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回顾与展望     
2007年恰逢勘探所建所50周年,回顾过去,勘探所自建所以来先后完成了科研成果近400项,在众多方面取得了突破性进展,有134项获部级以上奖励,其中获国家创造发明奖和新产品奖6项,国家科技进步一等奖1项,部、省科技成果一等奖7项、二等奖21项,其他各类奖项99项。获国家专利21项,为我国探矿(岩土钻掘)工程技术处于世界前列起了十分重要的作用。展望未来,勘探所面对新机遇和新挑战,必须紧紧围绕国务院《关于加强地质工作的决定》和温家宝总理对加强地质工作的重要指示精神,加大对钻掘新技术、新设备的研发和推广应用力度  相似文献   

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History     
《Geology Today》2000,16(5):170-171
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History     
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A.G.W. Cameron 《Earth》1973,9(2):125-137
A brief introduction is given to the various approaches which have been followed in attempting to construct models of the origin of the solar system. The author then outlines in more detail one of the more recent approaches, involving models of a massive primitive solar nebula. In this approach a massive gaseous disk is first formed during the course of star formation, and the Sun must subsequently form from the disk as a result of hydrodynamical dissipation processes. Both the dissipation and the accompanying formation of the planets are estimated to require only a few thousand years. As a consequence, there was little time for the Earth to radiate its energy of gravitational accretion, and the primitive Earth must have been extremely hot.  相似文献   

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A time table showing the history of the terrestrial planets is submitted in this paper. The planetary evolution is presented within the framework of global tectonics, whereby a distinction is made between exogenous and endogenous processes. Beginning with the age of 4.5 × 109 years and extending to the age of 3.0 × 109 years all terrestrial planets are characterized by a primordial-meteoric-vulcanic period. The development of the Moon and Mercury had been terminated with the end of this primordial period. Even until most recent times endogenous mantle processes and exogenous erosion processes shape the lithospheres on Mars, Venus, and the Earth. The Earth represents here the extreme case with highly dynamic plate tectonics. The degree of evolution of a planet is proportional to its mass. This leads to the following evolutionary scheme:
Zusammenfassung Eine Zeittafel zur Entwicklungsgeschichte der terrestrischen Planeten wird vorgelegt. Die Planetengeschichte wird in den Rahmen einer globalen Tektonik gestellt, wobei exogene und endogene Prozesse unterschieden werden. Von ca. 4.5 bis 3.0 × 109 Jahre werden alle terrestrischen Planeten von einer ur-meteorischen-vulkanischen Periode geprägt. Damit ist für den Mond und den Merkur die Entwicklung im wesentlichen abgeschlossen. Bei dem Mars, der Venus und der Erde formen bis in die jüngste Zeit endogene Mantelprozesse und exogene Erosionsprozesse die Lithosphäre, wobei die Erde den Extremfall mit einer hochdynamischen Plattentektonik repräsentiert. Der Entwicklungsgrad eines Planeten ist proportional seiner Masse. Das führt zu folgendem Entwicklungsschema:

Résumé Une table chronologique décrivant l'évolution des planètes terrestres est proposée dans cette publication. L'évolution des planètes est présentée dans le cadre de la tectonique globale, où distinction est faite entre processus exogènes et endogènes. Entre environ 4.5 et 3.0 × 109 années toutes les planètes terrestres sont caractérisées par une période primordiale-météorique-volcanique. Le développement de la Lune et de Mercure s'est terminé vers la fin de cette période primordiale. Dans Mars, Vénus et la Terre, les processus endogènes du manteau et une érosion exogène ont formé la lithosphère jusque dans les périodes les plus récentes; la Terre représente le cas extrème avec une tectonique de plaques à caractère dynamique très prononcé. Le degré d'évolution d'une planète est proportionnel à sa masse. Ceci conduit au schéma d'évolution suivant:

. , . 4,5 3,0×10–9 - . . , , , , . , . . :
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Doklady Earth Sciences - The results of comprehensive studies of bottom sediments and coastal transects in the Sea of Azov, obtained in recent years, have been analyzed. The changes in natural...  相似文献   

