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1.
通过对南黄海北部14个站位的19个表层沉积物样品进行了粒度、有机碳、GC-FID和GC-MS-MS测定,探讨沉积物有机质中生物标志物组成特征及地球化学意义。研究区表明,沉积物有机碳含量较高,正构烷烃呈双峰分布,具有明显奇偶优势、平均L/H为0.36,说明沉积物中陆源高等植物贡献占优,分析对比表明其沉积物可能主要来自古黄河输入。类异戊二烯烃Pr/Ph均值0.46,表明有机质沉积于强还原环境;Pr/C17和Ph/C18值均小于1,并且随深度有减小的趋势,反映了研究区微生物的降解作用。甾类化合物C29豆甾烷>C(?)胆甾烷>C28麦角甾烷,说明萜类化合物和甾类化合物主要为陆相输入。较高OEP值、高丰度的藿烯和莫烷及甾烷S构型含量均反映了现代沉积物中有机质未熟-低熟特征,但由于原始母质影响和微生物发育,Ts/Tm和C31αβS/(S+R)、C32αβS/(S+R)、C33αβS/(S+R)和C29αββ/(ααα+αββ)值较高。  相似文献   

2.
长城湾及其附近沉积物中甾烷和萜烷化合物   总被引:2,自引:0,他引:2  
本文采用气相色谱和质谱联用技术,分析了长城湾及其附近沉积物中甾烷和萜烷化合物。C_(27)、C_(28)和C_(29)规则甾烷的丰度分布,以C_(29)甾烷的量最高,达47~52%。重排甾烷的存在表明,在成岩作用早期,在微生物的作用下,部分规则甾烷转变成重排甾烷。C_(29)降莫烷/C_(30)藿烷,C_(31)升莫烷/C_(30)藿烷,C_(31)22S/(22S+22R)和Tm/Ts等比值指出,沉积有机质处于中等成熟度,而且G9站较其他站沉积物含量高些。上述诸结果说明,生源母质来源于陆源高等植物,并混有一定量的生物物质。  相似文献   

3.
笔者由南大洋4个海洋沉积物样中,用有机试剂抽提有机质,经薄层色谱分离、气相色谱分析、色谱-质谱-数据处理系统联用仪鉴定,确定有17β(H)、21α(H)——双升莫烯,胆甾-5-烯,24-甲基胆甾烯,24-乙基胆甾烯,藿-17(21)-烯,新藿-13(18)-烯,蕨-8-烯,蕨-7-烯,17β(H)、21β(H)-藿-22(29)-烯,C27-29甾烷,β,β-C29-31藿烷,C18:2Δ9,12双烯脂肪酸,C18:1Δ9和C18:1Δ11单烯脂肪酸等有机化合物.这些有机物的有机地球化学意义为:β,α-双升莫烯、β,β-C29-31藿烷、β,β-藿烯等有机物标志着南大洋沉积物中有机质的成熟度低的特征;甾烯、甾烷的分布标志着南大洋沉积物中有机质在早期沉积作用中经受过热滤化特征;蕨烯和双烯脂肪酸等有机物可作为南大洋沉积物中的细菌的标志物,还可以作为南大洋沉积物中的还原环境标志物.  相似文献   

4.
以曹妃甸邻近海域为研究区,利用生物标志化合物地球化学参数分析了表层沉积物中石油烃类的主要组成和分布特征,探讨了石油烃污染物的来源。结果表明,曹妃甸邻近海域表层沉积物中正构烷烃为混源,且陆源贡献小于海洋源。地质构型藿烷、甾烷在甾萜类化合物中为优势组分,且萜甾烷参数显示了有机质成熟度较高。饱和烃的多种地球化学参数显示了该区域表层沉积物可能受到成熟度较高的石油烃输入及其后期微生物降解的影响。该研究将为曹妃甸近岸沉积物输移研究提供基础资料,进而为曹妃甸围填海工程的科学决策提供相关科学数据。  相似文献   

5.
长江口柱状沉积物中甾醇的组成特征及其地球化学意义   总被引:4,自引:0,他引:4  
吕晓霞  翟世奎 《海洋学报》2006,28(4):96-101
通过对长江口两个柱状沉积物中有机质的GC-MS分析,检出C27-C29甾烷醇、C27Δ5,C28Δ7和C29Δ22甾烯醇以及C30Δ22烯醇(4α,23,24-三甲基-5α-胆甾-22-烯醇)7种主要甾醇生物标志化合物.8站位沉积物中以陆源输入为主的C29甾醇的相对丰度最高,在17站位深层沉积物中也以C29甾醇为主,而其表层沉积物中则是以海洋浮游动物输入为主的C27甾醇的相对丰度最高.在所有的样品中甾醇都经历了较强的加氢还原作用,相同碳数的甾烷醇的相对丰度远远高于其相对应的甾烯醇的相对丰度.随着沉积深度的增加,甾烯醇的加氢还原作用越强,且由于两个站位不同的沉积环境,8站位甾烯醇的加氢还原作用更强.  相似文献   

