Part 1. This exercise provides an introduction to ArcMap's interface and functions. You will learn how to load a default map view into ArcMap, turn thematic layers on and off, and modify the appearance of layers . The goal of the exercise is to create a map view which shows the location of water wells in relation to surface geology and roads for the Baldwin Park USGS 7.5 minute quad.
Note: It is a very good idea to read through these and all further instructions before you proceed with the exercises.
Before you begin the exercise, you need to clear your workspace, and then load the necessary data files. Double-click the "deltemp" icon on the desktop and answer "Y" if prompted. This deletes all files in the c:\temp\ directory. Next, copy all of the files from \\Geogsrv\data\Geog481-Carroll\proj1\ to the c:\temp\ directory.
The workspace now contains the proj1.mxd map document file along with the following geographic and attribute files in shapefile format:
Run ArcMap by clicking the Start button, then ArcGIS, then ArcMap.
After the ArcMap windows appear (select Blank Map if prompted), open the existing default view of the data set:
The map document file is used by ArcMap to store all the map and other settings that provide customized views of geographic data.
The default view contains only the shaded area of the Baldwin Park quad (USGS Topographic Quadrangle). This is probably the most boring map you have ever seen!
Before proceeding, take a few moments to familiarize yourself with the ArcMap display. The available data layers are shown in the list (known as the Table of Contents or TOC) on the left side of the map view window. The map space is referred to as a Data Frame. A map document can have numerous data frames. Data frames can have numerous layers. Various menus, buttons and tools are located across the top of the ArcMap display. Hover your cursor over the buttons/tools to see what they do. You will be introduced to many of these controls in the remainder of this exercise and in the ones which follow.
Your next task is to add additional layers of information to the Table of Contents. From the menu press:
The Wells layer is now shown with a default symbol in the Table of Contents. Note: you have not added the Wells.shp data to the map document file - only a reference to the data. The actual data remain in various data files on the hard disk. Both the map file and the data files must be present to work successfully in ArcMap.
Turning Layers On and Off for Drawing
Layers will draw when you 'check' the box to the left of the layer name in the Table of Contents. A layer will not be visible in the Data Frame window if its box is not checked.
There are at least two excellent reasons for turning layers off:
To view a multiple-layer map:
In order for the map to be accurate, a given location in the Wells layer must represent the identical location in the Geology layer and so on down the list. The only reason this critical condition is true is because all the geographic information in the individual layers was first converted into one universal coordinate system - in this case the California State Plane system. Move your mouse over the map and notice the coordinates in the lower right. Those aren't degrees of latitude and longitude. Can you tell what the units are in this coordinate system?
It is often necessary to alter the drawing order of layers to prevent larger symbols from covering smaller ones or area features from covering point and line features. For example, if you want to view the wells on top of geology you need to draw geology first. Otherwise the area shading of the geology layer covers the point symbols of the wells and makes them invisible.
ArcMap draws layers in the order they occur in the Table of Contents, beginning with the layer at the bottom and moving upward. ArcMap will try to order layers automatically when they are loaded to a map document beginning with polygons, then lines, and then point layers. However, you may need to change the default draw order. To change the order, you drag a layer name in the Table of Contents to the desired new location relative to the other layer names.
Choice of appropriate symbols, shading and colors is one of the most important steps when displaying spatial data. It is important to note that ArcMap assigns default symbols on a random basis. The odds of the default symbol being appropriate for the intended message of the map is almost nil. Fortunately, ArcMap provides a symbology properties window that allows you to change the visual qualities of data layers and quickly view the results.
Now choose a symbol and color to represent water well locations:
Separate symbol palettes are needed to express the different visual qualities of point, line and area features. When you click on a layer name, ArcMap notes the feature type and presents you with the correct palette.
Part 2: The next part of the exercise introduces additional techniques for creating a thematic layer map using ArcMap. You will use the layer properties dialog, and the distance, search, zoom, annotation and graphics tools to produce a customized view of the data. The final view will contain a geology map and a graphic symbol identifying the location of a proposed well at the intersection of Azusa Ave and Interstate-10. The map will show all wells in the vicinity of that location with their TDS values listed next to them. As you work through the details of the exercise, keep in mind the overall strategy (or sequence of operations) needed to create the desired map view.
Before proceeding, you should set a more descriptive title for your data frame. You should also identify the linear units of the map so that later you can obtain distance measurements and establish a map scale.
Map units refers to the units used for the XY coordinates of the map. Display units refer to the units used for reporting distances across the map.
Introduction to Thematic Mapping
The first step in creating your thematic map is to create a surface geology layer to serve as a background for the well data. With a uniform color for the Geology layer, the map is simply telling you that 'geology is located here' much the way you might say 'wells are located here' or 'freeways are located here'. This works for wells and freeways, since they are not ubiquitous features (present everywhere) the way geology is.
To convey meaningful information about geology, you need to have separate colors for each rock type. Because the geology database already contains information on rock types for different areas, you can use that information to control the color symbols of your map.
Default colors are now assigned to each of the four rock types.
When you are satisfied with the cartographic quality of your map, dismiss the layer properties dialog by clicking OK.
