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Introduction to Map Making
Prof. Dr. Sajid Rashid Ahmad
Atiqa Ijaz Khan _ Demonstrator
Map
• “Amap is a graphical representation or scale model of spatial concepts.”
• “It is a graphical representation of a real 3D world on a 2D surface.”
• “A map is a model of Earth at reduced scale.” (ESRI)
• According to the International Cartographic Association (ICA), a map is arepresentation, normally to scale and on a flat medium, of a selection of materialor abstract features on, or in relation to, the surface of the Earth. (Book)
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Friday, December 26, 2014Institute of Geology, University of the Punjab
4Maps by Muslims
The World Map of Al-Idrisi (12th
Century). South is on Top.
Al-Masudi’s Atlas of the
World
Importance of Maps
• Map’s significance can be determined from the following:
• A good way of recording and storing information.
• A method of communicating with users using symbols at reduced scale.
• Helps in the recognition of spatial patterns around us.
• Establishing the relationship between spatial patterns.
• Visualization of spatial patterns with elegant designs and themes.
• Analysis of spatial patterns.
• Graphically representation of findings that are verbally complex task.
• Helps in understanding the locations where it is not possible to go anywhy.
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Criteria of a Good Map
• A good map should fulfills the following terms:
• It should be understandable to readers.
• Its goal or motive should be clear.
• Map should depicts for its audience.
• It has the beauty and elegance.
• It is on standards to display its contents.
• It displays the available information precisely.
• It should not cost time and money.
• it should fulfills its purpose of making.
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Types of Map
• There are many types of map
• Geological Map
• Reference Map
• Thematic Map
• Environmental Map
• Bio-geographic Map
• The most important types are:
• Reference Map
• Thematic Map
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Types of Map
Reference
Topographic
General Purpose
Thematic
Statistical
Geological Environmental
Reference Map
• Reference maps gives general information about the location of features.
• Depict the relief-displacement (elevation) of the topography (surface).
• Defines the general trend an d form of the surface.
• Shows roads, buildings, boundaries, etc.
• Examples:
• Topographic maps
• Road atlas
• These maps are a reference tool, showing the outlines of selected natural andman-made features of the Earth, often acts as a frame for other information.
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Friday, December 26, 2014Institute of Geology, University of the Punjab
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Reference Maps for Pakistan
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Thematic Map
• Thematic map shows the distribution of a specific topic.
• Represents the spatial dimensions of a specific phenomenon.
• It may represented by one or more than one variables, like:
• Population, income, diseases, language, religion etc.
• It is represented by:
• Colors, symbols, shapes, patterns, shades of colors, texture, density, etc.
• Used for:
• Analysis of data
• Presentation of data
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Thematic Maps for Pakistan
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Map Elements/Components
• Map elements are:• Title of the Map (Content/Purpose)
• Scale of the Map (Measurement)
• Legend of the Map (How to read/interpret)
• North Arrow (Orientation/Directional Indicator)
• Map Body
• Inset Map
• Logo
• Publisher of Map
• Cartographer Name
• Date and Time
• Source of Data (Reference)
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Title of the Map
• The most important element of the map for acquiring information efficiently is thetitle.
• It is essential, for a map, to have a title.
• The title identifies the map area and the type of map.
• It is usually the large font size on the sheet, often written in caps.
• This is to ensure that the readers knows what is being mapped.
• Cartographers may list the title simply or artistically.
• It should clearly indicate the purpose of the map.
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Legend of the Map
• Information needed to read a map is found in the map legend.
• Most maps use symbols or colors to represent different geographic features.
• The map legend helps determine what the symbols and colors mean.
• Without legends, map symbology is virtually meaningless.
• It is like a dictionary, used to understand the meaning of what map represents.
• It is used to link non-spatial data with spatial entries.
• It essentially provides valuable information for interpreting what it is a mapshowing.
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Friday, December 26, 2014Institute of Geology, University of the Punjab
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Scale of the Map
• Almost all maps have scales.
• “Scales compare a distance measured on the map to the actual distance onthe surface of the earth.”
• Scales appear on maps in several forms, but most cartographers draw a linescale as a point of reference.
