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Abstract: At present, in our country the main deep drilling rigs are rotary disk drilling rig, spindle-type drilling rig and full hydraulic motor head drive drilling rig, and most of foreign drilling rig equipment are full hydraulic motor head drive drilling rigs. These rigs have many disadvantages; they cannot meet the demand of deep drilling. As the major breakthroughs were made in the development of high power permanent magnet frequency conversion motor, it is possible to develop the permanent-magnet motor direct drive top-driving drilling rig, so the efficiency of drilling can be improved. In this paper, the difficulties of deep drilling and existing problems of deep drilling rigs are analyzed, and direct drive permanent magnet motor top-driving drilling rig and its parameters and characteristics are introduced. The development of deep borehole permanent-magnet motor direct drive top-driving drilling rig accords with the requirements of drilling technology development and innovation concept, it is the development direction of deep core drill's renewal, will promote the development of geo-drilling technology. [Copyright &y& Elsevier]

This paper focused on optimizing deep drilling parameters based on Taguchi method for minimizing surface roughness. The experiments were conducted on CNC lathe machine using solid carbide cutting tool on material AISI 321 austenitic stainless steel. Four cutting parameters such as cutting fluid, speed, feed and hole-depth, each at three levels except the cutting fluid at two levels were considered. Taguchi L 18 orthogonal array was used as design of experiment. The signal-to-noise (S/N) ratio and the analysis of variance (ANOVA) was carried out to determine which machining parameter significantly affects the surface roughness and also the percentage contribution of individual parameters. Confirmation test was conducted to ensure validity of the test result. The results revealed that the combination of factors and their levels A 2 B 3 C 2 D 1 i.e. the machining done in the presence of cutting fluid, at a speed of 500 r.p.m. with a feed of 0.04 mm/s and hole-depth of 25 mm yielded the optimum i.e. minimum surface roughness. Further, the results of ANOVA indicated that all four cutting parameters significantly affected the surface roughness with maximum contribution from speed (27.02%), followed by cutting fluid (25.10%), feed (22.99%), and hole-depth (14.29%). It is also observed that the surface finish for deep drilling process can be improved effectively through this approach. [ABSTRACT FROM AUTHOR]

Abstract: Based on results of deep drilling and the CDP-2D seismic profiling, the relations between the Early and Middle Cambrian carbonaceous rocks and the underlying, overlying, and synchronously formed deposits in the Siberian Platform are analyzed, and the lithologo-paleo- geographic, paleotectonic, and tectonic conditions of their formation are considered. It is shown that these carbonaceous rocks are intimately related to the Cambrian organogenic structures, up to their mutual transitions. [Copyright &y& Elsevier]

We present a new 52 m composite record (COL17c) composed of five sedimentary sequences retrieved from the Colônia basin (Southeastern Brazil). The COL17c record is composed of two main sub-units deposited under different regimes: a peatland above ~14 m and lacustrine sediments below. Sedimentary description and core scanning (MSCL and XRF) are first used to align individual cores in order to produce a nearly continuous composite record. We then established an original chronological framework based on radiocarbon, paleomagnetic, optically stimulated luminescence (OSL), post-infrared infrared stimulated luminescence at elevated temperature (pIRIR 290°C) and authigenic 10Be/9Be dating. We describe the protocols used for each technique and discuss the positive and negative results, as well as their implications for proxy interpretation. In spite of negative results of some techniques, mainly due to the absence of adequate sample material, the multi-proxy approach used is essential to maximize the chances of obtaining a satisfactory age model for this unique continental sedimentary sequence. All valid chronological proxies, comprising three AMS 14C ages, one pIRIR 290°C age, two paleomagnetic constraints and eight authigenic 10Be/9Be datum, are integrated within a Bayesian age-depth modeling to produce a 1.5 ± 0.1 Ma chronology for the whole COL17c sequence. This age model represents the first long-term chronological estimate of sediments deposition in the Colônia basin. The record allows to refine the age of the Colônia basin formation between 5.3 and 11.2 Ma, much older than previously estimated from short sedimentary cores. • A 52 m composite record from the Colônia basin is built from 5 sedimentary cores • The 1.5 ± 0.1 Ma age-depth model is based on independent geochronometers • Paleomagnetic and authigenic 10Be/9Be dating used in a Bayesian age-depth modeling • XRF scanning of COL17c sediments reveal large-scale paleoenvironmental variations • The age of the Colônia basin formation is revised between 5.3 and 11.2 Ma [ABSTRACT FROM AUTHOR]