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531.
文章系统分析了陆相生油理论和大庆油田的勘探实践,总结了大庆油田的勘探历程并划分为三大阶段:构造油藏勘探阶段,岩性油藏勘探的探索阶段,岩性油藏勘探大发展阶段。详细阐述了“十五”以来,大庆油田依靠创新理论与技术,丰富完善了大型陆相坳陷盆地岩性油藏勘探理论与配套技术,深层火山岩气藏勘探理论与配套技术,复杂断陷盆地油气勘探理论与配套技术,从而带来了松辽盆地北部中一浅层、深层和海拉尔盆地油气勘探的大发展,大庆油田再次进入油气储量增长高峰期。在详细分析大庆探区的勘探实际和资源潜力的基础上,提出了“百年油田”勘探的工作思路,通过扎实推进科学勘探,努力为油田可持续发展提供有力资源保障的勘探战略。 相似文献
532.
Ping Zeng Huiquan Chen Baichuan Ao Ping Ji Xiaojian Wang Zhiliang Ou 《Coastal Engineering》2002,44(4)
A numerical and experimental modeling is presented for studying the transport of waste heat from a nuclear power plant into coastal water by using a full-field physical model with scale distortion, a local physical model with normal scale and a depth-averaged k− turbulence model with a modified second-order upwind scheme. Field investigations are also used to provide the calibration and validation of the modeling. A case study simulating the turbulent tidal flow and waste heat transport in the coastal water near Daya Bay Nuclear Power Plant in Southern China was conducted. The experimental result of the case study shows that the water temperature in coastal water was a little oversimulated near the surface and was a little undersimulated near the bottom of heated-water layer by the full-field physical model. The numerical study shows that the depth-averaged k− turbulence model presented a satisfied prediction of turbulent tidal flow and far-field temperature distribution in coastal water, although the near-field stratification due to the heated water effluent was not accounted for. The result of the effect of scale distortion on physical model shows that a full-field physical model with a scale distortion of 10 produced a satisfied result of temperature distribution in the present case study. 相似文献
533.
C. Santinelli G. P. Gasparini L. Nannicini A. Seritti 《Deep Sea Research Part I: Oceanographic Research Papers》2002,49(12)
Vertical profiles of dissolved organic carbon (DOC) from eight hydrological stations in the Tyrrhenian Sea, Sardinia Channel and Algerian Sea, are reported. DOC exhibits concentrations ranging from 58 to 88 μM in surface water, 43–57 μM in the intermediate layer and 49–63 μM in deep waters. The assessment of the hydrological characteristics allows different water masses in the study area to be identified; moreover, different hydrological processes are observed in the Tyrrhenian and Algerian basins. DOC exhibits different values in the different water masses. The lowest DOC concentrations (43–46 μM) were found in the Tyrrhenian Levantine Intermediate Water (LIW). Correlations between DOC and apparent oxygen utilization (AOU), investigated within each water mass, exhibit different behaviors in the intermediate and deep waters, suggesting the occurrence of different processes of oxygen consumption in the different water masses. 相似文献
534.
