Module 4 Understanding Maps


Learn about maps and mapmaking. Find out what kinds of maps are used in undersea exploration, and especially those that will be used during the PROWL expedition.


To a geologist, maps are one of the most important media for conveying information. We make maps to organize the data we collect, and we use maps to tell everyone else what we found. Mapmaking and map interpretation are essential skills that all scientists must master. Learn about the different maps scientists use and what makes them unique, and especially about the maps we'll be using as we study the Puna Ridge.

This module employs links to Puna Ridge web site Science Factoids  (Map Navigation, Transponders, GPS) and to the U. S. Geological Survey's Learning Web on Maps to learn about maps and mapmaking.

In the next learning module, Geological Interpretation of Sonar Data, we look at the maps we are making during our research cruise, and discuss how we make geological sense out of the images we see. This module will be presented "live" as a series of lessons that we are posting from sea as the data come in.


1. What are maps? What are they used for?

Maps are representations of things that are much larger in size. They are usually drawn on paper so you can spread it on a table and see for example, all the roads in city of Los Angeles, or the political boundaries of Europe, or even the topographic relief of the Andes mountains in South America. There are many types of data that can be represented on maps -- road maps help us to navigate through cities and towns, topographic and trail maps guide us through the wilderness, satellite weather and rainfall maps tell us whether it is a good day to go to the beach or stay home and watch TV, and political, population density, and land use maps tell us something about where people live and what parts of regions are urban, agricultural or industrial. Finally, when we sail and study the oceans and the seafloor, we use maps which summarize sea conditions, the distributions of surface currents, and the seafloor topography.

R/V Thompson Berthing Map
Map of the R/V Thompson showing the location of the sleeping cabins and which scientists are sharing rooms.

Maps are used to help us locate where things are, to navigate from one place to another, and to inform by summarizing the characteristics of any single topic or subject area. Maps tell us where we are - where something is located. Now go to the USGS Learning Web to read about the concept of location and how we know where we are.

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