Matrix-bound phosphine in sediments from Lake Illawarra, New South Wales, Australia

Matrix-bound phosphine (MBP) has been measured in sediment from two cores in Lake Illawarra on the south east coast of Australia. The sediments were also dated in the upper layers. MBP concentrations found range from 142 to 1813 ng kg⁻¹, dw (dry weight of sediment) with some values being amongst the highest ever measured. Values of MBP in deeper sediments were higher than for near surface samples, but the patterns with depth were not consistent. Strong correlations were noted between MBP and organic phosphorus (OP, r > 0.8) and with total phosphorus (TP, r > 0.7), but only moderate correlations were found with organic carbon (OC, r > 0.5). No correlations were found between MBP concentrations and the age of the sediments. It was confirmed that high MBP concentrations are indicative of a phosphorus rich environment. The results tend to support the premise that MBP is generated by microbial attack on OP under anaerobic conditions.     

会理—东川地区中元古代地层—构造格架

会理—东川地区是上扬子陆块出露中元古界地层最广泛的地区.以菜子园—麻塘东西向断裂带为界,之北为会理群,之南为汤丹群、东川群,断裂带内为通安组五段.均为一套浅变质的沉积岩夹火山岩.笔者等通过沉积学、火山岩岩石学和同位素地质年代学综合研究,认为中元古代( 1800～1650Ma)堆积了一套偏碱性细碧角斑岩和火山—沉积碎屑岩...     

海上低渗透油田特点及开发策略探讨

目前海油低渗探明储量和低渗的产量分别占海油总探明储量和总产量比例虽然小,但在海油实现5 000万t年产后稳产阶段所起的作用将会越来越大。对于海上10～50 mD之间的一般低渗为主要考虑的勘探开发对象,当渗透率是5～10 mD之间的特低渗油田时需要优选出构造相对简单、储层比较连续的区块开发;对于复杂断块特低渗透油田和小于5 mD的超低渗油田,在目前海上经济技术条件下暂不具备勘探开发条件。在海上低渗透油田开发中需考虑压裂、注水的综合应用,尽量采用水平井和分支井开发,并且在开采过程中注意低渗储层的保护。     

中国分县生态承载力供需平衡空间格局分析(英文)

A balanced ecological carrying capacity and its understanding are important to achieve sustainable development for human kind.Here,the concept of ecological carrying capacity has been used for measuring the dependencies between human and nature.China’s ecological balance between supply and demand has become a global concern and is widely debated.In this study the ’Ecological Footprint’ method was used to analyze the supply-demand balance of China’s ecological carrying capacity.Firstly,the ecological supply and demand balance was calculated and evaluated,and secondly,the ecological carrying capacity index (ECCI) was derived for each county of China in 2007,and finally this paper systematically evaluated the ecological carrying capacity supply-demand balance of China.The results showed that ecological deficit appeared to be the main characteristic of ecological carrying capacity supply-demand balance in 2007 of China at county scale.In general,more than four-fifths of the Chinese population was concentrated in less than one-third of the land area and more than two-thirds of the land area was inhabited by less than one-fifth of the population.The spatial distribution of the ecological carrying capacity demand-supply was unbalanced ranging from significant overloading to affluence from southeastern to northwestern part of China.It appeared to be more dominant in regions located at coastal areas which are attracted by migrants and had a generally higher population density.Along with the rapid development and urbanization trends in China,ecological deficits in these regions will become more severe.     

乌兰布和沙漠植物群落相异性及其影响因素北大核心CSCD

多样性反映群落间物种组成的相异性,是生态学研究的热点问题。通过对乌兰布和沙漠46个样地植物群落的调查数据进行分析,运用S?rensen相异性指数衡量该地区植物群落β多样性格局,并通过主成分分析、Mantel及Partial Mantel检验等方法来衡量各环境因子差异(包括气候和土壤)和群落地理距离对该区域植物群落β多样性格局的影响。结果表明:乌兰布和沙漠植物群落之间物种组成差异较大,物种周转(βsim)主导植物群落β多样性。气候因素、土壤因素和地理距离对植物群落β多样性及其周转组分有显著影响,物种周转对其响应与植物群落β多样性保持一致。乌兰布和沙漠植物群落物种在空间上的周转是环境限制和扩散限制综合作用的结果,环境过滤对植物群落β多样性及组分的影响超过扩散限制。     