6.
采用气相色谱-质谱技术对南极半岛东北海域海底表层沉积物的总有机碳、有机质碳同位素(δ13 Corg)和生物标志化合物等进行了测试分析。研究区表层沉积物总有机碳TOC平均值高于现代深海沉积物中的平均含量。δ13 Corg的变化说明该海域有机碳来源呈海洋水生生物来源和陆源混合的特征。正构烷烃的峰型分布、主峰碳、饱和烃轻重比C-21/C+22和(C21+C22)/(C28+C29)、甾烷组合和藿烷组合证实研究区西部表层沉积物有机质来源以陆源高等植物为主,其陆源可能来自于附近的南极半岛和南舍得兰群岛;研究区东部表层沉积物有机质来源偏以海源为主,且以低等浮游生物、藻类及细菌生物等海源输入为主。碳优势指数(Carbon preference index,CPI)、奇偶优势指数(Odd-even Predominance,OEP)和甾烷C29ααα20S/(20S+20R)比值显示研究区D1-7站位和D5-9沉积物有机质演化程度较高,D5-2和D2-4站位的有机质演化程度低,其他站位介于中间状态。饱和烃中姥鲛烷、植烷及其比值(Pr/Ph)等组合显示研究区西部以氧化-弱还原的沉积环境为主,其可能是受高温低盐别林斯高晋海水流和附近火山喷发的影响所致;研究区东部以还原—强还原沉积环境为主,可能是受低温高盐的威德尔底层水(WSBW)和威德尔海深层水(WSDW)影响所致。  相似文献   

7.
东营凹陷南斜坡原油生物标志物特征和油源对比   总被引:1,自引:0,他引:1  
对东营凹陷南斜坡沙四段油砂采样和高分辨率的GC-MS分析,研究了南斜坡沙四段原油的生物标志物特征,并且进行了油源对比,分析了原油成因.C29甾烷20 S/20(R S)和C29甾烷ββ/(αα ββ)参数显示纯化、乐安、广利、金家和王家岗部分样品为低成熟原油.小营、正理庄、高青和王家岗部分地区样品为成熟油原油.C27/C29>1反映广利、纯化和金家母源输入有低等水生生物输入,C27/C29<1反映王家岗、草桥、高青和小营地区母源有高等植物的贡献.原油中正构烷烃主要以奇数碳占优势,碳数分布为nC14-nC34,普遍存在生物降解,个别样品正构烷烃几乎消失殆尽.多数样品Pr/Ph<1,具有明显地植烷优势,伽马蜡烷/C30藿烷分布介于0.15~1之间,说明母源沉积环境为半咸水-咸水还原沉积环境.油源对比表明博兴地区的原油主要来自于博兴洼陷的沙三、沙四上段烃源岩.纯化油田油源主要来自于利津和博兴洼陷沙四上亚段,乐安、八面河、羊角沟、王家岗、广利油田的原油来自牛庄洼陷沙四上亚段.  相似文献   

8.
应用生物标志物参数定量判识热水沉积古环境   总被引:1,自引:0,他引:1  
利用气相色谱-质谱(GC-MS)对西成矿田泥盆系热水沉积岩和重庆城口震旦系正常沉积岩中的生物标志物进行了测定,并通过多元统计方法对两种环境中的多种生物标志物参数进行了聚类和判别分析。结果表明:(1)热水沉积岩和正常沉积岩中的有机质饱和烃/芳烃平均值分别为4.64和1.10,正构烷烃的碳优势指数CPI平均值分别为1.35和1.11,ΣnC22-/ΣnC22 为3.17和0.74,nC21 22/nC28 29平均值分别为4.29和1.61,Pr/Ph平均值分别为0.44和0.28,C29-/C30 平均值分别为7.41和0.98,C21/αβC30平均值分别为4.32和0.31。(2)热水沉积岩中的有机质具有高饱和烃、低芳烃,饱和烃馏分中低分子量生物标志物含量较高而高分子量生物标志物含量较低的特点。ΣnC22-/ΣnC22 和nC21 22/nC28 29可能反映西成矿田硅质岩形成时的特殊的热水沉积古环境,三环萜烷C21/αβC30藿烷值可能是热水沉积环境的一个较好的指标。(3)以ΣnC22-/ΣnC22 、nC21 22/nC28 29、Pr/Ph和C30αβ藿烷/ΣC29甾烷4个参数建立的两类判别函数可以定量判识热水沉积古环境。  相似文献   

