RosGeo has discovered new polymetallic massive sulfide deposits on the Atlantic ocean floor

St. Petersburg, February 7, 2020. Geologists of the Ocean exploration survey department of Polar Marine Geosurvey Expedition JSC (PMGE, a Rosgeo subsidiary) discovered two new hydrothermal ore fields of deep-sea polymetallic massive sulfides in the Atlantic, called Korallovoye and Molodezhnoye.

The polymetallic sulfide ore samples for a total weight of about 150 kg were lifted aboard the Professor Logachev research vessel from the Korallovoye hydrothermal field at a depth of more than 3500 m.

"The expedition focused on exploring for ores in the most interesting and promising southern cluster of the Russian exploration area, where deep rocks of the Upper Mantle come to the seafloor surface and the largest polymetallic sulfide deposits could be discovered," — Dmitry Kaminsky, Managing Director of PMGE. "Three large ore occurrences have been earlier discovered in this area of the Mid-Atlantic Ridge. New discoveries by Rosgeo will increase the resource potential of the southern cluster within the Russian exploration area and be crucial for planning the further explorations and future field development.”

At the first stage of research in December 2019, the Professor Logachev vessel was engaged in the systematic searching for geophysical anomalies of natural electrical field that form by oxidation of sulfide ores and are an important indicator. The searching procedure was developed in PMGE; therewith, the measurements in the near-bottom part of the water layer were carried out using a special deep submergence vehicle MAK-1M made by Yuzhmorgeologiya JSC. The multiday research identified two large promising areas in close proximity to each other.

At the further stage the promising areas were explored using a deep-sea television equipment. These explorations found an extensive domal uplift with active "black smokers" – pipe formations up to 1.5 m high which emit hot suspended ore substance in the form of black smokes, as well as numerous residues of inactive pipes and sulfide ore outlets. Then, the numerous ore samples were lifted aboard the vessel using a rock dredge. It included rich massive copper ores and numerous vein-disseminated ores.

The nearest plans of the expedition are to test the open ore fields in detail using a TV grab, to study polymetallic ore samples on the vessel and in fixed-state laboratories, and to generate geological maps.