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The history-matching inverse problem from petroleum engineering is analysed using the Imperial College fault model. This fault model produces a challenging inverse problem and is designed to show some of the problems which can occur whilst performing history-matching calculations on complicated geologies. It is shown that there can be multiple distinct geologies which match the history data. Furthermore, it is shown that the maximum-a-posteriori estimate does not correspond to the true geology in some cases. Both of these statements are corroborated via numerical examples where the parameter spaces are ?, ?3, ?7 and ?13. In addition, it is shown that the number of matches which agree with the data increases with dimension for these examples. It is also shown that the different matches can result in different reservoir management decision which, if incorrectly taken, would incur substantial financial penalties. All of these analyses are performed in a systematic manner, where it is shown that the standard algorithms can give a misleading answer. The history-matching problem is written as a minimisation problem, and it is shown that knowledge of all of the local minima is required. This presents significant computational issues as the resulting objective function is highly nonlinear, expensive to evaluate and multimodal. Previously used algorithms have been proved to be inadequate. Parallel tempering is a method which, if run for long enough, can find all the local minima. However, as the objective is expensive, a number of algorithm modifications had to be used to ensure convergence within a reasonable time. This new information is outlined in the paper. The algorithm as implemented produced results and new insights into this problem which were not suspected before. The results produced by this algorithm for the multimodal history-matching problem are superior to all other results of which we are aware. However, a considered amount of computation time was used within this paper, so this result does not infer that the algorithm cannot be improved upon. This algorithm not only produces good results but can be applied to all other history-matching problems. We have shown that this method provides a robust route of finding multiple local optima/solutions to the inverse problem, which is of considerable benefit to the petroleum industry. Furthermore, it is an entirely parallel algorithm which is becoming computationally feasible for other history-matching problems.  相似文献   

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殷鸿福  喻建新  罗根明  宋海军  徐珍 《地球科学》2018,43(11):3809-3822
在地质历史时期的碳循环中,生物的作用很大.生物产氧光合作用消耗CO2而产生有机质与O2;有机质及生物成因碳酸盐岩埋藏又进一步固定CO2并减少O2消耗,所以生物产氧光合事件与冰期、成(增)氧期应存在因果关系.论述了5次事件,分别是:与产氧光合蓝细菌有关的古元古代初期大氧化事件(Early Proterozoic great oxygenation event,GOE)、与真核生物辐射事件有关的新元古代大成氧事件(Neoproterozoic oxidation event,NOE)、与早期陆生植物繁盛事件有关的晚奥陶世增氧和冰期事件、与维管植物繁盛事件有关的石炭纪-二叠纪增氧和冰期事件及与被子植物和浮游微植物繁盛有关的第四纪冰期事件.结果表明,5次成氧事件和冰期与生物事件有因果关系,主要表现为,都有冰期和成氧事件共存或相继出现的证据,反映大气CO2降低和O2增加同时或相继发生,而这只能由生物的光合作用及其产物的埋藏造成.这说明生物不仅仅是适应于环境,它也对环境产生重大影响,生物与环境的这种相互作用在漫长的地质历史中表现为协同演化.但是早期生物事件并不立刻产生成氧或冰期等环境效应,这种效应开始是微量的,逐渐积累,达到阈值后才发生质变,所以在时间上是滞后的.随着生物多样性和丰度的增加,这种效应越来越大,速率越来越快,滞后性逐渐减弱,耦合性日渐明显.生物与地球环境之间的相互作用构成了生物与地球系统的自我调节,使地球与其他星球不同,其表层始终保持在生命宜居的环境范围内.今天人类更要理智地、科学地善待地球,避免对地球造成重大的负面影响.   相似文献   

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火是地球系统的重要组成部分,与气候、植被、生物地球化学循环和人类活动密切相关。火对全球气候和生态系统的影响已成为目前全球变化研究的一个热点。火灾发生后会在周围的环境中留下许多燃烧产物,如黑碳、木炭屑、多环芳烃、左旋葡萄糖等,它们广泛存在于海洋、湖泊、河流、土壤和陆地风成沉积物中;还会留下一些火灾痕迹,如树木火疤、土壤磁...  相似文献   

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The early magmatic and tectonic history of the Carolina terrane and its possible affinities with other Neoproterozoic circum-Atlantic arc terranes have been poorly understood, in large part because of a lack of reliable geochronological data. Precise U-Pb zircon dates for the Virgilina sequence, the oldest exposed part, constrain the timing of the earliest known stage of magmatism in the terrane and of the Virgilina orogeny. A flow-banded rhyolite sampled from a metavolcanic sequence near Chapel Hill, North Carolina, yielded a U-Pb zircon date of 632.9 +2.6/-1.9 Ma. A granitic unit of the Chapel Hill pluton, which intrudes the metavolcanic sequence, yielded a nearly identical U-Pb zircon date of 633 +2/-1.5 Ma, interpreted as its crystallization age. A felsic gneiss and a dacitic tuff from the Hyco Formation yielded U-Pb zircon dates of 619.9 +4.5/-3 Ma and 615.7 +3.7/-1.9 Ma, respectively. Diorite and granite of the Flat River complex have indistinguishable U-Pb upper-intercept dates of 613.9 +1.6/-1.5 Ma and 613.4 +2.8/-2 Ma. The Osmond biotite-granite gneiss, which intruded the Hyco Formation before the Virgilina orogeny, crystallized at 612.4 +5.2/-1.7 Ma. Granite of the Roxboro pluton, an intrusion that postdated the Virgilina orogeny, yielded a U-Pb upper intercept date of 546.5 +3.0/-2.4 Ma, interpreted as the time of its crystallization. These new dates both provide the first reliable estimates of the age of the Virgilina sequence and document that the earliest known stage of magmatism in the Carolina terrane had begun by 633 +2/-1.5 Ma and continued at least until 612.4 +5.2/-1.7 Ma, an interval of approximately 25 m.yr. Timing of the Virgilina orogeny is bracketed between 612.4 +5.2/-1.7 Ma and 586+/-10 Ma (reported age of the upper Uwharrie Formation). The U-Pb systematics of all units studied in the Virgilina sequence are simple and lack any evidence of an older xenocrystic zircon component, which would indicate the presence of a continental-type basement. This observation, together with the juvenile Nd isotopic character of the Virgilina volcanic arc sequence, suggests that the oldest part of the Carolina terrane was built on oceanic crust away from a continental crustal influence.  相似文献   

