中国南海北部珠江口-琼东南盆地钻井岩屑地球化学特征及深水区天然气聚集特征     

高岗  张功成  陈果  刚文哲  沈怀磊  赵科 《海洋学报(英文版)》2018,37(2):44-53

The Qiongdongnan Basin and Zhujiang River(Pearl River) Mouth Basin, important petroliferous basins in the northern South China Sea, contain abundant oil and gas resource. In this study, on basis of discussing impact of oil-base mud on TOC content and Rock-Eval parameters of cutting shale samples, the authors did comprehensive analysis of source rock quality, thermal evolution and control effect of source rock in gas accumulation of the Qiongdongnan and the Zhujiang River Mouth Basins. The contrast analysis of TOC contents and Rock-Eval parameters before and after extraction for cutting shale samples indicates that except for a weaker impact on Rock-Eval parameter S_2, oil-base mud has certain impact on Rock-Eval S_1, Tmax and TOC contents. When concerning oil-base mud influence on source rock geochemistry parameters, the shales in the Yacheng/Enping,Lingshui/Zhuhai and Sanya/Zhuhai Formations have mainly Type Ⅱ and Ⅲ organic matter with better gas potential and oil potential. The thermal evolution analysis suggests that the depth interval of the oil window is between 3 000 m and 5 000 m. Source rocks in the deepwater area have generated abundant gas mainly due to the late stage of the oil window and the high-supper mature stage. Gas reservoir formation condition analysis made clear that the source rock is the primary factor and fault is a necessary condition for gas accumulation. Spatial coupling of source, fault and reservoir is essential for gas accumulation and the inside of hydrocarbon-generating sag is future potential gas exploration area.  相似文献   

典型湖泊天然有机质与四环素的相互作用     

曹驰程  王友权  章奇  张晖 《湖泊科学》2018,30(4):1004-1011

采用荧光滴定法研究四环素(tetracycline,TC)与太湖溶解性有机质(dissolved organic matter,DOM)和玄武湖DOM的相互作用.三维荧光光谱结合平行因子分析显示,2个湖泊的DOM含有3个荧光组分:类富里酸组分C1、类色氨酸组分C2和类络氨酸组分C3.其中C2的荧光强度远高于C1和C3,是DOM的主要荧光组成.3个荧光组分与TC发生了不同程度的静态猝灭,特别当TC浓度为45.5μmol/L时,类蛋白组分的荧光强度完全被猝灭(100%),并且猝灭作用改变了DOM分子的微环境极性.同步荧光光谱联合二维相关图谱进一步表明类色氨酸组分优先和TC发生猝灭作用,其次为类络氨酸组分和类富里酸组分.Ryan-Weber方程适于拟合DOM与TC的猝灭过程,2个湖泊的DOM中3个荧光组分的络合常数lg K值范围为5.05~5.85,大小顺序为C2C3C1.因此,类蛋白组分为主的DOM对TC的络合作用大于类腐殖组分为主的DOM,影响抗生素在湖泊水体中的生物有效性和生态毒性.  相似文献   

太湖五里湖水体悬浮物中水溶性有机质(WSOM)的荧光光谱组分鉴别及其与氮形态的关系   总被引：2，自引：2，他引：0  

张博  王书航  姜霞  黄晓峰  王雯雯 《湖泊科学》2018,30(1):102-111

采用三维荧光光谱-平行因子法(EEMs-PARAFAC)分析太湖五里湖水体悬浮物中水溶性有机质(WSOM)的荧光光谱特征,研究其组分类型、分布规律以及来源,进一步探讨悬浮物中水溶性有机氮和无机氮含量与WSOM荧光组分之间的关系.结果表明,悬浮物中WSOM荧光组分主要由2个类腐殖质(C1、C2)和1个类色氨酸类蛋白质(C3)组成.总荧光强度在57.56~200.01 R.U./g之间,平均为115.42 R.U./g,其中C1、C2、C3的相对比例分别为35.55%、34.05%和30.40%;空间上由西向东逐渐增强,东五里湖高于西五里湖,沿岸区高于湖心区.荧光指数和生物源指数变化范围分别在1.48~2.34和0.65~0.87之间,反映了悬浮物中WSOM主要来源于微生物、藻类的自生生物源.多元回归统计分析结果表明,悬浮物WSOM与氮元素的迁移转化密切相关,且有机氮与WSOM荧光组分的相关系数大于无机氮.  相似文献   

中全新世以来呼伦湖沉积物碳埋藏及其影响因素分析     

张风菊  薛滨  姚书春 《湖泊科学》2018,30(1):234-244

通过对内蒙古高原呼伦湖沉积物样品总有机碳含量(TOC)及其稳定同位素(δ13Corg)、总氮含量(TN)和TOC/TN(C/N)值的测定,结合沉积岩芯AMS14C年代标尺,分析了中全新世以来呼伦湖沉积物有机碳埋藏速率随时间变化的趋势及有机质的来源,并探讨了影响呼伦湖有机碳埋藏的主要因素.结果表明,中全新世以来呼伦湖有机碳埋藏速率平均值约为2.06 g/(m~2·a),碳储量约为35.25 Tg C,且总体上呈现增加趋势.呼伦湖沉积物中有机质主要来源于外源输入,但近1000 a以来内源输入逐渐增加并占据优势.呼伦湖有机碳埋藏速率与温度和降水均呈负相关,表明在长时间尺度上,升温及降水量的增加可能对呼伦湖的碳埋藏起到一定的抑制作用.  相似文献   

