What is the maximum depth that we can dig?
KOLA SUPERDEEP HOLE :-
INTRODUCTION :-
The Kola Superdeep Hole is the hole with maximum depth. It could be said as a threshold to the center of the Earth. However, the natural maximum depth is of the Mariana Trench that is about. The depth of this hole is about 40,230 ft. [12,262 meters].
The hole is the result of a scientific drilling project in of SOVIET UNION. The digging was to continue as low as possible. The main aim behind digging it was to reach the crust of the EARTH and to study such type of things.
The diameter of the borehole is about 23 centimetre. This hole is the deepest hole in the world, instead of the longest. It remains the longest borehole for two decades.
LOCATION :-
This SUPERDEEP HOLE is located at the ruins of an abandoned project site in Murmansk, Russia, not far from the Norwegian border.
The digging began on 24th MAY of the year 1970. The machine that was required to start the digging was URALMASH 4-E. The goal was that was set that it would dig up to 15000 meters [49000 ft.]
This hole broke all the previously recorded hole of maximum depth. It broke the record of the Bertha Rogers hole in Washita County, Oklahoma, the United States whose length was about 9,583 meters.
The most interesting fact, that the scientists discover that there is no transition of granite to basalt till the depth of 7 kilometers.
Microscopic Plankton found at the depth of 6km. The rock found below the surface is fractured and is saturated with water. Another unexpected thing that they observe was a large quantity of Hydrogen gas
In the year 1983, the drill reached a depth of 12000 meters and then stopped for approximately a year to do study and research on them.
SOURCE: WIKIPEDIABRIEF:-
Name : KOLA SUPERDEEP HOLE
LOCATION: RUSSIA
TYPE: SCIENTIFIC BOREHOLE
GREATEST DEPTH: 12,262 METERS
INITIATED: 1965
ACTIVE : 1970-1983, 1984, 1985-1992
Why drilling stopped ?
After the study and research of numerous scientists, the digging began on SEPTEMBER 27, of the year 1984. Merely they have dug 66 meters, that is a total of 12,066 meters, their problems began. The drill string that is responsible for transmitting fluid, and torque to the drill bit, got twisted off [ height was 5000 meter] and remain in the hole.
Later on, drilling was restarted with a depth of 7,000 meters. This time they reached about 12,262 meters by the year 1989. An estimate was that it would reach 13,500 meters [ 44,300 ft.] by the end of 1990. And the whole task that is 15,000 meter[ 49000 ft.] would be completed by the upcoming year 1990. As the drilling machine reaching towards the Earth's crust, the temperature was also increasing.
Unknown to the temperature and depth of that location, they were digging. Soon they met the unexpected temperature of 180-degree centigrade (356 °F) instead of the expected 100 °C (212 °F). Soon they realized that drilling deeper was deemed unfeasible. The rock found at this much depth starts behaving like plastic due to its high porosity, decreasing density, and unexpected temperature.
By now the drilling was impossible below it. So, regretful they have to terminate the borehole in the year 1992 and this was officially discovered in 1995. In the year 2008, the Russian info centre announced that the Kola Superdeep Hole was to be destroyed. But, the site is still opened for the curiosity of visitor and they reported that the borehole is destroyed partially.
SIMILAR PROJECTS :-
PROJECT MANHOLE
The united states had commenced a similar project in the year 1957, launched project Manhole whose purpose was to link the shallow crust under the pacific ocean off of Mexico. But soon this project was abandoned within 4 years [1961] due to a lack of the fund.
KTB SUPERDEEP HOLE
The KTB superdeep hole at Windischeschenbach in Northern Bavaria begun in 1987, whose depth was 9,101 meters [29,859 ft.]. But its temperature reaches more than 260 °C (500 °F).