Atlantic Water flow through the Barents and Kara Seas 总被引:2,自引:0,他引:2
Ursula Schauer Harald Loeng Bert Rudels Vladimir K. Ozhigin Wolfgang Dieck 《Deep Sea Research Part I: Oceanographic Research Papers》2002,49(12)
The pathway and transformation of water from the Norwegian Sea across the Barents Sea and through the St. Anna Trough are documented from hydrographic and current measurements of the 1990s. The transport through an array of moorings in the north-eastern Barents Sea was between 0.6 Sv in summer and 2.6 Sv in winter towards the Kara Sea and between zero and 0.3 Sv towards the Barents Sea with a record mean net flow of 1.5 Sv. The westward flow originates in the Fram Strait branch of Atlantic Water at the Eurasian continental slope, while the eastward flow constitutes the Barents Sea branch, continuing from the western Barents Sea opening.About 75% of the eastward flow was colder than 0°C. The flow was strongly sheared, with the highest velocities close to the bottom. A deep layer with almost constant temperature of about −0.5°C throughout the year formed about 50% of the flow to the Kara Sea. This water was a mixture between warm saline Atlantic Water and cold, brine-enriched water generated through freezing and convection in polynyas west of Novaya Zemlya, and possibly also at the Central Bank. Its salinity is lower than that of the Atlantic Water at its entrance to the Barents Sea, because the ice formation occurs in a low salinity surface layer. The released brine increases the salinity and density of the surface layer sufficiently for it to convect, but not necessarily above the salinity of the Atlantic Water. The freshwater west of Novaya Zemlya primarily stems from continental runoff and at the Central Bank probably from ice melt. The amount of fresh water compares to about 22% of the terrestrial freshwater supply to the western Barents Sea. The deep layer continues to the Kara Sea without further change and enters the Nansen Basin at or below the core depth of the warm, saline Fram Strait branch. Because it is colder than 0°C it will not be addressed as Atlantic Water in the Arctic Ocean.In earlier decades, the Atlantic Water advected from Fram Strait was colder by almost 2 K as compared to the 1990s, while the dense Barents Sea water was colder by up to 1 K only in a thin layer at the bottom and the salinity varied significantly. However, also with the resulting higher densities, deep Eurasian Basin water properties were met only in the 1970s. The very low salinities of the Great Salinity Anomaly in 1980 were not discovered in the outflow data. We conclude that the thermal variability of inflowing Atlantic water is damped in the Barents Sea, while the salinity variation is strongly modified through the freshwater conditions and ice growth in the convective area off Novaya Zemlya. 相似文献
535.
536.
初夏西北太平洋副高东西变动对中国南部降水东西差异的影响 总被引:1,自引:0,他引:1
西北太平洋副热带高压(以下简称副高)是影响中国气候的大尺度环流系统,为了进一步了解副高对中国气候的影响,本文利用站点观测资料和大气环流再分析资料,通过资料诊断分析和数值模拟方法,探讨了6月副高东西变动对中国南部降水的影响,以及影响副高东西变动的前期海洋因子.结果表明副高东西变动对中国西南和华南地区降水的影响明显不同:副高偏东有利于降水西南偏多而华南偏少,偏西则降水变化刚好相反.其原因与副高东西变化引起的环流差异有关,华南降水与副高东(西)变动时西太平洋地区副高西北侧的东北(西南)风异常以及东亚中低纬度地区异常经向波列的变化直接有关,而西南降水异常不仅与副高东西变动在东南亚地区引起的纬向风异常有关,与青藏高原大地形动力作用对副高北侧异常纬向风的变化也有十分密切的联系.此外,副高东西变动时影响西南和华南地区的水汽来源不同,影响西南的水汽主要来源于赤道印度洋80°E附近越赤道气流,而影响华南的水汽主要来源于副高南侧偏东气流从西北太平洋地区输送的水汽.进一步分析发现前期冬春季热带西北太平洋和赤道西太平洋海温变化的偶极差异与后期初夏副高东西变动有密切联系,冬春季西北太平洋暖海温和赤道西太平洋冷海温变化有利于后期初夏副高偏西,相反则有利于副高偏东,数值模拟结果在一定程度证实了资料诊断分析结果. 相似文献
537.