无磷条件诱导铜绿微囊藻(Microcystis aeruginosa)释放挥发性有机化合物对莱茵衣藻(Chlamydomonas reinhardtii)的影响     

杨王庭  赵静娴  徐庆欢  周律  甘丽平  左照江 《湖泊科学》2018,30(2):449-457

为了揭示磷(P)营养缺乏对蓝藻释放挥发性有机化合物(VOCs)的影响及其对其他藻类的化感作用,以形成蓝藻水华的主要种类铜绿微囊藻(Microcystis aeruginosa)为材料,在无P培养条件下对其释放的VOCs进行分析,同时测定VOCs对莱茵衣藻(Chlamydomonas reinhardtii)生长、光合色素含量和光合性能的影响.结果表明,采用无P培养基培养铜绿微囊藻24 h后,其释放的VOCs种类和含量均明显增加,与标准培养基培养相比,VOCs总释放量增加了73.4%,并出现7种新化合物.将铜绿微囊藻释放的VOCs通入莱茵衣藻溶液中,在标准培养基中铜绿微囊藻释放的VOCs对莱茵衣藻生长无显著影响,而无P条件下释放的VOCs则明显抑制莱茵衣藻生长,其响应指数(RI)为-0.25.此外,莱茵衣藻光合色素含量、光系统II(PSII)最大光化学量子产量(Fv/Fm)、有效光化学量子产量[Y(II)]、光化学淬灭系数(q P)和光合电子传递速率(ETR)也明显降低,而非光化学淬灭系数(NPQ)则明显升高,其RI为0.26.由此可见,蓝藻在富营养化水体中大量繁殖以及P自身沉降特性导致的P缺乏会促进蓝藻释放VOCs,同时这些VOCs在保持蓝藻营养竞争优势和水体藻类多样性减少中具有化感抑制作用.  相似文献   

Characteristics of Vegetation Carbon,Nitrogen, and C/N Ratio in a Tamarix chinensis Coastal Wetland of China     

Linping Xie  Baodong Wang  Ming Xin  Min Wang  Xiuping He  Qinsheng Wei  Xiaoyong Shi  Xia Sun 《洁净——土壤、空气、水》2019,47(9)

Variations in carbon (C) and nitrogen (N) of the vegetation in a Tamarix chinensis coastal wetland located in Laizhou Bay, China, are analyzed. It is found that T. chinensis accumulates more C and N than the surrounding herbs, and it allocates more C and N in the aboveground parts but less in the roots. Branches store more C, whereas leaves and flowers accumulate more N than other tissues. The C and N contents in the aboveground parts of T. chinensis are mainly influenced by pH, electrical conductivity (EC), water content, and clay content in the top 100 cm of soil as well as the distance from the sea. For the herbs, their C contents vary little in the supratidal zone, but they are higher than those in the intertidal zone. However, N contents in the herbs are higher in the aboveground parts and varied among different communities. The contents of C and N in the herbs are affected by EC, water content as well as the contents of organic C and total nitrogen (TN) in the top 10 cm of soil. The findings confirm that increasing the biomass of T. chinensis is an effective way to increase C sequestration in temperate coastal wetland.  相似文献   

Meio-epifaunal wood colonization in the vicinity of methane seeps     

Adriana Gracia C.  Lisa A. Levin  Sven Zea 《Marine Ecology》2020,41(1):e12573

In deep-sea environments, plant remains of several origins are found, including branches, twigs, leaves, and wood pieces, among others. As most of the deep-sea bottoms are oligotrophic and nutrient-limited, plant remains provide an oasis of localized organic enrichment and a substrate for colonization. Sunken wood was suggested to play an important evolutionary role in the diversification of chemosynthetic ecosystems, possibly representing stepping stones for the colonization between vent and seep ecosystems. In order to understand colonization processes of the Pacific Costa Rican meio-epifaunal assemblages associated with sunken wood, a field experiment was conducted on Mound 12 (8°55.778′N, 84°18.730′W) at ~1,000 m water depth. Woodblocks were placed in four different habitats (Mussel beds, tube worms, near mussel beds, rubble bottoms), and different local environmental conditions (seepage-active and seepage-inactive sites). Seven experimental Douglas fir woodblocks (each 1,047 cm² in surface area) were deployed from the R/V Atlantis using the manned submersible Alvin in February 2009 and recovered after 10.5 months in January 2010. Sample processing and analyses led to a data set of abundance (total 9,951 individuals) and spatial distribution of nine meio-epifaunal higher taxa/groups. Meio-epifaunal densities on individual woodblocks ranged from 3 to 26 ind.10 cm². Copepods accounted for the highest abundances (75.1%), followed by nauplii larvae (11.7%) and nematodes (9.8%). The maximum number of individuals (26.3 ind.10 cm⁻²) was found in blocks placed in seepage-inactive areas (near active mussel beds) in contrast to 2.9 ind.10 cm⁻² in active areas (within a mussel bed). A hierarchical cluster analysis grouped blocks according to seepage activity and not to habitat, but tests of similarity showed no significant differences in higher taxon composition and abundances, probably owing either to substrate homogeneity or low sample size. Copepods were the most abundant representatives, suggesting that this group is one of the most successful in colonizing in the early stage of succession, in this case while hardwood substrates are not yet decomposed or bored by bivalves.  相似文献   

