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The metasedimentary Lujiapuzi Formation crops out along the northeastern margin of the North China Craton, close to the Yan‐Liao Rift. The age and tectonic setting of the formation, and its relationship with the Yan‐Liao Rift are currently unclear. Here we present detrital zircon U‐Pb ages, and Hf isotopic and geochemical data for the Lujiapuzi Formation to constrain the timing of deposition, the provenance of the formation, and the regional stratigraphy relationship. Zircon U‐Pb dating constrains the timing of deposition of the Lujiapuzi Formation to younger than 1780 Ma, and indicates that most grains were sourced from the Longgang Block and the Paleoproterozoic Liao‐Ji Belt. Detailed field investigations and a correlation of the regional stratigraphy reveal that much of the Lujiapuzi Formation is equivalent to the Tuanshanzi Formation in the Yan‐Liao Rift; the lower section may represent the earliest sediments deposited within the Fanhe Basin. Based on these results and the findings of previous studies, we suggest that the base of the Changcheng System has an age of 1.80 Ga. Zircon Hf isotopic data indicate that the main period of crustal growth along the northeastern margin of the North China Craton occurred at 3.2–2.5 Ga, with a peak at 2.9–2.7 Ga. [ABSTRACT FROM AUTHOR]

Using analyses of the lithology, sequences, paleoenvironment, and tectonic setting, the depositional system of the Carboniferous Huanglong Formation in the eastern Sichuan Basin was identified. The lithological characteristics of the Lower Member, Middle Member, and Upper Member were analyzed and classified. Before the use of carbon, oxygen, and strontium isotopes in the analysis, all of the geochemical data were tested for validity. On the basis of the Z values obtained from carbon and oxygen isotopes, the paleoenvironments of the three members were elucidated. Lower Member was dominantly an enclosed marine environment with intense evaporation and little freshwater input into the sea. Middle Member developed in a semi-enclosed to normal marine environment with many rivers. Upper Member was formed in a normal marine environment. The east Sichuan Basin was enclosed by paleouplifts before the deposition of the Huanglong Formation, forming a relatively enclosed depositional setting. Paleogullies developed in the Silurian strata that underlie the Carboniferous rocks; these paleogullies can be identified. On the basis of a comprehensive analysis, we propose that the Huanglong Formation developed in a platform system. Four microfacies were identified: supratidal flat, dolostone flat, grain shoal, and shelf microfacies. The high-permeability and high-porosity characteristics of the grain shoal microfacies are favorable for hydrocarbon accumulation, while the supratidal flat and shelf microfacies developed very few high-quality reservoirs. The paleogullies, in which increased amounts of grain shoal microfacies developed, controlled the distribution of high-quality reservoirs. [ABSTRACT FROM AUTHOR]

The Upper Permian Dalan Formation and the Lower Triassic Kangan Formation in the Persian Gulf area are mainly composed of shallow marine facies limestone and dolomite. Two subsurface-cored intervals were investigated in order to understand the original mineralogy and paleoceanic conditions. The decreasing trend of Sr concentration in these deposits shows that aragonite was precipitated during the Late Permian and then gradually changed to calcite toward the Permian-Triassic boundary (PTB). The dissolution rate of aragonite decreased from 60 m below the PTB toward the boundary, with the only exception at 10 m below the Permian-Triassic Boundary (PTB) due to the Permian-Triassic unconformity in this region. The increasing trend of Mg/Ca ratio in a global scale at the end-Permian time shows that the interpreted variation of mineralogy does not result from the change of this ratio. The increasing pCO2 and decreasing pH are considered to be the main controlling factors. The increase of Ca2+ at the end-Permian time due to the input of meteoric waters is too little to fully compensate this effect A local maximum of the Si content just at the PTB confirms the input of runoff waters. [ABSTRACT FROM AUTHOR]

The article discusses a research concerning shale distribution and geochemistry of 4th member of Shahejie Formation in Liaohe Western Depression in Bohai Bay Basin, China and examines its shale oil accumulation geological conditions. Details about the shale sedimentary and distribution in the area, shale thickness, and types and abundance of organic matter are noted. Also provided is information on the lacustrine shale oil accumulation of the shales.

The article focuses on findings of a study on geochemical characteristics and geological significance of picritic rocks in Permian Tiaohu Formation from Santanghu Basin, Xinjiang of China. Topics include magmatic activity of Permian in Santanghu Basin; characteristics of picritic rocks, such as SiO2 amount of picritic rocks; and voluminous postcollisional granitoids and Armantai and Karamaili suture zone formation age.

The article reports on the meganodular limestone in South China. It highlights time-specific facies-based three-dimensional network structure of the Upper Ordovician Pagoda Formation in the country. It also outlines the basis of the analysis on the formation which involves the use of geochemical, paleontological and sedimentological information.

The article discusses a research concerning geochemistry and petrography of clastic deposits from the Late Paleozoic Shihezi Formation in Eastern Ordos Basin in China, along with the implications for provenance and tectonic setting. Topics include the significance of provenance studies in reconstructing paleo-drainage systems, mineralogy and petrology of sandstones, and major, trace, and rare earth element compositions of sandstones from the formation.