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1.
本文通过对冲绳海槽D-086孔颗石藻化石的研究,自下而上划分出三个颗石藻化石组合:Gephyrocapsa aperta-G.oceanica组合,Gephyrocapsa ericsonii-Coccolithus crassipons组合,Emiliania huxleyi-Gephyrocapsa o-ceanica组合;划分出E.huxleyi带和E.huxleyi高峰带的界线;每一个颗石  相似文献   

2.
Relationshipbetweendeep-seafishdistributionsandoceanicconditionsoftheEastChinaSea¥ShenJin'ao(ReceivedNovember17,1993;accepted...  相似文献   

3.
游仆虫科下阶元系统关系的探讨(纤毛门,腹毛目)   总被引:7,自引:0,他引:7  
宋微波 《海洋与湖沼》1995,26(5):527-534
借助聚类分析和近祖演化推测(支序分类方法)对纤毛门原生运行中一高级类群-游仆虫科内各属间系统关系及科内地位予以分析探讨。结果建议:所涉各成员可细分为7个亚群,按演化顺序依次为Gastrocirrhus;Swedmarkia-Discocephalus;Uronychia;Diophrys;Euplotidium-Certesia;Cytharoides-Euplotes;Euplotaspis-A  相似文献   

4.
本文对冲绳海槽北部Rd-82孔浮游有孔虫N.dutertrei和Rd-86孔N.dutertrei及G.sacculifer的氧同位素记录进行了分析。Rd-82孔浮游有孔虫的氧同位素组成可清晰地划分氧同位素1-4期,跨越地质时代0-71ka;Rd-86孔可划分氧同位素1-4期及5a-5c亚期,跨越地质时代为0-110ka。  相似文献   

5.
A two-layers model for the summer circulation of the East China Sea   总被引:1,自引:0,他引:1  
Atwo-layersmodelforthesummercirculationoftheEastChinaSea¥LiangXiangsanandSuJilan(SecondInstituteofOceanography,StateOceanicAd...  相似文献   

6.
济阳坳陷下第三系颗石藻类化石的分布及与油气的关系   总被引:7,自引:1,他引:6  
系统研究了山东济阳坳陷下第三系颗石藻类化石的分布特征,发现该类化石平面分布广泛,在全坳陷的4个次级凹陷中均有分布,垂向上,主要分布在沙河街组一段和四段,含化石地层累积厚度近100m,颗石藻化石属种单一,主要为Reticulofenestra bohaiensis,该类化到零星和层状两种形式分布在钙质纹层页岩、泥岩和泥质白云岩中,通过与现代海洋沉积中颗石藻的分布特征相比较虱出济阳坳陷颗石藻化石纹层是  相似文献   

7.
此项研究所涉及的种主要为Noelaer habdaceae。本文采用Raffi等(1993)关于Gephyrocapsids形态特征的观点。用于分析的5个岩心取自南部大洋的大西洋和太平洋海区。PS2487_6岩心位于非洲角以南大陆坡DSDP360站位附近。由具泥质和超微化石互层的有孔虫软泥构成。PS2076_1岩样位于南极环极海流北部亚南极带厄加勒斯断裂带海岭脊部 ,接近于ODP1088站位 ,同位素和浮游有孔虫地层分析揭示为1—20海相同位素期(MIS)。PS2703_1、PS2708_1和PS2…  相似文献   

8.
由philodril、Arco(菲律宾)公司、PreussagEnergieGmbH、MMC勘探和生产(菲律宾)有限公司和BasicConsolidated公司组成的财团在苏禄海的Sandakan盆地中的Hippo-1井中发现天然气。预计可采储量为4...  相似文献   

9.
本文对冲绳海槽北部Rd一82孔浮游有孔虫N.dutertrei和Rd一86孔N.dutertrei及G.sacculifer的氧同位素记录进行了分析。Rd一82孔浮游有孔虫的氧同位素组成可清晰地划分氧同位素1一4期,跨越地质时代0一71ka;Rd一86孔可划分氧同位素1一4期及5a-5c亚期,跨越地质时代为0一110ka。根据氧同位素变幅分析,末次冰期极盛时冲绳海槽北部可能有黄河和长江的淡水影响,其影响强度Rd一82孔强于Rd一86孔。晚更新世以来,黑潮流一直影响着本区,冰期时黑潮流主流线向东转折段向南偏移,根据现有资料至少南移0.34个纬度。此外,在氧同位第2期,即末次冰期极盛期内发生一个短暂的气候回暖事件,该事件发生在21一20kaB,P,之间。  相似文献   

10.
欧洲中部晚冰期/全新世过渡期高分辨率的湖泊记录TomaszGoslar等Gosciaz湖(52°30′N、10°20′E、海拔64.4m)位于Vistulian冰川作用最大进积期冰盖的南部,最深处在湖的中心部位,另一个较深的部位在湖的西部,相互距离大...  相似文献   

