知识创新工程重大项目在大庆油田的技术成果要览

在国家自然科学基金委员合和大庆油田的长期支持与资助下,我国陆相油储地球物理历经十余年的广泛探索,在理论认识上取得长足进步。据此,中国科学院第一批知识创新工程重大项目启动时,就以“油气勘探二次创业的前导研究”为题,列项研究。本文着重介绍在该重大项目推动下,近三年来参于大庆油气储量探到实践过程中,所摧熟的若干地球物理关键技术及软件系统功能。     

Distribution and accumulation of heavy metals in carbonate and reducible fractions of marine sediment from offshore mid-western Taiwan

Two marine sediment cores from offshore mid-western Taiwan were subsampled and pre-treated using a sequential extraction procedure to separate carbonate and reducible fractions. Aliquots of these extracts were analyzed to determine their chemical composition to evaluate the geochemical processes responsible for heavy metal distribution and accumulation in the coastal environment. Our data demonstrate that sedimentation rates derived from excess ²¹⁰Pb associated with metal fluxes show large increases circa A.D. 1990. A well-synchronized increase in metal flux in both geochemical fractions was found and validated by Pearson’s correlation. Principal component analysis revealed the heavy metal fluxes to be highly correlated with the sediment deposition rate, with metal contamination potentially driven by a sole contributor. This study emphasizes the changes in sedimentation rate is potentially caused by activities associated with the inland economic development during this time, rather than by raising heavy metal pollution dominated the accumulation offshore mid-western Taiwan.     

大庆电场地震实验资料的面波特征

通过对电场作用下的地震面波特征的研究，发现电场对地震面波的影响比对地震反射波的影响要大，这对进一步研究电场地震的机制有重要作用。     

A petrogenetic study of the garnet pyroxenite enclaves in spinel peridotite,North Dabieshan,China

Recently, garnet pyroxenite enclaves within peridotites occurring near Raobazhai, Huoshan County, have been discovered. The garnet pyroxenite is small pods, decimeters in size, enclosed within intensively serpentinized peridotites. Major mineral components comprise: garnet (Prp_25–35), sodium augite (Jd_10–25) with a small amount of ilmenite. There are two stages of retrometamorphism: the retrogressive granulite facies mineral assemblage is superimposed by that of amphibolite facies. The host rocks of the garnet pyroxenite are spinel peridotites, including spinel harzburgite and lherzolite. Due to intensive serpentinitization, only 5%–40% of the relic olivine (Fo_92–93) are preserved. The orthopyroxenes are Mg-rich (En_87–93) with bending of cleavages and granulation at their margins showing intracrystalline plasticity. On the basis of garnet-clinopyroxene Fe?Mg exchange equilibrium geothermometry proposed by Ellis & Green (1979) and Krogh (1988)K _D=4.06–5.28;T=793–919°C,P=1.5 GPa are estimated for the garnet pyroxenite. It is inferred that the peridotites are mantle rocks about 60 km in depth. During the exhumation of the orogenic belt, it was tectonically emplaced into the lower crust in the solid state and then uplifted to the shallow depth. Obviously, this kind of garnet pyroxenite must be petrogenetically related to its host rock. The REE distribution pattern and the Ni?Co?Sc diagram reveal that they are chemically equivalent to the basaltic melt and ultramafic residua respectively derived from partial melting of mantle rocks.     

河北省山区地质灾害气象预警系统

介绍了国内地质灾害预报预警方法研究及系统开发现状,阐述了河北省山区地质灾害气象预警系统的设计思路、系统构成、主要功能及特点.该系统利用河北省地质灾害区划信息、地理信息、气象观测和探测信息(稠密区域气象观测站降水、多种多普勒雷达产品、卫星云图、闪电定位等资料)、数值模式降水预报产品等,采用数理统计、天气动力学方法及计算机应用技术,可以方便快捷地生成预报预警产品.经2007年汛期业务应用证明,该地质灾害气象预警系统可以对地质灾害预报进行及时订正,减少空、漏报率.     

