A. Silva compass1. A Silva (or equivalent) compass is required for measuring and drawing bearings. Unless you know the declination of your map area, set the compass declination to 0°. (The arrow for true north can be added once your declination is known.)
B. Tape AND/OR pace1. If you are using a tape ONLY then you will map in feet or meters depending on the units of your tape. For this course meters will be used.
2. If you are using your pace ONLY then map in paces. Do not convert you pace in the field unless absolutely necessary; doing so can waste valuable time and can introduce error if you are in a hurry and make a mistake. A single conversion calculation can made later and indicated on your map by a bar scale.
*3. If you are using BOTH tape and pace then you will need to convert your paces in the field in order to maintain consistency. If however, you only use the tape to set up a baseline then record the baseline measurement in both meters and paces and map in paces.
The method you choose will depend on the degree of accuracy required (tape recomended) and time constraints (pacing is quicker). A proficient mapper may be able to quickly and accurately map a beach by pacing from a precisely located and measured (taped) baseline or grid.
C. Lined paper or graph paper1. Lined paper (single ruled or graph paper) is necessary to accurately plot your bearings with a silva compass. You will designate a set of N-S lines on your paper. (See Part II-A.) After taking a bearing place your compass on the paper so that the compass meridian lines on the transparent bottom of the compass are parallel to the N-S lines on your paper. Only one set of lines is necessary so regular lined paper may work as well, if not better, than graph paper. However, the disadvantage of using single ruled paper is that you have to orient the narrow width of your paper in the N-S direction. If your beach is elongate in the N-S direction you cannot take full advantage of the length of the paper and you may need more than one sheet.
2. Don’t use the grid cells on graph paper to measure distance. Use one of the rulers on your compass. If the ruled lines on your compass have worn off you will need to carry ruler.
A. Determining the size and orientation of your map1. Quickly pace the map area to determine its size and dimensions.
2. Identify the orientation of the beach relative to north. Determine how the beach will be oriented on the paper. Draw in your north arrow. (This will be magnetic N. True north is several degrees to the east.)
3. Determine how much detail you want to obtain, the scale of your map, and the size of the paper required. You may need more than one piece of paper.B. Setting up a baseline/grid
1. Using a tape and flaging rods, set up a single-, two-, or three-lined grid along the length of your beach. How many lines you use depends on the beach’s width. All rods should be spaced at a constant distance (5 or 10 meters apart) from each other, and should be aligned. All grid line must be straight and parallel.
2. Record the bearing, length (in meters and paces), and exact location of the principal baseline in your notebook. If you plan to remap the beach then your baseline/grid should be located by one or more permanent markers.
A. Map the grid on your paper.
B. From each grid node, pace or tape to water line and to the outer limit of the back shore. Locate and draw in all major beach features, such as berms, seawalls, dune scarps, cusps, the beach face, the low tide terrace, etc.
A. Place the following information on your final map.
1. Scale in meters (bar and verbal).B. The final map should have only the features mapped. All bearings and gridlines must be removed.
2. North arrows; magnetic and true north
(look up the declination on the most recent quadrangle map)
3. Title
4. Name of mapper(s)
5. Date
6. Mapping method (tape and compass, pace and compass, or combined pace/tape ane compass)
C. Features to note on your map:1. backshore
2. berm(s) :storm berm, spring tide berm, active berm
3. beach face
4. low tide terrace
5. cusps
6. high tide swash
7. rill line (line of ground water discharge)
8. ridge and runnel/ bar and trough
9. bedforms: ripples (indicated flow direction?), antidunes, rhomboid ripples, swash marks, etc.
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