1 / 11

Basic Map Reading

Basic Map Reading. Grid Coordinates (4, 6 and 8 Digit). A map is a graphic representation of a portion of the earth’s surface drawn to scale, as seen from above; it uses colors, symbols and labels to represent features found on the ground. Definition of a Map. (review).

matha
Download Presentation

Basic Map Reading

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Basic Map Reading Grid Coordinates (4, 6 and 8 Digit)

  2. A map is a graphic representation of a portion of the earth’s surface drawn to scale, as seen from above; it uses colors, symbols and labels to represent features found on the ground. Definition of a Map (review)

  3. A series of straight lines intersecting at right angles forming squares Horizontal grid lines run grid west to grid east Vertical grid lines run grid south to grid north Grid Lines BASIC RULE Read right on the vertical lines, then up on the horizontal grid lines

  4. Grid Lines 22 21 20 19 3818000mN 47 48 49 50 51 52 53 54 546000mE

  5. Grid Coordinate A grid square’s coordinates are found by combining the values of the vertical and horizontal grid lines that intersect at the lower left hand corner of the grid. A 4-digit grid coordinate locate a point to within 1000 square meters A 6-digit grid coordinate locate a point to within 100 square meters A 8-digit grid coordinate locate a point to within 10 square meters

  6. Finding a 4-Digit Grid Coordinate 23 GRID REFERENCE: 4820 22 21 20 19 3818000mN 47 48 49 50 51 52 53 54 546000mE

  7. Grid Coordinate Scale A grid coordinate scale divides the grid square more accurately and consistently than estimation Coordinate scales: ° 1:25,000 / 1:250,000 ° 1:50,000 ° 1:100,000 A 1:25000 coordinate scales divides the 1000 square meter block into ten 100 meter divisions, the ten divisions are further divided into 20 meter blocks

  8. Grid Coordinate Scale

  9. Finding the Grid Coordinate of a Point • First determine the grid square the point is in. This gives 4 digits: 12xx56xx. • Next, using correct scale on protractor, align the bottom right corner of the protractor scale to the bottom right corner of the grid square. • Slide the protractor to the left until the right edge of the scale intersects the point. • Read off the horizontal and vertical position: • 12345678

  10. 23 22 21 20 19 18 46 Grid: 49551885 Gives second two longitude (horizontal) coordinates: 85 Gives second two latitude (vertical) coordinates: 55 47 48 49 50 51 52 53 54

  11. Plotting a Grid Coordinate • Grid Coordinate 12345678 • Divide into horizontal and vertical measurements 1234/5678 • Next locate primary coordinates that give grid • square: • ° 12345678: 12 and 56 are primary • coordinates that provide the grid square • ° The 34 and 78 are determined by using • the tick marks on the protractor

More Related