Boulders - traces of deposits

Blue lakes, rivers with the purest water, rides and waterfalls, beautiful coniferous and birch forests... All this is seen by geologists with their own eyes during their hiking and stops. What's so unusual? The experienced tourist will ask. The thing is, what geologists do during all this. Sometimes they are engaged in a business that from the outside may seem mass eccentricity - diverge in different directions and so, alone, spend hours wandering around. It turns out that in this way they are looking for... boulders. All because boulders - traces of deposits!

It turns out that in this way they are looking for... boulders. All because boulders - traces of deposits

In order to better understand why and why geologists are engaged in this matter, we need to start talking about... the great glaciation that was in the Quaternary period. But what does the ancient glaciers have to the work of geologists?.. One hypothesis helped, which was confirmed by facts, practical work of prospectors.

The ancient glaciers moved slowly, continuously, and, like giant bulldozers, pulled pieces of earth from the earth's solid rocks, dragged behind them hundreds of kilometers. Those rocks, as a rule, were underpinned or covered, in a word, somehow adjoined in the distant past with ore. For millennia, ore deposits were covered with a thick layer of soil, disappeared from the eyes of geologists. Millennia of rain and snow, wind and sun so treated boulders that they now represent almost rounded blocks. And only the experienced eye of the geologist will discover in the valleys, on the cleft, in the cracks, foreign inclusions - traces of the former contact with the ore. These are some traces of deposits and can prompt the way to underground storerooms.

Boulders, as is known, are scattered by glaciers on a vast territory. Suppose a trail of sulfur pyrite was found on one boulder, a few kilometers from it, on the other, even further, on the third... on the thirtieth the same. These tracks should lead to an ore deposit, only traces should be found as much as possible. And this requires a lot of people, it is necessary to walk more than one hundred kilometers, not one region to look across and across, and to survey not one hundred, and even a thousand boulders. In addition, from boulders, on which traces of ores are seen, scrape off or beat off hammers, and mark the exact places of these stones on a large-scale map. Samples carefully packed in polyethylene bags, bags to seal in envelopes and put numbers corresponding to the numbers of boulders.

And how among these innumerable traces left by glaciers, to find, calculate the path leading to the deposit? Then on the map of the search area - and this is not a job in the field, but in the laboratory, experienced geologists are engaged in it - a transparent tracing paper is superimposed on which lines of glaciers are plotted along the same scale. These lines are not parallel - the width of glaciers spreading from high latitudes did not remain constant. Moving to the south, the glacial tongues always expanded, causing the boulders that they tore from one place to be scattered along the front of its movement for many kilometers.

The work of the geologist is now to move the boulders with traces of ore back to the place where the glacier pulled them from. All tracks, as a rule, converge to a point. At this point, you should look for an ore deposit. In this unusual way, many ore deposits have already been discovered.

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