大地构造研究在我国东部油气勘查中的应用

中国含油气区大地构造研究,从槽台观点到板块构造基础理论,应用到东部地区着重研究了陆缘地壳和上地幔岩石圈层结构、运动和发展规律。阐明自印支期以来新全球构造阶段地壳深部活动机制,有效地解释了中新生代裂谷,裂陷盆地的起源和演化,以及构造对油气的生成、运移、聚集、保存直至成藏的控制作用,为油气勘查从陆地到海域发现大批油气田做出了积极贡献。     

棱梭对饵料摄食与吸收利用研究

本文采用~(14)C标记技术测定棱梭幼体对褶皱臂尾轮虫、卤虫和亚心形扁藻等饵料的摄衾率、吸收率扣利用率,并以~3H-葡萄糖和~(14)-苯丙氨酸作示踪剂研究人工配合饵料中葡萄糖和氨基酸在棱梭体内转运和分布情况。结果表明,卤虫、褶皱臂尾轮虫都是棱梭幼体合适的饵料;氨基酸更多地参与了棱梭组织中的细胞代谢,而葡萄糖则是棱梭体内重要的能源物质。     

非均匀对流边界层的地转强迫流动和动量输送

用大涡模拟方法研究地转强迫下的对流边界层流动和地表热力非均匀性影响.模拟重现了典型对流边界层的平均风廓线和动量通量垂直分布.地表热力非均匀性对区域平均风速和动量通量分布无明显影响,但边界层内的局地流动性状和湍流动量输送情况有系统性的改变.下风较热区近地面风速增强而高空流动受到阻塞,上风较冷区之上情况则正好相反.对应于平均流动场的畸变,地表较热区之上边界层大部可以出现动量向上输送的情况,较冷区成为大气动量下传的主要通道.地面应力在较热区增强、较冷区减弱的趋势明显.     

海相优质页岩的形成环境及发育模式——以中扬子地区秭归新滩剖面五峰—龙马溪组页岩为例

运用地球化学和岩石学方法,从古盐度、古气候、古生产力、海域封闭性以及氧化还原条件等方面,分析中扬子地区秭归新滩剖面上奥陶统五峰组—下志留统龙马溪组海相优质页岩的形成环境,并探讨了优质页岩发育的控制因素及模式。结果表明:中扬子地区五峰—龙马溪组优质页岩以硅质页岩为主,主要发育在五峰组至埃隆阶底部;优质页岩主要形成于温暖潮湿、低盐度—正常盐度、弱封闭—半封闭的缺氧环境中,并且具有较高的古生产力;海相优质页岩的发育是构造活动、海平面升降以及陆源—生物硅质供应等多因素综合作用的结果,而在埃隆期之后,随着扬子板块的持续向西北推进,海域面积不断萎缩,生物硅质供应降低,陆源碎屑供应迅速增加,优质页岩不再发育。最后,总结了海相优质页岩的发育模式。     

海相页岩气目标区优选研究——以湖南某中标区块为例

通过野外调查获得研究区块详实的地质资料,龙马溪组富有机质页岩形成于封闭的深水滞留盆地,真厚度在22.26~28.63 m,具有自东向西增高的趋势,富含笔石化石;TOC含量在1.16%~4.31%,平均为2.06%;干酪根以Ⅰ型为主,镜质体反射率在1.87%~3.15%,基本处于过成熟早期阶段;页岩储层属于低孔低渗类型,但页岩富含硅质,脆性矿物含量在41.13%~84.95%,平均66.76%,有利于储层的后期压裂改造;页岩储层吸附能力较好,饱和吸附量为1.24~3.10 m3/t,平均2.11 m3/t,与TOC含量具有高度的线性关系。区块内龙马溪组埋深适中,有效勘探面积达540 km2,参数井显示页岩含气量较高,综合分析区内含气页岩埋藏深度、构造条件以及地表条件等因素,优选出龙家寨向斜和青安坪向斜的核部为页岩气勘探目标区。     

中国东北地区地壳、上地幔速度结构及其对矿产能源形成的控制作用

中国东北地区处于古亚洲洋和滨太平洋构造域叠合部位, 地质构造极其复杂. 利用东北及华北地区部分台网所接收的近震及远震走时资料获得东北地区地壳与上地幔三维P波速度结构, 成像分辨率在80 km左右. 成像结果表明东北地区地壳与上地幔具有较强的横向不均匀性. P波速度异常走向大体呈北东向, 与该区地表构造走向一致. 5 km深度的速度异常与地表起伏形态有很好的对应关系: 阴山、燕山与大兴安岭造山带表现为高速异常; 渤海湾盆地, 松辽盆地表现为低速异常, 渤海湾低速异常一直延伸至 >200 km深度. 东北地区呈现两个明显的低速异常条带, 分别是沿着长白山一线与松辽盆地地区, 其中长白山低速异常延伸至400 km深度附近. 地幔转换带 (410~660 km)表现为显著高速异常体, 这与西向俯冲的高速太平洋板块在地幔转换带中的滞留相对应. 较高分辨率的三维速度成像结果表明东北地区构造演化 (如岩浆活动、岩石圈演化、深震与火山活动等) 与东北亚地区大地幔楔内软流圈上涌与西太平洋板块在地幔转换带中的滞留密切相关. 东北地区的岩浆活动在矿产与油气资源的形成过程中起着提供物源和深层控制作用.     

