The main minerals of the continent of Antarctica. Antarctica - the last frontier before conquering the moon and Mars
Antarctica is the coldest and most mysterious place on the planet. The continent is completely covered with a crust of ice, so data on minerals in the territory of this icy desert are very scarce. It is known that under the thickness of snow and ice there are deposits of coal, iron ore, precious metals, granite, crystal, nickel and titanium.
Such little knowledge about the geology of the continent is explained by the difficulty of conducting research due to low temperatures and too thick ice shell.
Features of the relief of Antarctica
99.7% of the mainland's surface is covered with ice, the average thickness of which is 1720 m. Under the ice of Antarctica, the relief is heterogeneous: in the eastern part of the mainland, 9 regions are distinguished, differing in the period of formation and their structure. The Eastern Plain has drops from 300 meters below sea level to 300 m above sea level, the Transantarctic Mountains run through the entire continent and reach 4.5 km in height, the slightly smaller mountain range of Queen Maud Land stretches 1500 km along and rises up to 3000 m, the plain Schmidt took a height of -2400 to +500 m, the Western Plain is located approximately at sea level, the arcuate mountain range of Gamburtsev and Vernadsky stretched for 2500 km, the Eastern Plateau adjoins the Schmidt Plain (+1500 m), the Prince Charles mountain system is located in the MGY valley and the ridge of Enderby Land reaches a height of 3000 m.
In the western part there are three mountain systems (Ellsworth Massif, Cape Amundsen Mountains, Antarctic Peninsula Ridge) and Baird Plain, located at 2555 meters below sea level.
Theoretically, regions on the periphery of the continent can be considered the most promising for mining - the interior of Antarctica has been little studied, and any research work is complicated by remoteness from the coast.
Types of minerals
The first data on the deposits of minerals, ores and metals appeared at the beginning of the last century - then it was possible to discover layers of coal. At the moment, there are more than two hundred points on the territory of Antarctica, only two are for certain identified as deposits - these are deposits of iron ore and coal. Industrial production from both deposits in the conditions of Antarctica is considered absolutely unprofitable, although coal and ore are in demand materials for extraction in all countries.
Other minerals and ores found in Antarctica include copper, titanium, nickel, zirconium, chromium, and cobalt. Precious metals are represented by gold and silver on the West Coast of the Antarctic Peninsula. On the shelf of the Ross Sea, gas shows were found in boreholes, which indicates possible deposits of natural gas, but their volume has not been established.
Resources and deposits
(Lake Vostok at a depth of more than 3.5 km under the Antarctic ice)
It is known for certain that the coal deposit in the Commonwealth Sea includes more than 70 seams and can reach several billion tons. In addition, seams of coal, albeit in smaller quantities, are present in the Transantarctic Mountains.
Despite the possibility of finding other deposits, geological studies of Antarctica are developing only in the direction of determining the presence of minerals in certain zones.
More thorough reconnaissance missions or industrial mining in the South Pole is unprofitable, requires huge material costs, human resources and legislative litigation, because. The legal status of Antarctica is determined by the "Antarctic Treaty" and provides for the use of the region only in peaceful and scientific research, without the right to the territorial affiliation of any of the countries. Thus, any extraction of minerals is possible only under the condition of international cooperation and large subsidies aimed at research work, and not at making a profit from the sale of found minerals.
Scientists from NASA predict the imminent formation of a new giant iceberg that will separate from the Brunt Ice Shelf. Its area will be about one thousand seven hundred square kilometers, which is comparable to the area of a metropolis. Two large cracks, one of which is growing by about four kilometers a year, continue to approach each other and a giant iceberg may break away from the glacier in the very near future.
British scientists from the University of Edinburgh have discovered about a hundred new volcanoes located in the west of Antarctica under a huge layer of ice. The height of the largest of them is about four thousand meters. This volcanic region is larger than the rift system in East Africa, and its activity could have serious consequences as it shifts the ice sheets of western Antarctica.
Specialists of the enterprise "Polar Marine Exploration Expedition" summed up the results of the field season they spent in the Prydz Bay of the Commonwealth Sea in Antarctica. The research was carried out under a government contract, as part of the 62nd Russian Antarctic Expedition. Geologists carried out a comprehensive seismic survey covering an area of more than three thousand one hundred linear kilometers, carried out gravimetric and geomagnetic measurements. The received data is currently undergoing final processing.
