On the Origin of Sedimentary Aragonite Needles of the Great Bahama Bank

摘要: Field evidence on the origin of sedimentary aragonite needles indicates that may be derived from certain algal carbonates. Determinations were made relative $$O^{18}$$/$$O^{16}$$ and $$C^{13}$$/C$$^12$$ ratios various aragonitic carbonates, including needle-secreting algae, oolites, grapestones, Great Bahama Bank area. The range isotopic algae was different oolites grapestones. isotope for both carbon oxygen lie in median carbonates outside This would indicate are primarily organic origin. possibility data compatible with their being inorganic is evaluated.