Morphology and genesis of nodular phosphates in the Cenomanian Glauconitic Marl of south‐east England

作者: W. JAMES KENNEDY , ROBERT E. GARRISON

DOI: 10.1111/J.1502-3931.1975.TB00940.X

关键词:

摘要: Phosphatic nodules are abundant in the Glauconitic Marl (Cretaceous, Cenomanian) of south-east England, particularly where sequence is condensed. Some derived from underlying Upper Greensand, and phosphatic fossil fragments, moulds, calcareous concretions. Concretions particular show signs a complex history multiple phases boring, encrustation, phosphatisation, glauconitisation. Phosphate glauconite both replacements after fine-grained carbonate sediment cement. The majority phosphates whole fragmentary moulds fossils. origin theses involved: (1) infilling shells, (2) burial, (3) prefossilisation-cementation infillings. probably by high magnesian calcite, (4) dissolution aragonitic shell material, (5) disinterment exposure on sea floor, followed (6) phosphatisation. boring. enerustation various organisms, sometimes Many bear evidence several cycles cementation, exposure, mineralisation, boring enerustation. The closest Recent analogues to appear be crust forming today off coast southern California. features described processes inferred occurrences have been widespread nodular facies.

参考文章(31)
, Alfred John Jukes Browne, William. Hill, The Cretaceous rocks of Britain Printed for H. M. Stationery off., by Wyman and sons, limited,. ,vol. 1, ,(1900) , 10.5962/BHL.TITLE.115398
G.I. Bushinski, On Shallow Water Origin of Phosphorite Sediments Developments in sedimentology. ,vol. 1, pp. 62- 70 ,(1964) , 10.1016/S0070-4571(08)70468-0
F.A. Middlemiss, R.G. Bromley, Field meeting on the Lower Greensand and Chalk in the Isle of Wight Proceedings of the Geologists' Association. ,vol. 73, pp. 449- 453 ,(1962) , 10.1016/S0016-7878(62)80033-9
Egon T. Degens, Geochemistry of Sediments Soil Science. ,vol. 100, pp. 225- ,(1965) , 10.1097/00010694-196509000-00025
Herman H. Zumpe, Microstructures in Cenomanian Glauconite from the Isle of Wight, England Mineralogical Magazine. ,vol. 38, pp. 215- 224 ,(1971) , 10.1180/MINMAG.1971.038.294.11
J. D. Milliman, Submarine lithification of carbonate sediments. Science. ,vol. 153, pp. 994- 997 ,(1966) , 10.1126/SCIENCE.153.3739.994
Richard Granville Bromley, On some ichnotaxa in hard substrates, with a redefinition of Trypanites Mägdefrau Palaeontologische Zeitschrift. ,vol. 46, pp. 93- 98 ,(1972) , 10.1007/BF02989555