长江口表层沉积物中正构烷烃的高分辨分布特征及有机碳来源解析     

王春禹  姚鹏  赵彬 《海洋学报》2020,42(10):1-13

于2014年3月对长江口及邻近海域的表层沉积物进行了高分辨率采样，分析了沉积物粒级组成、比表面积、总有机碳含量及其稳定碳同位素组成(δ13C)、正构烷烃及其相关分子指标，讨论了此区域沉积有机碳和正构烷烃的高分辨分布特征，并结合基于主成分分析?蒙特卡洛模拟的三端元混合模型，对沉积有机碳的来源进行了定量解析。结果表明，长江口及其邻近海域表层沉积物中总有机碳含量为0.45%±0.16%，近岸泥质区总有机碳含量较高，外海砂质区含量较低。总正构烷烃(C₁₄?C₃₅)的绝对含量和相对于总有机碳的含量分别为(1.42±0.73) μg/g和(0.34±0.21) mg/g。泥质区以长链正构烷烃占优势，具有较强的奇碳优势；砂质区以短链正构烷烃占优势，且具有一定的偶碳优势。长江输入、老黄河口输入、闽浙沿岸小型河流输入和水动力分选等因素制约了正构烷烃的输运和分布特征。模型结果显示此区域沉积有机碳来自海源、土壤和高等植物的混合输入，其中以海源为主，其贡献为42.70%±18.18%，由陆地向外海贡献逐渐升高，其次是土壤和高等植物，其贡献分别为28.99%±15.37%和28.31%±17.12%。在水动力分选作用的影响下，两种陆源有机碳在入海之后的输运过程中存在明显的分异，土壤有机碳主要与细颗粒物结合，并沿闽浙沿岸向南输运，而高等植物来源有机碳则在长江口存在东北方向的输运。  相似文献   

早渐新世钙质超微化石演变与营养盐及二氧化碳关系     

马瑞罡  杨海长  金晓波  赵钊  张功成  刘传联 《海洋学报(英文版)》2020,39(10):70-80

南海北部早渐新世发生明显的营养供给和二氧化碳浓度的变化，相关地质记录为研究颗石藻的生理机制提供了理想的自然实验室。在本研究中，我们建立了一个新的颗石藻群落演化的指标，定义为E*比值。该比值由富营养属种和中等-贫营养属种的相对丰度计算而得（E^*=e/(e+c)×100，e代表富营养属种，c代表中等-贫营养属种）。其中富营养属种包括小Reticulofenestra， Reticulofenestra lockeri组，Reticulofenestra bisecta组和Coccolithus pelagicus组，而中等-贫营养属种包括Cyclicargolithus spp.。E^*指标与早渐新世营养盐指标具有较强的相关性，但在不同二氧化碳浓度的条件下表现不同的公变趋势。将群落组合与已发表的二氧化碳浓度数据对比，我们提出颗石藻可能在二氧化碳持续降低的环境下改变其对碳源和营养盐的利用方式，指示颗石藻的碳浓缩机制可能开始于早渐新世。  相似文献   

白垩纪大洋缺氧事件研究进展     

范庆超  徐兆凯 《海洋科学》2020,44(2):138-145

系统总结了白垩纪OAEs的研究进展,重点讨论了OAE1a、OAE1b和OAE2时期的有机碳(TOC)含量、碳同位素、古温度和锶同位素特征及其古环境指示意义,综合分析了白垩纪OAEs的成因机制。结果表明白垩纪OAEs的发生可能与该时期海底大规模的火山活动以及由其引起的气温升高、碳水化合物大量分解、水文循环加快和海洋生物生产力提高等一系列变化有关。对于白垩纪OAEs演化特征和成因机制的深入研究具有重要借鉴意义。通过对白垩纪OAEs的综合分析发现,当前的研究区域主要集中在大西洋/特提斯盆地及其周边陆地,而对南半球高纬度地区的研究报道迄今未见,从而无法对白垩纪OAEs进行全球性对比和系统性研究。今后我们将重点围绕南半球高纬度地区白垩纪OAEs的演化特征、成因机制及其古气候环境效应等进行深入研究。  相似文献