Metamorphic Segregation Banding in the Loch Kerry Basite Sheet from the Lewisian of Gairloch, Ross-shire, Scotland     

BOWES  D. R.; PARK  R. G. 《Journal of Petrology》1966,7(2):306-334

The Loch Kerry basite varies from amphibolite through stripedvarieties to strongly banded amphibolite containing many lensesof hornblendite and bands of plagioclasite. The striping andbanding is interpreted as the result of metamorphic segregationwith the complementary development of mafic and felsic types.The geochemical changes are set out and discussed on the basisof thirty-one new rock analyses. Foliation planes acted as pressure minima and differentiationdue to heterogeneous pressure led to the development of finelystriped amphibolite and subsequently to banded amphibolite.With continued deformation, the mafic parts of the banded assemblageacted passively while the felsic material moved along the foliationplanes. By preferential residual enrichment, hornblendite bandsup to 380 metres long and 30 metres across were formed. Theextent to which segregation progressed appears to have beencontrolled by the intensity of deformation in and adjacent toa zone of intense movement between a crystalline basement blockand cover rocks of basite and metasediment.  相似文献   

The Effect of the Irrigated Gudeuljang Paddy System on Biodiversity on Cheongsan-do (“island”)     

PARK Eunha  OH Choong-Hyeon 《资源与生态学报(英文版)》2016,7(3):218-222

This study has been conducted to identify the characteristics of the biodiversity promoted and maintained by gudeuljang paddy field. For this purpose, a literature review was used to identify the distribution of gudeuljang paddy field on Cheongsan-do. Based on the results of the review, a target area was selected to conduct an investigation of the flora of the vascular plants and a phytosociological examination, which included general farmlands and neighboring areas, was made for comparison. As a result of the study, we were able to identify the differences between the type of gudeuljang paddy field that uses continuous irrigation and other types of land use. We found that the unique physical structure for water passage found in gudeuljang paddy fields with continuous irrigation is more effective in promoting biodiversity than the other types of land use in this area. In conclusion, the presence of gudeuljang paddy fields on Cheongsan-do contributes more to the creation of an appropriate biohabitat than it detracts from such a creation. Also, the presence of gudeuljang paddy fields is significant in that it exercises positive influence on the promotion of biodiversity, such as propagation of species, and the connection of habitats in adjacent forest, village, and farm lands. Our result shows that the maintenance and preservation of gudeuljang paddy fields on Cheongsan-do plays a crucial part in the preservation and maintenance of the biodiversity for vegetation that grows among rocks and in adjacent forest areas.  相似文献   

集合同化方法在黄海海域海表面温度同化中的应用     

季轩梁  权径万  崔炳周  刘桂梅  朴光淳  王辉  卞道成  李云  纪棋严  朱学明 《海洋学报(英文版)》2017,36(3):37-51

The effects of sea surface temperature(SST) data assimilation in two regional ocean modeling systems were examined for the Yellow Sea(YS). The SST data from the Operational Sea Surface Temperature and Sea Ice Analysis(OSTIA) were assimilated. The National Marine Environmental Forecasting Center(NMEFC) modeling system uses the ensemble optimal interpolation method for ocean data assimilation and the Kunsan National University(KNU) modeling system uses the ensemble Kalman filter. Without data assimilation, the NMEFC modeling system was better in simulating the subsurface temperature while the KNU modeling system was better in simulating SST. The disparity between both modeling systems might be related to differences in calculating the surface heat flux, horizontal grid spacing, and atmospheric forcing data. The data assimilation reduced the root mean square error(RMSE) of the SST from 1.78°C(1.46°C) to 1.30°C(1.21°C) for the NMEFC(KNU) modeling system when the simulated temperature was compared to Optimum Interpolation Sea Surface Temperature(OISST) SST dataset. A comparison with the buoy SST data indicated a 41%(31%) decrease in the SST error for the NMEFC(KNU) modeling system by the data assimilation. In both data assimilative systems, the RMSE of the temperature was less than 1.5°C in the upper 20 m and approximately 3.1°C in the lower layer in October. In contrast, it was less than 1.0°C throughout the water column in February. This study suggests that assimilations of the observed temperature profiles are necessary in order to correct the lower layer temperature during the stratified season and an ocean modeling system with small grid spacing and optimal data assimilation method is preferable to ensure accurate predictions of the coastal ocean in the YS.  相似文献   

Physiological differences in the growth and maturation of Eisenia bicyclis and Ecklonia cava gametophytes in Korea     

