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Near-vertical incidence reflection seismic data acquired in the Tagil Volcanic Arc (Middle Urals) show the upper crust to be highly reflective. Two intersecting seismic lines located near the ongoing ∼5400 m deep SG4 borehole show that the main reflectivity strikes approximately N-S and dips ∼35°–55° to the east. Prominent reflections intercept the borehole at ∼1000, ∼1500, 2800–2900, ∼3400, and between ∼4000 and 5400 m, which correspond to intervals of low velocity/low density/low resistivity. The surface projections of these reflections lie parallel to the strike of magnetic anomaly trends. Multioffset vertical seismic profile (VSP) data acquired in the SG4 borehole show a seismic response dominated by P to S reflected converted waves from the moderately east dipping reflectivity and from a set of very steep east dipping reflectors not imaged by the surface data. Modeling of the VSP data constrains the depth at which reflectors intercept the borehole and suggests that the P to S conversions are best explained by low-velocity porous intervals rather than higher-velocity mafic material. The most prominent east dipping reflection on the surface seismic data is only imaged on VSP shots that sample the crust closer to the E-W seismic line. This discrepancy between the VSP and the surface seismic data is attributed to rapid lateral changes in the physical properties of the reflector. Surface and borehole data suggest that the low-velocity/low-density/low-resistivity intervals are the most important source of reflectivity in the SG4 borehole area, although lithological contrasts may also play a role. Drill cores from the these zones contain hydrothermal alteration minerals indicating interaction with fluids. Tectonic criteria suggest that they might represent imbricated fracture zones often bounding different lithologies and/or intrusions. Some of them might also represent high-porosity lava flows or pyroclastic units, common in island arc environments.

Strip mining of coal in conditions of high water inflow is carried out using a non-conveying self-propelled excavator-dragline, or by a hydraulic dredger with a submersible pump and cutting head. In such conditions lack of visual control is a problem for the operator who is unable to see the coal surface and the thickness of the rock, leading to waste and low productivity. The development of a method for utilising sonar to overcome this is described, along with the on-board techniques for acoustic location and computer processing of the signals and images, and the characterisation of the computer software. A graphical image of a "dry coal face" is built up which allows the operator to define the coal-rock boundary., Strip mining of coal in conditions of high water inflow is carried out using a non-conveying self-propelled excavator-dragline, or by a hydraulic dredger with a submersible pump and cutting head. In such conditions lack of visual control is a problem for the operator who is unable to see the coal surface and the thickness of the rock, leading to waste and low productivity. The development of a method for utilising sonar to overcome this is described, along with the on-board techniques for acoustic location and computer processing of the signals and images, and the characterisation of the computer software. A graphical image of a "dry coal face" is built up which allows the operator to define the coal-rock boundary.

The upper crust in the Middle Urals is known to be highly reflective. However, it is not clear whether the observed reflections originate from lithological boundaries or from fault zones. The SG4 borehole located in the Tagil Synform of the Middle Urals, drilled to 5354 m as of August 1995, presents one opportunity to study the source of this reflectivity. The hole has penetrated several different lithologies as well as numerous tectonic or fracture zones. The upper 5070 m consist of island arc rocks which have presumably been thrust on top of basalts. To allow correlations between available surface seismic studies and the borehole observations vertical and offset seismic profile data were acquired in the borehole over the interval 520 m to 3940 m. Two shot points were used, a near offset one at 135 m from the wellhead and a far offset one at 1845 m from the wellhead. After processing, the borehole seismic data show numerous reflecting horizons. Many reflections correlate with major fracture zones, while others have no clear correlation with fracture zones nor lithological contrasts. The interval between approximately 4450 m and 5100 m, which is imaged below the bottom of the survey, shows a layered reflective pattern that correlates with the lower part of a flysch unit which ends at 5070 m. The basalts below appear to be relatively transparent. A prominent east-dipping reflector on a W-E CDP line about 700 m north of the wellhead is not clearly imaged on the borehole seismic. However, in a pilot hole which deviates a few hundred metres in the northerly direction from the main hole, a marked low-velocity zone is observed at the corresponding depth for this reflector, indicating its source to be from a fault zone. That the fault zone is not clearly observed on the borehole seismic data is attributed to 3D effects.

