Geochemical and geological characteristics of Permian Lucaogou Formation shale of the well Ji174, Jimusar Sag, Junggar Basin, China: Implications for shale oil exploration

Abundant shale oil resources were recently found in the organic-rich Permian Lucaogou (P2l) Formation shale, Jimusar Sag, Junggar Basin. Although some scholars have conducted some researches on the basic geochemical characteristics of the Lucaogou Formation shale, it is not enough to effectively guide the shale oil exploration in the area. This is because during the exploration process of shale oil, besides the basic geochemical characteristics of shale, its mineral composition, physical properties, and oil-bearing characteristics are all very important evaluation parameters. To systematically evaluate the favourable shale oil exploration sections in the Lucaogou Formation, 265 pieces of shale cores were sampled from well Ji174 in this study. Besides the basic geochemical characteristics of the 265 pieces of cores, the mineralogical, petrophysical, and oil-bearing characteristics were also analysed. Results show that the shale has abundant organic matter (average total organic carbon 3.51%, average petroleum generation potential 15.67 mg/g), dominated by Type II1 and Type II2 kerogen, and has entered the early-mature to mature stage. The Upper Member of the Lucaogou Formation has relatively higher organic matter and organic matter type is relatively more oil prone compared to the Lower Member; however, organic matter thermal maturity is lower. The P2l Formation shale is characterized by high carbonate minerals and low clay minerals, and when considering mineralogical brittleness, both the Upper and Lower members are ideally fracturable in shale oil development. The P2l Formation shale has a wide porosity range (1.1–13.9%), and the Lower Member’s porosity is slightly greater. The inversion of shale porosity in the P2l Formation is controlled by the differentiated mineral composition. The oil saturation index values of the Lower Member shale are significantly greater than the Upper Member shale. From the above, the Lower Member of the P2l Formation shale is ideally suited and has greater shale oil potential in the Jimusar Sag, Junggar Basin, especially in the depth intervals of 3,255–3,272, 3,282–3,298, and 3,317–3,334 m in the well Ji174.

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Geochronology and geochemistry of early-middle Silurian intrusive rocks in the Lanzhou–Baiyin regions, eastern part of Qilian Block, NW China: Source and tectonic implications

The Qilian Block is one of many continental blocks involved in the early Paleozoic orogenesis of the Central China Orogen, which experienced complex interaction with adjacent blocks and orogens. In this study, we present zircon U–Pb–Hf isotopic, whole-rock elemental, and Sr–Nd isotopic data of the early-middle Silurian intrusive rocks in the Lanzhou–Baiyin regions, eastern part of the Qilian Block, to constrain their source and tectonic settings. The Houchangchuan granodiorite and Shichuan monzogranite were emplaced at ca. 437 Ma and ca. 428 Ma, respectively. These granitoids are peraluminous (A/CNK = 1.1–1.3), enriched in LREEs and LILEs (Rb, Th, U, Pb), depleted in HFSEs (Nb, Ta) with negative Eu and Sr anomalies, and have relatively high whole-rock εNd(t), −4.3 to −2.1, and zircon εHf(t), −10.9 to 1.1, values. The Shichuan monzonite is characterized by intermediate SiO2, metaluminous (A/CNK = ~0.8), and high LREEs fractionation with LILEs (Th, U, Pb) enrichment and HFSEs (Nb, Ta) depletion. We suggest the Houchangchuan granodiorite and Shichuan monzogranite were derived from the metasedimentary (metapelitic) source, which could be the Mesoproterozoic basement of the Qilian Block, and the mantle-derived materials injected into their source region. The Shichuan monzonite could have a mantle-derived origin. Integrated with data from previous studies, the early-middle Silurian (437–428 Ma) intrusive rocks in the eastern part of the Qilian Block were formed during the transition period from a syn-collisional to postcollisional setting, relating to the collisional process after the consumption of North Qilian Ocean (Proto-Tethys Ocean) in the northern margin of the Gondwana continent.

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Yanshanian deformation in Western Shandong, eastern North China Craton: Response to a transition from paleo-Pacific to Pacific Plate subduction

The eastern part of the North China Craton has experienced cratonic destruction during the Mesozoic–Cenozoic period. However, the mechanism and geodynamic process of cratonic destruction is still not clear. The Shandong Province is a typical region that suffered the Yanshanian (Jurassic to Cretaceous) tectono-thermal event relating to the cratonic destruction. In this paper, we focus on the Yanshanian deformation in Western Shandong and integrate the previous studies of contemporaneous magmatism. There are two-stage compressive structures developed in Western Shandong, NE- or NNE- trending open folds, which subsequently evolved the same trend as the thrust faults. A series of NW-trending normal faults converted from the pre-existing Indosinian (Triassic) thrusts controlled the formation of Mesozoic basins. These deformations are a tectonic response to the subduction of the Izanagi Plate (paleo-Pacific Plate) under the North China Craton during the Middle Jurassic and the Early Cretaceous. The Cretaceous magmatic rocks in Western Shandong mainly occurred between 130–125 Ma and have multi-magmatic sources, including enriched lithospheric mantle, delaminated lithosphere, and subducted oceanic slab. We propose that the subduction of the Izanagi Plate converting to the Pacific Plate occurred during the middle Early Cretaceous induced a delamination of the lower crust linked to the destruction of the eastern North China Craton.

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Mkango Releases Financial Statements And Management’s Discussion And Analysis For The Period Ending September 30, 2017

Calgary, Alberta: November 28, 2017 – Mkango Resources Ltd. (AIM / TSXV: MKA) (the \’Company\’ or \’Mkango\’), is pleased to announce that it has released the Financial Statements and Management’s Discussion and Analysis for the period ending September 30, 2017. The reports will be available under the Company’s profile on SEDAR (www.sedar.com) and on the Company’s website (

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