The article presents the results of experimental studies of the sorption and desorption of rare-earth metal (REM) cations by the Co-bearing ferromanganese crusts of the Govorov Guyot. It has been established that the REM cations are sorbed on the CFC ore minerals (Fe-vernadite, vernadite, Mn-feroxyhite, and goethite. The crusts are characterized by high exchange capacity (1.78–3.57 mg-equiv/g, which increases in the following series: (Dy < Gd < Lu < Sm < Nd < Y, La < Eu) ≪ Ce. The REM cation sorption proceeds by the irreversible ion-exchange equivalent mechanism. The exchange complex of ore minerals consists of Na+, K+, Ca2+, and Mg2+ cations, which contribute 97‒98

Data on the mineral and chemical composition of samples of sulfide deposits from the Broken Spur and TAG (Mid-Atlantic Ridge) are presented. The main minerals in the Broken Spur field are marcasite, pyrrhotite, pyrite, chalcopyrite, and sphalerite; in sample from TAG: chalcopyrite, pyrite, and marcasite. It has been established that these sulfide minerals of Fe, Cu, and Zn are natural ion exchangers and belong to the class of adsorbents. Exchange capacity of sulfide minerals in terms of heavy metal cations (Ni2+, Co2+, Cd2+, and Pb2+) is 0.022–0.32 mg-equiv/g. In the exchange reaction products, the mineral composition of sulfide deposits is retained, and new phases do not appear. It is suggested that the adsorbed heavy metal cations populate either vacant cationic or interstitial defect sites in the structures of sulfide minerals. Bond strength of the adsorbed heavy metal cations with the main structural elements of minerals is low, which is confirmed by their high extraction in an acid medium. The results of adsorption-desorption experiments indicate two forms of heavy metal cations in sulfide minerals: adsorbed (basic) and chemically bound.

The article describes the geological conditions of the formation of cobalt-rich ferromanganese crusts on the Govorov guyot in the Magellan Seamount system of the Pacific Ocean. It is established that the crusts are deposited on dense organogenic-clastic limestones, breccias, and volcanoclastic rocks. Crusts are three-or four-layer formations. The main ore minerals of all layers of crusts are Fe-vernadite, vernadite and Mn-feroxyhyte. It has been found that the Fe content increases and Mn content decreases from layer I-1 to layer III. For the ore cations of metals—Co2+, Ni2+, Cu2+—no regularity in their distribution has been established: in some crusts, their content decreases from layer I-1 to layer III, while in others, it increases. The most stable content of heavy metal cations in the guyot crusts is Zn2+, Mo6+, Sr2+, Cd2+, Ba2+, and Pb2+. The distribution of rare-earth metal cations in the layers of different crusts is not the same and does not coincide with the distribution of Fe(III). And only for Ce3+ is its distribution is close to that of another ore—forming element of crusts—Mn(IV). It was found that the increased and maximum (1.08 g/t) Pt content is observed in layer II, the minimum in layer III of crusts.

The article presents the results of experimental studies of the sorption properties of ferromanganese crusts (CMC) of Kotzebue guyot relative to rare earth metal cations (REM). It is established that the crusts are a natural highly selective sorbent of REM cations. The sorption of REM cations occurs on ore minerals ‒ Fe-vernadite, vernadite, Mn-feroxigite, goethite. The crusts are characterized by a high exchange capacity – 1.67‒3.28 mg-eq/g, which increases in the series: Lu Gd Dy La, Sm Nd Y Eu) ⪡ Ce. Absorption of REM cations proceeds by an ion-exchange equivalent mechanism, in the case of Ce3+ cations ‒ according to the superequivalent mechanism with respect to the cations of the exchange complex of ore minerals ‒ Na+, K+, Ca2+, Mg2+, Mn2+, Ni2+, which contribute 95–98% to the total capacity of minerals.