The Baikal Drilling Project (BDP) is a multinational effort to investigate the paleoclimatic history and tectonic evolution of the Baikal sedimentary basin during the Late Neogene. In March 1993 the Baikal drilling system was successfuly deployed from a barge frozen into position over a topographic high, termed the Buguldeika saddle, in the southern basin of Lake Baikal. The BDP-93 scientific team, made up of Russian, American and Japanese scientists, successfully recovered the first long (>100 m) hydraulic piston cores from two holes in 354 m of water. High quality cores of 98 m (Hole 1) and 102 m (Hole 2), representing sedimentation over the last 500,000 years, were collected in 78 mm diameter plastic liners with an average recovery of 72% and 90%, respectively. Magnetic susceptibility logging reveals an excellent hole-to-hole correlation. In this report the scientific team describes the preliminary analytical results from BDP-93 hole 1 cores. Radiocarbon dating by accelerator mass spectrometry provides an accurate chronology for the upper portion of Hole 1. Detailed lithologic characteristics, rock magnetic properties and inorganic element distributions show a significant change to the depositional environment occuring at 50 m subbottom depth, approximately 250,000 BP. This change may be due to uplift and rotation of the horst block in the Buguldeika saddle. The sedimentary section above 50 m is pelitic with varve-like laminae, whereas the section below 50 m contains a high proportion of sand and gravel horizons often organized into turbidite sequences. Accordingly, high resolution seismic records reveal a change in sonic velocity at this depth. It is inferred that sedimentation prior to 250 ka BP was from the west via the Buguldeika river system. After 250 ka BP the Buguldeika saddle reflects an increase in hemipelagic sediments admixed with fine-grained material from the Selenga River drainage basin, east of Lake Baikal. Variations in the spore-pollen assemblag

The performance of belt conveyors and the service life of belts and mechanical elements can be improved if the belt speed movement is automatically adjusted so that the unit load over the conveyor length is constant and close to the rated load under a random input of freight traffic. Such an adjustment is possible using a controllable thyristor electric drive with an induction squirrel cage motor. The results of the simulation of speed control of the conveyor belt are given. The research has identified an opportunity for the reduction of transport power intensity by 20-25%. The results of the analytical study have been used to develop a pilot system at an open cast coal mine in Eastern Siberia., The performance of belt conveyors and the service life of belts and mechanical elements can be improved if the belt speed movement is automatically adjusted so that the unit load over the conveyor length is constant and close to the rated load under a random input of freight traffic. Such an adjustment is possible using a controllable thyristor electric drive with an induction squirrel cage motor. The results of the simulation of speed control of the conveyor belt are given. The research has identified an opportunity for the reduction of transport power intensity by 20-25%. The results of the analytical study have been used to develop a pilot system at an open cast coal mine in Eastern Siberia.

A method is described of obtaining antifrothing, aqueous polyorganosiloxane emulsions by means of mixing polyorgraosiloxane with 'Aerosil' under heating, followed by cooling and the addition of an aqueous solution of an emulsifier under mixing. In order to increase the antifrothing effectiveness of the emulsions which are resistant to storage and heating, the emulsion is condensed by evaporation at a temperature of 85-120 degrees centigrade under reduced pressure. (Author), Edited trans. of Patent (USSR) 246 850 2p, 1969, by M. Olaechea.

The invention involves an aircraft propeller which has longitudinal slots through the blades. Stall flutter is prevented by making wedge-shaped slots in the tip sections of the blades, e.g. to z=0.87, and filling them with some elastic material such as rubber. (Author), Edited trans. of Patent (USSR) 201 096 p1-2, 1 Jun 64, by E. Harter.

The object of the invention is a method of obtaining heat-resistant materials on the basis of a union of polymers with metallic fillers. For the purpose of obtaining materials with improved heat resistance and mechanical strength, different dispersion metals as active or activated fillers are united with polycondensation or polymerization high-molecular compounds by the method of mechanochemical mixing in the process of vibration grinding or in special mixing machines with subsequent rolling. (Author), Unedited rough draft trans. of Russian Patent 136 556, pub. 7 Jul 60, appl. no. 673003/23.