Intensity distribution and effect of the Nov. 9, 1996 earthquake of Ms=6.1 in offshore outside the Yangtze River Mouth on the South Korea

On Nov. 9, 1996 at 21h56min (Beijing Time), an earthquake of MS=6.1 occurred in offshore outside the Yangtze River Mouth (31o43￠N, 123o04￠E). The shock affected Shanghai City and both Jiangsu and Zhejiang Provinces in China mainly. The shock was felt more strongly in the Yangtze River Mouth and Hangzhou Bay area than in the rest of them, particularly in high buildings of Shanghai City. In addition, the earthquake was felt in South Korea and also stronger in apartments or high buildings. LIU, JIN (1998) and LIU, et al (1999) described effect of the shock on the eastern China. The paper describes the effect of the earthquake on South Korea and the whole intensity distribution in South Korea and eastern China.     

龙岗复合陆块深部构造浅析

靖宇—和龙最新航磁ΔT⊥向上延拓5km等值线图和布格重力ΔgB资料,所反映深部地球物理场特征,具有良好的一致性。该区以金银别—露水河—天池存在的北北西向深部重磁变异带为界,可划分出两种不同的地球物理场区,表明该区龙岗复合陆块确实是由白山镇微地块与和龙微地块拼贴的产物。对地质—地球物理块体的进一步划分,还为认识古元古宙裂陷槽的展布及其后期地质事件带来一些具有启迪意义的重要信息。     

Thermal history of the Cretaceous Sindong Group, Gyeongsang Basin, Korea based on fission track analysis

ABSTRACT Apatite and zircon fission track (FT) analyses were carried out to reconstruct the thermal history of the Lower Cretaceous Sindong Group, which is the lowermost stratal unit of the Gyeongsang Basin, Korea. Zircon FT central ages show a wide range from 83 ± 5 to 157 ± 18 Ma, and single-grain age spectra have multiple age populations, whereas all apatites have very consistent FT ages of c . 60 Ma, suggesting a totally reset cooling age. Co-existence of both older and younger ages compared with the depositional age and relatively short mean track length indicate that the Sindong zircons were partially annealed. The Sindong Group was heated into the zircon partial annealing zone (ZPAZ) around 80 Ma, and cooled below the apatite closure temperature at c . 60 Ma. Based on the zircon FT results combined with vitrinite reflectance data, the maximum palaeotemperature to which the Sindong Group had been subjected can be inferred to be about 260 °C. Zircon FT data from a granite body that is in contact with the Sindong Group and sandstones close to the granite body indicate that thermal influence caused by Upper Cretaceous intrusive rocks was limited in close vicinity of the intrusion and that the major heat source of the Sindong Group was burial. The thickness of uplifted and eroded section is estimated to be about 7 km.     

Sulfur Isotope Study of Precambrian Basement and Mesozoic Intrusive Rocks in the Southwestern Part of Ryeongnam Massif, Korea

Abstract. Isotope composition of whole rock sulfur has been measured on 14 schists, 10 gneisses, 7 gabbroids, 7 granitoids and 2 sedimentary rocks, with of 9 sulfide (pyrite) sulfurs in gabbros and granitoids, from the southwestern part of the Ryeongnam Massif, Korea. The δ³⁴S values of schists range from -4.6 to +6.1 % (average +0.9 %), those of gneisses from -4.0 to +0.8 % (-1.9%), those of gabbroids from -2.3 to +3.7 % (+1.0 %), and those of granitoids from -5.9 to +3.2 % (-1.9 %). The δ³⁴S values of pyrite separated from gabbros and granitoids show rather heavier values ranging from +3.1 to +9.4 % with an average of+5.8%.
Though the δ³⁴S values of whole rock sulfur give wide range of -5.9 to +6.1 %, the average of about -0.5 % is close to the mantle value. The granitoids sampled at the central parts of intrusive bodies or at the contacts with other plutonic rocks tend to show positive values, while those sampled near the boundary with basement rocks such as granitic gneiss and por-phyroblastic gneiss show negative values. Though the reason of this tendency is not clear at present, the δ³⁴S values of some granitoids in this area seem to represent possible influence by the assimilation of country rocks, particularly of gneisses.
Average isotopic compositions of ore sulfur from individual metal deposits in the studied area are summarized to have a range of+1.0 to +7.8 % with an average value of+3.2 %. The values are consistent with the previous finding that the ore sulfur isotopic values of the Ryeongnam Massif are the lowest among the four tectonic belts in Korea; Gyeonggi Massif, Ogcheon Belt, Ryeongnam Massif, and Gyeongsang Basin. This feature may reflect the isotopic compositions of plutonic rocks and basements in this area, which are characterized by relatively low values around zero permil.     

