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Igneous rocks have the characteristics of “diversification of eruption mode, diversification of lithologic origin and multiple changes of mineral assemblages ", so it is difficult to identify fine. This study is based on a real case study of igneous carboniferous reservoir in Jinlong 10 block at Junggar basin. The distinguish of the reservoir-developed rocks are catalyzed to basalt, andesite, dacite, granite, tuff and volcanic breccia rock, based on a combination of core and thin sheet analysis data. Based on the characteristics of log response of different lithology, the basic basalt, neutral andesite and acidic granite are quickly distinguished by N-DP intersection map method, and the idea of “step by step stripping” is adopted in the interval, and tuff and volcanic breccia are identified by intersection map method. The results of lithology identification and the conclusion of core sheet analysis have a high degree of anastomosis, which effectively improves the accuracy of lithology identification.

Shale gas is an important unconventional natural gas resource. Different from conventional oil and gas exploration, gas shale is not only the source rock of natural gas, but also the cap rock and reservoir. This paper presents a logging interpretation method for comprehensive evaluation of shale gas. Taking well A in southeast Chongqing from Sichuan Basin as an example, the shale gas reservoir of Wufeng-Longmaxi formation is evaluated. This method makes full use of conventional logging data (gamma ray, array lateral resistivity, density, neutron, acoustic, spectral gamma ray), unconventional log data (NMR Nuclear Magnetic Resonance, ECS Elemental Capture Spectroscopy) and core experiment data (X-ray Diffraction, Tight Rock Analysis, Methane Adsorption Isotherm). This method of combining logging data with core measurement can provide mineralogy, porosity, permeability, saturation, kerogen volume, total organic carbon content, absorbed gas content and free gas content. The methods provide a means to understand the petrophysical properties and reservoir quality of Wufeng-Longmaxi shale. This information can help to determine the “sweet spot” along the vertical to land and design a selective completion strategy to optimize well productivity.

The formation evaluation in a primary formation of a CO2 sequestration project in Western Australia has been very challenging due to the presence of glauconite and other iron rich minerals. The conventional method cannot handle the mineralogy effects, hence the accurate porosity, clay type and clay content cannot be calculated accurately. The latest generation in spectroscopy technology LithoScanner was brought to the project and run in well A for the first time in Australia. The tool has a high output pulse neutron generator and unique cerium-doped lanthanum bromide (LaBr3:Cr) gamma ray detector. This combination enables the tool to measure both inelastic and capture spectra for an expanded set of elements from that of previous-generation tools. We are measuring elements that make up more than 99% of the average abundance in the earth’s crust. Measuring the elements is the starting point to calculate minerals, matrix density and those are key to obtain accurate reserves estimates (porosity) and build an accurate petrophysical and reservoir model. For well A, the LithoScanner elements weight fractions are used in the Techlog QuantiElan module to solve mineralogy that includes quartz, K-feldspar, calcite, siderite, pyrite, illite, kaolinite, glauconite and chlorite. There is a very good agreement between the computed mineralogy and the mineralogy from core measurements. LithoScanner provides a continuous log of matrix density that is used as an input to porosity calculations. This formation evaluation based on Litho Scanner does not require the subjective inputs from the log analysis, but completely rely on the tool’s reading. It can be used for both simple and complex formation to obtain the good consistency and accurate answers.

Conventional digital core reconstruction methods are not suitable for deep shale gas reservoirs with low porosity and permeability, anisotropy and complex mineral composition, and conventional single resolution three-dimensional digital core structure model cannot fully describe the core structure of shale gas reservoirs of different scales. In this paper, the advantages and disadvantages of different digital core reconstruction methods are summarized by analyzing examples. It is found that MCMC core reconstruction method is more suitable for image reconstruction of 3D digital structure model core of deep shale gas reservoir in China; Finally, in view of the problems existing in conventional digital core reconstruction methods, combining CT imaging with ion beam focused electron microscopy (FIB-SEM) imaging technology, a 3D digital core structure model with multi-scale, multi-component and corresponding macro pore and micro pore of the corresponding reservoir is proposed. The micro spatial distribution structure of the model is similar to that of real shale gas reservoir core, it overcomes the difficulty that the resolution of single scale 3D digital gas reservoir core model and the micro size characteristics of gas reservoir core cannot be perfectly considered. It can not only accurately describe the micro pore space distribution structure of real core gas reservoir, but also accurately describe the macro heterogeneity of deep shale gas reservoir core.

In this paper, the shale oil shale stratum in Jiyang Depression is taken as the object to study the characteristics of the complex shale lithology, the frequent development of calcareous or sandy stratum, and the difficulty of manual identification. Firstly, the development characteristics of the stratigraphic layer of continental shale oil reservoir are studied. Then the electric imaging logging image is processed to restore the whole borehole wall, and then the target geological object is extracted through the operations of automatic image segmentation, connected area labeling, area contour tracking extraction and storage. Finally, the target geological objects are automatically classified and identified, the location of the continental shale texture layer is predicted, and the texture layer development index is calculated. The research results show that: after verification analysis with the core description, this method can identify the texture layer more accurately, and the coincidence rate reaches 92%. It provides support for the identification of stratigraphic facies favorable for reservoir development in the study area, and also lays a foundation for shale oil layer selection and fracturing.

The complex structural conditions of marine shale in Western Chongqing area lead to the problems of insufficient understanding of pore structure, unclear direction of in-situ stress and poor fracturing effect, which lead to the difficulty of shale gas development. Based on the experimental study and logging data, the calculation model of in-situ stress is established. Finally, the influencing factors of in-situ stress are analyzed. The results show that the distribution of three-direction stress in the target interval is σH>σv>σh, and the experimental and logging results are consistent. As a whole, the in-situ stress tends to decrease with the increase of depth, with little fluctuation and good continuity. The fragility characteristics of the reservoir are relatively good, and it is easier to form various cracks that are widely developed.

The cam and tappet are key components of the internal combustion engine valve train system. Due to the alternating high-frequency cyclic of high contact stress, the cam and tappet are prone to abnormal wear and failure. In this work, Cr12W steel was selected as the material of the roller tappet in valve train. Then, it was treated by ion nitriding treatment. The fretting wear tests were carried out under laboratory conditions. The wear mechanisms of nitrided and untreated specimens which rubbed with GCr15 steel were investigated under dry friction and oil lubrication, respectively. It is found out that the predominant wear mechanisms of nitrided specimens under dry friction are slight abrasive wear and adhesive wear, whereas under oil lubrication, it is mainly spalling. The wear mechanisms of untreated specimens under dry friction are identified as adhesive wear and oxidative wear, while it is mainly abrasive wear under oil lubrication.

The evaluation of irreducible water saturation is important for qualitative and quantitative prediction of residual oil distribution. However, it is to be improved for the accuracy of experimental measuring the irreducible water saturation and logging evaluation. In this paper, firstly the multi-functional core flooding experiment and the nuclear magnetic resonance centrifugation experiment are carried out in the west of Sulige gas field. Then, the influence was discussed about particle size, porosity and permeability on the water saturation. Finally, the evaluation model was established about irreducible water saturation and the evaluation of irreducible water saturation was carried out. The results show that the results of two experiments are both reliable. It is inversely proportional to the median particle size, porosity and permeability, and is most affected by the median particle size. The water saturation of the dry layer is higher than that of the general reservoir. The worse the reservoir property, the greater the water saturation. The test results show that the irreducible water saturation model can be used to evaluate the water floor.