Observing the Antarctic Larsen glacier, scientists have come to the conclusion that in the near future a giant iceberg will break off from it, the area of \u200b\u200bwhich will be about five thousand square kilometers. The destruction of the last part of this ice shelf (Larsen C) may be, according to researchers, the first step towards its final disappearance.
The specialists of the Mining University started the research season in Antarctica and started drilling at the Vostok station to continue studying the relic subglacial lake. In the next few months, scientists will conduct core drilling and test new technical means.
Ural scientists returned from the Antarctic expedition, which ended very successfully - scientists discovered three hundred fragments of meteorites.
The researchers found that 40 percent of the ice is more than three meters thick, and 90 percent of the ice is more than one meter thick.
Australian scientists have discovered rocks in the east of Antarctica that are similar in composition to kimberlites. The samples taken are about 120 million years old.
A group of American geologists, having studied seismographic observations, came to the conclusion that the cause of the melting of Arctic ice may be the activity of young subglacial volcanoes located at a kilometer depth in the area of Mary Byrd Land
Scientists who discovered three objects in Antarctica that resemble pyramids believe that they are of artificial origin
General information
The continent of Antarctica lies entirely in the southern polar region, which is called Antarctica (translated from Greek, anti means against), that is, lying opposite the northern polar region of the globe, the Arctic. The conditional boundary of Antarctica is considered to be 48-60C Yu.Sh.
The area of Antarctica is 13,975 thousand square meters. km (together with ice shelves and islands and ice domes attached to the mainland). The area of Antarctica with a continental shelf is 16,355 thousand square meters. km. The long and narrow Antarctic Peninsula stretches towards South America, the northern end of which, Cape Sifre, reaches 63 13 S.S. (the northernmost point of Antarctica). The center of the mainland, which is called the "pole of relative inaccessibility", is located approximately at 84 S.Sh. and 64 E, 660 km from the South Pole. The coastline, over 30,000 km long, consists of glacial cliffs up to several tens of meters high.
Most of the mainland is formed by the Precambrian Antarctic platform, which is framed on the coast of the Pacific sector by Mesozoic folded structures (coastal areas of the Bellingshausen and Amundsen seas, as well as the Antarctic Peninsula). The Antarctic platform is structurally heterogeneous and of different ages in different parts. Most of it on the coasts of East Antarctica is the Upper Archean crystalline basement, composed of various gneisses, schists, migmatites, shadow granites and other rocks with a total thickness of 15-20 km.
On the outskirts of the platform, within the Transantarctic Mountains and Mary Berle Land, there is the ancient Caledonian plate. Its foundation is formed by a two-tier folded stratum: at the bottom, a pre-Riphean gneiss-granite complex, at the top, Riphean and Cambrian volcanogenic deposits up to 10 km thick.
The platform cover is represented by various sandstones, siltstones, and shales up to 3 km thick.
The foldbelt of Antarctica is formed by three structural tiers. In the junction of the platform and the folded belt of Antarctica, Early Mesozoic folded structures have been identified.
In Antarctica, deposits of coal, iron ores have been discovered, signs of deposits of mica, graphite, rock crystal, gold, uranium, copper, and silver have been established. The small number of mineral deposits is explained by the poor geological knowledge of the mainland and its thick ice sheet. The prospects for the Antarctic subsoil are very great. This conclusion is based on the similarity of the geological structure of the Antarctic platform with the Gondwanan platforms of other South continents. hemisphere, as well as on the commonality of the folded belt of Antarctica with the mountain structures of the Andes.
The world economy's demand for mineral resources will only grow. Against this background, Invest-Foresight experts say, the problem of developing the resources of Antarctica may come to full height. Although it is protected from the development of mineral resources by numerous conventions and treaties, this may not save the coldest continent on the planet.
© Stanislav Beloglazov / Photobank Lori
It is estimated that developed countries consume approximately 70 percent of all the world's minerals, although they possess only 40 percent of their reserves. But in the coming decades, the growth in the consumption of these resources will not be at the expense of developed countries, but at the expense of developing countries. And they are quite capable of paying attention to the Antarctic region.
Expert of the Union of Oil and Gas Producers Rustam Tankaev believes that at the moment the extraction of any minerals in Antarctica is not economically viable and is unlikely to ever become so.
