The 2011 Tohoku-Oki earthquake's influence on the Asian plates and Korean geodetic network

本研究分析了2011年3月11日发生的Mw9.0日本东北地区太平洋近海地震对亚洲地区和韩国国内GPS卫星常年跟踪站的位移影响.为此,利用了日本东北地区太平洋近海地震发生前后两周(2011年3月4日到3月18日)的GPS站点数据,包括震中附近地区(韩国,中国,中国台湾地区,日本和俄罗斯)55个GPS卫星常年跟踪站和284个IGS全球跟踪站,并采用GAMIT/GL,OBK软件进行处理和平差,估算出所有GPS站点的同震形变.结果显示,日本东北地区太平洋近海地震引起的同震形变影响在亚洲地区比较明显,包括日本和附近国家,距离震中2702 km的中国武汉(WUHN)站也观测到同震形变.为精确分析日本东北地区太平洋近海地震对韩国国家大地控制网的影响.通过GAMIT/GLLOBK软件计算出韩国GPS卫星常年跟踪站之间的基线长度变形,并分析出弹性变形量.结果表明:大部分GPS站点均向震中方向膨胀,且向震中的垂直方向收缩,由日本东北地区太平洋近海地震导致的最大剪应变达到韩国国家大地控制网年均变形率的约7倍,对韩国的地壳产生14.5～57.7 mm的水平位移,并导致韩国国家大地控制网产生弹性变形,因此,在不及时更新维护韩国国家大地控制网的情况下,GPS测量成果将会发生最大20 mm的位置误差.     

台湾北部四种软珊瑚体内十八种金属累积于共肉组织与中轴骨骼的特性

分别检测采自台湾北部和平岛沿岸海域及淡水河出海口海域的侧扁软柳珊瑚(Subergorgia suberosa)、扁刺柳珊瑚(Echinogorgia complexa)、网刺柳珊瑚(Echinogorgia reticulata)和1未定种柳珊瑚4种软珊瑚样品体内18种金属元素。比较同株珊瑚中金属累积于共内组织与中轴骨骼含量的特性．研究结果显示铜(Cu)及钒(V)于4种珊瑚中累积于中轴骨骼的量高于共内组织，Zn、Fe、Mn、Ca、Cd、Ni、Pb及Se则恰相反，Al、As、Co、Cr及Sn累积部位没有规则，Ag,Au及Ba因有ND值(未检出值)无法归纳其累积倾向，但若忽略ND值，则Ag与Ba累积于共肉组织较高，Au累积于中轴骨骼较高．此研究结果显示环境中金属倾向累积于软珊瑚共肉组织或中轴骨骼可能有一定之脉络可循．     

基于IGS跟踪站的高频GPS卫星时钟改正确定

利用IGS跟踪站的GPS观测数据,通过数据预处理,先求得对流层延迟参数,再解算高频(30 s)GPS卫星时钟改正,并与CODE(center for orbit determination in Europe)给出的30 s一笔的高频时钟数据进行比较,两者平均差异为0.003 234 ns,平均标准差为0.607 6 ns.通过比较,发现在20世纪90年代发射的Block IIA卫星携带的Cs钟不如Rb钟稳定和可靠,Block IIR卫星携带的时钟优于Block IIA卫星钟.     

Mechanisms and Processes Leading to Reverse Zoning in the Andong Granitoid Pluton, Andong Batholith, Korea

The Andong pluton consists of comagmatic granitoid rocks which constitute outstanding examples of reversely zoned granitoids. The pluton has three lithofacies: hornblende biotite tonalite, biotite granodiorite and porphyritic biotite granite. The zoned pattern forms by locating a tonalite core containing high-temperature mafic assemblages in central part,granodiorite rims in marginal part, and a porphyritic granite cap containing more felsic assemblages in topside of the pluton.Mineral abundances as well as bulk compositions of the granitoids indicate that the interior is enriched in mafic minerals and that it shows higher contents of oxides than the margin and topside. The compositional gradients change gradually with continuity between the lithofacies. The regular compositional variations within the pluton support the argument that the pluton behaved as an individual petrochemical system. Model abundances of the granitoids are in agreement with the bulk compositional gradients, suggesting that no significant interaction with country rocks occurred. Remobilization (resurgence) of deeper parts of the system into the more felsic magmas of the chamber explains the reverse zoning. Fractional crystallization was of importance and probably accounts for the selective removal of the settling phases. The Andong pluton is an example of reversely zoned plutons related by remobilization of more mafic but consanguineous magmas. Large-scale upwelling occurred in the pluton leading to the present arrangement of three lithofacies. It is conceivable that remnants of the reverse zoning become more difficult to discern as the plutonic rocks reach the latest stages of their evolution. In this case, the Andong pluton represents an earlier stage in the evolution of a felsic system that is usually represented by the final stages in normally zoned plutons.     

A multi-subwaveform parametric retracker of the radar satellite altimetric waveform and recovery of gravity anomalies over coastal oceans

The quality of satellite radar altimetric data is very important in studies of geodesy,geophysics,and oceanography.Over coastal oceans,altimeter waveforms are contaminated by the terrain and physical environments so that the accuracy of altimeter data is lower than that over open oceans.Here we develop a new multi-subwaveform parametric retracker(MSPR) to improve the quality of altimeter data for the recovery of gravity anomaly in coastal oceans.The least squares collocation method is used to recover the residual gravity anomaly over the coastal water from altimetric data.The waveform data records from Geosat/GM around Taiwan Island are practically retracked with MSPR.When compared with the Taiwan geoid height,the results retracked by MSPR are more accurate than those retracked by the well-known β-5-parmeter method and from the geophysical data records(GDRs).The gravity anomalies over Taiwan coastal waters are calculated from the retracked altimeter data with the least squares collocation.When we compared gravity anomalies computed using altimeter GDRs with the ship-borne gravity data over Taiwan coastal ocean,we found that the results from retracked data are more accurate than those from GDRs.     