9.
本文报道了爱丝湖沉积物中烃类的分布特征。经分析鉴定,该湖沉积物中烃类分布主要包括正构烷、烯烃,环状和非环状异戊二烯烃等。这些烃的来源可归属于两种即藻类和细菌,其中来源于细菌的有:植烷、2,6,10,15,19-五甲基二十烷、角鲨烷、蕨烯-7、12-新藿烯和22(29)-藿烯等。来源于藻类的有:甾烯、C_(15)、C_(17)和C_(19)正构烷烃、长链C_(29)二烯和姥鲛烷等。研究表明某些典型的烃类可能出自藻种和菌种,从而进一步说明爱丝湖的沉积环境变化。  相似文献   

10.
本文对南海深海和冲绳海槽二个柱状样进行了正构烷烃、甾烷和萜烷生物标记化合物分布特征的研究。由于它们所处的沉积环境和生源母质上的差异,反映在正构烷烃的CPI值、C_(17)和C_(18)的含量、轻重烃比值、化合物构型的转化、有机质的成熟度和17α(H)-22,29,30-三降藿烷与18α(H)-22,29,30-三降新藿烷的比值等地球化学参数上的差别。冲绳海槽沉积物的多源性决定了其有机组分的特殊性,如生物来源的C_(17)和C_(18)量占有优势,有机碳含量(1.0—1.3%)高于南海样(0.3—1.0%),重排甾烷量少,生物构型的ββ藿烷已转变成地质构型的αβ藿烷和βα型莫烷化合物。  相似文献   

11.
12.
This study examined the fate of Prudhoe Bay crude oil in nearshore sediments of the Beaufort Sea, in situ, with emphasis on the rôle of microorganisms in the weathering process. The results indicate that oil is degraded in Arctic sediments very slowly; only after 1 year's exposure was biodegradation evident. Several factors probably contributed to the slow rate of microbial weathering, including: limited populations of hydrocarbon utilising microorganisms; localised high oil concentrations; low temperatures; limiting nutrient concentrations (unfavourable C:N and C:P ratios); low oxygen tensions and limited circulation of interstitial waters in fine-grained sediments. Abiotic weathering of the oil was also slow, with limited loss of low molecular weight aliphatic and aromatic hydrocarbons during 2 years' exposure. Significant features of the overall weathering process were: lack of initial loss of low molecular weight compounds; aliphatic compounds were not preferentially degraded over aromatic compounds and C17, and lower molecular weight normal alkanes were preferentially degraded over higher molecular weight alkanes. The results of this study indicate that hydrocarbons will persist relatively unaltered for several years if Beaufort Sea sediments are contaminated with petroleum.  相似文献   

13.
Following the Amoco Cadiz crude oil spill in March 1978, marine animals in coastal and estuarine environments along the north shore of Brittany, France became heavily contaminated with crude oil. The resident benthic fauna in the oil-impacted area which survived the spill were severely stressed by the pollution. The objectives of our investigation were to document long-term trends in petroleum hydrocarbon contamination and sublethal stress in oysters and plaice from the estuaries, Aber Benoit and Aber Wrac'h. Oysters in the estuaries accumulated aliphatic and aromatic petroleum hydrocarbons to high levels and remained heavily contaminated for the duration of the 27 month investigation. Plaice, on the other hand, retained only low concentrations of petroleum hydrocarbons in muscle and liver tissue. Nevertheless, the oysters exhibited very few histopathologic and biochemical responses to the oil, whereas the plaice from the estuaries exhibited a variety of sublethal histopathologic and biochemical alterations.  相似文献   

14.
Surface sediments from the Saronikos Gulf were analyzed for their aliphatic hydrocarbon (AHC) and polycyclic aromatic hydrocarbon (PAH) content by gas chromatography – mass spectrometry (GC/MS). The concentrations of Fe, Cr, As, Sb, Co and Sc were also determined by neutron activation analysis (NAA). The survey was performed at the beginning of the operation of Athens’ sewage primary treatment unit and the results can be used to monitor the unit's long-term effects in the area. The composition of aliphatic hydrocarbons indicated a chronic oil-pollution in the Saronikos Gulf sediments. The industrially impacted Elefsis Bay sediments suffered from heavy petroleum pollution, while the sediments near the sewage outfall had a moderate degree of pollution. Mixed source patterns of polycyclic aromatic hydrocarbons with dominant pyrolytic inputs have been identified in the sediments. Total concentrations of Fe, As and Sb along with their Sc normalized values presented elevated values in Elefsis Bay sediments. Chromium was found enriched in the sediments near the Athens sewage outfall. Factor analysis results showed that a part of As and Sb in Elefsis Bay sediments could be associated with organic or sulphidic phases. In addition, the lithogenic fraction of the sediments and the Fe oxides/hydroxides were important trace element carriers. Chromium and PAH inputs from the sewage outfall were also detected. Comparison of PAH and trace element concentrations with internationally-used sediment quality guidelines (SQG) revealed that Elefsis Bay sediments had the greatest potential of causing adverse effects in benthic organisms.  相似文献   

