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The Tarim area in this paper refers to the present Tarim Basin and its surrounding mountains, bounded on the north by the Middle Tianshan Mountains, on the south by the Kunlun Mountains, on the west by the national boundary of China, and on the east by the Altun Mountains. It covers an area of more than 1 000 000 km 2 . Based on the quantitative and qualitative data from the stratigraphy and petrology of outcrop and well sections, and according to the single factor analysis and multifactor comprehensive mapping method, the single factor maps of the Lower, Middle and Upper Cambrian, and the lithofacies palaeogeography maps of the Early, Middle and Late Cambrian of the Tarim area, are compiled. The most important character of these lithofacies palaeogeography maps is quantification, i.e. the determination of each palaeogeography unit based on accurate quantitative data and the quantitative single factor maps. The study marks the first time that this quantitative method has been applied in the Tarim area. In the Early Cambrian, the present Tarim Basin was mainly a carbonate platform, in which there were penebank, dolostone flats, and gypsum-halite lake. The South Tianshan Basin and East Tarim Basin were siliceous rocklimestone-mudstone basins. The Kunlun Platform was situated in the south, where there were two small lands. The Altun Land was situated in the southeast. In the Middle and Late Cambrian, the framework of lithofacies palaeogeography was similar to that in the Early Cambrian; the land area was gradually reduced; the basin area was enlarged; while the Tarim Carbonate Platform changed little. The transgression continued from the Early Cambrian to the Late Cambrian.

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An integration of small-angle neutron scattering (SANS), low-pressure N 2 physisorption (LPNP), and mercury injection capillary pressure (MICP) methods was employed to study the pore structure of four oil shale samples from leading Niobrara, Wolfcamp, Bakken, and Utica Formations in USA. Porosity values obtained from SANS are higher than those from two fluid-invasion methods, due to the ability of neutrons to probe pore spaces inaccessible to N 2 and mercury. However, SANS and LPNP methods exhibit a similar pore-size distribution, and both methods (in measuring total pore volume) show different results of porosity and pore-size distribution obtained from the MICP method (quantifying pore throats). Multi-scale (five pore-diameter intervals) inaccessible porosity to N 2 was determined using SANS and LPNP data. Overall, a large value of inaccessible porosity occurs at pore diameters <10 nm, which we attribute to low connectivity of organic matter-hosted and clay-associated pores in these shales. While each method probes a unique aspect of complex pore structure of shale, the discrepancy between pore structure results from different methods is explained with respect to their difference in measurable ranges of pore diameter, pore space, pore type, sample size and associated pore connectivity, as well as theoretical base and interpretation.

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