline and an anticline? What is mean by an overturned fold? A recumbent fold? What is a dome? A basin?