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This paper highlights the geodynamic evolution of the early Precambrian rock associations in the northwestern part of the Russian Arctic where the rocks are exposed in the Kola region (northeastern Baltic Shield). The evolution is shown to predetermine the metallogenic potential of the area. It is emphasized that the Earth’s evolution is a non-linear process. Thus, we cannot draw direct analogies with Phanerozoic time or purely apply the principle of actualism, which is still widely used by experts in Precambrian geology to study the premetamorphic history of ancient deposits. In both cases, the principles should be adjusted. This article provides a novel technique for reconstructing geodynamic regimes of protolith formation in the early Precambrian. The technique identifies changing trends in geodynamic regimes during the formation of the Archean structural and compositional complexes in the Kola region. These trends fit into the earlier suggested general scheme of their formation, thus enhancing its reliability. The metallogeny of the ore areas is specified. The results of the geodynamic reconstructions explain most of the location patterns of minerals within the Kola region. Thus, the authors consider the metallogenic forecast based on geodynamic reconstructions to be a promising trend for further research.

The Paulo Lopes Suite (SPL), composed of the Paulo Lopes Granite (GPL), Garopaba Granitoids (GG) and Silveira Gabbro (GS), is an association of contemporaneous acid and basic rocks, comprising monzo and syenogranites associated to basic dikes, with abundant mafic microgranular enclaves, interpreted as co-mingling products. The contacts between the granitoids and the basic rocks are evidences of coeval and interactive magmas. The Silveira Gabbro occurs in the study area as a main body and several narrow dikes of NNE orientation. Field relations define a chronological order of magmatic events, where the GPL is the first magmatic pulse and, while steel partially crystallized, was intruded by mingled magmas, represented by the GG and the GS. The basic components are medium-grained, equigranular rocks, with subophitic and ophitic textures. The centre of the main body contains medium- to coarse-grained, equigranular rocks, where agglomerates of early-formed clinopyroxene and plagioclase crystals are found. In the chilled margins, they are microporphyritc rocks of aphanitic groundmass, indicative of rapid crystallization. The Silveira Gabbro rocks are composed of labradorite-andesine, orthopyroxene, augite, pigeonite, olivine (occasionally serpentinized), Fe-hornblende and magnesian hornblende, red biotite, magnetite, ilmenite, apatite, and baddeleyite. The composition is tholeiitic, similar to the high-Ti-P basalts of the Serra Geral Formation. Their high contents of K, Rb, Sr and Ba, as well as negative anomalies of Nb and Ta in multielemental diagrams are similar to the ones observed in magmatic rocks from mature arcs or post-collisional environments. The Neoproterozoic basic rocks may be discriminated from the ones belonging to the Cretaceous Serra Geral Formation by their higher contents of alcalis, Cs, U, Th, and by their fractionated REEpatterns, expressed in the La/LuN ratio. The associated granitoids are structural and compositionally compatible with the ones found in post collisional settings, which indicates that the SPL magmatism developed in such environment.

The Paulo Lopes Suite (SPL), composed of the Paulo Lopes Granite (GPL), Garopaba Granitoids (GG) and Silveira Gabbro (GS), is an association of contemporaneous acid and basic rocks, comprising monzo and syenogranites associated to basic dikes, with abundant mafic microgranular enclaves, interpreted as co-mingling products. The contacts between the granitoids and the basic rocks are evidences of coeval and interactive magmas. The Silveira Gabbro occurs in the study area as a main body and several narrow dikes of NNE orientation. Field relations define a chronological order of magmatic events, where the GPL is the first magmatic pulse and, while steel partially crystallized, was intruded by mingled magmas, represented by the GG and the GS. The basic components are medium-grained, equigranular rocks, with subophitic and ophitic textures. The centre of the main body contains medium- to coarse-grained, equigranular rocks, where agglomerates of early-formed clinopyroxene and plagioclase crystals are found. In the chilled margins, they are microporphyritc rocks of aphanitic groundmass, indicative of rapid crystallization. The Silveira Gabbro rocks are composed of labradorite-andesine, orthopyroxene, augite, pigeonite, olivine (occasionally serpentinized), Fe-hornblende and magnesian hornblende, red biotite, magnetite, ilmenite, apatite, and baddeleyite. The composition is tholeiitic, similar to the high-Ti-P basalts of the Serra Geral Formation. Their high contents of K, Rb, Sr and Ba, as well as negative anomalies of Nb and Ta in multielemental diagrams are similar to the ones observed in magmatic rocks from mature arcs or post-collisional environments. The Neoproterozoic basic rocks may be discriminated from the ones belonging to the Cretaceous Serra Geral Formation by their higher contents of alcalis, Cs, U, Th, and by their fractionated REEpatterns, expressed in the La/LuN ratio. The associated granitoids are structural and compositionally compatible with the ones found in post collisional settings, which indicates that the SPL magmatism developed in such environment.