Previous observations have noted the change in albedo in a number of North Pole bright outliers and in the distribution of bright ice deposits between Mariner 9, Viking, and Mars Global Surveyor (MGS) data sets. Changes over the summer season as well as between regions at the same season (Ls) in different years have been observed. We used the bolometric albedo and brightness temperature channels of the Thermal Emission Spectrometer (TES) on the MGS spacecraft to monitor north polar residual ice cap variations between Mars years and within the summer season for three northern Martian summers between July 1999 and April 2003. Large-scale brightness variations are observed in four general areas: (1) the patchy outlying frost deposits from 90 to 270°E, 75 to 80°N; (2) the large “tail” below the Chasma Boreale and its associated plateau from 315 to 45°E, 80 to 85°N, that we call the “Boreale Tongue” and in Hyperboreae Undae; (3) the troughed terrain in the region from 0 to 120°E longitude (the lower right on a polar stereographic projection) we have called “Shackleton's Grooves” and (4) the unit mapped as residual ice in Olympia Planitia. We also note two areas which seem to persist as cool and bright throughout the summer and between Mars years. One is at the “source” of Chasma Boreale (∼15°E, 85°N) dubbed “McMurdo”, and the “Cool and Bright Anomaly (CABA)” noted by Kieffer and Titus 2001. TES Mapping of Mars’ north seasonal cap. Icarus 154, 162-180] at ∼330°E, 87°N called here “Vostok”. Overall defrosting occurs early in the summer as the temperatures rise and then after the peak temperatures are reached (Ls∼110) higher elevations and outlier bright deposits cold trap and re-accumulate new frost. Persistent bright areas are associated with either higher elevations or higher background albedos suggesting complex feedback mechanisms including cold-trapping of frost due to albedo and elevation effects, as well as influence of mesoscale atmospheric dynamics. 相似文献
538.
N. Mangold V. Ansan D. Baratoux F. Costard L. Dupeyrat H. Hiesinger Ph. Masson G. Neukum P. Pinet 《Planetary and Space Science》2008,56(7):1030-1042
Syrtis Major Planum is a volcanic plain dominated by lava flows. High resolution stereo camera (HRSC) images of the northern Syrtis Major region display erosional features such as grooves, teardrop-shaped islands and valleys. These landforms are characteristics of outflow channels seen on Mars, therefore implying that a flood event took place in this region. The flow of 100 km long and a few kilometer wide followed the local slopes in most locations. Maximum flood discharges estimated from images and topography vary from about 0.3×106 to 8×106 m3/s, and therefore are in the range of terrestrial mega-floods in the Scablands or Lake Bonneville. In North Syrtis Major, the relationships with surrounding lava flows and the timing of the flood coeval to Syrtis Major volcanic activity suggest that it could be related to the subsurface water discharge mobilized by the volcanic activity. The proximity of Noachian age basement rocks 20 km away from the flood and below lava flows might have played a role in its formation and water presence. 相似文献
539.
C.M. Lisse 《Icarus》2008,195(2):941-944
This response is to address the comments made by Drs. J. Crovisier and D. Bockelee-Morvan concerning the spectral analysis of Lisse et al. [Lisse, C.M., Kraemer, K.E., Nuth, J.A., Li, A., Joswiak, D., 2007. Icarus 187, 69-86] of the mid-IR ISO SWS spectrum of Comet Hale-Bopp 1995 O1 taken on October 6, 1996, and to support the conclusions made in Lisse et al. concerning the positive detection of PAHs in this comet. We also present some additional information determined from the Deep Impact and STARDUST missions, demonstrating the presence of PAHs in other comets, to support the plausibility of the Hale-Bopp PAH detection. 相似文献
540.
Comet 73P-B/Schwassmann-Wachmann 3 was observed with IRCS/Subaru at geocentric distance of 0.074 AU on UT 10 May 2006. Multiple H2O emission lines were detected in non-resonant fluorescence near 2.9 μm. No significant variation in total H2O production rate was found during the (3 h) duration of our observations. H2O rotational temperatures and ortho-to-para abundance ratios were measured for several positions in the coma. The temperatures extracted from two different time intervals show very similar spatial distributions. For both, the rotational temperature decreased from ∼110 to ∼90 K as the projected distance from the nucleus increased from ∼5 to ∼30 km. We see no evidence for OPR change in the coma. The H2O ortho-para ratio is consistent with the statistical equilibrium value (3.0) for all spatially resolved measurements. This implies a nuclear spin temperature higher than ∼45 K. 相似文献