The results of experimental studies of the sorption properties of ferromanganese crusts on the Kocebu Guyot relative to rare-earth metal (REM) cations are presented. It is established that the crusts are a natural, highly selective sorbent of REM cations. The REM cations are adsorbed on ore minerals (Fe-vernadite, vernadite, Mn-feroxyhyte, and goethite). The crusts are characterized by a high exchange capacity (1.67‒3.28 mg-equiv/g), which increases in the series: Lu < Gd < Dy < La, Sm < Nd < Y < Eu ≪ Ce. The REM cations are adsorbed by the ion-exchange equivalent mechanism—in the case of Ce 3+ cations, according to the superequivalent mechanism with respect to cations of the exchange complex of ore minerals—Na + , K + , Ca 2+ , Mg 2+ , Mn 2+ , and Ni 2+ , which contribute 95–98

The main ore minerals of all layers of cobalt-rich ferromanganese crusts of Guyot Govorov of the Magellanic Mountains of the Pacific Ocean are poorly crystallized, poorly structurally ordered Fe-vernadite, Mn-feroxigite. A sufficiently structurally ordered vernadite, which is mainly found in layer I–1 and in a smaller amount in layer I–2, has also been identified as goethite. As an impurity, asbolan-buzerite and buzerite-I are noted. The distribution of cations of non-ferrous, heavy, rare, and rare-earth elements in the layers of Govorov Guyot crusts indicates that they are clearly unevenly supplied to the cobalt-rich ferromanganese crusts.

The article presents data on the study of cation exchange properties of sediments in the Central depression of the Barents Sea relative to heavy metals. The experiments were carried out both on sediments of natural moisture and on sediments after removal of sludge water. The maximum values of the equilibrium exchange capacity of sediments containing and not containing silt water practically coincide and are (in mg-eqv/g) in Mn, Ni, Zn, Cd – 0.20-0.28; Pb – 0.28-0.40; Cu – 0.36-0.66. According to the obtained values of the exchange capacity of precipitation belong to the class of adsorbents. The influence of sediments size and concentration of metal salt solutions on the exchange capacity of precipitation was studied. It is concluded that, on the one hand, precipitation contributes to the circulation of heavy metal cations in the marine environment, on the other hand, sediments can be considered as cleaners and pollutants of marine waters.

This work presents data on the study of the sorption of heavy metal cations in sediments of the Central Depression of the Barents Sea. During experiments the naturally moistened sediments of different fractions and those after squeezing out the interstitial water were studied. The maximum values of the equilibrium exchange capacity of sediments containing interstitial water and those free of it are in close agreement with each other. The capacity increases in the series (Mn < Ni < Zn < Cd) < (Pb < Cu) and ranges from 0.30 Mn to 0.71 Cu mg-eqiv/g. According to the values obtained, the studied sediments can be classified as adsorbents. The influence of grain size and mineral composition of sediments and the concentration of solutions of metal salts on the absorption capacity of sediments was studied. It was concluded that sediments can be considered as both cleaners and pollutants of marine waters.

Приводятся данные по изучению сорбции катионов тяжёлых металлов на осадках Центральной впадины Баренцева моря. Эксперименты проводили на осадках натуральной влажности и после удаления из них иловой воды на отдельных классах крупности осадков. Максимально установленные значения равновесной обменной ёмкости осадков, содержащих и не содержащих иловую воду, практически совпадают между собой. Ёмкость осадков возрастает в ряду (Mn < Ni < Zn < Cd) < (Pb < Cu) и составляет от 0,30 по Mn до 0,71 мг-экв/г по Cu. По полученным значениям ёмкости осадки относятся к классу адсорбентов. Изучено влияние крупности, минерального состава осадков и концентрации растворов солей металлов на поглотительную способность осадков. Сделан вывод, что осадки можно рассматривать как очистители, так и как загрязнители морских акваторий.

It has been established that the Co-bearing manganese crusts and crust‒nodule formations in Pacific gyouts are natural, highly selective sorbents of REM (Ce 3+ , Y 3+ , La 3+ ) cations. Exchange capacity of ore minerals (vernadite, Fe-vernadite, and Mn-feroxyhyte) increases in the series La 3+ < Y 3+ < Co 2+ < Ce 3+ and its mean value increases from 1.67 (La 3+ ) to 2.84 (Ce 3+ ) mg-equiv/g, which is a high indicator for the natural mineral ion exchangers. In the course of sorption, ore minerals of crusts display a higher selectivity to Ce 3+ cations than to Y 3+ and La 3+ cations. Age of ore minerals does not influence their sorption properties relative to REM cations.

