沐官岛水库蓄水初期盐分运移数值模拟     

赵全升  鲁静  邵争平  高增文  冯娟 《水文地质工程地质》2008,35(4):6-10

沐官岛水库是一个拟建的河口海湾水库,库底为富含咸水的潮滩沉积物。这一特殊的地质及水环境条件直接关系到水库未来的水质安全和正常的调度运行,所以必须准确地确定水库水体中盐分空间分布这一关键问题。本文依据现场调查、钻探及室内实验资料,通过垂直方向线性插值技术,建立了沐官岛水库蓄水初期盐分运移准三维模型,模拟了水库蓄水初期在内源盐分释放影响下,库水盐分的演化过程。结果表明:若遇平水年开始蓄水,当蓄水至1.5m时,该层含盐量在平面上的变化范围主要在0.30~1.30g/L之间;当蓄水至4.5m时,该层含盐量在平面上的变化范围主要在0.30~1.55g/L。  相似文献   

山东莒南地质公园发现小型兽脚类恐龙足迹化石MinisauripUS     

李日辉  ;Lockley Martin G  ;Matsukawa Masaki  ;刘明渭 《中国区域地质》2008,(1):121-125

在山东省莒南地质公园内发现6个小型恐龙足迹化石,被归入足迹属Minisauripus。化石产于下白垩统大盛群田家楼组．时代为早白垩世巴列姆（Barremian）-阿普特期（Apdan）。5个较大,长约6cm,产于下部“主”层面上,其中4个组成2节行迹：1个较小,长约3cm,位于“主”层面30cm之上的上部层面上。山东Minisauripus的特征是：足迹个体小（长3．1～5．6cm,宽2．0～3．7cm）,三趾型,略不对称;足迹纵长,各趾近平行,趾垫较清晰;趾末端较钝,但爪迹较尖。Ⅲ趾比Ⅳ趾略长,而Ⅳ趾比Ⅱ趾略长且窄。此外,步幅较长,足长与步长之比约为10：1。与四川、韩国Minisau却淞不同之处是：足迹个体较大,长约是它们的2倍。继中国四川和韩国之后,山东是Minisau而淞在全球的第三个发现点。  相似文献   

东菲律宾海深水铁锰结壳发育站位沉积物的粒度及黏土矿物学特征          下载免费PDF全文

徐兆凯  李安春  蒋富清  刘建国 《海洋学报》2007,29(2):150-155

大洋铁锰结壳是潜在的重要海洋资源,多年来世界各国对此已作了大量调查.传统意义上的铁锰结壳均分布于3000m水深以浅的海山基岩上.中国科学院海洋研究所在对东菲律宾海的地质调查中采集到大量褐黑色深水铁锰结壳.在300多个站位的取样中,在44个站位采集到结壳样品,可见结壳在研究区的分布较为广泛.该结壳发育于4000~5000m水深的致密至半固结沉积物的表层,厚度一般为2~3cm,最厚可达7cm.结壳为板(层)状.  相似文献   

Vertical distribution of phytoplankton biomass,production and growth in the Atlantic subtropical gyres     

《Deep Sea Research Part I: Oceanographic Research Papers》2006,53(10):1616-1634

Ninety-four stations were sampled in the Atlantic subtropical gyres during 10 cruises carried out between 1995 and 2001, mainly in boreal spring and autumn. Chlorophyll a (Chl-a) and primary production were measured during all cruises, and phytoplankton biomass was estimated in part of them. Picoplankton (<2 μm) represented >60% of total Chl-a concentration measured at the surface, and their contribution to this variable increased with depth. Phytoplankton carbon concentrations were higher in the upper metres of the water column, whereas Chl-a showed a deep maximum (DCM). At each station, the water column was divided into the upper mixed layer (ML) and the DCM layer (DCML). The boundary between the two layers was calculated as the depth where Chl-a concentration was 50% of the maximum Chl-a concentration. On average DCML extends from 67 to 126 m depth. Carbon to Chl-a (C:Chl-a) ratios were used to estimate phytoplankton carbon content from Chl-a in order to obtain a large phytoplankton carbon dataset. Total C:Chl-a ratios averaged (±s.e.) 103±7 (n=22) in the ML and 24±4 (n=12) in the DCML and were higher in larger cells than in picoplankton. Using these ratios and primary production measurements, we derived mean specific growth rates of 0.17±0.01 d⁻¹ (n=173) in the ML and 0.20±0.01 d⁻¹ (n=165) in the DCML although the differences were not significant (t-test, p>0.05). Our results suggest a moderate contribution of the DCML (43%) to both phytoplankton biomass and primary production in the Atlantic subtropical gyres.  相似文献   

Sediment texture,distribution and transport on the Ayeyarwady continental shelf,Andaman Sea     

《Marine Geology》2005,216(4):239-247

The Ayeyarwady continental shelf is a complex sedimentary system characterized by large sediment influx (> 360 million ton/yr), a wide shelf (> 170 km), a strong tidal regime (7 m maximum tidal range), and incised by the Martaban Canyon. Grain size distribution on the Ayeyarwady shelf reveals three distinct areas in terms of sediment texture (i) a near-shore mud belt in the Gulf of Martaban and adjacent inner shelf (ii) outer shelf relict sands and (iii) mixed sediments with varying proportions of relict sand and modern mud in the Martaban Canyon. The bulk of the terrigenous sediment discharged by the Ayeyarwady River is displaced eastwards by a combination of tidal currents and clockwise flowing SW monsoon current and deposited in the Gulf of Martaban resulting in shoaling of its water depths. Part of the sediment discharge reaches the deep Andaman Sea via the Martaban Canyon and the rest is transported westward into the Bay of Bengal by the counter-clockwise flowing NE monsoon currents.  相似文献   