Basic magmatism in Central Spain occur sporadically during a long period of ca. 140 Ma. The scarce data set of incompatible trace element geochemistry and initial isotopic ratios (Sr, Nd) on mantle-derived basic magmatism shaw that subcontinental mantle in Central Spain is markedly heterogeneous. Depleted mantle compositions are not registered and basic magmatism f1uctuate between OIB and BSE values, being crustal involvement (via recycling in mantle sources or by hybridization at emplacement levels) an important contribution ta some basic derivates.

We present the results of a preliminary study on the Santa Eulalia batholith (Alto Alentejo, Portugal). This batholith is made up of two granitic facies, several stocks of basic rocks concentrically disposed and some metasedimentary mega-enclaves. From a geochemical point of view, both granitic facies are peraluminous but difficult to characterize, showing similarities with S- A- and l-granite types. The two granites seem to represent independent magmatic pulses with different source material. The comparison with other granites from the Central Iberian Zone with S-type features, reveals several mineralogical and geochemical differences

Basic magmatism in Central Spain occur sporadically during a long period of ca. 140 Ma. The scarce data set of incompatible trace element geochemistry and initial isotopic ratios (Sr, Nd) on mantle-derived basic magmatism show that subcontinental mantle in Central Spain is markedly heterogeneous. Depleted mantle compositions are not registered and basic magmatism fluctuate between OIB and BSE values, being crustal involvement (via recycling in mantle sources or by hybridization at emplacement levels) an important contribution to some basic derivates

We present the results of a preliminary study on the Santa Eulalia batholith (Alto Alentejo, Portugal). This batholith is made up of two granitic facies, several stocks of basic rocks concentrically disposed and some metasedimentary mega-enclaves. From a geochemical point of view, both granitic facies are peraluminous but difficult to characterize, showing similarities with S- A- and l-granite types. The two granites seem to represent independent magmatic pulses with different source material. The comparison with other granites from the Central Iberian Zone with S-type features, reveals several mineralogical and geochemical differences

El batolito de la Sierra Norte de Sevilla constituye el afloramiento de rocas plutónicas y subvolcánicas más externo del Macizo Ibérico, intruyendo en materiales metasedimentarios y volcá¬nicos de la Zona Surportuguesa. Los nuevos datos de relaciones 87Sr/86Sr de roca total sobre un total de 27 muestras revelan que los granitoides calcoalcalinos con enclaves microgranulares son el pro¬ducto de la interacción entre magmas derivados de una fuente mantélica con afinidades litosféricas y magmas generados por fusión parcial de una corteza continental inferior granulítica en un borde con¬tinental activo. El estudio isotópico de Sr de muestras pertenecientes a zonas de interacción entre mag¬mas básicos y félsicos del BSNS sugiere como el equilibrio isotópico de Sr descrito entre enclave mi-crogranular y granitoide encajante es debido a un mecanismo acoplado de intercambio de cristales y difusión tracer de Sr entre líquidos., The Seville Ranges batholith constitutes the outermost outcrop of plutonic and subvolca-nic rocks of the Iberian Massif, intruding into metasedimentary and volcanic rocks of the South Por¬tuguese Zone. New Sr isotopic data from 27 whole rock samples show that the calc-alkaline granitoids with microgranular enclaves were the product of interaction of magmas derived from a mantle source with lithospheric affinities and magmas developed by partial melting of a granulitic crust in an active continental margin. The Sr isotope study of samples from magmatic interaction zones suggests that the isotopic equilibration of Sr between microgranular enclaves and host calc-alkaline granitoid re¬sulted from mechanisms of crystal exchange and tracer diffusion of Sr in liquids