Features and Attributes
A key concept in GIS is the link between features and attributes. In addition to 'Rock_code' each of the features (polygons in this case) in the geology layer has additional attributes. What is the area of the smallest rock unit in this layer? What is the 'Rock_Type' of this feature? To find out:
Querying the Database to Find a Location
Because the map is linked to an attribute database, you can use the query function to locate the intersection of Azusa and I-10. The Query function is also referred to as 'Select by Attribute.'
After a few moments, Azusa Ave should appear highlighted in light blue on the map.
Repeat the operation searching for Fwy_name = "San Bernardino" in the Freeways layer. Remember to select the appropriate layer before attempting to query it. The intersection of the two roads is shown where the two light blue lines cross each other.
Note: If you used light blue for one of the colors in your Geology layer, you might not be able to see the light blue highlighted roads or freeways on the screen. Either un-check the Geology layer to make it invisible or change the color to something other than light blue.
Now you are ready to define a "zoom window" around the intersection of the two roads. The zoom window you will create is defined by the opposite corners of a rectangle, where one corner is northwest of the intersection and the other southeast of it.
You should see the eight wells that are located in the vicinity of the intersection. If you mess up, use the Zoom Out button or the 'Go back to previous extent' button and try again.
In addition to searching and sorting attributes, you can also use attribute values for labels or annotation. Use the information in the TDS field to add TDS values next to each of the wells in your view. First, you must open the layer Properties and identify which attribute field is to be used for your labels:
To add the labels to the map:
The location of the labels is based on rules set in the layer properties dialog. Don't worry about trying to move them at this point.
Adding Freehand Graphics to the Map
The final two tasks are to add a square symbol at the northeast corner of Azusa and I-10 (San Bernardino Freeway) and label it with the text : "New Well Site".
If you don't like the location of the symbol, activate the Select Elements tool, click on the graphic to select it, then press and drag to a new location.
The text used to label the well features came from information in the database. Often it is useful to add text as a freehand operation unrelated to layer features. At this point, use freehand text to label the new well site:
When finished:
Follow the same freehand procedure to label the San Bernardino Freeway and Azusa Avenue. Experiment with rotation (the 'Angle' box in the properties dialog) to align your text. Remember, if you don't like the initial location, you can select text and drag it to a new location. Similarly, if you don't like the rotation, you can right-click the text, open the properties dialog, and enter a new rotation value.
Before continuing, check to see that there are no selected (light blue) features in any of the layers:
Or, if you know you want ALL selected features on the entire map to be cleared:
Part 3. The third and final part of the exercise introduces the concept of the map layout in ArcMap. The layout represents a page where various map components - data frame(s), title, legend, scale - are arranged into a cartographic document. The goal of this exercise is to create two separate map layouts, each relating to a different aspect of the mapping project.
Note: It is assumed that students in this class are familiar with accepted cartographic terminology, conventions and design principles. If you have not taken a cartography class (e.g. Geog. 281), you may wish to review a classic introductory cartography textbook such as Principles of Thematic Map Design by Borden D. Dent. A copy is available in the CSUF Library (GA105.3 .D46 1985). You might ask any of your classmates that still have their cartography books to borrow their books for review.
To create a layout:
Doing so will change the contents of the map window so that your map appears on a virtual sheet of paper.
The layers of your map appear in a 'data frame' on the page. This data frame is one of many possible map elements that can be added to this Map Layout. Other elements might include a title, north arrow, scale bar or other data frames.
The Layout toolbar should also be floating somewhere on your map. Move it to a convenient place for now.
Next, define various properties of the on-screen layout and the printer page it represents:
Set the following:
Snapping elements to the layout grid allows you to align features easily. If the snapping bothers you, try turning it off later.
The map elements in the layout view are contained in various types of graphic frames. To reposition or resize any page element simply:
Since you will be adding other map elements to your layout, you should reposition and resize the data frame.
If you are happy with the size, shape and position of the frame, you are ready to add the other map elements.
Now add additional map composition elements to the page:
When you are satisfied with your work, save your map to the Proj1.mxd file by selecting Save under the File menu. Pressing the Disk icon on the Button Bar accomplishes the same thing. Note: Some software applications can be set to periodically save your work so that in the event of a power failure or computer crash much of your work will be recoverable. ArcMap is NOT one of those programs. To avoid "excitement" you should regularly save your work.
So that you do not overwrite your first layout:
Now all future changes will be saved to the new file.
The page orientation changed, but your map elements did not.
Experiment with the various design elements until you have 2 map compositions (one portrait and one landscape) that present your data in an effective manner.
Regardless of what computer you are working on, it is a good idea to backup your work somewhere other than in the c:\temp\ directory so you don't delete important work.
This is a typical work flow for backing up your work to another location:
Later, if you want to work with the map you've created, you would clear out the c:\temp workspace and copy all the Proj1 files from <drive>:\proj1 to c:\temp.
Be prepared to show both your Proj1 map (portrait orientation) and Proj1_landscape map (landscape orientation) to your instructor or lab assistant for assessment.
You do not need to print anything for this project.
Last modified 08/31/2021