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• High Details
• Small area
• 1:24,00 or larger
Large Scale
• Average
• 1:24,00 – 120,000
Medium Scale
• Less Details
• Large area
• 1:120,000 or smaller
Small Scale
Types of Scale
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Small Scale Large Scale
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Large Scale
• Objects are relatively larger in size.
• With High details objects.
• Covering the Small area.
• High RF factor.• 1:24,000; 1:50,000 etc.
• But, smaller denominator.
Small Scale
• Objects are relatively smaller in size.
• With Low details objects.
• Covering the Large area.
• Small RF factor.• 1:250,000; etc.
• But, larger numerator.
Don’t Ever CONFUSE it again… !!!
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Ways to Depict Map Scale
Scale
Verbal Scale Written Scale Scale Text
Fractional Scale
Representative Factor
R.F.
Graphical Scale
Linear Scale Scale Bar
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Representative ScaleScale BarStatement of Scale
Ways to Depict Map Scale
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Calculating the Map Scales
Scale = Distance on map / Distance on Ground
For Example:
Scale = 1.27 inches / 5 miles
S = 1.27 inches / 316,800 inches
S = 1 / 250, 000
So…… Scale is: “1 : 250, 000”
Practice:
Scale = 2 cm / 1 km
S = 2 cm / 100,00 cm
S = 1 / 50, 000
So…… Scale is: “1 : 50, 000”
Directional Indicator
• A directional indicator on a map helps determine the orientation of the map.
• It is costume to place a north arrow at the Top.
• A north arrow element maintains a connection to a data frame.
• When that data frame is rotated, the north arrow element will rotate with it.
• It can be simple or complex.
• In history, north arrow was also displayed on the South…!
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Types of North Arrow
• There are three types of North arrow:
• True North (TN):
• Also known as ‘Geographic North’.
• It is the geographic north of the Earth.
• As referred to lat / long.
• Magnetic North (MN):
• The north as define by the Earth’s magnetic field.
• Grid North (GN):
• By the vertical lines of the map projection.
• Like UTM vertical lines.
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Inset Map
• Inset maps are smaller maps on the same sheet of paper.
• Inset maps provide additional information not shown on the larger map.
• Inset maps are drawn at a larger, more readable scale.
• Inset maps usually feature areas of interest related to the larger map.
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Friday, December 26, 2014Institute of Geology, University of the Punjab
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Inset
Map
Map Body
• Actual face of the map displaying features, symbols, and other information on themap.
• Map itself should have all the necessary amount of data and detail.
• Information should not be too much that causes confusion
• Nor be too short making map useless.
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Balancing of a Map
• Refers to the arrangement of elements within the overall composition.
• All the elements of map should be equally distributed within the whole page.
• It should not grouped to side of a page.
• Researchers shows that, map elements should be centered along the ‘Visualcenter’, of the viewer, rather than the ‘Geometric center’ of the objects.
• As it attracts more to the eyes.
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Errors
Hierarchy of the Map
• It refers to the order of importance of map elements.
• The most important features should be highlighted the most.
• As it is going to effects the visuals of viewer’s eyes..
• Generally, map should attracts its viewer as a whole.
• But, there are few of the elements, that should be arranged or highlighted in away as to attracts the its users.
• Title of the Map
• Scale bar
• Map body tone and color
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Friday, December 26, 2014Institute of Geology, University of the Punjab
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Map Accuracy
• Then human drafting errors will occur and can be compounded by the quality ofour source maps and materials.
• A map accurate for one purpose is often inaccurate for others since accuracy isdetermined by the needs of the project as much as it is by the map itself.
• Some measurements of a map’s accuracy are discussed below:
• Absolute Accuracy
• Relative Accuracy
• Attribute Accuracy
• Completeness
• Currency
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Types of Map Accuracy
• Absolute Accuracy:
• Relationship between geographic position on a map to its real position on thesurface of the Earth.
• It is required for extensive surveying and engineering application.
• Relative Accuracy:
• Refers to the displacement between two points on a map compare to the samepoints of the real surface of the Earth.
• Attribute Accuracy:
• Refers to the accuracy of the attributes linked to the map’s feature.
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• Completeness:
• Refers how much data it contains as required by the users.
• But, it is not for life time.
• As the map gets older, it becomes less complete.
• Currency:
• Refers how upto-date a map is.
• It is usually expressed in terms of revision date.
• Means how much data is added after how much time.
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