Measurement of the difference in the Earth’s gravitational potentials with the help of a transportable quantum clock

The results of the Russia’s first ground-based experiment for determination of the difference in the Earth’s gravitational potentials on the basis of the measurement of the gravitational effect of the time delay with the help of a high-stability transportable atomic clock are provided. The reference atomic clock was placed in Moscow oblast, and a transportable quantum clock with an instability of 3 × 10^–15 was placed in the Caucasus Mountains, with a difference in height of the clocks of 1804 m. The measured difference in the gravitational potentials between the positions of the two quantum clocks was (182.0 ± 3.1)10²m²s^-2 at a relative measurement error of no more than 1.7%.     

Creation of light-emitting diode optical beacons for spacecraft

A successful development of the semiconductor light-emitting diode (LED) technology made it possible to design efficient high-power light emission sources with small weight-and-size parameters. The technical characteristics of these LEDs allow one to use them as optical beacons on spacecraft. The application of LED optical beacons jointly with other equipment is intended to improve navigation support of space programs.     

On deep electric conductivity of the lithosphere in the Tobol-Ishim interfluve (West Siberia)

On the basis of exploration magnetotelluric soundings (MTS) carried out by the Tyumen Geological Survey in 1980–1981 within the Tobol-Ishim interfluve, the top of the conductive horizon with the electric resistivity of dozens of Ω m is identified in the geoelectrical section at a depth of 75–80 km. Two segments of the locally elevated top of this horizon are revealed. One segment, where the depth of the top of the conductor is 60–65 km, corresponds to the region of the Kiselevskii fault-the main fault in this territory; another segment is associated with the edge zone of the Ishim branch of the Triassic rift system within the West Siberian Plate. Within this segment, the top of the conductive layer rises to a depth of 55-60 km. It is assumed that the Ishim geoelectrical anomaly, which projects into the geothermal anomaly and is coherent with the features of the deep geological structure of its display region, is conditioned by the element of the mantle-crustal magmatogene fluid paleosystem.     

Improvements of drilling fluid processing for cable-suspended electromechanical drills

Deep ice drilling in Polar Regions plays a key role in paleo-climate, microbiological and glaciological researches. For deep ice and subglacial coring the special purpose-built electromechanical cable-suspended drills with bottom-hole circulation are designed and explored. Used at present drilling fluid circulation systems are specified by very high fluid wastes during processing. Measurements in deep drilling projects in Antarctic and Greenland ice sheets showed that 25%-40% of the drilling fluid, pumped into the hole, is retrieved to the surface with cable and drill, and up to 45% of retrieved fluid goes to waste. This leads not only to increasing of the fluid consumption and cost of the project in general but also to severe contamination of air, surface and near-surface snow-firn layers at the drilling site. In order to reduce wastes and environmental impact, it is proposed to modify drilling fluid processing system by avoiding of evaporation and leakages of fluid as far as practicable. Drilling fluid is prepared and pumped into the hole according to predetermined program on semiautomatic mode, and volume and density of blended and pumped into the hole drilling fluid are measured continuously. Components of the drilling fluid are stored and mixed in the special closed containers equipped by pressure relief valves. Separation of drilling fluid from ice cuttings is carried out by two steps: firstly, fluid is separated with hydro extractor and then with thermal separator. To reduce the amount of removed drilling fluid with cable special squeezing collar is installed on the borehole mouth. All these arrangements are able to decrease drilling fluid wastes in many times.     

Optimization of ice cuttings transportation by cable-suspended core auger drills

Ice cores contain an abundance of information about the Earth＇s climate in the past, and recovered from shallow drilling down to 300-350 m give sufficient information for reconstructing of the last climatic changes and for monitoring of pollution from human being. Cable-suspended core auger drills use an armored cable with a winch to provide power to the down-hole motor system and to retrieve the down-hole unit. Because of their lightweight, convenient transportation and installation, high penetration rates and low power consumption, core auger drills are widely used for shallow drilling in ice. Nowadays at least 14 types of auger electromechani- cal drills were designed and tested in different foreign and national glaciological laboratories. However, auger options were usually determined by experience, and the main parameters （ helix angle of the fights and rotational speed） are varied in a wide range from drill to drill. If parameters of auger are not chosen properly, poorly en- gineered drills had troubles with low efficiency of cuttings transportation, jam of ice cuttings, repeated fragmen- tation, cutters icing and stop penetration, abnormal power consumption, high rotation torques, and so on. Thus, this paper presents the method of optimization of iee cuttings transportation of cable-suspended core auger drill on the base of the theory of rotary auger. As the result, the optimal helix angle was determined correspond- ing to the rotational speed from the transportation efficiency point of view.