Kola Superdeep Borehole — Attraction in Murmansk Oblast

IT HAS BEEN SAID THAT the human race knows more about certain distant galaxies than it does about the ground that lies beneath its very feet. In fact, while it took the famous Voyager 1 satellite 26 years to exit our Solar System (relaying measurements to Earth from 16.5 billion km away), it took about the same amount of time for humanity to penetrate a mere 12 km into the Earth’s surface.

While the U.S. and U.S.S.R. vied for space exploration supremacy during the Space Race, a different, less-publicized race took place between the two nation’s greatest drillers. In the late 1950s and early 1960s Americans and Soviets began planning separate efforts to drill as deep as possible into the Earth’s crust, the rocky shell that comprises the outer 30-50 km of the 6730 km distance to our planet’s core.

The American “Project Mohole,” stationed off the Pacific coast of Mexico, was cut short in 1966 due to lack of funding but set an important precedent for future off-shore drilling programs. The Soviets, thanks to the planning of the Interdepartmental Scientific Council for the Study of the Earth’s Interior and Superdeep Drilling, had greater success. From 1970 to 1994 their drill on the Kola Peninsula chipped slowly away to create a Earth-shattering record at the time: the deepest hole in the world.

In actuality, the Kola Superdeep Borehole consists of several holes branching from one central hole. The deepest hole is called “SG-3,” and though just nine inches in diameter, it extends down a staggering 7.5 miles. That’s roughly a third of the way through the Baltic continental crust.

To meet scientific objectives and provide a nearly continuous look at the crust’s profile, the Soviets even developed instruments to take direct physical measurements at the bottom of the borehole. The drilling apparatus thus allowed for greater measurement integrity since rock samples would deform under their incredible internal pressure when brought to the surface. Needless to say, the project produced enormous amounts of geological data, most of which elucidated how little we know about our planet.

The study of the Earth is often largely limited to surface observations and seismic studies, but the Kola borehole allowed a direct look at the structure of the crust and put geologist’s theories to the test. One of the most surprising findings was the absence of the transition from granite to basalt, which scientists had long expected to exist between three and six kilometers below the surface. Known to geologists as the “Conrad discontinuity,” this transition in rock type was reasoned to exist due to the results of seismic-reflection surveys.

Though the discontinuity has been detected beneath all of the continents, the drill at Kola never encountered the proposed layer of basalt. Instead, the granitic rock was found to extend beyond the twelve kilometer point. This led to scientists’ realization that the seismic-reflection results were due to a metamorphic change in the rock (i.e. from intense heat and pressure), and not a change in rock type as they had previously anticipated.

But the most intriguing discovery made by the Kola borehole researchers is undoubtedly the detection of biological activity in rocks more than two billion years old. The clearest evidence of life came in the form of microscopic fossils encased in organic compounds that remained surprisingly intact despite the extreme pressures and temperatures of the surrounding rock.

While data produced by the Kola drilling project continues to be analyzed, the drilling itself was forced to stop in the early 1990s when unexpectedly high temperatures were encountered. While the temperature gradient conformed to predictions down to a depth of about 10,000 feet, temperatures after this point increased at a higher rate until they reached 180 °C (or 356 °F) at the bottom of the hole. This was a drastic difference from the expected 100 °C (212 °F). Also unexpected was a decrease in rock density after the first 14,800 feet. Beyond this point the rock had greater porosity and...

Everyone who is fond of scientific tourism has to see it. Unfortunately little is left there. Well anyway that site still has its own atmosphere. Did you know that scientists there in mid 80ss discovered that the Earth crust at the deep of about 6 km is identical to the lunar regolite? That was identified there alond with insuring the theory of the Moon being produced by an impacty event in very distant past. And it's the deepest human made hole in Earth's crust with an exact depth of 12262m. The path and entrance to the site remains free as of August 7th 2024. I hightly recommend this place to those who are interested in geology and the...

Corría el año 1970, cuando los científicos de la Unión Soviética empezaron a perforar el Kola Superdeep Borehole (Pozo súper profundo de Kola) en Murmansk, Rusia. El objetivo era aprender más cosas sobre la corteza terrestre y vencer así a los científicos estadounidenses que abandonaron el Proyecto Mohole en 1966.

Pasados 24 años de excavaciones y después de una serie de ramificaciones en el agujero, la sección de mayor profundidad de la Kola Superdeep Borehole se detuvo en 1994 a 12,262 metros. Cuenta con solo 22 centímetros de diámetro en la parte inferior.

Continúa siendo el agujero de más profundidad del planeta y el proceso para perforarlo fue de lo más complicado. Eso sí, no es el agujero de mayor longitud, pues en mayo de 2008, un pozo de petróleo le arrebató el record, pero no es tan subterráneo.

¿Qué encontraron los científicos?

Lo primero, mucha agua ahí abajo, aunque estaba formada por oxígeno extraño y átomos de hidrógeno extraídos de minerales rocosos. Se encontraron también fósiles de plancton a la sorprendente profundidad de 6700 metros.

Era un lugar muy caliente, alcanzando temperaturas de más de 176 ° centígrados. A pesar de todo el esfuerzo y décadas de trabajo, este agujero sólo supuso el 0,2% del camino que hay hacia el centro de la Tierra.

Se detuvieron los trabajos en 1992. El motivo fue que se hizo imposible técnicamente, el profundizar más en la corteza pues la temperatura de unos 180ºC , hacían fluir continuamente una masa de fango e hidrógeno.

En 2005 el proyecto se canceló por no tener más fondos y desde 2008 está abandonado. Existe una leyenda urbana que dice que los ruidos que a veces se escuchaban de su interior eran lloros y gritos. Todo esto dio lugar a muchas leyendas.  Entre ellas se decía que el Pozo Superprofundo de Kola llegaba hasta el mismo infierno y que los sonidos eran los lamentos de aquellos que estaban pagando por su penitencia en el infierno. Algo...