Practically all descriptions of well locations refer to township, range, and 

 section lines; and if these lines are not shown on the map, it is difficult to de- 

 termine the correct locations. On very small-scale maps, township lines may be 

 undesirable; but, since county lines are tied in to the "land net," they may be 

 shown. It should be borne in mind that geographic coordinates are not lines 

 surveyed and marked on the ground, but, rather, are the framework of the map 

 projection. The subsurface geologist is concerned primarily with legal sub- 

 divisions of state and federal surveys; and all points of control will be located 

 on the map by means of these surveyed lines. 



Figure 24-56 illustrates the basic principles of the township system of land 

 surveys. There are many deviations from these principles, but ordinarily only 

 small areas are involved. In western Canada all townships are numbered north, 

 beginning with township 1 at the international boundary. All ranges are east 

 and west of one principal meridian located in the eastern side of Manitoba. 

 Guide meridians are spaced about 30 townships apart and are numbered 1st, 

 2nd, 3rd, etc., meridians west. 



Figure 24-57 shows the numbering of sections in United States and Canadian 

 townships, and the subdivisions of the sections. Townships in Canada, like 

 those in the United States, are composed of 36 sections, each approximately 

 one mile square and containing 640 acres. The numbering of the sections is 

 shown in the figure cited. 



The Canadian system of designating the subdivisions of a section is more 

 convenient than ours. The 1/16-seotion (40-acre) tracts are numbered from 

 1 to 16 according to the Canadian plan of numbering sections in the township. 

 These subdivisions are called Legal Subdivisions, abbreviated Lsd. Thus, the 

 shaded portion in the section diagram is described as SW14 of Lsd. 12. Accord- 

 ing to our system the same tract is described as the SW14 of the SW14 of the 

 NW14, or SW SW NW. The location of a well situated at a is described as 

 follows: SW SW NE SWJ4 of section 10. In Canada the description (at 6) is: 

 SW SW Lsd. 6 of section 10. 



For a number of years it has been common practice in western United 

 States to make the footage location of a well according to multiples of 330 feet 

 from surveyed land lines. Thus, a location described as 1650 feet from the west 

 line and 1650 feet from the south line of section 10 would be in the SW SW NE 

 SW14 of the section, or the location of a in Figure 24-57. 



Well-spotting templets, made from acetate of about 0.020 inch thickness, 

 greatly facilitate the posting of maps. The templet is made with inked lines 

 corresponding to the land lines shown on the map, with holes punched at the 

 normal positions of well locations. The templet is registered over the land lines 

 on the maps and the well is spotted by inserting a sharp pencil in a hole at the 

 correct location. 



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