The salt chimney effect: delay of thermal evolution of deep hydrocarbon source rocks due to high thermal conductivity of evaporites

Half of the topseals to the world's largest oilfields are evaporites. Rock salt has a thermal conductivity two to four times greater than that of other sedimentary rocks found in oil‐ and gas‐bearing basins. Strong heat conduction through evaporites can increase the geothermal gradient above evaporite deposits, resulting in a positive thermal anomaly and above‐average temperature while simultaneously decreasing the geothermal gradient below evaporites, resulting in a negative thermal anomaly. Most Triassic–Jurassic hydrocarbon source rocks in the Kuqa Basin, western China, are overlain by ~1500‐m‐thick Tertiary evaporites with underlying Cretaceous sandstones and mudstones. Directly measured strata temperatures indicate an obvious break in the steepness of the geothermal gradient above and below Paleogene evaporites, with a significantly steeper geothermal gradient above the evaporites. Simulations of the thermal evolution of source rocks based on data collected from well Kela‐2 indicate that if the thickness of evaporites (mainly rock salt and anhydrite rock) in overlying rocks above source rocks increases compared with the thickness of siliciclastic rocks in the overlying rocks, then strata temperatures and vitrinite reflectance in Jurassic source rocks will decrease accordingly. Our thermal simulations based on the thickness and thermal conductivity of evaporites accurately coincide with previous studies based on homogenization temperatures, hydrocarbon–water contact retrospection, and carbon isotope results from natural gases. The gas generation center located in the Kalasu Tectonic Belt today is also sealed in an evaporite‐related structural trap that formed at this time. Therefore, the speculated natural gas generation times not only correlate with the evaporite‐related structural trap formation, but the calculated maturity of deep source rocks below the evaporites also coincides with current gas reserves. And our studies can help to find the deep oils and gases under thick evaporites.     

The People’s Liberation Army Rocket Force: reshaping China’s approach to strategic deterrence

The Chinese People’s Liberation Army (PLA) is in the midst of a sweeping reform programme to significantly transform its organisation, force posture, command and control structures, and internal politics. Among the many important aspects of this effort is the establishment of the PLA Rocket Force (PLARF). Creation of the PLARF solidified China’s missile forces as a critical element of China’s evolving strategic deterrent posture, portends continued significant investment in PLARF modernisation, and points to a more concerted effort to integrate PLARF capabilities into more effective PLA-wide joint operations—all key developments in the fundamental reshaping of China’s approach to strategic deterrence. These developments will affect U.S. strategic and extended deterrence postures, U.S.-China strategic stability, allied conventional force operations, information dominance and security, critical infrastructure, and other key aspects of national security. This study details the organisational, technological, and doctrinal changes afoot for the PLARF, and analyses how—if successful—they affect U.S. and U.S-allied military strategy in the Indo-Pacific region.     

Ontogenetic scaling and lithic systematics: method and application

Stone tools tend to be classified according to a mix of functional, morphological, and technological attributes. This practice results in confusions when large-scale assemblage comparisons are made with the aim of investigating phylogenetic relationships, as functional and cultural information is aggregated. It is argued here that functional criteria must be assessed separately, and that resharpening, as a uniform, repeated, conscious behavioral process of tool maintenance that indexes use and function, can provide a solution to this problem. The subject of this article is a quantitative method for extracting and comparing resharpening trajectories. The method is an adaptation of ontogenetic scaling methods from biology, and is based on obtaining a mathematical representation of shape and size, and finding a relationship between the two. Elliptical Fourier analysis is applied to stone tool contours in order to extract shape information, and then a series of regressions of shape on size provide trajectory vectors. The angles between these are then calculated and subjected to a variety of multivariate statistical tests. A case study involving several European Middle Paleolithic bifacial and unifacial tool assemblages is presented. The results show that resharpening and maintenance can be independent of morphology and technology, suggesting that there are strong grounds for focusing on functional systematics separately.     

北周墓葬的地下空间与设施

本文通过对北周墓葬形制、随葬品布局、壁画内容和布局等资料的整理和总结,明确了北周墓葬地下空间与设施的特点。论文重点讨论了北周墓葬形制中最具特色的前后双室墓出现的背景和原因,壁龛设置的非制度性,壁画的象征意境,以及田弘墓的特殊性等问题。     

对女性生命价值的探寻--读白玉芳女士的《秋霄落雁女儿情》

白玉芳女干所的《秋霄落雁女儿情》,从少数民族女作家的视角描写了战争中的女性,本着重评论了女作家描写战争中女性所表现的特点,主要有三方面,一,女性生命生存状态的复现;承担与回避;二,历史场景中女性的理性与情感交错;三,神话事故与女性情绪的有机结合。     

青海省公务员培训需求调查

客观、准确地了解公务员的培训需求,对行政学院有效开展公务员培训有着非常重要的意义。本文在深入调查的基础上,分析了青海省县(处)级公务员的培训需求及特点,并就今后的公务员培训工作提出了初步的意见和建议。     

清代大理白族纠纷的解决规范

在清代的大理白族地区,中央王朝汲取了大量白族固有规范营养,不断推广其统一规范,而另一方面,大理地区白族纠纷解决规范也朝着中央王朝靠拢.