Determination of the regional deformation rates of Shanghai and Kashima VLBI stations based on ITRF97

The vertical deformation rates (VDRs) and horizontal deformation rates (HDRs) of Shanghai VLBI station in China and Kashima and Kashima34 VLBI stations in Japan were re-analysed using the baseline length change rates from Shanghai to 13 global VLBI stations, and from Kashima to 27 stations and from Kashima34 to 12 stations, based on the NASA VLBI global solution glb1123 (Ma, 1999). The velocity vectors of the global VLBI stations were referred to the ITRF97 reference frame, and the Eulerian vectors of different models of plate motion were used for comparative solutions. The VDR of Shanghai station is estimated to be −1.91±0.56 mm/yr, and those of Kashima and Kashima34 stations, −3.72±0.74mm/yr and −8.81±0.84mm/yr, respectively. The difference between the last two was verified by further analysis. Similar estimates were also made for the Kokee, Kauai and MK_VLBA VLBI stations in mid-Pacific.     

未来的国际天球参考架

本文简述了国际天球参考架的发展历史和现在射电参考架的现状—基准源选择的标准和参考架的稳定性。描述了地面上光学观测在依巴谷参考架的维持和加密的一系列工作。介绍由天体测量卫星GAIA和SIM给出的天球参考架可能逵到的精度。详述了在今后十年中地面天体测量的作用以及正在开展有关天球参考架的研究课题 ,同时也列出了我国正在和即将开展天体测量的几个研究课题     

菏泽市地质灾害现状与防治

菏泽市地质灾害类型主要为地震、地面塌陷、地面沉降、地裂缝、砂土液化、土地盐渍化及地氟病等，其发育与分布受地质构造、水文地质条件的控制以及气象、人类活动等因素的影响。就其分布、危害、致灾原因等做了分析，并提出了防治建议和对策。     

Isotopic studies of leaf water. Part 1: A physically based two-dimensional model for pine needles

Understanding of isotopic variations in leaf water is important for reconstruction of paleoclimate and assessment of global biochemical processes. We report here a study of isotopic distributions within a single needle of two pine species, Pinus resinosa Ait and Pinus strobes L., with the objective of understanding how isotopic compositions of leaf water are controlled by environmental and physiological variables. A 2D model was developed to simulate along-leaf isotopic variations and bulk leaf water isotopic compositions. In addition to variables common to all leaf water isotopic models, this 2D model also takes into account the specific geometry and dimensions of pine needles and the isotopic transport in xylem and mesophyll. The model can successfully simulate oxygen isotopic variations along a single needle and averaged over a leaf (bulk leaf water). The simulations suggest that isotopic composition of the bulk leaf water does not always depend only upon the average transpiration rate, which in turn raises questions about using leaf water isotopic values to estimate transpiration rates. An unsuccessful attempt to simulate along-needle hydrogen isotopic variations suggests that certain unknown biological process(es) may not have been incorporated into our 2D model, and if so, it calls for a reevaluation of all other models for hydrogen isotopic simulations of leaf water since they too lack these processes.Existing leaf water isotopic models are reviewed in this work. In particular, we evaluate the most frequently used model, the stomatal boundary layer model (also referred to as the Craig-Gordon model). We point out that discrepancy between the boundary layer model and the measured bulk leaf water seems to depend upon relative humidity. Using our 2D model, we show that this humidity dependency is a result of an interplay between environmental and physiological conditions: if the transpiration rate of plant leaves decreases with increasing relative humidity, our 2D model can reproduce the pattern of isotopic discrepancy between boundary layer model predictions and observations, enabling us to understand better the reason behind this discrepancy.     

江苏潮滩沉积物激光粒度仪与移液管-筛析分析结果的对比

激光粒度仪的广泛应用带来了与历史数据的对比问题,因此需要建立激光粒度仪与早期分析结果之间的关系。根据江苏海岸潮滩沉积物样品的激光粒度仪和移液管-筛析法分析,对粒度参数、粒度组分等进行了对比,对两种方法的差异进行了分析。结果表明,对于江苏潮滩沉积物粒度参数中平均粒径的激光粒度仪与移液管-筛析分析结果之间有良好的线性关系;筛分法测得的粗颗粒物质较激光法偏少,而移液管法法测得的细颗粒物质较激光法偏多;将样品分类之后再进行两种方法所获粒度参数的回归分析,相关性得以提高,说明不同粒度组成的沉积物对分析结果的对比有不同的影响。两种方法之间的换算关系不仅与研究区域有关,而且与沉积物本身的粒度组成有关。     