“In this respect, even the Moon, in my opinion, is more promising in terms of the development and extraction of mineral resources. Of course, we can say that technologies are changing, but space technologies are developing even faster than Antarctic ones,” the expert emphasizes. — There were attempts to drill wells to open ancient cavities with water in the hope of finding ancient microorganisms. There was no such thing as searching for mineral resources at the same time.”
The first information that the ice continent is rich in minerals appeared at the beginning of the 20th century. Then the researchers discovered layers of coal. And today, for example, it is known that in one of the water areas surrounding Antarctica - in the Commonwealth Sea - a coal deposit includes more than 70 seams and can reach several billion tons. There are thinner deposits in the Transantarctic Mountains.
In addition to coal, Antarctica has iron ore and rare earth and precious metals such as gold, silver, copper, titanium, nickel, zirconium, chromium and cobalt.
The development of minerals, if it ever starts, can be very dangerous for the ecology of the region, says a professor at the Faculty of Geography of Moscow State University Yuri Mazurov. There is no unambiguous vision of the consequences of such abstract significant risks, he reminds.
“On the surface of Antarctica, we see a dense thickness of ice up to 4 kilometers, and we still have little idea what is under it. In particular, we know, for example, that there is Lake Vostok there, and we understand that organisms from there can have the most amazing nature, including those associated with alternative ideas about the origin and development of life on the planet. And if so, it requires an incredibly responsible attitude to economic activities in the vicinity of the lake, ”he warns.
Of course, the expert continues, every investor who decides to develop or search for mineral resources on the ice continent will try to get various recommendations. But in general, Mazurov recalls, there is a principle in one of the UN documents, which is called "On the historical responsibility of states for the preservation of the nature of the Earth."
“It says explicitly, “economic activity, the economic result of which exceeds the environmental damage or is unpredictable, cannot be allowed.” The situation in Antarctica is just the second. Until now, there is not a single organization that could conduct an examination of the project with a deep immersion in the nature of Antarctica. I think this is just the case when you need to follow the letter and not guess about the possible outcome, ”the expert warns.
And he adds that the probability of some point, very accurate developments can be considered acceptable.
By the way, the documents themselves, which protect the mineral resources of the ice continent from development and development, are strong only at first glance. Yes, on the one hand, the Antarctic Treaty, which was signed on December 1, 1959 in the United States, is open-ended. But on the other hand, the Convention on the Management of the Development of Mineral Resources of Antarctica, which was adopted on June 2, 1988 by a meeting of 33 states, is still in limbo.
The main reason is that in Antarctica, under the main treaty, "any activity related to mineral resources is prohibited, with the exception of scientific research." In theory, it follows from this that the 1988 Antarctic Minerals Convention cannot and will not apply while this prohibition is in effect. But another document, the Environmental Protection Protocol, says that after 50 years from the date of its entry into force, a conference may be convened to consider how it operates. The Protocol was approved on October 4, 1991 and is valid until 2048. It can, of course, be canceled, but only if the participating countries renounce it, and then adopt and ratify a special convention on the regulation of the extraction of mineral resources in Antarctica. Theoretically, the development of minerals can be carried out with the help of so-called international consortia, the rights of participants in which are equal. Perhaps other options will emerge in the coming decades.
“There are much more promising regions on Earth for mining in the future. In Russia, for example, there is a huge territory of the Arctic lands and the shelf, the reserves of minerals are huge, and the conditions for their development are much better compared to Antarctica,” Rustam Tankaev is sure.
Of course, it is possible that by the end of the 21st century, the issues of developing the mineral wealth of Antarctica will still have to be transferred from the theoretical to the practical plane. The whole question is how to do it.
It is important to understand one thing - the ice continent in any situation should remain an arena of interaction, not discord. As, in fact, it has been customary since its discovery in the distant 19th century.
ANTARCTICA is the southern polar continent, occupying the central part of the southern polar region of Antarctica. Almost entirely located within the Antarctic Circle.
Description of Antarctica
General information. The area of Antarctica with ice shelves is 13,975 thousand km2, the area of the continent is 16,355 thousand km2. The average height is 2040 m, the highest is 5140 m (Vinson Massif). The surface of the ice sheet of Antarctica, which covers almost the entire continent, exceeds 3000 m in the central part, forming the largest plateau on Earth, 5-6 times larger than Tibet. The Transantarctic mountain system, crossing the entire continent from Victoria Land to the eastern coast of Cape Weddell, divides Antarctica into two parts - Eastern and Western, differing in geological structure and relief.
