Open-system magma chamber process in the Freetown Complex of Sierra Leone: evidence from Zone 3
Article Abstract:
Sierra Leone's Freetown layered complex is a crescent-shaped intrusion dating from the Jurassic opening of the middle Atlantic Ocean. The complex has four zones consisting of troctolite, gabbro, olivine gabbro, gabbronorite and anorthosite. Previous studies have suggested that the complex solidified in situ from a parental magma characterized by constant mineral compositions. However, electron microprobe analyses of mega-unit Zone 3 suggest the existence of cryptic variation in the complex.
Publication Name: Geological Magazine
Subject: Earth sciences
ISSN: 0016-7568
Year: 1995
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Pterosaur fossils from the Cretaceous of Chile: evidence for a pterosaur colony on an inland desert plain
Article Abstract:
An archeological investigation of sandstone and conglomerate beds in the Andes desert sediments of northern Chile reveal the presence of bones of pterosaur. The sediments display indications of a flood which could have singularly destroyed a vast population of pterosaurs in the Andes. Mass destruction of these flying animals suggests the absence of adequate food for the whole population and also implies that the pterosaurs were not totally incapable of sustaining themselves on land.
Publication Name: Geological Magazine
Subject: Earth sciences
ISSN: 0016-7568
Year: 1995
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Regnosaurus northamptoni, a stegosaurian dinosaur from the Lower Cretaceous of southern England
Article Abstract:
A study conducted on Regnosaurus northamptoni Mantell, a partial right mandible of a dinosaur from the Lower Cretaceous of southern England, shows that it could be a primitive stegosaur. Researchers previously thought that it was an ankylosaur or a sauropod. Comparisons of Regnosaurus and Huayangosaurus shows similarities between the two and so these two genera could be considered as sister taxa. The evolutionary findings and biogeography of stegosaur are discussed.
Publication Name: Geological Magazine
Subject: Earth sciences
ISSN: 0016-7568
Year: 1995
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