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1.
东海陆架泥质区沉积地球化学比较研究   总被引:38,自引:4,他引:34  
利用东海陆架泥质沉积区和周围砂质沉积区的表层沉积物元素含量和海水悬浮沉积物总量分析资料,对泥质区的沉积地球化学进行了比较研究。结果表明东海不同泥质区的沉积地球化学过程很不相同。浙江近岸泥质区沉积物元素以Fe、Mn、Zn的含量高,Na、Sr、Al、Ca的含量低为特征,其地球化学特征与长江沉积物非常一致。近岸泥质区的沉积物基本来源于长江输入海的沉积物,在台湾暖流的作用下沉积在浙江沿岸。远岸济州岛西南泥质区沉积物以Na、Sr的高含量,较高的Al、Ca含量和低的Fe、Mn、Zn含量为特征,其地球化学特征与黄河源沉积物有好的相关性,但有一定的混合源性质,该泥质区的沉积物主要来源于黄河源的细颗粒沉积物,由黄海沿岸流搬运到该区并沉积下来。沉积物在搬运沉积过程中,元素粒度分异作用明显。东海陆架泥质区沉积地球化学过程的控制性影响因子是东海环流系统和物源,其中台湾暖流对东海陆架远岸和近岸泥质区的沉积地球化学分区具有关键作用。  相似文献   

2.
刘健  秦华峰  孔祥淮  李军 《第四纪研究》2007,27(6):1031-1039
黄东海陆架和朝鲜海峡等5个泥质沉积区全新世中期以来(自约6kaB.P.至今)的细粒沉积物主要是黄河、长江和朝鲜半岛的河流入海物质在复杂的海洋动力系统中的沉积产物.对取自山东半岛北部近岸泥质区和长江口以南的闽浙沿岸泥质区(舟山群岛近岸海区)的表层细粒沉积物(粘土质粉砂和粉砂质粘土)开展了详细的岩石磁学测试,包括磁化率、等温剩磁和样品磁化率随温度的变化等分析,并将实验数据与以往研究过的济州岛西南陆架区、南黄海东南部陆架区和朝鲜海峡西岸等3个泥质沉积区细粒沉积物的磁学特征进行比较研究.结果表明,上述5处细粒沉积物的磁性矿物主要组分为磁铁矿、磁赤铁矿和赤铁矿,其中低矫顽力磁性矿物为主,平均粒度为准单畴(PSD).根据磁性矿物的粒度和低矫顽力组分的相对含量,这5处细粒沉积物可以划分为3种类型:第1种类型是朝鲜海峡西岸细粒沉积物,其磁性矿物的粒度最粗,低矫顽力组分的相对含量为中等;第2种类型是南黄海东南部陆架细粒沉积物,其磁性矿物的粒度为中等,低矫顽力组分的相对含量最大;第3种类型是山东半岛北部近岸、闽浙沿岸(舟山群岛近岸)和济州岛西南陆架区的细粒沉积物,其磁性矿物的粒度最细,低矫顽力组分的相对含量最低.在这5处细粒沉积物中,闽浙沿岸(舟山群岛近岸)细粒沉积物的磁性矿物含量最高,其他4处细粒沉积物的磁性矿物含量都较低且大体相当.这种磁学特征的差异反映了物源的不同.从磁学特征来分析,济州岛西南陆架区的泥质沉积物主要来自黄河和长江;南黄海东南部泥质区的主要物源是朝鲜半岛进入黄海的河流,黄河和长江对其没有重要贡献.  相似文献   

3.
富含碳酸盐是黄河沉积物的主要特征之一。前人曾以碳酸盐作为黄河沉积物的特征成分或示踪成分来追溯黄河沉积物在中国渤海、黄海和东海陆架上的分布和影响,并用碳酸盐在细粒沉积物中的分布来显示黄河泥沙入海后的运移。黄河沉积物中碳酸盐的研究具有明显的学术价值和实用意义。本文着重研究了黄河三角洲沿岸及河口毗邻莱州湾海域的碳酸盐成分、含量和分布,探  相似文献   

