The Daily Alaska empire., 1934-01-28

AoA OOPOSt oPlO AidppliiS 10 AOuA times as large GIG times the area) as that used in Alaska for it's reconnaissance type of surveys and less than l per cent of Alaska has been mapped with the degree of detail that is considered standard for most of the work in the States.
 This topographic mapping while undertaken primarily in the inter est of the mineral resources inves- tigations is of great use in all phas- es of Alaskan development so that maps are in constant demand by those having to do with the selec- ton of routes for roads or trails, for determining distances and di- rection between points, for avia- tors, trappers, hunters, naturalists, tourists and to serve as a base on which to trace out or follow the distribution of pl an ts, animals, rocks or any of the other natural resources of the region they cover. These maps are especially useful because they show not only the distribution and relation of the surface features correctly as though projected on a horizontal sheet but they also, by a system of lines called contours, indicate the height above sea level of every part of the area covered by the map.
 Deposits Are Indiuidual
 Knowledge as to the kind, distri- button, and extent of the mineral resources in a pioneer region can not be acquired by any quick or easy method and there is much more than a grain of truth in the often quoted saying that gold is where you find it." However, while each deposit has certain individ- ual characters and differs from all others, just as no two people are identicals there are certain principles that have been found to be generally applicable and even the differences may be found to change in a determinable way in response to variables in their mode of origin or location. In this field as in so many others experience is the best teacher" and the new must be interpreted in the light of the known. Thus, the study of ore deposits of diverse types in many mines throughout the world have furnished geologists with a great body of facts regarding favorable and unfavorable factors in the for nation of ore deposits.
 With this background the geolo- gist, if skilled, can examine tracts and apply this knowledge in reach ing a wise prediction as to the liklihood of it's mineral value. Such a geologist must necessarily be constantly on the alert to note all the pertinent local conditions that may have a modifying influence on the problem for small differences in even some of the minor factors may produce entirely discordant results. For instance, stream that has certain velocity may effect a high concentration of placer gold where as with a higher velocity it would sluice out that concentration or would fail to effect profitable concentration if it's velocity drop ped too low
 Minerals Are Associated
 So, too, different types of min erals are usually associated more or less closely with certain geologi- cal processes or conditions. To de- termine what and how these dif- ferent geologic factors were in different parts of Alaska and their effectiveness in producing mineral deposits of commercial value has been the object of the Alaskan Branch of the Geological Survey in it's conduct of extensive surveys throughout the Territory. In the course of these investigations the geologists determine the kinds of rocks in the areas in which the surveys are conducted, what min eral deposits occur there, and so far as possible their extent and the processes that have led to their formation. if -s-fi tffft
 In the course of this field work all the prospects are studied care fully for by noting and interpret ing the conditions shown by them the geologist gains a knowledge which enables him to recognize and predict regarding areas that war rant exploitation even though val uable deposits have not then been discovered in them. Work of this sort has been done by the Survey geologists covering about half of the area of the Territory, in the course of which every mining camp that has been productive has been studied and mapped more or less thoroughly and several hundred reports, most of which are accom- panied by maps and other illus trative material, have been pub lished and widely distributed.
 Many Reports Free
 A great number of these reports are distributed without charge or may be freely consulted in prac-