IBERLID: A lead isotope database and tool for metal provenance and ore deposits research

[EN] Although sometimes controversial, the use of Pb isotope data in geological research of ore deposits and metal provenance studies in archaeology has proved a useful tool for investigation of the relations between ore sources and raw materials used by humans. Users of this kind of information have often asked for complete datasets that would include not only numerical values of isotope ratios but also mineralogical and geological information about the samples analysed so as to allow for conscientious data comparison. The IBERLID database here presented has been designed to include available information for nearly 3000 samples from the Iberian Peninsula and Balearic Islands in a unique, complete to the extent possible, upgradable dataset using standardized variables. This allows to compare data and establish groups based upon isotopic ratios, mineralogy and other geological characteristics of the samples. The database is available through an online interactive public tool (www.ehu.eus/ibercron/iberlid) that provides for data search, comparison and graphics design, and may be furthermore exported for enhanced statistical treatment. By direct use of the proposed standardized variables, the compiled results allow to discern among 3 main mineralization events within the Iberian realm, while interpolation of Pb isotope data allow to draw the first maps of model age, mu and kappa parameters. The problem of radiogenic lead in some compiled data requires additional analyses of elemental concentrations, which so far has been generally neglected.Financial support was provided by the Spanish Ministry of Economy, Industry and Competitiveness, and the European Regional Development Fund (MINECO/ERDF CGL2015-63530-P) , and by the UPV/EHU (GIU15/05) . The authors are grateful to Sabine Klein and two anony-mous reviewers for constructive comments which improved this manuscript, and to Huayong Chen for suggestions and editorial handling

Calako skarn-a: ezaugarri geokimikoak eta U-Pb datazioak

Cala mine is located in the southwest of the Iberian Massif, in the Ossa-Morena Zone (OMZ). Due to the complexity of its mineralisation, there has been much debate in recent years but, according to recent studies, it is interpreted that part of the mineralisation is related to a calcic skarn that outcrops nearby. In this work, garnets from this skarn have been dated using the U-Pb geochronology by LA-ICP-MS, and the obtained age is 335 ± 1 Ma. Calcic garnets (Gros52-59Andr40-44) show homogeneous major elements distribution. A weak chemical zonation can be observed in trace elements and REE, more evident in trivalent elements. This chemical homogeneity has been related to a stable system, where P-T conditions have remained quite stable.; Cala meategia Ossa-Morena Zonaldean (OMZ) kokatzen da, Iberiar Mazizoaren hego-mendebaldean. Hango mineralizazioa nahiko konplexua denez, az- ken urteotan asko eztabaidatu da horren inguruan, baina berriki egin diren ikerketa- lanen arabera, mineralizazioaren zati bat bertan azaleratzen den skarn kaltziko bate- kin erlazionatuta dagoela interpretatu da. Lan honetan skarn-eko granateak datatu dira U-Pb sistema eta LA-ICP-MS metodoaren bidez. Mineral horiek primarioak direnez, metasomatismoa datatzea ere posible izan da skarna bera ere datatuz. Lortutako emai- tzen arabera skarna duela 335 ± 1 Ma sortu zela ondorioztatu da. Granate kaltzikoen (Gros52-59Andr40-44) konposizio kimikoa nahiko homogeneoa da, batez ere elementu nagusiak aztertzean, eta aztarna elementuen zein REE-en kontzentrazioak zonazio oso ahula erakusten dute, batik bat elementu tribalenteetan. Honenbestez, granate hauen so- rreran sistemako P-T baldintzak nahiko konstante mantendu zirela ondorioztatu da

Geochemical dataset of high-pressure acid migmatites from the Cabo Ortegal Complex (NW Spain)

This brief note presents geochemical data from rock samples from the Cabo Ortegal Complex (NW Spain). The samples belong to acid lithologies within the mainly basic to intermediate granulite unit that have been poorly investigated so far. For this communication, five samples of the migmatites and an amphibolitic enclave within them have been analysed. The whole-rock major and trace-element analyses were accomplished by means of Q-ICPMS. The dataset provides new and useful information relevant to the origin of the acid migmatites and can be used in addition to information from neighbouring lithologies to enhance understanding of the geological evolution of the Western Variscan Belt