When solving various technical problems there is a need for automatic and sufficient fixation of underwater objects. The most effective method in this case is sonicolocation (hydroacoustic).

Currently in the USSR more than 75% of the volume of rock mass of placer deposits is processed by dredges. The plans of development of the national economy and the next few years will see a significant increase in dredge construction, especially through the commissioning of powerful dredges (380, 400, 500 m) deep digging...

When applying sounding equipment in surveying work naturally arises the question of its accuracy and, therefore, the possibility of using it to solve specific engineering problems. At the present time - in the period of development and formation of sounding method of measurements in surveying - this issue is of particular relevance.

Over the past decade, ultrasound has found wide application in a number of branches of science and technology due to its special properties. Ultrasonic waves are used in testing of materials (defectoscopy), processing of materials, signaling, determination of distances and directions (sonicolocation - echo sounder), in medicine, food industry, etc. Currently, there is almost no branch of national economy, where ultrasonic waves would not be used.

Orientation of mines is one of the most labor-intensive and responsible tasks of the surveying service. The production of magnetic orientation does not require stopping the mine shaft either during the preparation period or at the time of production. Magnetic orientation has a number of important advantages (see article). The accuracy of magnetic orientation, as is known (at this stage of study of this issue), does not depend on the depth of the mine. In addition, all sources of errors (in determining azimuth) that accompany geometric orientation are eliminated. Practice in the production of magnetic orientation here and abroad shows that if the work is carried out thoroughly and all required conditions are met, magnetic orientation guarantees an accuracy of 1'-2' and even higher. This is also evidenced by the results of our work described below. In our work, we make an attempt to analyze some of the issues raised above, based on an analysis of field observations we made in 1937 at the Novaya Golubovka mine.