Han Gil CHOI  Da Vine JEON  Seo Kyoung PARK  GAO Xu 《中国海洋湖沼学报》2019,(2)

The objective of this study was to examine the ef fects of temperature and light intensity on growth of female gametophytes of Eisenia bicyclis and Ecklonia cava and responses of these female gametophytes to Fe addition and daylength. Female gametophytes of each species were cultured at four temperatures(10, 15, 20, and 25°C) and under a combination of four light intensities(10, 20, 40, and80 μmol photons/(m 2 ·s)) with two temperatures(15 and 20°C for E i. bicyclis; 20 and 25°C for E c. cava) to clarify their optimal growth conditions. Growth and maturation of female gametophytes of these two species under a combination of five Fe-EDTA concentrations(0, 1, 2, 4, and 8 μmol/L) and three daylengths(10,12, and 14 h) were also examined. The growth of E i. bicyclis gametophyte was maximal at approximately15–20°C, 20 μmol photons/(m 2 ·s), Fe-EDTA concentration of 8 μmol/L and daylengths of 12–14 h. While E c. c ava gametophytes showed optimal growth at approximately 20–25°C, 20 μmol photons/(m 2 ·s), FeEDTA concentration of 8 μmol/L and daylength of 14 h. Maturation of gametophytes was enhanced at Fe-EDTA concentration of 4 μmol/L for E i. bicyclis and at 2 μmol/L for E c. c ava. In conclusion, optimal growth temperatures and Fe-EDTA concentrations for maturation of E i. bicyclis and E c. c ava gametophytes were dif ferent. Higher optimal growth temperature for E c. c ava gametophytes may contribute to its wider geographical distribution compared to E i. bicyclis which has restricted habitats in Korea. This suggests that addition of Fe ion could be used to recover beds of these two species in barren grounds of Korea.  相似文献   

Preliminary Results of the Ground-Based Orographic Snow Enhancement Experiment for the Easterly Cold Fog （Cloud） at Daegwallyeong during the 2006 Winter     

Myoung-Joo LEE  Ki-Ho CHANG  Gyun-Myoung PARK  Jin-Yim JEONG  Ha-Young YANG  Ki-Deok JEONG  Joo-Wan CHA  Sung-Soo YUM  Jae-Cheol NAM  Kyungsik KIM  Byung-Chul CHOI 《大气科学进展》2009,26(2):222-228

The snow enhancement experiments, carried out by injecting AgI and water vapor into orographically enhanced clouds (fog), have been conducted to confirm Li and Pitter’s forced condensation process in a natural situation. Nine ground-based experiments have been conducted at Daegwallyeong in the Taebaek Mountains for the easterly foggy days from January–February 2006. We then obtained the optimized condi- tions for the Daegwallyeong region as follows: the small seeding rate (1.04 g min-1) of AgI for the easte...  相似文献   

Statistical Downscaling for Multi-Model Ensemble Prediction of Summer Monsoon Rainfall in the Asia-Pacific Region Using Geopotential Height Field   总被引：16，自引：1，他引：15  

ZHU Congwen  Chung-Kyu PARK  Woo-Sung LEE  Won-Tae YUN 《大气科学进展》2008,25(5):867-884

The 21-yr ensemble predictions of model precipitation and circulation in the East Asian and western North Pacific （Asia-Pacific） summer monsoon region （0°-50°N, 100° 150°E） were evaluated in nine different AGCM, used in the Asia-Pacific Economic Cooperation Climate Center （APCC） multi-model ensemble seasonal prediction system. The analysis indicates that the precipitation anomaly patterns of model ensemble predictions are substantially different from the observed counterparts in this region, but the summer monsoon circulations are reasonably predicted. For example, all models can well produce the interannual variability of the western North Pacific monsoon index （WNPMI） defined by 850 hPa winds, but they failed to predict the relationship between WNPMI and precipitation anomalies. The interannual variability of the 500 hPa geopotential height （GPH） can be well predicted by the models in contrast to precipitation anomalies. On the basis of such model performances and the relationship between the interannual variations of 500 hPa GPH and precipitation anomalies, we developed a statistical scheme used to downscale the summer monsoon precipitation anomaly on the basis of EOF and singular value decomposition （SVD）. In this scheme, the three leading EOF modes of 500 hPa GPH anomaly fields predicted by the models are firstly corrected by the linear regression between the principal components in each model and observation, respectively. Then, the corrected model GPH is chosen as the predictor to downscale the precipitation anomaly field, which is assembled by the forecasted expansion coefficients of model 500 hPa GPH and the three leading SVD modes of observed precipitation anomaly corresponding to the prediction of model 500 hPa GPH during a 19-year training period. The cross-validated forecasts suggest that this downscaling scheme may have a potential to improve the forecast skill of the precipitation anomaly in the South China Sea, western North Pacific and the East Asia Pacific regions, wh  相似文献   

