|mhorn||Дата: Sunday, 17.02.2013, 23:09 | Сообщение # 1|
|Pandey D.K., Choudhary S., Bahadur T., Swami N., Poonia D., Sha J. (2012) A review of the Lower – lowermost Upper Jurassic facies and stratigraphy of the Jaisalmer Basin, western Rajasthan, India // Volumina Jurassica. Vol.10, no.1. P. 61–82. |
The Lower – lowermost Upper Jurassic (up to Oxfordian) sedimentary succession of the Jaisalmer Basin on the Rajasthan Shelf is characterized by gradual lateral and rapid temporal facies variations, the existence of condensed sequences in certain horizons, and rich and highly diverse faunal contents. Lithostratigraphically, these Jurassic rocks of the basin have been grouped into the Lathi and Jaisalmer formations and the lower part of the Baisakhi Formation. The facies consist of (i) cross-bedded medium- to coarse-grained sandstone, (ii) cross-bedded to thinly laminated silt to fine-grained sandstone, (iii) silty marl, (iv) calcareous mud- to grainstone and sandy rudstone, (v) thinly laminated carbonaceous shale and (vi) conglomerate. These represent fluvial, floodplain, lacustrine, protected marginal marine, and shoreface to shelf environments. There are several marker units, which allow the making of intrabasinal lithostratigraphic correlations; however, a lack of knowledge of the detailed stratigraphic successions within individual lithostratigraphic units makes difficult a precise intra-basinal stratigraphic correlation. The present review provides a summary of the lithostratigraphy established by previous workers on the Lower – lowermost Upper Jurassic (up to Oxfordian) rocks of the Jaisalmer Basin, incorporating additional data, with a detailed stratigraphic succession within each lithostratigraphic unit, and more faunal elements recently.
Middle Jurassic - Lower Cretaceous ammonites & aptychi