History of Antarctic exploration
Antarctica as an icy continent was discovered on January 28, 1820, by a Russian round-the-world naval expedition led by F. F. Bellingshausen and M. P. Lazarev. Later, as a result of the work of expeditions from various countries ( , ), the contours of the shores of the icy continent began to gradually emerge. The first evidence of the existence of an ancient continental crystalline basement under the ice sheet of Antarctica appeared after the work in the Antarctic waters of the English expedition on board the Challenger ship (1874). In 1894, the English geologist J. Murray published a map showing the Antarctic continent as a single landmass for the first time. Ideas about the nature of Antarctica were formed mainly as a result of summarizing the materials of sea expeditions and studies carried out during campaigns and at scientific stations on the coast and in the interior of the mainland. The first scientific station at which year-round observations were made was set up at the beginning of 1899 by an English expedition led by the Norwegian explorer K. Borchgrevink at Cape Adair (the northern coast of Victoria Land).
The first scientific trips into the depths of Antarctica along the Pocca Ice Shelf and the high-mountain ice plateau of Victoria Land were made by the British expedition of R. Scott (1901-03). The English expedition of E. Shackleton (1907-09) traveled up to 88 ° 23 "south latitude from the Pocca Peninsula towards the South Pole. For the first time, R. Amundsen reached the South Geographic Pole on December 14, 1911, and Scott's English expedition on January 17, 1912. Great contribution introduced into the study of Antarctica by the Anglo-Australian-New Zealand expeditions of D. Mawson (1911-14 and 1929-1931), as well as by the American expeditions of R. Baird (1928-30, 1933-35, 1939-41, 1946-47). — In December 1935, the American expedition of L. Ellsworth crossed the mainland from the Antarctic Peninsula to the Pocca Sea for the first time by plane. Only in the mid-1940s were long-operating stations organized on the Antarctic Peninsula.
Extensive studies of the icy continent using modern vehicles and scientific equipment unfolded during the International Geophysical Year (IGY; July 1, 1957 - December 31, 1958). 11 states took part in these studies, incl. , USA, UK and France. The number of scientific stations has sharply increased. Soviet polar explorers created the main base - the Mirny Observatory on the coast of Cape Davis, opened the first inland station Pionerskaya in the depths of East Antarctica (at a distance of 375 km from the coast), then 4 more inland stations in the central regions of the mainland. In the depths of Antarctica, expeditions from the USA, Great Britain and France created their stations. The total number of stations in Antarctica reached 50. At the end of 1957, Soviet researchers made a trip to the region of the geomagnetic pole, where the Vostok station was established; at the end of 1958 the pole of relative inaccessibility was reached. In the summer season of 1957-58, an Anglo-New Zealand expedition led by W. Fuchs and E. Hillary crossed the Antarctic continent for the first time from the coast of the Weddell Sea across the South Pole to the Pocca Sea.
The largest geological and geological-geophysical studies in Antarctica are carried out by expeditions of the USA and the CCCP. American geologists work mainly in West Antarctica, as well as on Victoria Land and the Transantarctic Mountains. Soviet expeditions covered with their research almost the entire coast of East Antarctica and a significant part of the adjacent mountainous regions, as well as the coast of the Weddell Sea and its mountainous framing. In addition, Soviet geologists participated in the work of US and British expeditions, conducting research on Mary Byrd Land, Ellsworth Land, the Antarctic Peninsula and the Transantarctic Mountains. In Antarctica there are about 30 scientific stations (1980), operating permanently or for a long period, and temporary expeditionary bases with replaceable personnel, which contain 11 states. The wintering staff at the stations is about 800 people, of which about 300 are members of the Soviet Antarctic expeditions. The largest permanent stations are Molodyozhnaya and Mirny (CCCP) and McMurdo (USA).
As a result of research using various geophysical methods, the main features of the nature of the icy continent have been elucidated. For the first time, information was obtained on the thickness of the ice sheet of Antarctica, its main morphometric characteristics were established, and an idea was given of the relief of the ice bed. Of the 28 million km of the volume of the mainland, located above sea level, only 3.7 million km 3, i.e. only about 13% falls on the "stone Antarctica". The remaining 87% (over 24 million km 3) is a powerful ice sheet, the thickness of which in some areas exceeds 4.5 km, and the average thickness is 1964 m.