Experiment on Dust Flux During Duststorm Periods over Desert Area          下载免费PDF全文

ZHANG Hongsheng  ZHU Hao  PENG Yan  KANG Ling  CHEN Jiayi  Soon-Ung PARK 《Acta Meteorologica Sinica》2008,22(2):239-247

The present study investigates the characteristics of turbulent transfer and the conditions for dust emission and transport using the dust concentration and micrometeorological data obtained during dust events occurring in the spring of 2004 over the Hunshandake desert area. The turbulent exchange coefficients and turbulent fluxes of momentum and heat are calculated. The relationships between dust flux, friction velocity, and wind speed are also explored. The results show that thermal turbulence is dominant during daytime of non-dusty days. The dynamic turbulence increases obviously and the sensible heat flux reduces by different degrees during dust events. There is an efficient downward transfer of momentum before duststorm occurrence, and both the dynamic turbulence and the thermal turbulence are important in the surface layer. The dynamic turbulence even exceeds the thermal turbulence during severe duststorm events. The values of dust flux vary in the range of -5 5, -30 30, and -200-300 μg m^-2 s^-1 during non-dusty days, blowing dust, and duststorm events, respectively. A slight upward transport of dust is observed during non-dusty days. The dust flux gradually varies from positive to negative during duststorm periods, which indicates the time evolution of dust events from dust rising to stably suspending and then deposition. The dust flux is found to be proportional to u＊^3. The threshold values of wind speed and friction velocity are about 6 and 0.4 m s^-1, respectively.  相似文献   

Orbital‐ and millennial‐scale climate and vegetation changes between 32.5 and 6.9k cal a BP from Hanon Maar paleolake on Jeju Island,South Korea          下载免费PDF全文

JUNGJAE PARK  HYOUN SOO LIM  JAESOO LIM  KEUN BAE YU  JINMU CHOI 《第四纪科学杂志》2014,29(6):570-580

  相似文献   

Geochemistry of peridotite xenoliths in alkali basalts from Jeju Island, Korea   总被引：1，自引：0，他引：1  

SEONG HEE  CHOI  JONG IK  LEE  CHUNG-HWA  PARK  JACQUES  MOUTTE 《Island Arc》2002,11(4):221-235

Abstract   Ultramafic xenoliths in alkali basalts from Jeju Island, Korea, are mostly spinel lherzolites with subordinate amounts of spinel harzburgites and pyroxenites. The compositions of major oxides and compatible to moderately incompatible elements of the Jeju peridotite xenoliths suggest that they are residues after various extents of melting. The estimated degrees of partial melting from compositionally homogeneous and unfractionated mantle to form the residual xenoliths reach 30%. However, their complex patterns of chondrite-normalized rare earth element, from light rare earth element (LREE)-depleted through spoon-shaped to LREE-enriched, reflect an additional process. Metasomatism by a small amount of melt/fluid enriched in LREE followed the former melt removal, which resulted in the enrichment of the incompatible trace elements. Sr and Nd isotopic ratios of the Jeju xenoliths display a wide scatter from depleted mid-oceanic ridge basalt (MORB)-like to near bulk-earth estimates along the MORB–oceanic island basalt (OIB) mantle array. The varieties in modal proportions of minerals, (La/Yb)_N ratio and Sr-Nd isotopes for the xenoliths demonstrate that the lithospheric mantle beneath Jeju Island is heterogeneous. The heterogeneity is a probable result of its long-term growth and enrichment history.  相似文献   

Recent Advancement in Modeling Seafloor Dissipative Mechanism in Shallow Water     

Philip L.-F.LIU  Yong Sung PARK 《中国海洋工程》2008,22(1):1-10

In this paper, the recent development in modeling seabed dissipative mechanisms in shallow water is reviewed. Specifically, laminar and turbulent boundary layer solutions as well as viscous mud flow solutions under transient waves are presented. These analytical solutions are compared with experimental data for both solitary waves and cnoidal waves. Very goed agreement is ohtained. The Boussinesq equations with boundary layer effects and the muddy seabed effects are also shown.  相似文献