The Greenland glacial board. Deep drilling

In total in Greenland it is drilled six deep wells, the first - around former military base Camp Century in northern part of island. Several years ago have been declassified and became property of wide sociability of a detail of the curious project. In the end of 50 years the Pentagon has developed the grandiose program of building of a net of multikilometer tunnels in a strata of a glacial integument of Greenland on which trains with ballistic missiles should ply. Thus, their discovery and destruction for the countries - participants of the Warsaw Contract was an unreal problem.

In 1959 the base which all premises were under a snow mantle has been constructed. The garrison (250 military men) Here took places, and with the electric power the base was provided with a small atomic reactor.

In same time the American experts Hansen and Ueda from US Army Cold Regions Research and Engineering Laboratory - CRREL have suggested to use for the first time a thermal electric drill for drilling of wells in ice. This device had a ring heater power of 3 kw. Melt-water was sucked away on tubes in a water-producing tank by means of the vacuum pompe. A chisel shell in length of 10.5 m and mass about 400 kg drained off in well on a load a bearing cable by means of a winch with a hydraulic drive and towers in height of 31 m.

In 1960-1961 around base Camp Century this shell drills "dry" well by depth of 186 m, and then, after some improvements of the thermal electric drill, two more: depth of 238 m (1962) and 264 m (1963).

As because of constant glacier movement the well at drilling is narrowed, in parallel in the same laboratory the device with its which help was developed it is possible to fill in with "low-temperature" flushing fluid (an admixture of diesel fuel DF-A with trichlorethylene). Such shell was similar on developed earlier, but instead of the vacuum pompe in a water-producing tank the hydraulic pompe took places.

In 1964 by means of the new device have deepened well with 264 to 535 m. However up to the end to fulfil technology it was not possible: melt-water particulate remained in well and turned in needle ice the figurative mass, stirring to drilling. The augmentation of power electroheating of elements did not help also - they quickly fused. Therefore subsequently efforts have been concentrated to mining not electrothermal, but electromechanical devices.

In 1965 it was possible to modernise an electric drill of construction Arutyunov. The basic feature of drilling this shell the in length of 26.5 m and mass 1100 kg consisted that solved slime formed in well in circulating solution of ethylene glycol - the solution of equilibrium concentration which is not freezing at temperature of environing ice was formed. Therefore before each flight the shell tank was filled with the concentrated solution of this material. In the summer 1965 and 1966 on the basis of Camp Century the well, driven earlier thermobrown to a mark of 535 m, has been deepened by a new shell to 1391 m.

In the early eighties in frameworks (Greenland Ice Sheet Program - GISP-1), organised by National scientific fund of the USA with participation of Denmark, France, Germany, Switzerland, at station "Дай-3" has been drilled well by depth of 2037.6 m. By means of original electromechanical shell ISTUK (in transfer with Danish decoding of this abbreviation is read: for deep drilling), the Copenhagen developed at University, it was possible to drive a shell through all glacial strata. The mass of this device has compounded about 180 kg, length - 11.5 m; diameter of drilling - 129.6 mm.

Thus slime together with flushing fluid was sucked on the rectangular tubes fixed on an outside surface of a core tube, in an intrinsic lumen of the piston pompes which are carrying out simultaneously a role of sludge-catchment basins. Have been solved here and power supply problems: the storage module placed in an airproof compartment of a shell, consisted from 55 nickel-kadmievyh of elements and worked smoothly. That operation of all systems and shell units was put in action was new also and was monitored by means of the computer.

Has been in the nineties successfully complete Greenland Ice Program - GRIP, organised by the European scientific fund with participation of Denmark, France, Germany, Switzerland, Belgium, the Great Britain, Iceland and Italy, and also project GISP-2. As drilling points were on a dome of a glacial board - the Summit - in 30 km from each other, around the maximum power of a glacier, and operation on them has begun almost simultaneously, to a certain extent it became competition between scientists of Old and New Light.

As a result European GRIP of 3029 m, and "American" GISP-2 - in 1993 on depth of 3053 m. This well and for today - the deepest in Northern hemisphere ices have been finished in 1992 on depth, besides here the last of 1.55 m have been drilled on subglacial rocks.

In project GRIP the advanced construction of shell ISTUK, and in project GISP-2 - electromechanical shell PICO-5.2 ", developed in University of Alaska Fairbanks on the basis of designed earlier for drilling“ dry ”superficial wells has been used. The pumping knot and the sludge-catchment basin has been introduced into a shell compound with the perforated filter. For drilling on subglacial rocks the standard prospecting core panel was used. The terraneous chisel complex of shell РICO-5.2" is supplied by the original roundabout allowing easily and quickly to spend assemblage and dismantling of a chisel shell on separate knots and parts.

As flushing fluid used n-butilatsetat - the aether of acetic acid which is belonging to the class of high-toxic bonds (maximum permissible concentration of steams in air of working premises compounds only 200 mg/m3). Despite the ventilation organised in a chisel complex, the maximum concentration of steams n-butilatsetata more than in 5 times exceeds threshold value. According to the drill men working at sinking of well in oxygen breathing apparatuses, after the working day there were headaches, a nausea, dizziness. Besides, n-butilatsetat - aggressive solvent. After three-year operation in the well which has been filled in with this material, greasing of the polymerous reservation a load of a bearing cable has appeared blasted. Unique advantage which this chemical reagent possesses, - its relative cheapness.

Various researches of an ice core sample of the deep wells drilled at the Summit, have allowed to reconstruct a climate of the Earth for the last of hundred thousand years, to specify the causes of formation of ice boards, to date large volcanic eruptions, wilderness fires; to define anthropogenic pollution level etc.

However, despite the fulfilled procedure of isotope analysis of ice, results of researches of the core samples extracted from two wells at the Summit from depths more 300 m, is essential differ, in particular and for the warm season of history of the Earth, taking place about 120 thousand years ago. Exact reconstruction of climatic changes of that time is especially important, as them consider as possible analogue of modern lines.

For the purpose of reception more the trustworthy information about a climate of that season in 1996 has been begun North Greenland Ice Project - NGRIP Denmark and Germany became which basic executors. Among participants - Belgium, France, Iceland, Japan, Switzerland, Sweden and the USA. For drilling the polygon where, according to radar researches, ancient annual layers have the big power, than at the Summit is chosen.

For well sinking the Danish and French experts have prepared a new shell which in the constructive attitude represents synthesis of the previous electromechanical devices. The upper not rotating part - the drummer, the brace device and an electrocompartment - are borrowed from shell ISTUK.

Drilling has begun in 1996 In 1997 is intercepted because of failure. In 1998 the new well - in 25 m from a mouth of the first is gobed up. The fosse, the same dimensions, as previous, has been bridged by passes to an old drill site and a core sample storehouse.

In 1999 and 2000 the author of article took part in this project as the scientific employee and within several months was engaged in drilling, preparation of flushing fluid, liquidation of complications and failures, preservation of a chisel complex.