Measurements of suspended particulate matter with laser in-situ scattering and transmissometry in the Jiaozhou Bay in China     

WEI Jianwei  SHI Xuef  FANG Xisheng  ZHANG Weibin 《海洋学报(英文版)》2007,26(1):55-65

1 IntroductionKnowledge of suspended particle size and distri-bution is the key elements for better understandingthe sediment transport processes ( Wang et al.,2004), primary production (Ning et al., 2004),water quality controlling and pollution predictio…  相似文献   

东营凹陷王家岗地区王古1潜山构造特征及油气成藏条件     

侯方辉  李三忠  王金铎  于建国  吕海青  许淑梅 《中国海洋大学学报(自然科学版)》2007,37(2):341-344,322

进一步了解王古1潜山的构造特征及成藏条件,利用渤海湾盆地济阳坳陷东营凹陷王家岗地区的大量三维地震剖面和一些钻井资料,并结合东营凹陷南坡缓坡带区域构造背景及成藏条件分析认为,王古1潜山初始发育于印支期,后经燕山期拉张断陷,切割为断块并抬升,最后于燕山期定型,为典型的缓坡盆倾残丘潜山。该潜山被NW向和NE向断裂切割,潜山高部位侵蚀风化严重,上覆孔店组盖层及沙河街组烃源岩,油气通过断层和不整合面运移至潜山顶部形成侵蚀残丘型油气藏。  相似文献   

Coccolith distribution patterns in South Atlantic and Southern Ocean surface sediments in relation to environmental gradients     

《Deep Sea Research Part I: Oceanographic Research Papers》2006,53(6):1073-1099

In this study, the coccolith compositions of 213 surface sediment samples from the South Atlantic and Southern Ocean were analysed with respect to the environmental parameters of the overlying surface waters. From this data set, the abundance patterns of the main species and their ecological affinities were ascertained. In general, Emiliania huxleyi is the most abundant species of the recent coccolith assemblages in the study region. However, the lower photic zone taxa, composed of Florisphaera profunda and Gladiolithus flabellatus often dominate the assemblages between 20°N and 30°S. If E. huxleyi is excluded, Calcidiscus leptoporus and F. profunda become the most abundant species, each dominating discrete oceanographic regimes. While F. profunda is very abundant in the sediments underneath warmer, stratified surface waters with a deep nutricline, Calcidiscus leptoporus is encountered in high-productivity environments. Furthermore, the results of a canonical correspondence analysis reveal affinities of Gephyrocapsa spp., Helicosphaera spp. and Coccolithus pelagicus for intermediate to higher nutrient conditions in a well-mixed upper water column. In contrast, Gladiolithus flabellatus seems to be associated with high temperatures and salinities under low-nutrient conditions. Based on the relative abundances of Calcidiscus leptoporus, F. profunda, Gladiolithus flabellatus, Helicosphaera spp., Umbilicosphaera foliosa, Umbilicosphaera sibogae and a group of subordinate subtropical species, six surface sediment assemblages have been identified, which reflect the distribution and characteristics of the overlying surface waters. Their distribution appears to be mainly a function of the relative position of the nutricline and thermocline in the overlying photic zone.  相似文献   

北太平洋赤道海域表层沉积物的热释光特征及其指示意义          下载免费PDF全文

吕华华  石学法  吴永华  杨刚  魏建伟  王湘芹 《海洋学报》2007,29(3):162-171

热释光是矿物晶体接受环境核辐射作用后积蓄起来的能量在受到热激发时以光的形式释放出来的一种物理现象,它与晶体损伤、晶体中杂质混入等原因所导致的晶格缺陷有关.热释光强度的大小主要取决于自然界中长寿命放射性元素(238U,235U,230Th,40K及其子体)的衰变,与其他物理、化学、生物或人类活动无关.热释光特征能有效反映晶体形成的环境条件.热释光方法的制样简单、测量快捷,因此在辐射学、核工业、核医学、环境学、农业、考古学、地质学等领域都得到了广泛的应用.在陆地地质学上热释光方法在地质年代测定[1,2]、地层对比[3]、矿物世代划分[4]、矿床含矿评价[4,5]、陨石形成热的历史恢复[6]以及地质事件识别[7]等方面都取得了不少成果.  相似文献   

海洋重力测量数据处理系统MGDPS及其应用     

杨金玉  张训华  张志珣  杨慧良 《中国海洋大学学报(自然科学版)》2007,37(1):116-120

利用Delphi结合MapX开发的可视化船测海洋重力测量数据处理软件系统MGDPS,从专业角度详细论述了软件各模块的功能。使用实测数据对该系统进行了测试,实际应用表明,该系统具有准确可靠,易掌握,方便使用等特点,对我国海洋重力测量具有重要意义和使用价值。  相似文献