Keywords : Formation


Authigenic Minerals and Diagenesis in The Clastic Sediments of The Ghar Formation South and Southeast Iraq.

Ali I. Al-Juboury Jamal S. Al-GhrearMohammad A. Al-Rubaii

Iraqi National Journal of Earth Sciences, 2003, Volume 3, Issue 1, Pages 1-21

Study of clay minerals (Kaolinite,Iillite and Illite-Smectite mixed layers) in the clastic sediments of the Ghar Formation (Upper Oligocene-Lower Miocene) is the main indicator for the variation of the pore waters responsible for the eodiagenetic processes affecting on
these sediments. Variation of these clay minerals are used also to distinguish the sedimentary environments of the Ghar Formation as transitional environment from fluvial into marine. The genetic relations of these clay minerals and their semi quantitative proportions by XRD and SEM are used also to distinguish the authigenic minerals and their paragenetic sequence.
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Non Marine Molluscs in the Injana Formation, Kand Anticline, NW of Mosul / Iraq

Basam M. Al-Dewachi; Mumtaz A. Amin

Iraqi National Journal of Earth Sciences, 2003, Volume 3, Issue 1, Pages 1-10

Monotypic shell beds of molluscan skeletal sand are contained in the non-marine, fluvial sequence of Injana Formation of Upper Miocene age-Kand Anticline, as yet undescribed previously. These carbonate beds are characterised only by abundant pelecypod, oyster with scarce and opportunists gastropods and smooth-shelled ostracods. This faunal assemblage is consignable with non-marine low salinity euryhaline fresh, brackish water. The sudden change in their composition and distribution has been influence by salinity variation. The exclusion of normal marine-stenohaline fauna point to their deposition in non-marine setting including interchannel lake initiated on distal floodplain and/or river dominated bay esturay, or fan delta lake-lagoon.