一株胶质芽胞杆菌对磷矿石风化作用的实验研究

以一株质芽孢杆菌为例研究实验条件下微生物对磷矿石的风化作用.以直接作用和间接作用的方式研究培养基中胶质芽孢杆菌对磷矿粉的风化作用,即在装有100目磷矿石粉的液体培养基中接种,研究该菌对磷矿石粉的直接风化作用;同时,将装有100目磷矿石粉的透析袋放入液体培养基中再接入该菌,研究其对磷矿石粉的间接风化作用.按不同时间取培养液上清液,过滤,用电感耦合等离子体发射光谱(ICP-OES)测定滤液中Ca2 、Mg2 、Na 、Mn2 、Al3 、Fe3 和K 等浓度,比色法测定水溶性P(Pws)和水溶性Si (Siws) 的含量;滤膜上的固体物称重并消解后,同上方法测定Ca2 、Mg2 、Na 、Mn2 、Al3 、Fe3 和K 等浓度以及Pws和Siws含量.此外,细菌风化作用后的矿物残渣用电子探针作表面微观形态分析和XRD矿物物相分析.结果表明:胶质芽孢杆菌对磷矿石粉风化的直接作用强度大于间接作用;对不同矿物的风化强度不同,对粘土矿物的风化作用较明显.提出细菌对磷矿石的风化作用源自细菌生长导致的机械破坏作用、胞外分泌物的生化降解作用以及多种因素之间的协同作用.     

油田水动力系统与油气藏的形成

油田水中存在“沉积承压水”和“地表渗入水”两个相对独立而又相互作用的水动力系统,前者由上覆地层重量所引起的地静压力以及地静压力等引起的异常孔隙流体压力所形成,具有内循环承压式水交替特征,后者为大气降水和地表水向储集层的渗入而形成,以外循环渗入或水交替为特征。这两大系统（尤其是前者）的作用在很大程度上控制了含油气盆地中油气的运移、聚集和保存,油气聚集区主要位于水文地质带中的交管阻滞一停滞带内,沉积交替强度的低值区是油气富集区,沉积水的离心流使凹陷中的油气围绕凹陷中心呈带状分布。     

珠江口河流输沙、河口沉积与粒度信息之间的联系

河口三角洲地区泥沙供应充分，是现代沉积速率较高的区域。快速沉积的泥沙包含高分辨率的环境信息。采用放射性同位素测年方法研究了珠江口伶仃洋大铲湾海域6个柱样的现代沉积速率，以2mm的间隔分析了其中2个柱样上部的粒度，并对其平均粒径和珠江流域的年输沙量进行了快速傅里叶变换，以期获取河流泥沙供应、河口沉积速率和沉积物垂向粒度变化的对应关系。结果表明，大铲湾海域的沉积速率为1～3cm／a，受动力条件和泥沙供应条件的影响显著。2个柱样的平均粒径的最显著重现周期与珠江年输沙量的周期性有较好的对应关系，并可能反映了季节的、年的和多年的沉积速率信息。对于每年沉积厚度在厘米级的环境，以毫米级的高分辨率进行粒度分析，有可能揭示出沉积物供应的季节变化和年际变化。本研究亦可为其他河口的相关工作提供借鉴。     

Hydrocarbon Potential of Pre-cenozoic Strata in the North Yellow Sea Basin

The North Yellow Sea Basin ( NYSB ), which was developed on the basement of North China (Huabei) continental block, is a typical continental Mesozoic Cenozoic sedimentary basin in the sea area. Its Mesozoic basin is a residual basin, below which there is probably a larger Paleozoic sedimentary basin. The North Yellow Sea Basin comprises four sags and three uplifts. Of them, the eastern sag is a Mesozoic Cenozoic sedimentary sag in NYSB and has the biggest sediment thickness; the current Korean drilling wells are concentrated in the eastern sag. This sag is comparatively rich in oil and gas resources and thus has a relatively good petroleum prospect in the sea. The central sag has also accommodated thick Mesozoic-Cenozoic sediments. The latest research results show that there are three series of hydrocarbon source rocks in the North Yellow Sea Basin, namely, black shales of the Paleogene, Jurassic and Cretaceous. The principal hydrocarbon source rocks in NYSB are the Mesozoic black shale. According to the drilling data of Korea, the black shales of the Paleogene, Jurassic and Cretaceous have all come up to the standards of good and mature source rocks. The NYSB owns an intact system of oil generation, reservoir and capping rocks that can help hydrocarbon to form in the basin and thus it has the great potential of oil and gas. The vertical distribution of the hydrocarbon resources is mainly considered to be in the Cretaceous and then in the Jurassic.