区域变质作用与中国大陆地壳的形成与演化

在编制1∶500万中国变质地质图的基础上,本文总结了中国主要变质带的演化以及各变质带与中国大陆地壳形成演化之间的内在联系。虽然在华北和华南克拉通都有古太古代到中太古代的变质年代记录,但是由于后期改造其变质作用的特点及与区域构造背景的联系已难以追索。新太古代末-古元古代初期的变质作用在华北克拉通表现最明显,这期变质作用紧随大规模的TTG岩浆作用,普遍具有逆时针的P-T演化轨迹,反映了地幔柱主导的岩浆-变质事件特点。古元古代晚期的变质事件在华北、华南、塔里木克拉通都有强烈反映。这期变质作用以形成具有顺时针P-T演化轨迹的高压麻粒岩为特点,与形成Columbia超大陆的一些造山带的特点类似,但是这三个不同克拉通在与Columbia聚合的时间和空间方位上存在差异。华南克拉通是相对年轻的克拉通,是沿新元古代江南造山带扬子和华夏地块拼合的产物。新元古代江南造山带的火山岩形成时代和变质作用程度从北东向南西迁移,反映了造山过程逐渐迁移和剪刀式闭合的特点。形成华南克拉通后,在其东南缘又先后经历了加里东期和印支期的变质改造,并且由北西向南东变质带从加里东期转变为印支期,但是这两期变质作用的构造背景尚不很清楚。中国南北大陆的聚合首先从西昆仑-阿尔金-北祁连-北秦岭-桐柏开始,所反映的变质作用是早古生代的蓝片岩相和榴辉岩相变质岩相伴产出,表明经历了从洋壳俯冲到陆陆碰撞的演化过程。中国东部的南北大陆到印支期才最终汇聚,相应的变质作用以南部出现高压蓝片岩相、北部出现超高压的榴辉岩相变质带为特点,表明南方大陆向北方大陆的俯冲。超高压带内普遍含有柯石英,意味着大规模的陆壳深俯冲。华北克拉通和塔里木克拉通以北的中亚造山带内存在多条从早古生代到晚古生代的变质带和多条蓝片岩相变质带,表明这是一个由多阶段、多条变质带组成的造山区。但是其变质作用的空间和时间演化还有待进一步深入。青藏高原变质带具有北老南新的空间分布特点,最北部的印支期龙木错-双湖-澜沧江变质带反映了原特提斯和古特提斯洋的碰撞拼合过程,北部的燕山期班公湖-怒江变质带和中部的喜马拉雅早期雅鲁藏布江变质带反映了新特提斯洋的两次碰撞拼合过程,南部喜马拉雅晚期的高喜马拉雅变质带反映了印度板块向北俯冲导致的高原快速隆升过程。     

Monitoring the recovery of a previously exploited surf-zone fish community in the St Lucia Marine Reserve,South Africa,using a no-take sanctuary area as a benchmark

Limiting accessibility to a fishing area can reduce fishing effort effectively and may therefore promote local recovery of depleted stocks. In January 2002, beach driving was banned in South Africa, thereby reducing angler access to large areas of the coastline, particularly in less-developed areas. In November 2001 a project had been established in the St Lucia Marine Reserve, on the east coast of South Africa, to compare surf-zone fish populations inside a no-take sanctuary zone with those in an adjacent exploited area. Subsequent to the ban, the aim of the project was adapted such that surf-zone fish populations were monitored for potential recovery in what had been the exploited area, located to the north of Cape Vidal, which anglers could no longer access easily, because of the prohibition on beach driving. Standardised research fishing was conducted at two sites in the previously exploited area and two sites in the no-take sanctuary. Conventional stock-status indicators showed evidence of recovery in the four most common species caught in the previously exploited area, in terms of both abundance and biomass. Generalised additive mixed models were used to account for the influence of targeting specific species; however, subtle differences in habitat between the sampling sites, improved angling skill over time, variability in recruitment, and differential species-specific responses complicated interpretation of results. The implications of the findings are discussed in terms of the future monitoring and management of marine protected areas both within the St Lucia Marine Reserve and farther afield.     

深海半潜浮式生产平台关键理论与技术问题

深海半潜浮式生产平台FPU(floating production unit)是国际海洋油气资源开发的关键基础性装备。针对半潜浮式生产平台的技术特点,系统阐述其各方面特性(包括:总布置、系泊和立管、水动力性能、结构设计与分析等)及相关研究现状和未来发展趋势。并结合我国南海地理、水文和资源环境等特点,对未来半潜浮式生产平台的开发提出了一些建议。     

Characterizing the urban temperature trend using seasonal unit root analysis: Hong Kong from 1970 to 2015

This paper explores urban temperature in Hong Kong using long-term time series. In particular, the characterization of the urban temperature trend was investigated using the seasonal unit root analysis of monthly mean air temperature data over the period January 1970 to December 2013. The seasonal unit root test makes it possible to determine the stochastic trend of monthly temperatures using an autoregressive model. The test results showed that mean air temperature has increased by0.169?C(10 yr)~(-1)over the past four decades. The model of monthly temperature obtained from the seasonal unit root analysis was able to explain 95.9% of the variance in the measured monthly data — much higher than the variance explained by the ordinary least-squares model using annual mean air temperature data and other studies alike. The model accurately predicted monthly mean air temperatures between January 2014 and December 2015 with a root-mean-square percentage error of 4.2%.The correlation between the predicted and the measured monthly mean air temperatures was 0.989. By analyzing the monthly air temperatures recorded at an urban site and a rural site, it was found that the urban heat island effect led to the urban site being on average 0.865?C warmer than the rural site over the past two decades. Besides, the results of correlation analysis showed that the increase in annual mean air temperature was significantly associated with the increase in population, gross domestic product, urban land use, and energy use, with the R~2 values ranging from 0.37 to 0.43.     

Renaming and Rebranding within U.S. and Canadian Geography Departments, 1990–2014

Between 2000 and 2014, more than thirty geography departments adopted revised or new names, with some entirely dropping geography. Although renaming and rebranding efforts are not new to higher education, the rapid pace at which geography department names have changed raises questions about the discipline's identity and health. We examine the renaming trend within geography programs together with intended and unexpected factors as perceived by faculty. Specifically, we look at the renaming and rebranding trend within the context of four pillars offered by Pattison (1964 Pattison, W. D. 1964. The four traditions of geography. Journal of Geography 63 (5): 211–16.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) to define geography's principal academic domains—earth-science, man–land, area/regional studies, and spatial traditions.     

褐藻胶结构的统计学描述及其应用

从褐藻胶线性链块结构的本质出发,运用结构单元的特征性及简单的统计原理,得到了各种结构单元频率之间的相互关系,并阐述了这些结构参数的化学意义,及其初步的应用,从而发现了一些实验现象的理论依据。为探讨褐藻胶组成、结构、功能之间的关系,建立一个对组成、结构定量描述的参数系数。