The Tanshan area is located in the southern section of the west margin of the Ordos basin. The Middle Jurassic Yan’an Formation is relatively thick and rich in coal and oil shale layers, having positive potential for energy development. In order to explore the sedimentary environment of oil shale and the controlling factors of organic matter accumulation, 18 oil shale samples collected from two boreholes (Guyou-3 and Guyou-4) in the Tanshan area were selected as the research objects, and organic geochemical and elemental geochemical tests were carried out systematically. The results show that oil shales have the characteristics of medium oil content, medium ash, high calorific value, low sulfur and low maturity stage, which constitutes good hydrocarbon generation potential. The organic matter is mainly humic type, resulting from terrigenous debris and higher plant debris. The indictors of C-value (mean 81.90), Th/U ratio (mean 3.44), CaO/(MgO·Al2 O3) ratio (mean 0.07), δEu (mean 0.71), δCe (mean 1.15), V/(V + Ni) ratio (mean 0.79), Ceanom index (mean −0.04), Babio index (mean 488.97 μg/g), P/Ti ratio (mean 0.08), TOC/S ratio (mean 59.80), Sr/Ba ratio (mean 0.57) and (La/Yb)N ratio (mean 14.71) indicate that Tanshan oil shales were formed in a warm–humid climate and anoxic-reducing environment, with a low-salinity water body and a low deposition rate but also a relatively low initial paleoproductivity. Paleoclimate conditions, organic matter sources and redox properties of paleowater are the main controlling factors affecting the accumulation of organic matter in oil shales. Although low paleoproductivity and deposition rates are not conducive to the preservation of organic matter, under the conditions of warm and humid climate and a reducing water environment, the continuous and stable input of terrigenous debris and higher plant debris can also cause the enrichment of organic matter.

High Ba-Sr granitic rocks are widespread in Phanerozoic orogenic systems, and their petrogenesis is important for revealing the evolutionary process of the Proto-Tethys Ocean in the North Qilian orogenic belt. This paper presents a combination of zircon U-Pb age, whole-rock major and trace element concentrations, and Sr-Nd-Hf isotopic data for Caowa high Ba-Sr dioritic intrusion from the eastern part of the North Qilian orogenic belt, aiming to decipher its petrogenesis and tectonic setting. LA-ICP-MS zircon U-Pb dating yield an emplacement age of 450 ± 2 Ma for the Caowa intrusion, indicating a magmatic activity of the Late Ordovician. The Caowa quartz diorites contain moderate contents of SiO2, MgO, Mg#, and resultant high concentrations of Na2O + K2O, Fe2O3T, and Al2O3, displaying calc-alkaline and metaluminous characteristics. The studied samples have relatively elevated Ba (up to 1165 ppm) and Sr (561 to 646 ppm) contents, with obvious enrichment in LILEs (e.g., Ba, Th, U) and depletions in HFSEs (e.g., Nb, Ta, Ti), resembling those of typical high Ba-Sr granitoids in subduction zones. Together with enriched Sr-Nd isotopic composition [(87Sr/86Sr)i = 0.7082–0.7086, εNd(t) = −5.1 to −4.9], and the wide ranges of zircon εHf(t) values (−13.2 to +8.5), it suggests that these high Ba-Sr quartz diorites were derived from a mixture magma source between the ancient crust materials and the enriched lithospheric mantle metasomatized by fluid released from subducted oceanic crust or sediment. Taking into account the ophiolites, high pressure metamorphic rocks, and arc magmatic rocks in the region, we infer that due to the influence of the northward subduction of the Qilian Proto-Tethys Ocean, the Laohushan oceanic crust of the North Qilian back-arc basin was subducted during the Late Ordovician and resulted in extensive metasomatism of lithospheric mantle by fluids derived from oceanic crust or sediments, and the Caowa high Ba-Sr quartz diorites were generated in the process of crust–mantle interaction during the Late Ordovician.

The petrogenesis of high Ba-Sr granitoids provide a great significance to penetrate the Proto-Tethys evolution in the North Qilian orogenic belt. This paper presents a combination of zircon U-Pb age, whole-rock major and trace element concentrations, and Sr-Nd-Hf isotopic data for Caowa high Ba-Sr dioritic intrusion from the eastern part of the North Qilian orogenic belt, aiming to decipher its petrogenesis and tectonic setting. LA-ICP-MS zircon U-Pb dating yields an emplacement age of 447±3 Ma for the Caowa intrusion, indicating a magmatic activity of the late Ordovician. The Caowa quartz diorites contain moderate contents of SiO2, MgO, Mg# and resultant high concentrations of Na2O+K2O, Fe2O3T and Al2O3, displaying calc-alkaline and metaluminous characteristics. Their relatively elevated Ba (up to 1165 ppm) and Sr (561 to 646 ppm) contents, with obvious enrichment in LILEs (e.g. Ba、Th、U) and depletion in HFSEs (e.g. Nb、Ta、Ti) resemble those of typical high Ba-Sr granitoids in subduction zone. Together with enriched Sr-Nd isotopic compositons[(87Sr/86Sr)i=0.7082−0.7086, εNd(t)= -5.1 to -4.9], and relatively extensive εHf(t) values (-13.2 to +8.5) of zircons, it suggests that these high Ba-Sr quartz diorites were derived from a mixture magma source between the ancient crust materials and the enriched lithospheric mantle metasomatised by fluid was released from subducted oceanic crust or sediment. Taking into account the ophiolites, high pressure metamorphic rocks and arc magmatic rocks in the region, we infer that affected by the northward subduction of the Qilian Proto-Tethys ocean, the Laohushan oceanic crust of the North Qilian back-arc basin was subducted during the Late Ordovician and resulted in extensive metasomatism of lithospheric mantle by fluids derived from oceanic crust or sediments, and the Caowa high Ba-Sr quartz diorites generated in the process of crust-mantle interaction during the Late Ordovician.

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The museum is an important institution for carrying out ecological civilization education and improving the quality of the ecological civilization of people. At present, how to effectively improve the immersion and knowledge of the exhibition is an important topic facing the Chinese museum ecological civilization exhibition. The combination of the concept of actual environment experience and digital technology provides a new way to enhance the educational effect of the museum's ecological civilization. Taking the practice of the Hoh Xil Ecological Exhibition Area of Beijing Forestry University Museum as an example, this paper introduces the exhibition area with the guidance of the real experience principle, and builds a highly realistic ecological scene, combined with biological specimens from the original ecological environment and interactive digital media. The good ecological civilization missionary effect has provided new ideas for the ecological civilization education of Chinese museums.