MINDeSEA WP6 Polymetallic Nodules (Point)

Polymetallic nodules occur in abyssal plains (~4000 – 6000 mm water depth) of all major oceans as two-dimensional deposits, formed on or just below sediment-covered seafloor, rich in metals of economic interest such as manganese (Mn), nickel (Ni), copper (Cu), cobalt (Co), molybdenum (Mo), titanium (Ti), lithium (Li), and rare earth elements (REE). The nodules are generated in marine environments where the sedimentation rates are low, commonly less than 10 centimeters (cm) per thousand years. The nodules consist of micro-layers of Mn oxides and Fe oxy-hydroxides concentrically precipitated around a nucleus. Nodules are generally about golf ball sized, most commonly 1–12 cm in diameter, but can vary in diameter from millimeter-size (micronodules) to as large as 20 cm. The polymetallic nodules are formed by metals precipitation either from ambient seawater (hydrogenetic formation), from pore-waters in the sediments (diagenetic formation), from hydrothermal derived fluids (Bonatti and Nayudu, 1965; Bau et al., 2014; Kuhn et al., 2017) and the formation processes that represent a mix of these different end-member processes. The formation mechanisms control the general chemical composition of the nodules, e.g. the hydrogenetic precipitation leads to an enrichment of Co and REE while the diagenetic precipitation favours enrichment of Ni and Cu. Hydrogenetic nodules grow remarkably slow (1 to 5 mm per million years), whereas diagenetic nodules grow at rates up to 250 mm per million years.

Citation proposal
(2019) . MINDeSEA WP6 Polymetallic Nodules (Point). https://services.mspdata.eu:/geonetwork/srv/api/records/5ee0d410-2aac-4328-9f37-390c0a010833

Date ( Creation ): 2019-04-27

Date ( Publication ): 2019-04-27

Date ( Revision ): 2020-04-27

Edition: MINDeSEA WP6

Codespace: https://www.europe-geology.eu/

Presentation form: modelDigital Digital model

Purpose: The main objective of MINDeSEA WP6 is to compile, analyse and deliver the information (generated data, products and metadata from areas explored and investigated) on the existing occurrences of polymetallic nodules in the European margins, in order to assess the European resource potential and inventory on polymetallic nodules. The compiled data will be made available through a common European information portal. The portal will provide access to data and metadata held by each organisation based on standards developed in the Geo-Seas and EMODnet-Geology project and data products compiled at a scale of 1:250,000 and more detailed scale when possible. This WP will also provide the basis for polymetallic nodules prospect identification and evaluation in European waters and identify key areas of missing information for future exploration and prospective mapping. The specific objectives of MINDeSEA WP6 are: - Characterize each polymetallic nodules occurrence, by compiling relevant data of the nodules generation controlling parameters, such as: location, geological setting, bathymetry, backscatter, sediment thickness, as well as the extend and depth of occurrence of Mn nodules. Morphology, textural characteristics, mineralogy and chemical composition and age data of the polymetallic nodules. Also to be compiled, if available, data from the surrounding sediments (type, composition, age, sedimentation rate, etc.). - To generate a harmonised dataset from the compiled data (harmonised mineral maps and databases) of polymetallic nodule occurrences. - Characterize the trace elements content of the several polymetallic nodules deposit types including the Critical Raw Materials (CRM) for base, noble and technological metals. Controlling factors on the occurrence of CRM will also be characterized. - Identify the principal metallogenic provinces where such deposits occur, taking into account spatial and temporal attributes, and provide models of formation.

Principal investigator

National Laboratory of Energy and Geology (LNEG) - Pedro Ferreira

Laboratório Nacional de Energia e Geologia Estrada da Portela Bairro do Zambujal 2610-999 Amadora Portugal

+351-210-924-600

Website: https://www.lneg.pt/en/homepage/

Maintenance and update frequency: annually Annually

GEMET - INSPIRE themes, version 1.0 ( Theme )

Sea regions

Spatial scope ( Theme )

European

GeoERA Keyword Thesaurus ( Theme )

sedimentary material , sand , mud , claystone , sandstone , clay , basalt , manganese , iron , baryte , potassium

European Geoscience Registry - Projects ( Theme )

MINDeSEA

INSPIRE theme register ( Theme )

Mineral resources

GeoERA Projects ( Theme )

MINDeSEA

GEMET - Themes, version 4.1.4, 13 Feb 2020 ( Discipline )

earth science

GEMET - Themes, version 4.1.4, 13 Feb 2020 ( Discipline )

geology

GEMET - Themes, version 4.1.4, 13 Feb 2020 ( Place )

marine geology