15.
本文通过对我国近海油气资源的分布特征进行分析 ,指出渤海湾盆地是我国近海石油的主力产区。天然气的主力产区为莺歌海盆地和东海陆架盆地 ,目前勘探的重点应放在渤海湾盆地 ,其次是东海陆架盆地 ,珠江口盆地第三。在加强对新生代盆地勘探的同时 ,应重视对中生代地层的勘探 ;在深化浅水区勘探的同时 ,不失时机地开展深水勘探 ;在加强构造圈闭勘探的同时 ,密切注视非构造圈闭的油气资源的勘探  相似文献   

16.
潮间带作为海陆交界处,易受到来自海洋的石油污染,且各类石油烃进入沉积物后的降解过程尚不清楚。前人在各类生境中对好氧微生物烃降解方面已有较多研究,但对近海潮间带环境中的厌氧烃降解鲜有报道。本研究对青岛女岛湾潮间带沉积物深层样品以混合烃(中长链烷烃、多环芳烃)为碳源,硫酸盐作为电子受体进行厌氧富集培养。富集菌群的细菌多样性表明在混合烃作为碳源的作用下,优势菌群转变为脱硫叠球菌科(Desulfosarcinaceae)、脱硫杆菌科(Desulfobacteraceae)等具有石油烃降解潜力的硫酸盐还原菌。经分离纯化得到一株厌氧烃降解菌ND17,与地下脱硫弧菌属模式种Desulfovibrio subterraneus HN2T 16S rRNA基因序列的相似度为99.93%。进一步实验表明,菌株ND17在厌氧条件下对二十四烷和菲的降解率可分别达到53.9%和35.7%。这也是首次对脱硫弧菌属单菌在厌氧条件下进行石油烃降解的研究。脱硫弧菌作为一种广泛分布在厌氧环境的细菌,本研究为进一步认识其在海洋石油污染环境中的修复潜力提供了支撑。  相似文献   

17.
Surface sediment samples from a matrix of fifty-five sites covering virtually the entire Bohai Sea (Bohai), China were analyzed for total organic carbon (TOC), total nitrogen (TN), n-alkanes, unresolved complex mixture (UCM), biomarkers and stable carbon isotopic composition (δ13C), and principal component analysis was performed for source identification of organic matter (OM). The distribution of organic carbon correlated well with sediment grain size with the finest sediments having the highest concentration, suggesting the influence of hydrodynamics on the accumulation of sedimentary organic matter (SOM). The corrected TOC/ON (organic nitrogen) ratios and δ13C indicated mixed marine and terrestrial sources of SOM. Results suggested that δ13C could be used as a potential indicator to observe the dispersion of Huanghe-derived sediments in Bohai. Total n-alkane concentrations varied over 10-fold from 0.39 to 4.94 μg g− 1 (dry weight) with the maximum terrigenous/aquatic alkane ratio observed at the Huanghe River Estuary (HRE) due to more higher plant OM from riverine inputs. C12–C22 n-alkanes with even-to-odd predominance were observed in several central-eastern Bohai sites. The HRE and its adjacent area is the main sink for the Huanghe river-derived OC. The ubiquitous presence of UCM, biomarkers (hopanes and steranes) and PCA results indicated the presence of petroleum contamination in Bohai, mainly from offshore oil exploration, discharge of pollutants from rivers, shipping activities and atmospheric deposition.  相似文献   

18.
为保障渤海海域的污染物控制和生态环境保护,文章基于已有监测数据,分析渤海海域表层沉积物中多环芳烃(PAHs、LPAHs、HPAHs和CPAHs)的分布、来源及其与沿岸陆地的相关性。研究结果表明:PAHs、LPAHs、HPAHs和CPAHs含量最高的海湾分别为莱州湾、渤海湾、辽东湾和渤海湾,3个海湾均以LPAHs为主;PAHs及其各类组成的来源主要包括入海河流携带的陆源污染物,海流输送并沉积的泄漏原油以及港口、城市和工业基地的排放污水;PAHs的分布受沿岸土地开发利用以及工业和城镇建设等人类活动影响较大,且沿岸土壤中的PAHs对海洋环境造成破坏。  相似文献   

19.
我国近海海洋油气产量接替现状与面临的问题及应对策略   总被引:1,自引:0,他引:1  
我国海洋油气勘探开发经过近年来的发展,逐渐成为重要的储量与产量接替区.主要表现在:渤海盆地逐渐接替南海东部成为我国近海目前勘探前景最好、也是对我国油气储量和产量接替贡献最大的海区;南海西部通过重点地区、重要目的层和新区新领域的勘探突破,油气稳产前景良好;我国海上天然气剩余技术可采储量非常可观,产量增长比例上升迅速,成为...  相似文献   

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