Ice of Antarctica
The ice sheet of Antarctica consists of 5 large and a large number of small peripheries, terrestrial domes and covers. On an area of more than 1.5 million km 2 (about 11% of the territory of the entire continent), the ice cover is afloat in the form of ice shelves. Territories that are not covered with ice (mountain peaks, ridges, coastal oases) occupy a total of about 0.2-0.3% of the entire area of \u200b\u200bthe mainland. Information about the thickness of the earth's crust testifies to its continental character within the mainland, where the thickness of the crust is 30-40 km. The general isostatic balance of Antarctica is assumed - compensation for the load of the ice sheet by subsidence.
Relief of Antarctica
In the bedrock (subglacial) relief of East Antarctica, 9 large orographic units are distinguished: the Vostochnaya Plain with altitudes from +300 to -300 m, lying to the west of the Transantarctic Ridge, in the direction of Vostok station; the Schmidt plain, located south of the 70th parallel, between 90 and 120 ° east longitude (its heights range from -2400 to + 500 m); the Western Plain (in the southern part of Queen Maud Land), the surface of which is approximately at sea level; the Gamburtsev and Vernadsky mountains, stretching in an arc (about 2500 km long, up to 3400 meters above sea level) from the western tip of the Schmidt plain to the Riiser-Larsen peninsula; Eastern Plateau (height 1000-1500 m), adjacent from the southeast to the eastern end of the Schmidt Plain; the IGY valley with the Prince Charles mountain system; Transantarctic mountains, crossing the entire continent from the Weddell Sea to the Pocca Sea (altitude up to 4500 m); mountains of the Queen Maud Land with the highest height over 3000 m and a length of about 1500 km; the mountain system of Enderby Land, height 1500-3000 m. In West Antarctica, 4 main orographic units are distinguished: the ridge of the Antarctic Peninsula and Alexander I Land, height 3600 m; mountain ranges of the coast of cape Amundsen (3000 m); median massif with the Ellsworth mountains (maximum height 5140 m); Baird Plain with a minimum elevation of -2555 m.
Climate of Antarctica
The climate of Antarctica, especially its interior regions, is severe. The high altitude of the ice sheet surface, the exceptional transparency of the air, the predominance of clear weather, and the fact that the Earth is at perihelion in the middle of the Antarctic summer create favorable conditions for the influx of a huge amount of solar radiation in the summer months. The monthly values of total solar radiation in the central regions of the continent in summer are much greater than in any other region of the globe. However, due to the high albedo values of the snow surface (about 85%), even in December and January, most of the radiation is reflected into outer space, and the absorbed energy barely compensates for the heat loss in the long-wavelength range. Therefore, even at the height of summer, the air temperature in the central regions of Antarctica is negative, and in the region of the cold pole at Vostok station it does not exceed -13.6°C. On most of the coast in summer, the maximum air temperature is only slightly above 0°C. In winter, during the round-the-clock polar night, the air in the surface layer is greatly cooled and the temperature drops below -80 ° C. In August 1960, the minimum temperature on the surface of our planet -88.3 ° C was recorded at the Vostok station. In many parts of the coast, hurricane-force winds are frequent, which are accompanied by heavy snowstorms, especially in winter. The wind speed often reaches 40-50 m/s, sometimes even 60 m/s.
Geological structure of Antarctica
In the structure of Antarctica, there are (East Antarctic craton), the Late Precambrian-Early Paleozoic fold system of the Transantarctic Mountains and the Middle Paleozoic-Mesozoic West Antarctic fold system (see map).
In the interior of Antarctica are the least explored areas of the mainland. The most extensive depressions in the bedrock of Antarctica correspond to actively developing sedimentary basins. The most important elements of the continent's structure are numerous rift zones.