11.
冲绳海槽北部表层沉积物中的钙质超微化石及其环境特征   总被引:4,自引:2,他引:4  
为探讨冲绳海槽表层沉积物中钙质超微化石的分布规律及其影响因素 ,对海槽北部槽坡区 ( 2 9°5 8.33′— 31°31 .2 3′N ,1 2 7°39.5 5′— 1 2 8°5 9.61′E) 34个表层样品进行了分析和研究。共发现 35种钙质超微化石 ,其中优势种为Gephyrocapsaoceanica、Emilianiahuxleyi和Florisphaeraprofun da ;G .oceanica、E .huxleyi等的百分含量变化和特征属种U .tenuis的出现 ,表明该区钙质超微化石组合面貌与东海外陆架相似 ,和东海及南海都属于北太平洋中央水团组合。G .oceanica的含量与海水营养盐存在一定的关系 ,但两者之间并不存在明显的正相关性 ;暖水分子U .irregularis、U .sibogae和O .fragilis的较高含量和冷水分子G .caribbeanica和Calcidiscusleptoporus的较低含量 ,进一步反映该区钙质超微化石的分布受到黑潮及对马暖流的影响 ,其中温度、盐度和表层海水结构性质 ,如海水透明度等因素可能为主要控制因素。  相似文献   

12.
末次冰消期以来苏拉威西海颗石藻化石记录与古海洋变化   总被引:1,自引:0,他引:1  
通过对苏拉威西海MD98-2178柱状样(3.62°N、118.70°E)颗石藻化石属种相对含量的统计,重建了2万年来海水古生产力、营养跃层的变化。其中Emiliania huxleyi、Gephyrocapsa oceanica、Florisphaera profunda占颗石藻群落的80%~90%。由于G.oceanica与F.profunda存在于两种完全不同的生态环境中,两者的变化趋势完全相反。前者代表高生产力以及高营养物质的海水,后者则代表低生产力与较深的营养跃层。推测冰消期颗石藻对环境变化具有两种响应模式:以约13.5ka的生产力峰值期为界,13.5ka之前颗石藻古生产力变化主要响应于径流对海洋营养物质的输入,而13.5ka之后则主要响应于海水-大气之间水循环的强度。全新世F.produnda含量及其所反映的营养跃层变化具有明显的百年尺度波动,与太阳活动的100~260a周期具有良好的相关性。推测全新世苏拉威西海区营养跃层变化受百年尺度的类似厄尔尼诺-南方涛动(El Nino-Southern Osillation,ENSO)的变化及太阳活动的驱动。  相似文献   

13.
通过对南沙海域表层沉积及活塞钻孔中颗石藻化石相对丰度和属种分异度的分析,得出颗石藻的组合面貌,并讨论了影响颗石藻组合的环境因素及晚更新世以来的气候变化。  相似文献   

14.
Distribution of dominant species and abundance of nannofossils in surface sediments of the central and northern partsof the S...  相似文献   

15.
本文研究了南海北部31孔岩芯样的长链烯酮化合物的分布与微体古生物(钙质超微化石和浮游有孔虫)的关系。烯酮化合物主要来自定鞭金藻的赫胥黎艾氏石Emilianisahuxleyi,其中C37∶2Me含量在31%~70%。应用C37的不饱和比值(U37k)计算了南海31孔柱状样的海水古温度,波动幅度在23.2~28.3℃之间,平均为25.3℃,低于该海域海水实测年平均温度(28.1℃)。U37k值的变化与浮游有孔虫壳体的氧同位素值分期有着对应的关系,亦可相应分成5期。  相似文献   

16.
南海西部表层沉积中的钙质超微化石   总被引:8,自引:0,他引:8  
分析研究了南海西部308个表层沉积样品中的钙质超微化石,发现除一个样品外,所有样品均含有钙质超微化石,但相对丰度相差悬殊,在0-1725个范围内变化。钙质超微化石在平面上的分布具有较明显的分区性,可划分为3个区。超微化石组合与南海其它地区超微化石组合面貌相似,由15属23种组成,以Gephyrocapsa oceanica,G.spp.(small),Emiliania huxleyi和Florisphaera profunda为优势种,占90%以上,其中Florisphaera profunda为绝对优势种。本调查区超微化石的分布受多种因素的综合影响,重点讨论了水深、陆源物质的稀释作用、碳酸盐的溶解作用以及重力流的沉积作用等因素对超微化石分布的影响,并根据超微化石的分布推断碳酸盐临界补偿深度(CCrD)约为3100m,碳酸盐补偿深度(CCD)大于4300m。  相似文献   

