St. Petersburg, February 7, 2020. The geologists from Marine Exploratory Surveying Crew of JSC Polar Marine Geosurvey Expedition (PMGE, a subsidiary of JSC Rosgeologiya) discovered at the seabed of the Atlantic Ocean two new hydrothermal ore fields of deep-sea polymetallic sulphides called Korallovoe and Molodezhnoe.
The samples of the sulphide polymetallic ore of about 150 kg total weight have been lifted up on board of the research vessel “Professor Logachev” out of the hydrothermal field Korallovoe from more than 3.500 m depth.
“The objective of current expedition is ore prospecting in the most interesting and promising southern cluster of the Russian exploration area (REA), where deep-seated rocks of the Earth’s upper mantle extend to the seabed surface, and the largest deposits of polymetallic sulphides can be discovered,” - said Mr. Dmitry Kaminsky, managing director of JSC PMGE. – Earlier in this part of the Mid-Atlantic Ridge 3 large ore occurrences have already been discovered. The new discoveries of Rosgeologiya allow to increase the resource potential of the southern REA cluster and will be of great importance for planning of further studies and subsequent development of the fields.”
At the first stage of surveys in December 2019 the “Professor Logachev” conducted a methodical prospecting of geophysical anomalies of the natural electric field that occur during the oxidation of sulphide ores, and represent a significant prospecting indicator. The prospecting technique was developed by PMGE experts, and near-bottom measurements were carried out using the specialized deep-submergence vehicle MAK-1M developed by JSC Yuzhmorgeologiya. The surveys lasting for many days have resulted in discovery of two large promising zones located not far from each other.
At the next stage, the promising zones were studied with application of the deep-sea television equipment. There have been discovered an extensive domal upwarping with active “black smokers” – formations shaped as pipes up to 1.5 m high emitting hot suspended ore substance in the form of black “smokes”, as well as numerous remains of inactive pipes and sulphide ore outcrops. After that, numerous ore samples were hoisted aboard the vessel with application of the rock dredge: rich massive copper ores and multiple stringer-porphyry mineralization ores.
The expedition immediate plans include the detailed sampling of discovered ore fields by the telegrab, studying the polymetallic ore samples on the vessel and in stationary laboratories, and elaboration of geological maps.
The R/V “Professor Logachev” arrived in the marine operations area in December 2019 and began surveys of the geological structure of the ocean bed section – 18 blocks of the Russian exploration area of about 1800 km2 total area
The expedition purpose is to complete a set of geological-geophysical surveys on identification of promising ore occurrences in the axial zone of the Mid-Atlantic Ridge, sampling of deep-sea polymetallic sulphides within the first 6-year stage of the Contract with the International Seabed Authority signed by the Ministry of Natural Resources of the Russian Federation in 2012 for a period of 15 years.
Previously, PMGE geologists examined 82 of 100 REA blocks, where they discovered and studied 12 ore objects with inferred resources of 104.8 mln tons of copper-zinc and copper-sulphide ore specialization. According to geologist’s estimates, the ore of these objects contains 3,949.5 thous. tons of copper, 738.4 thous. tons of zinc, 119 tons of gold, and 1,679.7 tons of silver.
Within the southern REA cluster, which includes 36 blocks, Ashadze ore cluster was discovered in 2003, Semenov ore cluster in 2007, and Irinovskoe ore field in 2011.
Following the Contract, upon discovery of priority promising areas for performance of detailed prospecting activities, as well as conducting a full-scope geological analysis of the actual data for all REA-DPS 100 blocks, in September 2020, it will be necessary to justify the selection of 50 blocks, that are the most promising in terms of sulphide ore deposits, and reasonably withdraw from 50 least prospective ones.
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Rosgeo is a Russian multidisciplinary geological holding company which provides a full range of geological exploration services from regional surveys to stratigraphic drilling and subsoil monitoring. The holding company has unique expertise, including in such areas as marine geology and offshore operations. The holding company's enterprises have discovered more than 1,000 fields and deposits, including large hydrocarbon and mineral deposits. 100% of Rosgeo’s shares are held by the Russian government.
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