[Resumen] En este trabajo se describen tres tipos de rocas gabroideas que afloran en el CompIejo de Toledo, atendiendo principalmente a aspectos petrográficos, geoquímicos y a su comparación con otros tipos de rocas básicas hercínicas. El primero de estos grupos está constituido por gabros olivínicos y piroxénicos, denominados tipo La Bastida, que generalmente están en relación con granitoides calcoalcalinos (granitos de Argés), y que varían desde melanoritas olivínicas hasta gabronoritas, observándose en ocasiones un ligero bandeado ígneo. Geoquímicamente presentan una afinidad calcoalcalina normal y definen secuencias en diagramas geoquímicos que pueden explicarse mediante procesos de cristalización fraccionada con acumulaci6n de olivino en los términos más básicos de la serie. Son rocas con caracteres petrológicos y geoquímicos similares a los de rocas básicas de tipo cortlandítico descritas en otros sectores del Hercínico Ibérico (Gredos, Costero-Catalana). Existe un segundo grupo de rocas básicas constituido por gabros anfib61icos, denominados tipo Toledo, que se encuentran, al igual que en el caso anterior, relacionados desde un punto de vista espacio-temporal con la serie de granitoides de Argés. Petrográficamente varían desde gabros (próximos a dioritas) a cuarzogabros anfib6licos, con plagioclasa, anfíbol y biotita como fases fundamentales.Desde un punto de vista geoquímico este grupo presenta características muy contrastadas con respecto a los otros dos grupos gabroideos. pestacan sus altos contenidos en Ti02(1.6-2.2 %), Al20 3 (16-20%), P20 S (0:32-0.88%) ysobre todo en álcalis (Na20+K20 entre 4.7 y 6.3% para un rango de SiG2 de 47-53%). Son también notables sus altos contenidos en Ba y Sr, así como sus bajas relaciones ZrIP20 S• Por estas características se le asigna a este grupo una afinidad de tipo shoshonítico. Son rocas con caracteres geoquímicos en parte similares a los de tipos vaugneríticoshercínicos. Por último, aflora en el Complejo un tercer grupo de gabros, fundamentalmente anfib6licos, aunque también se encuentran variedades anfib61ico-piroxénicas, que aflora exclusivamente en la esquina sureste del mismo y que se ha denominado gabros tipo Villanueva. No están en relaci6n con los granitoides de Argés como ocurría con los otros dos grupos gabroideos. Por el contrario, estas rocas son intrusivas en mármoles dolomíticos preordovícicos en los que provocan un intenso metamorfismo de contacto. petrográficamente se trata de gabros s. s. con plagioclasa, anfíbol, clinopiroxeno y biotita como fases funtamentales. Geoquímicamente presentan características de una serie calcoalcalina, de caracteres similares a los de gabros afines de la Sierra de Guadarrama. [Abstract] The present work deals with petrographical and geochemical aspects of three groups of basics rock that outcrops in the Toledo complexo The relation of these three groups with other hercynian basic rock is also argued. The first group consists of olivine and pyroxene gabbtos (La Bastida type) that usually occurs related to calcalkaline granitoids. Geochemically this group have calcalkaline affinity and its variation trends can be explained by a crystal fractionation mechanism. The chemical characteristics ofLa Bastida gahbros ressembles those of other hercynian zones. The second group of basic rocks consists of amphibole gabbros (Toledo type), that, as La Bastida type, is spatially and age related with calcalkaline granites. Geochemically this group present a shoshonitic affinity because of its high alkalies and associated elements content, and it is chemically similar to sorne variscan vaugneritic rocks. Finally, there is a group of gabbros (Villanueva type) intruded in paleozoic marbIes and unrelated to calcalkaline granites. 1t has calcalkaline affinity, ressembling to the Sierra de Guadarrama gabbros

Transformation of granitic rocks in contact with marly-carbomnate rocks to diorites gabros and peridotites is a normal situation in the Hercinyan of Spain

The basic rocks from the Ayrole area (Montagne Noire, France) are plutonic rocks emplaced as sills between the basement complex (Somail series) and its cover (La Salvetat series). They are comagmatic and belong to a calc alkalic (with some slight tholeitic affinities) differentiated series. The chemical as well as the petrographic studies show : — early ferromagnesian cumulates, transformed by the metamorphism into gabbros with large poikililitic amphiboles, and, — mostly plagioclasic cumulates — some garnet bearing — with hypautomorphic granular texture. After the magmatic stage, these rocks have been chemically modified (lost of CaO and Na₂O, enrichment of K₂O and locally SiO₂) and have undergone catazonal metamorphism., Les roches basiques de l'Ayrole (commune de Fraïsse-sur-Agout, Montagne Noire, France) sont des roches plutoniques disposées en sills antétectoniques au contact de la série du Somail (socle) et de la série de la Salvetat (couverture). Ces roches sont des roches comagmatiques dérivées d'une série calco-alcaline (à faibles affinités tholéitiques) différenciée. L'étude chimique rejoint l'étude microscopique pour distinguer : — des cumulats ferro-magnésiens précoces, que le métamorphisme a transformés en gabbros à grandes amphiboles pœcilitiques ; — des cumulats surtout plagioclasiques à texture grenue hypidiomorphe ; certaines de ces roches contiennent du grenat. Postérieurement à ce stade magmatique, ces roches ont été modifiées (départ de CaO, Na₂O, apport de K₂O, silicification éventuelle) et ont subi un métamorphisme catazonal., Demange Michel, Frignet Bernard. Les roches basiques de l'Ayrole (commune de Fraïsse-sur-Agout, Hérault), massif de l'Agout, Montagne Noire. Étude chimique. In: Bulletin de la Société française de Minéralogie et de Cristallographie, volume 100, 2, 1977. pp. 114-122.

