Comparison among four kinds of data of sea surface wind stress in the South China Sea

By using remote sensing (ERS) data, FSU data, COADS data and Hellerman & Rosen-stein objective analysis data to analyze the sea surface wind stress in the South China Sea, it is found that the remote sensing data have higher resolution and more reasonable values. Therefore we suggest that remote sensing data be chosen in the study of climatological features of sea surface wind stress and its seasonal variability in the South China Sea, especially in the study of small and middle scale eddies.     

Magnetic anomalies in the canary basin and the Mesozoic evolution of the central North Atlantic

The data from a recent magnetic compilation by Verhoefet al. (1991) off west Africa were used in combination with data in the western Atlantic to review the Mesozoic plate kinematic evolution of the central North Atlantic. The magnetic profile data were analyzed to identify the M-series sea floor spreading anomalies on the African plate. Oceanic fracture zones were identified from magnetic anomalies and seismic and gravity measurements. The identified sea floor spreading anomalies on the African plate were combined with those on the North American plate to calculate reconstruction poles for this part of the central Atlantic. The total separation poles derived in this paper describe a smooth curve, suggesting that the motion of the pole through time was continuous. Although the new sea floor spreading history differs only slightly from the one presented by Klitgord and Schouten (1986), it predicts smoother flowlines. On the other hand, the sea floor spreading history as depicted by the flowlines for the eastern central Atlantic deviates substantially from that of Sundvik and Larson (1988). A revised spreading history is also presented for the Cretaceous Magnetic Quiet Zone, where large changes in spreading direction occurred, that can not be resolved when fitting magnetic isochrons only, but which are evident from fracture zone traces and directions of sea floor spreading topography.Deceased 11 November 1991     

减少航道外波浪集聚对策研究

进港航道开挖引起波能重新分布 ,导致航道外近区域波能聚集 ,波高增大 ,从而影响防波堤稳定及港内泊稳条件。文章介绍了 Boussinesq方程的推导过程和发展过程 ,基于深水和缓变地形的色散关系 ,建立了波浪数学模型。该模型可用于研究深水和浅水地区波浪的浅水变形、折射、绕射和反射。并提出了减少波能聚集、降低堤前波高的多种措施。结合大窑湾港实际工程 ,经过多方面的数物模比选 ,利用数学模型优化出一种可行的喇叭口航道开挖方案并付诸实施 ,降低了防波堤的堤前波高 ,满足了预期的设计要求。     

Modelling nitrogen and phosphorus cycles and dissolved oxygen in the Zhujiang Estuary Ⅰ.Model results

rmIoxThe averag annual dischaIge of the Zhujiang Xiver is 3. 32 x l0ll m3, which ranks theZhujiang River just end to the Changjiang River in China. The dischnye occutring duringthe fltal m between APril and ffepteTnber accounts for 80% of the yearly total. The Zhu-jiang hiver has a yeaIy sediment load of about 1 x l08 tons, which also concentrates in theM arn (Zhao, l990; Chen et al., 1998). The Zhujiang Xiver delta,which has l2 cities ofdifferent sizes and more than 40 towns with a po…     

威海地区高压岩石组合及其成因演化

利用矿物地质温压计估算变质高峰期温压条件、退变质作用温压条件。研究表明,本区为鲁苏构造带的北延部分,代表本区晚元古代华南陆块与华北陆块的碰撞及三叠纪华北陆块向华南陆块推覆事件的发生和演化。     

台湾海峡野生牙鲆人工育苗技术研究

报道了2004年3月对产自台湾海峡的野生牙鲆(Paralichthys olivaceus)进行人工育苗的研究结果。共获153万粒受精卵,孵出仔鱼140.8万尾,孵化率达92%,在育苗水温为20~24℃,海水盐度为26~31的条件下,经63 d培育,育出全长3.8~5.5 cm的幼鱼53.39万尾,成活率为37.9%。     

Jellyfish patch formation investigated by aerial photography and drifter experiment

Jellyfish patch formation is investigated by conducting a drifter experiment combined with aerial photography of a sustained patch of the moon jellyfish in Hokezu Bay, Japan. Jellyfish patches are aggregations of individuals that are caused by a combination of swimming (active influence) and advection by currents (passive influence). The drifter experiment involved the injection of 49 drifters around a distinct surface patch of jellyfish within an area of approximately 300 m × 300 m. The drifters’ motion, caused only by the passive influence, was recorded in a series of 38 aerial photographs taken over approximately 1 h. The ambient uniform current field larger than the patch scale was estimated from the movement of the centroid position of drifters, while the distribution of horizontal divergence and relative vorticity around the patch was estimated from the time-derivative in areas of triangles formed by the drifters. The centroid positions of both drifters and patches moved stably toward the bay head at different speeds. The difference vector between the patch and drifter centroids was directed to the sun, and was opposite to the ambient current. The distributions of vorticity and divergence around patches exhibited inhomogeneity within the patch scale, and the drifters in this nonuniform current field aggregated near the convergence area within 1 h. The results suggest that horizontal patch formation is predominantly influenced by passive factors at the surface of Hokezu Bay. Furthermore, the upward swimming against downwelling may make sustained patch in surface layer.     

Geodynamic Evolution of the Eastern Segment of the Azores-Gibraltar Zone: The Gorringe Bank and the Gulf of Cadiz Region

Detailed structural interpretation of the recently acquired deep seismic multichannel profiles along the Iberian Atlantic Margins (IAM Project) provides new results on the geodynamic evolution of the eastern part of the Azores-Gibraltar plate boundary. Thrusting and folding of the oceanic basement and of Mesozoic and Cenozoic sedimentary cover of the Gorringe Bank region are consistent with the N–S convergence of Iberia and Africa. Compressive structures in the Gorringe Bank region are spread over a wide area. Deformation under compression took place mainly in Tertiary times, as is evidenced by a basal unconformity and several discontinuities in Tertiary sediments, although some deformation has also been recorded in Quaternary sediments. The compressive structures in the Gulf of Cadiz are E–W oriented thrusts, folds and related diapiric structures. N–S oriented transpressive deformation is likely to occur in the western Portuguese platform. There is no continuity of structures from the oceanic to the continental domain, suggesting that deformation transfers from one side to the other through a transcurrent fault zone. The fault contact between the two domains is located in the ocean-continent transition zone.