Cobalt-rich manganese crusts and crust-concretion formations from the guyots of the Pacific Ocean were found to be the natural highly selective sorbents of rare-earth cations Ce3+, Y3+, La3+. Ion exchange capacity of ore minerals — vernadite, Fe-vernadite and Mn-ferroxyhyte — increases in the following sequence La3+

The mineralogy and geochemistry of a fragment of an active hydrothermal edifice from the Hydrothermal Hill of the Southern Trough valley of the Guaymas Basin in the Gulf of California were studied. The sample was collected from a depth of 1995 m by the Pisces manned submersible on cruise 12 of the R/V Akademik Mstislav Keldysh, Institute of Oceanology, Russian Academy of Sciences. The fragment and the edifice itself consists of two accrete pipes: ore (pyrrhotite) and barren (carbonate) combined in a single edifice by an outer barite–opal zone. The ore edifice is located in the rift zone of the Guaymas Basin with a thick sedimentary cover and is depleted in metals in comparison with ores from rift zones of the open ocean, which are not blocked by sedimentary deposits. This is explained by loss of metals at the boundary between hot sills and sedimentary rocks and by the processes of interaction of hydrothermal solutions with sedimentary deposits. The sedimentary series faciitates long-term preservation of endogenous heat and the ore formation process. Ore edifices of the Guaymas Basin are mostly composed of pyrrhotite, have a specific set of major elements, microelements and REEs, and contain naphthenic hydrocarbons. They may be search signs of hidden polymetallic deposits, considered to be the roots of ore occurrences localized under the surface of the bottom in young active rifts with high spreading and sedimentation rates, i.e., in near-continental areas of rifts of the humid zone with avalanche sedimentation.

The Marcus Wake and Magellan guyots formed about 129–74 Ma ago at 10°–30° S and drifted 1700–4400 km to their present-day latitudinal position across the equatorial zone of maximum deposition. Cooling of the Pacific plate brought these guyots to the northern arid zone during the Turonian–Maastrichtian, to depths at which sediment accumulation rates were low and the conditions promoted precipitation of Co-rich Fe–Mn crusts from the Campanian to the present. Nonprecipitation of Co-rich Fe–Mn crusts during the Oligocene was caused by the action of bottom currents. The presence of a hiatus identified in cores from drill holes was used as the basis for reconstruction of the directions of bottom currents in the Oligocene.

Показано, что реакционная способность катионов металлов рудных минералов железомарганцевых корок поднятия Маркус-Уэйк возрастает в ряду: (Co2+ 2+ 2+) 2+ 2+ + Ca2+ Na+). Состав обменного комплекса рудных минералов корок постоянен и состоит из указанных выше катионов металлов. Наибольший вклад в обменную ёмкость рудных минералов вносят катионы Са2+, Na+. Ёмкость минералов корок по катионам щелочных и цветных металлов 0,43-0,60 и 2,08-2,70 мг-экв/г соответственно. Установлено, что обменная ёмкость рудных минералов по катионам цветных металлов возрастает прямолинейно при увеличении содержания в корках MnO2 и не зависит от географического расположения гайотов Маркус-Уэйк.

It is shown that the reaction ability of metal cations of ore minerals in Fe–Mn crusts of the Marcus Wake Rise increases in the following manner: (Co2+ < Cu2+ < Ni2+) < (Mg2+ < Mn2+ < K+ ≈ Ca2+ ≈ Na+). The composition of the exchange complex of the ore minerals is constant and includes these metal cations. Ca2+ and Na+ are major contributors to the exchange capacity of the ore minerals. The capacity of the ore minerals by cations of alkali and base metals is 0.43–0.60 and 2.08–2.70 mg-equiv/g, respectively. The exchange capacity of the ore minerals by cations of base metals increases linearly with the increase in the MnO2 content of the crust and does not depend on the geographical locations of the Marcus Wake guyots.

Co-bearing manganese crusts (CMCs) from the Govorov and Volcanologist guyots (Magellan Seamounts, Pacific Ocean) are of the same type and consist of three layers (I-1, II, III) and a “dried crust” variety of layer III. It is shown that the structural and textural pattern are quite similar within individual layers. The major ore minerals of the crusts are poorly crystallized, have a low degree of structural ordering, and include Fe-vernadite, Mn-feroxyhyte, and less abundant, well-crystallized, and structurally ordered vernadite. It is shown that the cations of ore (Со, Ni, Cu), rare, and rare-earth metals are irregularly concentrated in ore minerals of CMCs, which provides evidence for the pulsating nature of their supply at different geological stages.