The Antarctic platform (an area of about 8 million km2) occupies mostly East Antarctica and the sector of West Antarctica between 0 and 35° west longitude. On the coast of East Antarctica, a predominantly Archean crystalline basement is developed, composed of folded metamorphic strata of granulite and amphibolite facies (enderbites, charnockites, granite gneisses, pyroxene-plagioclase schists, etc.). In the post-Archean time, these sequences are intruded, anorthosite-granosyenites, and. The basement is locally overlain by Proterozoic and Lower Paleozoic sedimentary-volcanogenic rocks, as well as Permian terrigenous deposits and Jurassic basalts. Proterozoic-Early Paleozoic folded strata (up to 6000-7000 m) occur in aulacogenes (Prince Charles Mountains, Shackleton Range, Denman Glacier area, etc.). The ancient cover is developed in the western part of Queen Maud Land, mainly on the Reacher Plateau. Here, on the Archean crystalline basement, platform Proterozoic sedimentary-volcanogenic strata (up to 2000 m) intruded by the main rocks lie subhorizontally. The Paleozoic complex of the cover is represented by Permian coal-bearing strata (clayey, with a total thickness of up to 1300 m), in some places overlain by tholeiite (up to 1500-2000 m thick) of the Middle Jurassic.
The Late Precambrian-Early Paleozoic folded system of the Transantarctic Mountains (Rosskaya) arose on the crust of the continental type. Its section has a distinct two-tiered structure: the folded Precambrian-Early Paleozoic basement is peneplanated and overlain by an undislocated Middle Paleozoic-Early Mesozoic platform cover. The folded basement includes protrusions of the reworked Dorosian (Lower Precambrian) basement and the Russian proper (Upper Precambrian–Lower Paleozoic) volcanosedimentary sequences. The Epiros (Bikon) cover (up to 4000 m) consists mainly of, in some places topped with Jurassic basalts. Among the intrusive formations in the basement, rocks of the composition of quartz diorites predominate, and with local development of quartz and granites; intrusive facies of the Jurassic break through both the basement and the cover, with the largest being localized along the surface of the structural.
The West Antarctic fold system frames the Pacific coast of the mainland from the Drake Passage in the east to the Pocca Sea in the west and represents the southern link of the Pacific mobile belt with a length of almost 4000 km. Its structure is determined by the abundance of protrusions of the metamorphic basement, intensively reworked into and partially bordered by Late Paleozoic and Early Mesozoic geosynclinal complexes, deformed near the boundary and; The late Mesozoic-Cenozoic structural stage is characterized by a weak dislocation of powerful sedimentary and volcanogenic formations that accumulated against the background of contrasting orogeny, and intrusive. The age and origin of the metamorphic basement of this zone have not been established. Late Paleozoic-Early Mesozoic includes thick (several thousand meters) intensely dislocated strata of predominantly shale-graywacke composition; in some areas there are rocks of the siliceous-volcanogenic formation. The Late Jurassic-Early Cretaceous orogenic complex of volcanogenic-terrigenous composition is widely developed. Outcrops of the Late Cretaceous-Paleogene molasse complex of rocks are noted along the eastern coast of the Antarctic Peninsula. Numerous intrusions of gabbro-granite composition, mainly of Cretaceous age.
Developing basins are "apophyses" of oceanic depressions in the body of the continent; their outlines are determined by collapse structures and, possibly, powerful sliding movements. In West Antarctica, the following stand out: the Pocca Sea basin with a thickness of 3000-4000 m; the basin of the Amundsen and Bellingshausen seas, the data on the deep structure of which are practically absent; the Weddell Sea basin, which has a deeply submerged heterogeneous basement and a cover thickness ranging from 2000 m to 10,000-15,000 m. In East Antarctica, the Victoria Land, Wilkes Land and Prydz Bay basins stand out. The thickness of the cover in the Prydz Bay basin is 10,000–12,000 m according to geophysical data; the remaining basins in East Antarctica are contoured according to geomorphological features.
Rift zones have been distinguished from a large number of Cenozoic grabens based on the specific features of the structure of the earth's crust. The rift zones of the Lambert Glacier, the Filchner Glacier and the Bransfield Strait are the most studied. The manifestations of Late Mesozoic-Cenozoic alkaline-ultrabasic and alkaline-basaltoid magmatism serve as geological evidence of rifting processes.
Minerals of Antarctica
Manifestations and signs of minerals were found in more than 170 points of Antarctica (map).