西风带中槽脊的移动与发展的估计

本文考虑到西风宽度有限并存在急流,波动的南北宽度有限并其相对于急流轴的位置可有不同,以及槽脊热力结构的特征等因子,研究了槽与脊的移动速度,讨论了槽脊的发展问题。所得的结果经过试验与实际情况很一致,认为对槽与脊的移动发展的预报甚有实际应用意义。     

TiO2 nanoparticle trails in garnet: implications of inclusion pressure-induced microcracks and spontaneous metamorphic-reaction healing during exhumation

A new mechanism of cleaving-healing of garnet in metamorphic rocks during exhumation is reported. Almandine garnet with submicron multiple-phase inclusions characteristic of the GRAIL reaction, garnet + rutile = kyanite + ilmenite + low-quartz, was found by analytical electron microscopy to have non-epitaxial rutile nanoparticles distributed along internal {110} microcrack trails at the acute corner of submicron multiple-phase inclusions defined by the intersecting (110) and (011) mould surfaces. Such garnet microcracks were formed during lithostatic decompression due to a relatively high compressibility of quartz in the inclusion pockets and stress concentration at the acute corner. Spontaneous healing with accompanied formation of non-epitaxial rutile nanoparticles was activated predominantly via the GRAIL reaction due to high surface tension at the tip of microcracks and, to a lesser extent, decreasing lithostatic pressure or increasing inclusion pressure upon exhumation. This new mechanism of microcracking and healing involves stress build up, fracture propagation, mineral reaction, transport of elements to the reaction site and lowering of reaction boundaries by capillarity effect, all under the influence of thermodynamic and kinetic factors at the submicron-scale. Thus, TiO₂ nanoparticle trails in garnet provide additional information on the P–T path and may shed light on exhumation rates/mechanisms and metamorphic reactions/processes. Careful scrutiny of host minerals on the submicron scale is required to tell whether there are other metamorphic-reaction facilitated healing processes being overlooked by inappropriate techniques or being obliterated by the predominant healing processes of fluid infiltration and resorption zoning.     

台湾南湾秋末冬初浮游管水母类种类多样性和数量分布

2001年11月2—3日和12月8—10日在台湾南湾12个测站分别用2种锥形浮游生物网(网长 180cm,网口直径 45cm,筛绢网目孔径 333μm和 200μm)采集表层和底层(水深约50m)92份浮游动物样品。共鉴定出管水母31种,其中有7种是台湾周围海域新记录。舟状玫瑰水母Rosacea cymbiformis 为我国海域首次记录。爪室水母 Chelophyes appendiculata、巴斯水母Bassia bassensis、拟双生水母 Diphyes bojani、异双生水母 Diphyes dispar、小拟多面水母Abylopsis eschscholtzi 和扭歪爪室水母Chelophyes contorta 为优势种,它们分别占11月和12月管水母类总量的76%和63%以上。南湾管水母类的种类数和个体丰度均以 12 月(25种,1.99个·m-3)明显多于11月(19种,0.438个·m-3),这与12月外海高盐水团增强有关。大部分测站表层的种类和个体数多于底层。讨论了2种网型浮游生物网的采集效果,并比较了南湾与邻近海域同期管水母类种类数、丰度的季节变化和区系性质。     

Energy Consumption and Greenhouse Gas Emission of Korean Offshore Fisheries

This paper presents the energy and greenhouse gas(GHG) emission assessments of Korean offshore fisheries. The consumption of energy by fisheries is a significant concern because of its attendant environmental effect, as well as the cost of the fuel consumed in fishing industry. With the global attention of reducing GHG emission and increasing energy efficiency of fuel, the seafood industry needs to further understand its energy use and reduce its GHG emission. In the present study, the amount of energy consumed and the GHG emission of Korean offshore fisheries in a period from 2009 to 2013 were examined. Offshore fisheries accounted for 24% of Korean production in 2013 and 60% of fuel consumption related GHG emission. Whereas the total GHG emission intensity of this sector improved slightly between 2009 and 2012; as such emission decreased by approximately 1.9%, which increased again in 2013. The average amount of total GHG emission in this five years period was 1.78 × 10~6 tons of carbon dioxide equivalent/year(tCO_2eq. y~(-1)). Active fishing gear was found to consume 20% more fuel than passive gear. However, the production from passive gear was 28%, lower than 72% from active gear. The reason for this is that less abundant stationary resources are harvested using passive gear. Furthermore, the consumption of fuel was significantly influenced by the fishing method. Implementation and development of new fishing technologies and methods are important for improving energy efficiency and reducing the climate impact on fisheries. To realize these purposes, the fishery management system needs to be established by centralizing on energy efficiency and climate effect.     

由星载GPS双差相位数据进行CHAMP卫星动力学定轨

为了确定CHAMP卫星的轨道，由星载GPS数据和IGS跟踪站的GPS数据构造星地相位双差观测量，利用EOP、SGO、时间等数据，对GPS数据进行预处理，包括钟差改正、模糊度解算和周跳探测、卫星姿态改正、天线偏差和相位中心改正等，采用CHAMP卫星受力摄动模型，根据动力学原理，对CHAMP卫星进行实际定轨。与德国GFZ定轨结果PSO相比，本方法定轨结果径向精度为0．2857m。对于1d的重叠轨道，径向轨道差异的RMS为0．0958m。对于轨道端点比较，径向轨道差异平均为0．0666m。