1/2/2023 0 Comments Oolite growth rate diagramBedding parallel dark insoluble residue/organic matter, lenticular quartz grains, and angular bioclasts are observed frequently. The rock shows discontinuous, but bedding parallel quartz rich (<40%) and mud-rich layers. These interlayers are found without any break in sedimentation and resulted by increased influx of bioclasts of bivalves and echinoderms. The Gypsiferous Shale Member is composed of bioclastic calcareous very fine silt interspersed with bioclastic arenaceous packstone and occasional arenaceous peloidal bioclastic packstone. (A) Lodai section (B) Fakirwari section (C) Jumara section (D) Jara dome Tr. Lithologs of the three studied sections and position of geochemical samples. The Jumara section (JMS) is located at about 20 km northeast of Matanomadh close to the Jumara village and exposes the DOM and basal part of the Katrol Formation ( Fig. The Fakirwari section (FWS) is located at about 6 km south of Bhuj, along the road to Mundra, exposing the DOM and other members of the Chari Formation ( Fig. The rocks are exposed close to the road 3 km south of Lodai, over a lateral distance of 320 m, showing the occurrences of the Gypsiferous Shale, Dhosa Sandstone, and DOMs of the Chari Formation and basal part of the Katrol Formation ( Fig. The Lodai section (LDS) is a composite section located at northeast of Bhuj in the Habo dome ( Fig. Among various exposures examined, three sections located in Lodai, Fakirwara, and Jumara that contain condensed sections of the DOM are discussed in this paper. This surface is a chronological boundary between Callovian-Oxfordian ( Fürsich et al., 2001) and also a transgressive systems tract surface ( Pandey et al., 2009). The DOM rests over the Dhosa Sandstone Member with a distinct erosional/nondepositional surface. Good exposures are found in Jara, Jumara, Keera, Jhura, and Habo domes/areas, located between southeast of Lakhpat and east of Bhuj ( Fig. It is easily recognizable in the field by its red-colored, well-cemented cap rock and massive amorphous iron crusts at top. D Calcareous algae, Carboniferous, corals, Dinantian, foraminifera, reefs, thrombolites.The DOM is exposed for about 100 km along its strike direction in the Kachchh mainland. The occurrence of these reefs cannot be attributed to any single environmental factor but probably resulted from an unusual combination of favourable circumstances. Rapid sedimentation and subsidence resulted in reefs with near vertical sides, but little topographic expression on the sea‐floor during growth. During the later stages of reef growth, Syringopora became less common and its place in the reef was taken by upright, branching growths of solenoporoid algae. Thrombolites also assisted in the establishment of bindstone textures. Encrusting organisms, dominantly the supposed foraminifcr Aphralysia, colonised sediment and corallite surfaces leading to the development of a rigid framework. Reefs were initiated by the attachment of numerous Syringopora colonies to a firm substrate. They occur in the Red Hill Oolite, part of the Carboniferous Limestone succession in the Furness area of northwest England. This contribution describes apparently unique structures containing abundant framebuilding organisms interpreted as true reefs. Most carbonate buildups of Dinantian age are mud‐mounds lacking direct evidence of abundant framework organisms. Development of algal‐foraminiferal‐coral reefs in the Lower Carboniferous of Furness, northwest England Development of algal‐foraminiferal‐coral reefs in the Lower Carboniferous of Furness, northwest.
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