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Middle Jurassic (Callovian) strata of Tuwaiq Mountain Limestone Formation, central Saudi Arabia are composed of thin- to thick-bedded, grainy and muddy limestones and dolostones with various skeletal and nonskeletal components. Facies analysis documents low- to high-energy environments, including lagoon, back reef, reef framework, fore-reef and intra-shelf basin lithofacies associations. Because of the narrow lateral distribution of facies and the presence of distinctive fossils, the depositional system likely represents an open marine shelf. Two third-order depositional sequences can be distinguished in the stratigraphic measured section. Transgressive sequences show deepening-upward trends, in which shallow water (lagoonal and back reef) facies are overlain by deeper-water (fore-reef and intra-shelf basin) facies. Regressive sequences show shallowing-upward trends in which deep-water facies are overlain by shallow-water facies. Most sequence boundaries in the study area are of the nonerosional (SB2) type. Correlation of depositional sequences in the studied section reveals that relatively shallow marine conditions predominated in the area. [ABSTRACT FROM AUTHOR]

The properties of colloidal nanoparticles are the key parameters in the fabrication of inexpensive solar cells based on the solution methods. In this study, Different nanostructures of CuInS 2 (CIS) were successfully synthesized by a heating-up facile polyol-based method in which, polyols including diethylene glycol (DEG), ethylene glycol (EG), and glycerol (Gly) were chosen as both the solvent and the reductant. It is found that not only the indium precursor type but also the polyol solvent are greatly effective on the size, morphology and crystal phase of this sulfide ternary composition. Briefly, the heating-up synthesis using In(acac) 3 in DEG and Gly media, created nano-sized particles that arranged in a wurtzite crystalline structure. Resulted CIS particles from other indium salts are not suitable for making nanoparticle-based inks, since the micron-sized agglomerated particles are obtained which lack proper dispersion behavior for making inks. Image 1 • Different nanostructures of CuInS 2 were successfully synthesized by a heating-up facile polyol-based method. • The polyol solvent and indium salt have greatly effective on the size, morphology and crystal phase of CuInS 2 NPs. • Nano-sized particles are obtained only by the use of In(acac) 3 in diethylene glycol and glycerol solvents. [ABSTRACT FROM AUTHOR]

In order to document the microfacies and diagenesis of the reefal limestone in the uppermost part of the Callovian Tuwaiq Mountain Limestone Formation at Khashm Al-Qaddiyah area, central Saudi Arabia, scleractinian corals and rock samples were collected and thin sections were prepared. Coral framestone, coral floatstone, pelloidal packstone, bioclastic packstone, bioclastic wacke/packstone, algal wackestone and bioclastic foraminiferal wacke/packstone were the recorded microfacies types. Cementation, recrystallization, silicification and dolomitization are the main diagenetic alterations affected the aragonitic skeletons of scleractinian corals. All coral skeletons were recrystallized, while some ones were dolomitized and silicified. Microfacies types, as well as the fossil content of sclearctinian corals, bivalves, gastropods, brachiopods and foraminifera indicated a deposition in environments ranging from shelf lagoon with open circulation in quiet water below wave base to shallow reef flank and organic build up for the uppermost reefal part of the Tuwaiq Formation in the study area. [ABSTRACT FROM AUTHOR]