4.
江苏王港潮间带表层碳酸盐的沉积特征   总被引:1,自引:0,他引:1  
利用容量法对江苏王港淤泥质海岸潮间带夏季表层沉积物碳酸盐的含量进行测定。结果表明,碳酸盐含量的空间分布呈现出由岸向海方向递减的大趋势;相关分析表明,总的碳酸盐含量与沉积物的平均粒径有比较显著的相关关系(α=0.01);沉积物组分及粒径频率曲线对比分析表明王港潮间带表层沉积物碳酸盐主要富集于细颗粒部分,潮水沟系统和生物作用(尤其是有孔虫)加强了碳酸盐在细颗粒部分的富集。沉积物碳酸盐含量可以作为物源分析的一个指标,王港地区沉积物碳酸盐含量表明该地区沉积物主要来源于废黄河三角洲和现代黄河的输入,长江输入的沉积物较少。  相似文献   

5.
东海表层沉积物中能反映东海油气藏异常的气、液、固相物质成分和物理化学参数可作为东海油气化探指标。本文讨论了东海表层沉积物间隙水、可溶铁和△C的油气化探指标。表层沉积物间隙水可作为海洋油气化探液态烃的样品源。根据油气藏顶部氧化还原环境的异常,圈出东海陆架盆地古滨海砂可溶铁Fe~(3+)/Fe~(2+)<1分布区作为油气远景区,提出了东海陆架盆地找油的新领域。△C是用无机组分反映油气富集的一种化探方法。东海陆架沉积物与△C有关的碳酸盐矿物主要是菱铁矿。  相似文献   

6.
通过中国地质调查局近20年对中国东部海域的高精度调查取样,对渤海、黄海和东海表层沉积物中的稀土元素数据进行了系统总结,旨在揭示其赋存特征、分布规律及其控制因素。结果表明,整个中国东部海域大致可以划分为4个稀土含量富集区,分别位于渤海西部泥质区、南黄海中部泥质区、济州岛西南泥质区以及东海内陆架泥质区,富集区内的表层沉积物稀土含量普遍高于180 mg/g;稀土元素的球粒陨石配分模式和UCC配分模式显示出各海域较为一致的总体特征,与中国大陆的稀土元素分配曲线类似,指示了较强的陆源特征。通过对稀土元素各特征参数的相关性分析,发现与中国东部海域稀土元素含量相关性最强的是δEu,呈明显负相关,其次是沉积物的平均粒径,呈明显正相关。利用δEu-(La/Yb) n物源判别图对这4个稀土含量富集区的样品进行判别,结果表明渤海西部泥质区和南黄海中部泥质区的沉积物具有同源性;南黄海东南部的济州岛西南部泥质区除了有来自长江和黄河物质以外,朝鲜半岛东南部的河流输入作用也不可忽视;东海内陆架泥质区北端的沉积物基本来源自长江,而南端则表现出不同的稀土分馏特征,很可能与闽浙沿岸和台湾岛中小河流的输入有关。大型河流和中小河流带来的物源、沉积物粒度以及海域流系格局控制了中国东部海域表层沉积物稀土元素的地球化学特征。  相似文献   

7.
黄龙  王中波  耿威  张勇  王明健 《地球科学》2020,45(7):2722-2734
利用X射线衍射,对东海东北部海域80个表层沉积物样品进行黏土矿物的相对含量分析.结果表明:东海东北部海域表层沉积物黏土矿物中伊利石(65.1%)含量最高,其次为绿泥石(26.6%)、高岭石(8.9%)和蒙皂石(4.3%);矿物组合中伊利石-绿泥石-高岭石-蒙皂石型占绝对优势,伊利石-绿泥石-高岭石型较少.由外陆架至冲绳海槽,伊利石含量分布呈低-高-低-高;绿泥石呈低-高-低;高岭石分布趋势明显异于伊利石和绿泥石,含量值分布出现由高到低的趋势;蒙皂石在个别区域缺失,高值区呈斑块状分布在水深小于100 m的外陆架.快速聚类分析显示,黏土矿物可分为“类长江”、“类黄河”和“类台湾”3种类型,呈4个区域相间展布.“类黄河”型黏土矿物主要由黄海沿岸流将黄河、废黄河等物质再悬浮搬运而来,分布于29.5°N以北、127°E以西的外陆架区,并未越过东海外陆架进入冲绳海槽.外陆架区“类长江”型黏土矿物主要为低海平面时期古长江物质,并混有少量现代长江源悬浮物质;冲绳海槽区“类长江”型黏土矿物主要来自低海平面时期古长江物质.“类台湾”型黏土矿物主要由黑潮控制,由台湾经冲绳海槽南部搬运而来,沿陆坡附近沉积.   相似文献   