Decadal variation of surface solar radiation in the Tibetan Plateau from observations, reanalysis and model simulations

In this study, the annual and seasonal variations of all-sky and clear-sky surface solar radiation (SSR) in the eastern and central Tibetan Plateau (TP) during the period 1960–2009 are investigated, based on surface observational data, reanalyses and ensemble simulations with the global climate model ECHAM5-HAM. The mean annual all-sky SSR series shows a decreasing trend with a rate of ?1.00 Wm^?2 decade^?1, which is mainly seen in autumn and secondly in summer and winter. A stronger decrease of ?2.80 Wm^?2 decade^?1 is found in the mean annual clear-sky SSR series, especially during winter and autumn. Overall, these results confirm a tendency towards a decrease of SSR in the TP during the last five decades. The comparisons with reanalysis show that both NCEP/NCAR and ERA-40 reanalyses do not capture the decadal variations of the all-sky and clear-sky SSR. This is probably due to a missing consideration of aerosols in the reanalysis assimilation model. The SSR simulated with the ECHAM5-HAM global climate model under both all-sky and clear-sky conditions reproduce the decrease seen in the surface observations, especially after 1980. The steadily increasing aerosol optical depth (AOD) at 550 nm over the TP in the ECHAM5-HAM results suggests transient aerosol emissions as a plausible cause.     

寿县地区云中液态水含量的微波遥感

该文利用地基双频（22.235GHz（1.35cm）和35.3GHz（8mm））微波辐射计和热带降雨测量卫星微波成像仪（TRMM/TMI）两种被动微波遥感资料分别反演安徽寿县地区云中液态水含量，运用统计回归方法得到该地区云水含量的反演公式，揭示了该地区云中液态水含量存在一个阈值0.4mm，当云中液态水含量超过这一阈值时，该地区一般就会出现降水。在降水发生之前，水汽和云中液态水含量均会出现一个显著增加的过程，而在降水结束之后则会出现一个显著减少的过程。     

低纬高原地区城市化对室内外气温的影响研究

以低纬高原城市昆明市为研究对象 ,利用由于城市扩大而受到影响的昆明气象站室内外气温资料和未受城市影响的太华山气象站气温资料 ,以及城市建成区面积和城市人口资料 ,通过比较分析 ,得出以下结果 :昆明地区受全球气候变暖影响年平均气温约升高 0 .5℃ /3 0a ;由于城市面积扩大导致昆明的室内外气温均升高 ,其中室内气温升高幅度大于室外气温 ,干季大于雨季 ;不论是干季还是雨季 ,城市增温效应与城市建成区面积、城市人口均有较好的相关关系。城市建成区面积增加对平均气温的影响较大 ;而城市人口增加对平均室内气温的影响较大。城市建成区面积每增加 1km2 ,年平均室内气温将升高 0 .0 0 5 4℃ ;年平均气温升高 0 .0 12℃。而城市人口增加 1万人 ,年平均室内气温升高 0 .0 2 5 9℃ ;年平均气温升高 0 .0 0 98℃。以上结果有助于深入探讨城市化对城市气候的影响机制 ,为城市建筑的规划、设计提供一定的参考依据。     

IAP-AGCM对QBO模拟的动量收支分析

平流程准两年振荡(QBO)是赤道平流层(～100-1 hPa)变率的主要模态,可对中高纬地区的环流产生重要影响,但目前利用通用大气环流模式(GCM)对其进行准确模拟仍然是一个挑战.本文利用IAP大气环流模式(IAP-AGCM)的中高层大气模式版本(IAP-AGCML69)对QBO进行模拟,并对其动量收支情况进行分析.研...     

陆相高分辨率层序界面识别的地球化学方法

粘土矿物、微量元素普遍存在于各种类型的沉积物和沉积岩中,它们对环境的变化敏感,同时它们的沉积分异、组合特征、矿物成分及其含量都从不同的角度记录了形成过程中各种环境因素的变化。这些对恢复古环境,研究陆相湖盆水深变化具有重要的指示意义。通过对东营凹陷胜北断层下降盘沙三段 -沙四上段各层序内部高分辨率层序地层单元中岩石地球化学标型参数的研究发现,在一个高分辨率层序地层单元形成过程中,在古气候驱动下的湖平面变化旋回中,沉积岩中的矿物成分 (主要指粘土矿物和胶结物 )、化学成分 (微量元素 )等皆发生周期性变化。