28 documents found, page 1 of 3
Detailed in-depth mapping of the world largest anorthositic complex: Magnetic a...
Merino-Martínez, E.; Rey-Moral, Carmen; Machadinho, Ana; Carvalho, João; Represas, Patricia; García-Lobón, J. L.; Feria, María CarmenABSTRACT: The Kunene Complex (KC) represents a very large Mesoproterozoic igneous body, mainly composed of anorthosites and gabbroic rocks that extends from SW Angola to NW Namibia (outcropping 18,000 km2 , NE-SW trend, and ca. 350 km long and up to 50 km wide). Little is known about its structure at depth. Here, we use recently acquired aerogeophysical data to accurately determine its hidden extent and to unra...
Age dependent variation of the magnetic fabric of dike swarms and implications ...
Moreira, Mário; Mata, João; Madeira, José; Represas, Patricia; Martins, SofiaABSTRACT: Magnetic fabric analysis of dikes is a powerful technique when assessing magma transfer processes. This study presents an integrated analysis combining magnetic susceptibility and anisotropy of magnetic susceptibility, magnetic mineralogy, geochemistry and new 40Ar/39 Ar dating of dikes intruding formations ranging from the Lower Cretaceous to the Miocene on the island of Maio, in the Cabo Verde archi...
Modelización magnética del Complejo de Cunene (SW Angola) [Resumo]
Mochales, Tania; Merino-Martínez, E.; Rey-Moral, Carmen; Machadinho, Ana; Carvalho, João; Represas, Patricia; García-Lobón, J. L.; Feria, María CarmenRESUMEN: El Complejo de Cunene (CC) representa un extenso macizo ígneo mesoproterozoico compuesto por rocas anortosíticas, gabroicas y ácidas contemporáneas, que aflora 18.000 km2 en dirección NNE-SSW desde el SW de Angola al NW de Namibia. Se han interpretado y modelizado en 2,5/3D los datos aerogeofísicos obtenidos en el proyecto PLANAGEO para investigar los límites no expuestos del CC, reconstruyendo la estr...
Geophysical characterization of the Cercal Paleozoic structure, Iberian Pyrite ...
Feitoza, L. M.; Carvalho, João; Represas, Patricia; Ramalho, Elsa; Sousa, Pedro; Matos, João Xavier; Albardeiro, Luís; Morais, IgorABSTRACT: The Cercal Volcano-Sedimentary Complex (Cercal VSC) structure is the westernmost sector of the Iberian Pyrite Belt (IPB) giant metallogenic province and was explored since Roman times for volcanogenic massive sulphides (VMS) and Fe–Mn (Ba) deposits. However, presently only a single deposit is known, the Salgadinho Cu-Ag-Au stockwork/disseminated deposit. Nevertheless, according to several mining compa...
Modelización magnética del Complejo de Cunene (SW Angola) [Resumo]
Mochales, Tania; Merino-Martínez, E.; Rey-Moral, Carmen; Machadinho, Ana; Carvalho, João; Represas, Patricia; García-Lobón, J. L.; Feria, María CarmenRESUMEN: El Complejo de Cunene (CC) representa un extenso macizo ígneo mesoproterozoico compuesto por rocas anortosíticas, gabroicas y ácidas contemporáneas, que aflora 18.000 km2 en dirección NNE-SSW desde el SW de Angola al NW de Namibia. Se han interpretado y modelizado en 2,5/3D los datos aerogeofísicos obtenidos en el proyecto PLANAGEO para investigar los límites no expuestos del CC, reconstruyendo la estr...
Geophysical characterization of the Cercal Paleozoic structure, Iberian Pyrite ...
Feitoza, L. M.; Carvalho, João; Represas, Patricia; Ramalho, Elsa; Sousa, Pedro; Matos, João Xavier; Albardeiro, Luís; Morais, IgorABSTRACT: The Cercal Volcano-Sedimentary Complex (Cercal VSC) structure is the westernmost sector of the Iberian Pyrite Belt (IPB) giant metallogenic province and was explored since Roman times for volcanogenic massive sulphides (VMS) and Fe–Mn (Ba) deposits. However, presently only a single deposit is known, the Salgadinho Cu-Ag-Au stockwork/disseminated deposit. Nevertheless, according to several mining compa...
Late Cretaceous magmatism offshore the central West Iberian Margin
Pereira, Ricardo; Escada, Cláudia; Represas, Patricia; Mata, João; Rosas, Filipe M.; Ramalho, R.S.SUMÁRIO: A análise de dados de reflexão sísmica, combinados com modelos de inversão de dados potenciais (gravimetria-magnética), revela a presença, natureza e detalhes de um sistema magmático localizado no offshore da Margem Oeste Ibérica. As evidências incluem o vulcão de Fontanelas com escoadas de lavas associadas, a Intrusão do Esporão da Estremadura, e diversos complexos de soleiras, enquanto manifestações ...
New insights on the ultramafic intrusions surrounding the Kunene Anorthosite Co...
Represas, Patricia; Sousa, Pedro; Morais, Igor; Cordeiro, Domingos; Carvalho, João; Batista, Maria Joao; Dito, Manuel; Llorente, J.; Marques, FábioABSTRACT: The Kunene Anorthosite Complex (KAC), located in SW Angola, is one of the largest anorthosite structures in the world. Dating from the Mesoproterozoic, its installation process is still not clear. Several mafic and ultramafic outcrops can be found surrounding the KAC. Once considered related with its emplacement, the study of these bodies may help us understand the history of this unique geological fe...
Metallogenetic potencial of the Paleoproterozoic mafic-ultramafic Hamutenha int...
Morais, Igor; Batista, Maria Joao; Represas, Patricia; Albardeiro, Luís; Prazeres, Cátia; Plastov, José Manuel; Sousa, João Carlo; Bravo, PauloABSTRACT: In the SW sector of the Angolan shield occur the Kunene Anorthositic Complex (KAC), one of the most remarkable magmatic anorthositic suites worldwide. The KAC is considered a long-lived magmatic system that operated in the area intermittently during the Mesoproterozoic (1450 ± 2 Ma to 1371 ± 2.5 Ma). Smaller mafic-ultramafic intrusive bodies ranging in composition from dunite to harzbugite, pyroxenite...
Late Cretaceous post-rift magma emplacement offshore the West Iberian Margin [A...
Pereira, Ricardo; Escada, Cláudia; Represas, Patricia; Ramalho, R.S.; Mata, João; Rosas, Filipe M.ABSTRACT: The West Iberian Margin is a prime example of a magma-poor hyperextended continental margin. However, the margin is punctuated by three discrete Mesozoic magmatic events, from which the last, occurring 20-40 M.a. after complete lithospheric breakup of the Iberia-Newfoundland conjugate margin, is related to the late Cretaceous Atlantic Alkaline Province. It is characterised onshore by multiple outcropp...