8.
本文系统总结了中国东部近海沉积物中常、微量元素分布特征、控制因素及全新世以来的古气候沉积记录。指出表层沉积物中Si O2和Al2O3含量最高,两者可占沉积物总量的75%以上,而其他元素含量较低,且空间分布变化明显,主要受控于陆源物质输入、生物沉积作用、海洋化学沉积和成岩作用等因素。长江和黄河贡献了主要的陆源物质,非线性规划数学模型结果显示两者大致以123°E和32°N为南北向和东西向分界线,黄河物质控制了渤海和黄海大范围的区域,而长江物质则主要影响东海内陆架区域。东海内陆架泥质区南部的MZ01孔沉积物中CIA、Ba/Sr和Ca O/Mg O值指示了中全新世以来中国东部气候演化历史:8400~4200 a BP期间为暖湿期;4200~2300 a BP期间为波动变冷期;2300 a BP以来为持续的变暖期。功率谱分析表明太阳活动对中国东部古气候的周期性演化过程具有控制作用。  相似文献   

9.
依据“质量守衡”原理和沉积物物源难以穷尽的认识 ,提出了沉积物物源定量识别的非线性规划数学模型。利用该模型实现了东海陆架北部表层沉积物物源的定量计算 ,阐明了长江、黄河入海物质的大致分布特征。长江沉积物主要分布于 32°N以南、台湾暖流以西的海域 ,黄河沉积物主要分布于 32°N以北、台湾暖流以东的海域。长江、黄河两类沉积物的这种分布格局与本海域的流系分布相吻合。  相似文献   

10.
东海表层沉积物碎屑矿物组合分布特征及其物源环境指示   总被引:1,自引:1,他引:0  
张凯棣  李安春  董江  张晋 《沉积学报》2016,34(5):902-911
为进一步明确东海陆架区的沉积物物源及水动力环境,对研究区表层沉积物的碎屑矿物进行了鉴定分析。研究区共鉴定出49种重矿物、8种轻矿物。根据碎屑矿物的组合分布结合矿物形态特征,将东海陆架区划分为三个矿物区,内陆架矿物区、外陆架矿物区及虎皮礁矿物区。内陆架矿物区,动力分选是影响碎屑矿物分布的主要因素,物质来源相对单一,碎屑矿物主要来源于现代长江物质,闽浙沿岸近岸河流的输入,人类活动也对该区的矿物组成产生一定的影响;外陆架矿物区,重矿物分布的主控因素是长期的分选作用,主要是长江物质经后期改造形成,现代长江物质可从内陆架中北部扩散至124.5°E左右,此外外陆架东南部地形的变化也对碎屑矿物的分布起到一定控制作用;虎皮礁矿物区,有来自黄河、长江、火山物质的多重影响,且水动力环境相对复杂。  相似文献   

11.
东濮凹陷北部沙三中亚段广泛发育盐岩和烃源岩,这两个看似不能共存的物质却在这里互层共生。该时期研究区沉积特征为多盐韵律与多层烃源岩互层共生、连续沉积,单个盐韵律厚度从几米到十几米,烃源岩有机质丰度高、类型好。平面上,两者在湖盆沉积沉降中心共生;垂向上,高有机质丰度、好干酪根类型与高盐度地层具有较好的对应关系。因而成为恢复古气候和古环境的重要研究对象。通过岩石学、古生物学以及Sr/Ba、B/Ga、(V+Ni+Mn)、Fe/Mn、Sr/Cu、Mg/Ca、V/(V+Ni)、稀土元素含量和氯同位素等方法对凹陷北部沙三中亚段的沉积环境进行研究。结果表明,凹陷北部沙三中亚段为深水沉积的还原环境,古盐度较高,达到半咸水-咸水沉积;微量元素和孢粉化石特征表明研究区沙三中亚段为温暖潮湿的环境。  相似文献   