Of this number, only 2 points in the Commonwealth Sea area are deposits: one is iron ore, the other is coal. Among the rest, over 100 occur in occurrences of metallic minerals, about 50 in occurrences of non-metallic minerals, 20 in occurrences of coals, and 3 in gas occurrences in the Pocca seas. About 20 manifestations of metallic minerals were identified by elevated contents of useful components in geochemical samples. The degree of knowledge of the vast majority of manifestations is very low and most often comes down to a statement of the fact of the discovery of certain mineral concentrations with a visual assessment of their quantitative content.
Combustible minerals are represented by hard coal on the mainland and gas shows in wells drilled on the shelf of the Pocca Sea. The most significant accumulation of coal, regarded as a deposit, is located in East Antarctica in the area of the Commonwealth Sea. It includes 63 seams of coal in an area of about 200 km 2, concentrated in the section of the Permian strata with a thickness of 800-900 m. The thickness of individual coal seams is 0.1-3.1 m, 17 seams are over 0.7 m and 20 - less than 0.25 m. Consistency of the layers is good, the dip is gentle (up to 10-12°). According to the composition and degree of metamorphism, coals belong to duren high- and medium-ash varieties, transitional from long-flame to gas. According to preliminary estimates, the total reserves of hard coal in the deposit can reach several billion tons. In the Transantarctic Mountains, the thickness of coal-bearing strata varies from several tens to hundreds of meters, and the degree of coal saturation in sections varies from very weak (rare thin lenses and interlayers of carbonaceous shale) to very significant (from 5-7 to 15 layers in the interval of the section with a thickness of 300-400 m). The formations have a subhorizontal occurrence and are well sustained along strike; their thickness, as a rule, is from 0.5 to 3.0 m, and in single blows it reaches 6-7 m. The degree of metamorphism and composition of coals are similar to those given above. In some areas, semi-anthracites and graphitized varieties are noted, associated with the contact effect of dolerite intrusions. Gas shows in boreholes on the Pocca shelf were found in the depth range from 45 to 265 meters below the bottom surface and are represented by traces of methane, ethane and ethylene in the Neogene glacial-marine sediments. On the shelf of the Weddell Sea, traces of natural gas were found in one sample of bottom sediments. In the mountainous frame of the Weddell Sea, epigenetic light bitumens are present in the rocks of the folded basement in the form of microscopic veinlets and nest-like accumulations in cracks.
metal minerals. Iron concentrations are represented by several genetic types, of which the largest accumulations are associated with the Proterozoic jaspilite formation. The main jaspilite deposit (deposit) was discovered in the overglacial outcrops of Prince Charles City over a length of 1000 m at a thickness of more than 350 m; in the section, there are also less thick members of jaspilites (from fractions of a meter to 450 m), separated by layers of waste rock up to 300 m thick. 0 times. The amount of silica varies from 35 to 60%, the content of sulfur and phosphorus is low; as impurities are noted, (up to 0.2%), as well as and (up to 0.01%). Aeromagnetic data indicate the continuation of the jaspilite deposit under the ice for at least several tens of kilometers. Other manifestations of this formation are represented by thin primary deposits (up to 5-6 m) or moraine collapses; the content of iron oxides in these manifestations varies from 20 to 55%.
The most significant manifestations of metamorphogenic genesis are represented by lenticular and nest-like almost monomineral accumulations 1–2 meters in size with a content of up to 90%, localized in zones and horizons several tens of meters thick and up to 200–300 m long. Approximately the same scales are typical for manifestations of contact -metasomatic genesis, but this type of mineralization is less common. Manifestations of magmatogenic and hypergene genesis are few and insignificant. Manifestations of other ores of ferrous metals are represented by titanomagnetite dissemination, sometimes accompanying igneous accumulations of iron with thin manganese crusts and efflorescences in the zones of crushing of various plutonium rocks, as well as small nest-like accumulations of chromite in serpentinized dunites on the South Shetland Islands. Increasing concentrations of chromium and titanium (up to 1%) revealed some metamorphic and basic intrusive rocks.