福建九龙江口入海泥沙的扩散和河口湾的现代沉积

本文阐述了40年来九龙江入海泥沙量增加了两倍,入海泥沙在海门岛—鸡屿一带的浅滩区,其年平均淤积8—10cm,一次洪水流域搬来悬浮泥沙,使河口湾新淤积层厚2—3cm.并指出、进入河口湾的三条汉河各有独立的扇形粗粒冲积浅滩;悬移质的粉砂、粘土粒扩散至鼓浪屿以南海域;构成三角洲沉积主体的河口浅滩区的沉积速度由入海泥沙倍增而相应地加快进行.     

基于微机电加速度计的地震烈度计

为了实现破坏性地震强度的速报,提高地震应急响应效率,指导抗震救灾,设计一种新型地震烈度计。采用性价比较高的微机电加速度计MODEL-1221作为地震传感器,利用4个通道的同步24位模数转换器ADS1274进行地震信号转换,使用32位嵌入式处理器AT91RM9200作为地震事件的判定和烈度参数计算的平台,保证仪器整体性能,能够满足地震烈度速报需要;此外,该地震烈度计具有开关量输出,可以作为地震紧急处置系统的地震开关来使用,实现一机多用,一机多能。     

Asynchrony of spring phytoplankton response to temperature driver within a spatial heterogeneity bay of Three-Gorges Reservoir, China

The increased air temperature is expected to have important driver on spring phytoplankton dynamics. To test whether spatial heterogeneity modifies the synchronous responses of phytoplankton to regional temperature driver, we evaluate temporal coherences for physical factors (temperature, water stability and non-algal light extinction), nutrients (nitrogen, phosphorus and silicon), and biomass and density of phytoplankton by Pearson correlation analysis and synchrony for phytoplankton community dynamics by Mantel test and nonmetric multi-dimensional scaling (NMS), during spring bloom (February 23–April 28, 2005) within Xiangxi Bay, a high spatial gradient bay of Three-Gorges Reservoir (China). The high level of temporal coherences for surface water temperature (r = 0.946, p < 0.01) and relative water column stability (r = 0.750, p < 0.01) were found between pair sites (A and B), in which the increase trends occurred with increase in regional air temperature during the study period. However, the low synchrony for phytoplankton dynamics were indeed observed between Site A and B, especially for the density of common dominant taxa (Cyclotella spp.: r = 0.155, p = 0.388) and community structure (Mantel test: r = 0.351). Moreover, the local habitat characteristics such as nutrient (nitrogen and phosphorus) and non-algal light extinction showed low levels of temporal coherence. It indicated that local community of phytoplankton varies rather independently within the single lentic bay with high spatial heterogeneity and that dispersal of algal organisms among locations cannot overwhelm out these local dynamics. Contrary to many studies, the present results argued that, in a small geographic area (i.e., a single reservoir bay of approximately 24 km length), spatial gradients also may influence spring phytoplankton response to regional temperature driver.     

Carbon,nitrogen and phosphorus coupling relationships and their influencing factors in the critical zone of Dongting Lake wetlands,China

Wetland is a transition zone between terrestrial and aquatic ecosystems, and is the source and sink of various biogenic elements in the earth’s epipelagic zone. In order to investigate the driving force and coupling mechanism of carbon (C), nitrogen (N) and phosphorus (P) migration in the critical zone of lake wetland, this paper studies the natural wetland of Dongting Lake area, through measuring and analysing the C, N and P contents in the wetland soil and groundwater. Methods of Pearson correlation, non-linear regression and machine learning were employed to analyse the influencing factors, and to explore the coupling patterns of the C, N and P in both soils and groundwater, with data derived from soil and water samples collected from the wetland critical zone. The results show that the mean values of organic carbon (TOC), total nitrogen (TN) and total phosphorus (TP) in groundwater are 1.59 mg/L, 4.19 mg/L and 0.5 mg/L, respectively, while the mean values of C, N and P in the soils are 18.05 g/kg, 0.86 g/kg and 0.52 g/kg. The results also show that the TOC, TN and TP in the groundwater are driven by a variety of environmental factors. However, the concentrations of C, N and P in the soils are mainly related to vegetation abundance and species which influence each other. In addition, the fitted curves of wetland soil C-N and C-P appear to follow the power function and S-shaped curve, respectively. In order to establish a multivariate regression model, the soil N and P contents were used as the input parameters and the soil C content used as the output one. By comparing the prediction effects of machine learning and nonlinear regression modelling, the results show that coupled relationship equation for the C, N and P contents is highly reliable. Future modelling of the coupled soil and groundwater elemental cycles needs to consider the complexity of hydrogeological conditions and to explore the quantitative relationships among the influencing factors and chemical constituents.