12.
In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning.  相似文献   

13.
郯庐断裂南段研究进展与断裂性质讨论   总被引:13,自引:3,他引:13  
据1:5万区域地质调查和专题研究资料,就郯庐断裂带是否南延与消失的原因,其与大别—苏鲁造山带交截形成的假位错效应,以及与中新生代沉积盆地形成演化的关系等作了新的阐述。在此基础上,讨论了郯庐断裂带是否为巨大的左行平移断层或转换断层。认为郯庐断裂带可能是在“古郯庐带”的基础上于早侏罗世重新活动、白垩纪强烈活动的地堑型枢纽断裂带。  相似文献   

14.
International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen.  相似文献   

15.
某高速公路下伏煤矿采空区稳定性分析   总被引:10,自引:0,他引:10  
在论述某高速公路下伏砦脖煤矿采空区地质、采矿和工程地质特征的基础上, 进行了稳定性数值模拟分析, 定性与定量地分析与评价了该煤矿采空区的地表变形特征及稳定性。研究结果表明: 该煤矿采空区的变形尚未完成, 对拟建的高速公路将产生很大的危害, 必须采取相应的工程治理措施。   相似文献   

16.
塘口水电站大坝基础座落在断层和裂隙较发育的龟裂纹灰岩上,岩体完整性差、透水性强,多年运行后,大坝灌浆廊道和排水廊道出现多处集中性漏水,为确保大坝安全和电站正常发电,根据渗漏性质和成因,采用对灌浆廊道补充帷幕灌浆,对排水廊道进行固结+帷幕+回填灌浆。通过灌浆处理后,效果良好,表明灌浆工程有效的将导致坝基渗漏的上下游的裂隙通道封闭,并顺利的经受了随后的汛期洪水考验,大坝安全得到保障。  相似文献   

17.
The Global Stratotype Section and Point (GSSP) for the base of the Silurian System was defined in 1985. Since that time, a number of researchers have suggested that this section has serious deficiencies for use as a GSSP. As a result, in 2000, the Subcommission on Silurian Stratigraphy (SSS) proposed undertaking a formal restu@ of this GSSP, which was subsequently approved by the International Commission of Stratigraphy (ICS). The result of this restudy was the formal proposal that the current GSSP, at 1.6 m above the base of the Birkhill Shale, at Dob's Linn, Scotland, should be maintained as the same locality and stratigraphic level, but the bios- tratigraphical definition of the boundary should be revised. The previously defined, basal Silurian grapto- lite zone, the Parakidograptus acuminatus Zone, should be subdivided into a lower Akidograptus ascensus Zone and a higher E acuminatus Zone. The base of the A. ascensus Zone, marked by the first appearance of A. ascensus, should be regarded as the biostratigraphic mark for the base of the Silurian. This proposal has now been formally approved by the SSS and ICS, and ratified by International Union of Geological Sciences. This is the first GSSP to undergo formal restudy and redefini- tion, and the proposal also included a recommended procedure for restudy of GSSPs.  相似文献   

18.
In reservoir characterization, the covariance is often used to describe the spatial correlation and variation in rock properties or the uncertainty in rock properties. The inverse of the covariance, on the other hand, is seldom discussed in geostatistics. In this paper, I show that the inverse is required for simulation and estimation of Gaussian random fields, and that it can be identified with the differential operator in regularized inverse theory. Unfortunately, because the covariance matrix for parameters in reservoir models can be extremely large, calculation of the inverse can be a problem. In this paper, I discuss four methods of calculating the inverse of the covariance, two of which are analytical, and two of which are purely numerical. By taking advantage of the assumed stationarity of the covariance, none of the methods require inversion of the full covariance matrix.  相似文献   

19.
It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T 3 = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″.  相似文献   

20.
正Artemia cysts are an extremely important component of aquaculture diets.It is well established that the cultivation of fish and shellfish derive substantial health and growth advantages when Artemia are included in the diets of the  相似文献   

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