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Show ON THE PUBLIC DOMAIN, PROGRAMS MUST OFTEN PROCEED WITHOUT THE BENEFIT OF EITHER TOPOGRAPHIC OR GEOLOGIC MAPS IN THE MAPPING PROCESS MANY OF THE MOST IMPORTANT RESOURCES OF THE COUNTRY HAVE BEEN REVEALED THE ESSENTIAL FEATURE OF THE NEEDED MAPPING PROGRAM IS ACCELERATION Essential Features of an Accelerated Federal Surveying and Mapping Program The effective use of the surface of the earth and its resources requires extensive and, for certain purposes, detailed knowledge of the physical and geologic character of the materials of which it is formed and of its topography. These physical charac- teristics are best portrayed on maps which show the variations in elevation and the geological characteristics of the materials forming the surface and sub- surface structure of the earth. The availability of topographic maps on which contour lines ( lines of equal elevation) showing surface characteristics and geologic maps showing both the basal hard- rock geology and the surflcial characteristics of the accumulated weathered soil mantle make special survey unnecessary for each intended use. The making of satisfactory maps for these purposes requires specialized talents and the detailed surveys usually are beyond the resources of any one type of map user. Topographic and geologic maps of general usefulness have generally been provided only in those areas where the United States Geological Survey, acting alone or in cooperation with other Federal and State agencies, has been able to map under a limited program. The maps made by other agencies, primarily private corporations, are either unavailable to the general public or the maps are unsuited to other than the specialized uses for which they were made. After almost 100 years of mapping, not more than 25 percent of the surface of the United States has adequate topographic maps, and only 10 percent has satisfactory geologic maps. Mapping, however, is very unevenly distributed over the country. A few States are almost complete; in others the program is rapidly approaching completeness. Unfortunately, however, many sections of the country - and especially the West - fall far below the average. On the public domain, where the Federal Government has special responsibility for the activity in mineral resources, forest and grazing management, and extensive reclamation and headwaters control projects, such programs must often proceed without the benefit of either topographic or geologic maps. Throughout the country various other Federal activities, principally those of water resources management, erosion control and reforestation, are also handicapped by the scarcity of satisfactory maps for guidance. In all cases there are impelling and logical reasons for reversing these relations by providing adequate maps prior to even the planning of resource development. Without these maps conclusions as to effective use of resources and proper structures must proceed without adequate information. It is in the mapping process that many of the most important resources of the country have been revealed, and the characteristics of the earth's surface and subsurface can only be made known through proper mapping. The geological features are often so complex that mistakes, some extremely serious, will continue to be made on projects planned and completed without maps. Evidence is rapidly accumulating of wasted funds on projects that were planned and carried out with inadequate basic data and maps. Much of the mapping program now under way is directed to project areas where major plans have already been formulated and in many cases actual construction is under way. This tardy development of adequate maps can only serve to alleviate in part the mistakes inherent in plans made without maps. The rapid development of the American economy has now brought into use most of the land surface of the country. The progressive intensification in the uses of land for multiple purposes would seem to establish the need for a mapping program 13 |