Lab2 - Name SID Lab 2 Maps Geological Structures Relative Age Determinations Introduction Maps can be some of the most interesting and informative

SID: Lab 2: Maps, Geological Structures, Relative Age Determinations Introduction: Maps can be some of the most interesting and informative printed documents you will ever see. Most of us are familiar with simple maps that indicate places and the roads you take to get from one place to another, but maps can convey many kinds of information. In this lab we will learn to interpret two very important maps used in geology and related disciplines: topographic maps and geologic maps. We will also learn to interpret geological structures, and learn how they can be inferred from geologic maps Objective: This laboratory is to introduce you to topographic and geological maps, cover some geological structures associated with folding and faulting of rocks, practice making relative age determination of rocks and structures, and have you construct a geological cross section based on information presented on maps. Answers: Please answer the indented, numbered questions below on THIS LAB – you will turn in this document . Explanations should be concise; most questions can be answered with a few words, or a sentence or two. All answers should be your own, but we encourage you to discuss and check your answers with 2-3 other students. Discussion and explanation are terrific ways to learn! Labs are graded out of 100 points, and then scaled accordingly. -------------------------------------------------------------------------------------------------------------- Part 1: Topographic Maps Topographic maps are maps that provide information regarding the surface of the earth. The main feature of topographic maps is their representation of topography : ridges, valleys, mountains, plains and other earth surface features, natural as well as man-made. Elevation is depicted on topographic maps by the use of contour lines . Contour lines are lines representing equal elevation across the landscape. Contours are drawn at regular intervals of elevation; these intervals vary between maps, but are typically specified at the bottom of the map or in the map legend. In addition, topographic maps provide a wealth of information regarding both natural and manmade features (see the topographic map symbol key). Map scale is a critical piece of information on all maps. Scale is the value that relates a map to the real world. The scale of a map allows the user to translate distances on the map to distances on the ground. For instance, a map with a 1 to 12,000 scale (1:12000), tells us that for every unit of measure on the map, 12,000 of those units on the ground are being depicted. With any map, the detail of features illustrated will depend on the map scale. Study the topographic map showing the region of San Francisco (this map is also available online at: http://tinyurl.com/2r9csg ). 1) What is the scale of this map? (1 pt).