17.
Living coccolithophores(LCs) are regarded as a group of calcifiers and play important roles in global carbon cycle.This study used microscopic observations of LCs in the western Pacific Ocean to investigate their community structure and biodiversity,especially to test whether local physical traits(mesoscale eddies) could explain their biogeographic distributions during autumn of 2017.The coccolithophore calcite inventory based on carbon-volume transformation was estimated in this study.A total of 28 taxa of coccospheres and 19 types of coccoliths were identified from 161 samples.Gephyrocapsa oceanica was the most predominant species in all the coccolithophore community,followed by Florisphaera profunda,Emiliania huxleyi,Umbilicosphaera sibogae,Gladiolithusflabellatus and Umbellosphaera tenuis.The abundance of coccospheres and coccoliths ranged from 0 to 26.8×10~3 cells/L and from 0 to 138.5×10~3 coccoliths/L,averaged at 4.2×10~3 cells/L and 10.9×10~3 coccoliths/L,respectively.This study indicated that coccolithophore community in the survey area can be clustered into four groups.Three ecological niches of coccolithophores were characterized by their vertical profiles and multivariate statistical analysis.Coccolithophore abundance and species composition were remarkably different among warm-eddy region,G.oceanica dominated warm-eddy region,while F.profunda dominated warm-eddy and none-eddy region.The average values of estimated particulate inorganic carbon,particulate organic carbon were0.197 μg/L and 0.140 μg/L,respectively.The current field study widened the dataset of coccolithophores in western Pacific Ocean.  相似文献   

18.
长江南京段末次盛冰期以来的古河谷沉积   总被引:3,自引:0,他引:3  
末次冰期盛冰期海平面大幅度下降,长江发育古深槽。根据沉积物的颗粒状况,南京段古河谷的充填可以分为3期明显的由粗到细的沉积韵律:末次盛冰期深切古河谷,河床窄陡,沉积物颗粒粗,为卵砾石到中砂、粗砂;冰后期河床较宽,沉积物为砾石、粗砂到中砂、细砂;全新世,河流进一步展宽,沉积物为粗砂、中砂到细砂、粉砂,细砂沉积厚度很大。全新世中期河床有数次左右摆动,两侧形成了细砂—砂质黏土互层的沉积。根据不同时期沉积物的颗粒级配情况,推算出各时期河流的起动流速和平均流速,验证不同时期的沉积环境,认为剖面的深切河槽是局部深切的结果。各期河床形态和沉积物的特征,反映了末次盛冰期、冰后期、全新世的气候变化和环境演变。  相似文献   

19.
The living coccolithophores(LCs) are an important class of calcified taxa of phytoplankton functional groups,and major producers of marine biogenic inorganic carbon,playing an important role in the marine carbon cycle.In this study,we report the two-demensional abundance,composition of LCs and its correlation with the environmental parameters in spring and autumn,in order to understand the ecological role of LCs in the Yellow Sea and the Bohai Sea.In spring,totally 9 taxa belonging to coccolithophyceae were identified using a polarized microscope at the 1 000× magnification.The dominant species were Emiliania huxleyi,Gephyrocapsa oceanica,Helicosphaera carteri,and Calcidiscus leptoporus.The abundance of coccosphores and coccoliths ranged 0–7.72cells/m L,and 0–216.09 coccoliths/m L,with the average values of 0.21 cells/m L,and 11.36 coccoliths/m L,respectively.The Emiliania huxleyi distribution was similar to Gephyrocapsa oceanica.The highest abundance of coccoliths was observed in the east of Shandong Peninsula in northern Yellow Sea,whereas Helicosphaera carteri distributed more widely.Emiliania huxleyi and Gephyrocapsa oceanica were the two predominant species in LCs with higher abundances.The distribution of LCs was similar to that of coccoliths.In autumn,14 taxa belonging to coccolithophyceae were identified with dominant species as Emiliania huxleyi,Gephyrocapsa oceanica,Helicosphaera carteri,Calcidiscus leptoporus and Oolithotus fragilis.The abundance of coccosphores and coccoliths ranged 0–24.69 cells/m L,and 0–507.15 coccoliths/m L,with the average values of 1.47 cells/m L,and55.89 coccoliths/m L,respectively.The highest abundance of coccoliths was located in Qingdao coastal waters and south of the survey area.The distribution of LCs was similar to the coccoliths; in addition,LCs presented large abundance in the east of the central Yellow Sea area.  相似文献   

20.
Abstract. In Revellata Bay Gulf of Calvi, Corsica, France, the sparid fish Sarpa salpa L. is the main macro-consumer of Posidonia oceanica L. D elile leaf. Stomach contents were analysed and 13C/12C isotopic ratios were measured in fish muscle and potential food sources algae, P. oceanica leaf and its epiphytes to determine their relative contribution to the fish diet. S. salpa has an age-related mixed diet: juveniles are plankton feeders, young, sub-adults and adults are herbivorous, and, the older the individuals, the higher the relative contribution of P. oceanica to the diet. Our results and former studies of carbon stocks and fluxes in the P. oceanica bed of Revellata Bay have enabled an estimation of the general impact of S. salpa grazing on infralittoral communities: the studied species consumes 24 g C.m-2 -a-1 from P. oceanica leaf, 4.8 from epiphytes and 13 from epilithic algae. The fish net production and biomass turnover in that zone have been estimated to be 1.2gC.m-2.a-1 and 1.5 a-1, respectively.  相似文献   

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