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Por Fabrício Caxito Estamos acostumados a pensar no nosso planeta como uma bola de gude azul manchada por nuvens brancas flutuando no espaço, como nas imagens fantásticas da era da exploração espacial. Mas a Terra nem sempre teve esse aspecto que reconhecemos como tão amigável. Em seus 4,5 bilhões de anos de idade, nosso planetaContinuar lendo “A dança entre a vida e a Terra”

The effects of mountain belts in supporting the conditions for the development of complex life forms in adjacent basins are warmly debated today. In this paper, MOBILE Project researchers show that, while mountains might provide oxygen and nutrients, if a sea basin becomes surrounded by mountains and completely restricted, this effect might become damaging toContinuar lendo “Goldilocks at the dawn of complex life: mountains might have damaged Ediacaran–Cambrian ecosystems and prompted an early Cambrian greenhouse world”

Island arcs are magmatic arcs formed when oceanic tectonic plates slide below one another in subduction zone settings, just like in the present-day southwestern Pacific Ocean, as in Japan and Indonesia. Island arcs are important tectonic components to understand the evolution of the planet and consequently the continents and oceans that existed in the past.Continuar lendo “Tonian island arc remnants in the northern Ribeira orogen of Western Gondwana: The Caxixe batholith (Espírito Santo, SE Brazil) – (Santiago et al. 2020)”

The Ordovician radiation was one of the most significant diversifications of marine life and it coincides with a time of intense orogenic activity. The geographic distribution of 6576 appearances of Ordovician genera was investigated, in order to understand the relation among biodiversity and the geological context (foreland basins, transition zones, and carbonates platforms). The resultContinuar lendo “Qual a relação entre biodiversidade e o ambiente tectônico? What is the relation between biodiversity and the geological setting?”

Rhander Taufner Durante o espalhamento da crosta oceânica gabroica nas dorsais meso-oceânicas lentas e ultra-lentas, as zonas de cisalhamento em grande escala crustal acomodam a maioria dos movimentos das placas em falhas de descolamento. O fluxo de material fundido e fluidos quentes em profundidade ao longo dessas falhas produz fontes hidrotermais no assoalho oceânico, nasContinuar lendo “#thinsectionthursday”

As disjunções colunares são fraturamentos prismáticos que ocorrem em basaltos ou em outros tipos de rochas ígneas e são resultados do processo de resfriamento do magma. Devido à diferença de temperatura entre a lava e a rocha encaixante (ou ar), ocorre um resfriamento acelerado, de fora para dentro do derrame. Esse resfriamento é responsável pelaContinuar lendo “Colunas e disjunções prismáticas em lavas basálticas”

Graphite is a natural form of carbon crystallized under lower pressures and temperatures than those needed to stabilize diamond. It is a very important mineral resource with applications in the steel industry, as a lubricant, in refractories, paints, oven and brake linings, brushes, batteries, electrodes, pencils, explosives, magnetic tapes, fertilizers and in the making ofContinuar lendo “Graphite deposits, burial of organic carbon and the first appearance of complex life forms / Depósitos de grafita, soterramento de carbono orgânico e a primeira aparição das formas de vida complexas”

PLAGIOGRANITO – um componente muito importante do fundo do oceano! Do you know what plagiogranite is? This very special type of granite is composed of plagioclase with small amounts of quartz and ferromagnesian minerals. They were long recognized as very important parts of ophiolitic complexes, rocks that represent ancient pieces of ocean floor that areContinuar lendo “PLAGIOGRANITE – a very important component of the ocean floor!”