Abstract: Abstract Carbonates from the Holkerian (Lower Carboniferous) Concretionary Beds of the Bristol area, the Upper Jurassic-Lower Cretaceous Purbeck Limestone Group of southern England and the Aptian Pre-salt succession of the South Atlantic exhibit spherulites and a range of related crystal shrubs and fibrous crusts. Some of these fabrics are associated with framework microbialites, including thrombolites, that developed under varying degrees of non-marine influence. Brackish or fresh waters affected the Holkerian and Purbeckian microbialites, alt...
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Topics: 
Paleontology