Relatively large manifestations are characteristic of copper. Of greatest interest are manifestations in the southeastern zone of the Antarctic Peninsula. They belong to the porphyry copper type and are characterized by disseminated and veined (rarely nodular) distribution of , and , sometimes with an admixture of and . According to individual analyzes, the copper content in intrusive rocks does not exceed 0.02%, but in the most intensely mineralized rocks it increases to 3.0%, where, according to rough estimates, up to 0.15% Mo, 0.70% Pb, 0, 07% Zn, 0.03% Ag, 10% Fe, 0.07% Bi and 0.05% W. in the manner of pyrite-chalcopyrite-molybdenite with an admixture of pyrrhotite); however, manifestations in this zone are still poorly understood and not characterized by analyses. In the basement of the East Antarctic Platform in the zones of hydrothermal development, the thickest of which on the coast of the Sea of Cosmonauts have a thickness of up to 15-20 m and a length of up to 150 m, sulfide mineralization of the vein-disseminated type develops in quartz veins. The maximum size of ore phenocrysts, composed mainly of chalcocite, chalcopyrite and molybdenite, is 1.5-2.0 mm, and the content of ore minerals in the most enriched areas reaches 5-10%. In such areas, the copper content increases to 2.0 and molybdenum to 0.5%, but poor dissemination with traces of these elements (hundredths of a percent) is much more common. In other regions of the craton, less extensive and thick zones are known with mineralization of a similar type, sometimes accompanied by an admixture of lead and zinc. The remaining manifestations of metallic ones are their somewhat increased content in geochemical samples from the above-described ore occurrences (as a rule, no more than 8-10 clarks), as well as an insignificant concentration of ore minerals found during the mineragraphic study of rocks and analysis of their heavy fraction. Only gives visual accumulations, the crystals of which are no more than 7-10 cm in size (most often 0.5-3.0 cm) are noted in pegmatite veins in several areas of the East Antarctic Platform.
Of the non-metallic minerals, crystal is the most common, the manifestations of which are associated mainly with pegmatite and quartz veins in the basement of the craton. The maximum size of the crystals is 10-20 cm in length. As a rule, quartz is milky white or smoky; translucent or slightly turbid crystals are rare and do not exceed 1-3 cm in size. Small transparent crystals were also noted in tonsils and geodes of Mesozoic and Cenozoic balsatoids in the mountainous frame of the Weddell Sea.
From modern Antarctica
The prospects for the discovery and development of mineral deposits are sharply limited by the extreme natural conditions of the region. This concerns, first of all, the possibility of discovering deposits of solid minerals directly in the overglacial outcrops of rocks; their negligible degree of prevalence reduces the probability of such discoveries by dozens of times in comparison with other continents, even under the condition of a detailed examination of all rock outcrops in Antarctica. The only exception is hard coal, the stratiform nature of the deposits of which among the undislocated deposits of the cover determines their significant areal development, which increases the degree of exposure and, accordingly, the probability of finding coal seams. In principle, detection of subglacial accumulations of certain types of minerals is possible with the help of remote methods, but prospecting and exploration, and even more so operational work in the presence of continental ice, is still unrealistic. Building materials and coal on a limited scale can be used for local needs without significant costs for their extraction, transportation and processing. There are prospects for the development in the foreseeable future of potential hydrocarbon resources on the Antarctic shelf, however, there are no technical means for exploiting deposits in extreme natural conditions typical of the shelf of the Antarctic seas; moreover, there is no geological and economic substantiation of the expediency of creating such facilities and the profitability of the development of the bowels of Antarctica. There is also insufficient data to assess the expected impact of exploration and development of minerals on the unique natural environment of Antarctica and to determine the admissibility of such activities from an environmental standpoint.
South Korea, Uruguay, . 14 parties to the Treaty have the status of consultative parties, i.e. states that have the right to participate in regular (every 2 years) consultative meetings on the Antarctic Treaty.
The objectives of the consultative meetings are the exchange of information, the discussion of issues related to Antarctica and of mutual interest, as well as the adoption of measures to strengthen the Treaty system and comply with its goals and principles. The most important of these principles, which determine the great political significance of the Antarctic Treaty, are: the use of Antarctica forever exclusively for peaceful purposes and the prevention of its transformation into an arena or an object of international disputes; prohibition of any measures of a military nature, nuclear explosions and the dumping of radioactive waste; freedom of scientific research in Antarctica and promotion of international cooperation there; protecting the environment of Antarctica and preserving its fauna and flora. At the turn of the 1970-80s. within the framework of the Antarctic Treaty system, the development of a special political and legal regime (convention) for the mineral resources of Antarctica has begun. It is necessary to regulate activities for the exploration and development of minerals in Antarctica in the case of industrial development of its bowels without damage to the natural environment of Antarctica.
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