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沉积盆地中未遭受热重置的碎屑颗粒裂变径迹(FT)热年代学正成为山前冲断带蚀源区抬升-剥露过程及其与相邻盆地沉积作用关系研究的重要方法.对于未热重置碎屑岩样品的磷灰石(或锆石)单矿物颗粒裂变径迹年龄(FTGA)数据,采用高斯或二项式拟合方法可以获得样品中不同组分碎屑颗粒矿物的FT峰值年龄或称蚀源区抬升一剥露事件的FT封闭(冷却)年龄.已有的统计分析结果表明,抬升冷却矿物的FT封闭年龄(tc)与其剥露搬运至相邻盆地的沉积年龄(td)之间具有较好的线性关系(tc=A+Btd),二者的滞后时间(△t=tc-td≈tc-te,te为抬升冷却的碎屑颗粒矿物剥露到近地表的剥露年龄)构筑了蚀源区抬升冷却矿物FT封闭深度(Zc)与抬升剥露速率(E)之间的定量关系(E=Zc/△t)和不同碎屑颗粒的滞后时间与其沉积年龄之间相关变化的统计预测模型△t=A+(B-1)td.显然,滞后时间越短,造山带蚀源区的抬升剥露速率越大、物源供应越充分,山前带沉积一沉降作用趋于增强,反之亦然.  相似文献   

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土层应力历史确定方法的研究   总被引:1,自引:1,他引:1  
本文通过粘土压缩的弹塑性模型,建立了不排水强度与超固结比的关系。针对海洋土在目前取样技术条件下受到较大扰动的现状,选择了受扰动影响相对较小的不排水强度推求先期固结压力。该法主要步骤为(1)临界状态孔压系数∧。的确定;(2)原位不排水强度的推算。通过南海东部某海域的原状土样和实验室制备的重构土样试验结果验证,此法确定的先期固结压力,与传统的方法进行比较,表明结果比较一致。  相似文献   

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Levente Füköh 《GeoJournal》1995,36(2-3):255-259
Based on phylogenetical, palaeoecological and biostratigraphical studies on the Holocene malacofauna of Hungarian medium high mountains and flatlands, four faunal periods could be recognised in the mountains, while three ones on the flat regions. They are defined by correlation (using anthracotomical, palynological, vertebrate palaeontological, archaeological and radiometric data, as well as by the Central European malacozones) as biozones of regional value.The mollusc fauna may be regarded as the main palaeoecological indicator for the Hungarian Quaternary, because it is generally abundant, in contrast to the vertebrate fauna. On the other hand, the Hungarian Quaternary fauna mostly consists of species still living in the area. The ecological demands of recent species are generally well known. Most of the ecological data about the Quaternary formations were yielded by the examination of the Hungarian mollusc fauna.The Quaternary mollusc fauna is not only suitable for palaeoecological reconstructions but it helps in the stratigraphical division of the sequences, as well, mainly due to Endre Krolopp's activity (Krolopp 1983). This study and investigations of Holocene molluscs enabled us to make an attempt (Füköh 1990) in describing the history of the last ten thousand years.  相似文献   

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酒东盆地热演化史与油气关系研究   总被引:16,自引:3,他引:13  
任占利  刘池阳 《沉积学报》2000,18(4):619-623
酒东盆地是由两期不同性质、不同世代盆地叠合而成。早、中侏罗世-早白垩世为拉张盆地,第三纪以来为挤压坳陷盆地。酒东盆地现今地温梯度及大地热流值较低,分别为300℃/100m及51mW/m2。营尔凹陷中生代晚期地温梯度高于现今地温梯度,可达350~420℃/100m;新生代以来大幅沉降,地温梯度降低,烃源岩的热演化程度受现今地温场控制。盆地热演化史与油气关系研究表明营尔凹陷下白垩统赤金堡组烃源岩主生油期有两期,分别在早白垩世晚期及第三纪以来。下白垩统下沟组和中沟组烃源岩主生油期仅有一次,主要为上新世以来。营尔凹陷有良好的找油前景。  相似文献   

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