The Millas Massif is located north-west of Prades, in the Eastern Pyrenees, and covers the western sector of the granite massif of Millas, which is part of the Pyrenean axial zone. This massif is limited to the North by the North Pyrenean fault; it is in contact in the South and the West with the Ordovician shales of Jujols. The cartographic study, supported by petrography and geochemistry, was aimed at establishing the geological map of the massif, showing: the zoned megastructure of the various (very dominant) granites; the arrangement of large basic masses that may contain rare ultramafic clusters; the existence of acid-basic associations, related or not, to the proximity of important basic masses; the presence of gneiss and metasedimentary levels in septa. The petrographic, mineralogical and geochemical studies made it possible to characterize these various units and to approach the question of their origin and their mutual relations: genetic relations between the two principal granites and hypotheses on their formation; case of the "intermediate facies" between these two principal granites; origin of basic rocks and associated ultramafic clusters; problem of the existence, or not of a cogeneration between acidic and basic formations; case of granodioritic facies; nature of gneisses in septa, relations with granites, comparison with Canigou gneisses. The case of the transformation of granite into sericiteit is also treated. The model established is compared with the work done on the Massif de Quérigut. The deposit of chlorite and talc Caillau: It is located in the Pyrenees-Orientales, on the border with the department of Aude. It is located at the eastern end of the Massif de Quérigut, in an area where granite and metasediments are in tectonic contact. Several types of rocks (granite, shale, corneal, carbonate levels) are affected to varying degrees by magnesian metasomatism that causes mineralogical and geochemical changes that can lead to the formation of chlorite (very dominant) and talc rocks. It is shown that the mobility of chemical elements depends on the nature of the starting minerals and the stage of transformation achieved, Le Massif de Millas : Le terrain étudié est situé au Nord-Ouest de Prades, dans les Pyrénées Orientales, et couvre le secteur occidental du massif granitique de Millas, qui fait partie de la zone axiale pyrénéenne. Ce massif est limité au Nord par la faille nord-pyrénéenne ; il est en contact au Sud et à l'Ouest avec les schistes ordoviciens de Jujols. L'étude cartographique, appuyée par la pétrographie et par la géochimie, a eu pour but l'établissement de la carte géologique du massif, montrant : la mégastructure zonée des divers granites (très dominants) ; la disposition des masses basiques importantes pouvant renfermer de rares amas ultrabasiques ; l'existence d'associations acide-basique liées, ou non, à la proximité de masses basiques importantes ; la présence de gneiss et de niveaux métasédimentaires en septa. Les études pétrographique, minéralogique et géochimique ont permis de caractériser ces diverses unités et d'aborder la question de leur origine et de leurs relations mutuelles : relations génétiques entre les deux principaux granites et hypothèses sur leur formation ; cas des "facies intermédiaires" entre ces deux granites principaux ; origine des roches basiques et des amas ultrabasiques associés ; problème de l'existence, ou non d'un cogénétisme entre formations acides et basiques ; cas des faciès granodioritiques ; nature des gneiss en septa, relations avec les granites, comparaison avec les gneiss du Canigou. On traite également le cas de la transformation du granite en séricitite. Le modèle établi est comparé avec les travaux effectués sur le Massif de Quérigut.Le gisement de chlorite et talc de Caillau : Il est situé dans les Pyrénées-Orientales, à la limite avec le département de l'Aude. Il se trouve à l'extrémité est du Massif de Quérigut, dans un secteur où le granite et des métasédiments sont en contact tectonique. Plusieurs types de roches (granite, schistes, cornéennes, niveaux carbonatés) sont affectés à des degrés divers par une métasomatose magnésienne qui provoque des modifications minéralogiques et géochimiques pouvant conduire à la formation de roches à chlorite (très dominante) et talc. On montre que la mobilité des éléments chimiques dépend de la nature des minéraux de départ et du stade de transformation atteint.