The Kwinana Coastal Fumigation Study: I – Program Overview, Experimental Design and Selected Results

Fumigation under sea-breeze conditions is a major feature of the air pollution meteorology in the coastal industrial region of Kwinana, south of Perth in Western Australia. An intensive field experiment on fumigation was carried out in the region in early 1995 with the objective of using the measured data to develop and test a shoreline fumigation model. Fumigation of plumes from the Kwinana Power Station was studied using an instrumented research aircraft, radiosonde balloons, meteorological stations, a lidar, a mobile surface sampler, and sonic anemometers. The study has yielded a detailed and high quality data set as a result of both the range of observations undertaken and of the regularity of the sea-breeze conditions under scrutiny. The details of the experiment are summarised in this paper and some typical results are presented.     

The image of nature in geomancy

The art of geomancy (feng-shui in Chinese) is concerned with choosing auspicious sites from which man can benefit. Geomancy has been one of the most important ideas which influenced man's relationships with nature in East Asia and has significantly affected the location and morphology of cities, villages, houses and graves in China and Korea. In geomancy, nature is basically interpreted in terms of the following three images, namely: (1) magical, that which is produced mysterious power to influence man; (2) personified, that which is treated as functioning system of animate organism or inanimate object; (3) vulnerable, that which can be destroyed or recovered by human action.     

A METHOD OF LOCATING POLES OF THE STEREOGRAPHIC PROJECTION WITHOUT THE CURVED RULER

An instrument which has long been used in constructing the stereographicprojection of a crystal is the curved ruler suggested by both Wulff and Fedorowin 1893.~1 It is a convenient and quick method for drawing the flat arcs of verylong radius which cannot     

A Numerical Simulation on the Mesoscale Dynamics of the Spring Bloom in the Sea of Japan

The northward migration of spring bloom was observed in the Sea of Japan from April to May 1997 by the Ocean Color and Temperature Scanner (OCTS) on board the Advanced Earth Observing Satellite (ADEOS). This phenomenon is well simulated with a numerical ecosystem model coupled with a hydrodynamic model. The hydrodynamic model is the Geophysical Fluid Dynamics Laboratory (GFDL) Modular Ocean Model (MOM). The ecosystem model consists of five components: dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP), phytoplankton, zooplankton and detritus. Results of the numerical ecosystem model suggest that the mesoscale development of the spring bloom in the Sea of Japan is related to that of sea water temperature, and that the bloom is limited by the depletion of DIN. This revised version was published online in August 2006 with corrections to the Cover Date.     

Heat budget in the Japan Sea

The long-term mean (31-year mean) surface heat fluxes over the Japan Sea are estimated by the bulk method using the most of the available vessel data with the resolution of 1^o×1^o. The long-term annual mean net heat flux is about –53 W m^–2 (negative sign means upward heat flux) with the annual range from 133 W m^–2 in May to –296 W m^–2 in December. The small gain of heat in the area near Vladivostok seems to indicate the existence of cold water flowing from the north. In that area in winter, the mean loss of heat attains about 200 W m^–2, and the Bowen's ratio is over the unity. The largest insolation occurs in May in the Japan Sea, and the upward latent heat flux becomes the largest in November in this area. The heat flux of Haney type is also calculated, and the result, shows that the constantQ ₁ has the remarkable seasonal and spatial variation, while the coefficientQ ₂ has relatively small variation throughout all seasons. Under the assumption of constant volume transport of 1.35×10⁶ m³s^–1 through the Tsugaru Strait, the long-term averages of the volume transport through the Tsushima and Soya Straits are estimated to be about 2.20 and 0.85×10⁶ m³s^–1 from the result of the mean surface heat flux, respectively.