Assessing the Ecological Carrying Capacity of Countries along the Belt and Road

The Belt and Road Initiative (B&R Initiative) is a crucial strategy to promote regional sustainable development in the new era. However, the realization of the B&R Initiative faces huge challenges because of the dual characteristics of a fragile eco-environment and strong dependence on ecological resources for economic development in the Belt and Road (B&R) countries. The ecological carrying capacity (ECC) is a crucial indicator for evaluating regional sustainable development. From the perspective of the relationship between the supply and consumption of ecological resources, this study uses net primary productivity data to measure the supply capacity of ecological resources, and it uses the agricultural production and trade data provided by the United Nations Food and Agriculture Organization to measure the level of ecological resource consumption. These supply and consumption data are then used to assess the ECC and ecological carrying status (ECS) of the B&R countries in 2017. The results show that: (1) The ECC of the B&R is 11.097 billion people; the ecosystem can also support 6.433 billion people, and the ECC is in a state of rich and surplus. (2) The ECS is polarized among the regions and countries along the B&R. Of the 65 countries, the ECC of 40 countries is in a rich and surplus state, mainly in Mid-East Europe and Southeast Asia, while the ECC of 19 countries is in severe overload, mainly in West Asia/Middle East. (3) Although the ecosystems still have ample carrying space in countries along the B&R, ecological protection is still facing enormous challenges during the implementation of the B&R Initiative combined with the internationally recognized ecological protection standards as well as the forecasts of the population and economic development. As the core content of building a new international trade network, the B&R Initiative will help to solve the spatial mismatch between the supply and consumption of ecological resources, which provides a new opportunity to coordinate the contradiction between the ecological protection and social demands of the B&R countries.     

Extent of underthrusting of the Indian plate beneath Tibet controlled the distribution of Miocene porphyry Cu–Mo ± Au deposits

Miocene igneous rocks in the 1,600 km-long E–W Gangdese belt of southern Tibet form two groups separated at longitude ～89° E. The eastern group is characterized by mainly intermediate–felsic calc-alkaline plutons with relatively high Sr/Y ratios (23 to 342), low (⁸⁷Sr/⁸⁶Sr)_i ratios (0.705 to 0.708), and high εNd_i values (+5.5 to ?6.1). In contrast, the western group is characterized by mainly potassic to ultrapotassic volcanic rocks with relatively high Th and K₂O contents, low Sr/Y ratios (11 to 163), high (⁸⁷Sr/⁸⁶Sr)_i ratios (0.707 to 0.740), and low εNd_i values (?4.1 to ?17.5). The eastern plutonic group is associated with several large porphyry Cu–Mo ± Au deposits, whereas the western group is largely barren. We propose that the sharp longitudinal distinction between magmatism and metallogenic potential in the Miocene Gangdese belt reflects the breakoff of the Greater India slab and the extent of underthrusting by the Indian continental lithosphere at that time. Magmas to the east of ～89° E were derived by partial melting of subduction-modified Tibetan lithosphere (mostly lower crust) triggered by heating of hot asthenospheric melt following slab breakoff. These magmas remobilized metals and volatile residual in the crustal roots from prior arc magmatism and generated porphyry Cu–Mo ± Au deposits upon emplacement in the upper crust. In contrast, magmas to the west of ～89° E were formed by smaller volume partial melting of Tibetan lithospheric mantle metasomatized by fluids and melts released from the underthrust Indian plate. They are less hydrous and oxidized and did not have the capacity to transport significant amounts of metals into the upper crust.     

A bond-based smoothed particle hydrodynamics considering frictional contact effect for simulating rock fracture

Acta Geotechnica - A bond-based smoothed particle hydrodynamics considering hybrid friction contact (BB-SPH-HFC) method is proposed to simulate the dynamic friction behavior during crack initiation...     

The First Quantitative Slip-Rate Estimated Along the Ashikule Fault at the Western Segment of the Altyn Tagh Fault System

<正>As one of the longest strike-slip fault in Asia,the Altyn Tagh Fault(ATF)defines the northern boundary of the Tibetan Plateau and plays a significant role inaccommodating the deformation resulting from the IndiaAsia convergence.Slip-rate and seismic behavior of the fault are critical to understand the present-day kinematics