Cambrian wave‐dominated tidal‐flat deposits,central Wisconsin,USA

In central Wisconsin, Cambrian strata of the Elk Mound Group record deposition on open‐coast, wave‐dominated tidal flats. Mature, medium‐grained quartz arenite is dominated by parallel‐bedding with upper‐flow regime parallel‐lamination, deposited during high‐energy storms that also produced three‐dimensional bedforms on the flats. Abundant wave ripples were produced as storms waned or during fair weather, in water depths ≤2 m. Indicators of variably shallow water (washout structures and stranded cnidarian medusae) and subaerial exposure (adhesion marks, rain‐drop impressions and desiccation cracks, including cracked medusae) are abundant. Parallel‐bedded facies preserve a Cruziana ichnofacies, similar to other Cambrian tidal‐flat deposits. Flats were dissected by small, mainly straight channels, the floors of which were grazed intensely by molluscs. Most channels were ephemeral but some developed low levées, point bars and cut‐banks, probably reflecting stabilization by abundant microbial mats and biofilms. Channels were filled with trough cross‐bedding that is interpreted to have been produced mainly during storm runoff. The strata resemble deposits of open‐coast, wave‐dominated tidal flats on the east coast of India and west coast of Korea. Ancient wave‐dominated and open‐coast tidal flats documented to date appear to have been limited to mud‐rich strata with ‘classic’ tidal indicators such as flaser bedding and tidal bundles. The Cambrian (Miaolingian to early Furongian) Elk Mound Group demonstrates that sandy, wave‐dominated tidal flats also can be recognized in the stratigraphic record.     

鄂尔多斯盆地吴起地区延长组长4+5段储层非均质性特征

储层非均质性对剩余油分布和水驱或气驱波及系数影响较大,开展储层非均质精细评价,是油田开发方案调整和剩余油挖潜必不可少的内容。利用密井网测井资料和岩矿鉴定等资料,从沉积、成岩作用等方面对吴起油沟油田长4+5段储层非均质进行了研究。结果表明,研究区长4+5段诸层为三角洲前缘沉积末端,单期水下分流河道规模较小且改道频繁,层内泥质夹层不发育,层间隔层发育,单砂体连通性差,非均质性较强;纵向上将长4+5段分为长4+5_1、长4+5_2~1、长4+5_2~2三个小层,受沉积环境和成岩作用,特别是碳酸盐胶结作用的影响,层内非均质性多为正韵律或复合韵律,其中长4+5_1储层非均质性最强,长4+5_2~2储层非均质性最弱;从层间非均质性来看,其中长4+5_1单层砂体薄,分层系数最大,长4+5_2~2储单层砂体厚度大,分层系数较小;从平面非均质性来看,长4+5_1砂体呈交切窄条带状发育,砂体厚度横向变化大,平面非均质性较强;长4+5_2~1砂体呈孤立条带状分布,砂体欠发育,以分流涧湾为主;长4+5_2~2砂体厚度大,且呈连片发育,平面非均质性较弱。     

超声强化零价铁活化过硫酸盐降解地下水中二恶烷

本文采用超声强化零价铁活化过硫酸盐氧化降解地下水中的二恶烷污染物。主要探讨了零价铁添加量、超声强化、不同过硫酸盐用量及地下水中不同碳酸根浓度等对二恶烷降解效果的影响,并对零价铁进行了表征分析。结果表明：超声能够促进硫酸根自由基和Fe²⁺的产生,提高二恶烷的降解率;零价铁添加量和过硫酸盐浓度的增加均能促进二恶烷的降解,但零价铁相对过硫酸盐过多时将降低最终降解率;地下水中的碳酸根会消耗硫酸根自由基,因此碳酸根浓度越高,二恶烷降解率越低。超声强化零价铁活化过硫酸盐氧化法能够有效降解二恶烷,并具有应用于处理地下水中二恶烷的潜力。     

缩骨鲫(Carassius auratus sogu var.)MC4R克隆、组织分布以及与生长相关SNPs的筛选

黑色素皮质素受体-4(Melanocortin reporter-4,MC4R)是G蛋白偶联受体超家族成员,在能量调控中发挥重要作用。本实验采用同源克隆以及染色体步移对缩骨鲫(Carassius auratus sogu var.)MC4R基因进行克隆,对其核苷酸序列和推测的氨基酸序列进行生物信息学分析,通过Real-time PCR对其m RNA组织分布进行研究,并对缩骨鲫MC4R编码区潜在的与生长相关的SNPs进行筛选。本实验克隆MC4R基因组基因长度为2854bp,只包含一个外显子,长度为981bp,共编码326个氨基酸,MC4R共有七个跨膜结构,是较为稳定的疏水蛋白。缩骨鲫MC4R与鲫鱼的MC4R氨基酸序列的同源度最高达到99.3%,与MC3R和MC5R同源度相对其他MCRs成员较高。缩骨鲫MC4R m RNA在脑中表达量最为显著,眼中次之,肌肉,卵巢和肾脏中表达较少,在鳃、肠、心脏和肝胰腺中微量表达。在MC4R的CDs区内检测到6个与生长潜在相关的SNPs:两个错义突变(A199G和A881C),4个同义突变(A123G,C231T,A444G和C480T)。本实验可为缩骨鲫生长和发育的分子机制研究以及遗传育种提供基础资料。     

Large capacity multi-float configurations for the wave energy converter M4 using a time-domain linear diffraction model

The moored three-float line absorber WEC M4 has been developed to optimise power capture through experiments and linear diffraction modelling. With the progression down wave from small to medium to large floats, the device heads naturally into the wave direction. The bow and mid floats are rigidly connected by a beam and a beam from the stern float is connected to the hinge point above the mid float for power take off (PTO). Increasing the bow to mid float spacing to be more than 50% greater than the mid to stern float spacing has been found to improve power capture. To increase power capture further and potentially reduce electricity generation cost the number of mid floats and stern floats is increased while maintaining a single bow float for mooring connection. The bow and mid floats still form a rigid body while the stern floats may respond independently. A time domain linear diffraction model based on Cummins method has been applied to configurations of 121, 123, 132, 133, and 134 floats where the numbers indicate the number of floats: bow, mid, stern. This shows how power capture is increased while response remains similar. We only consider uni-directional (long-crested) waves with narrow band width typical of swell. By considering scatter diagrams for various offshore sites capacities may range from 3.7 MW to 17.3 MW for the eight float system with a capacity factor of 1/3 while the cost of electricity assuming capital cost to be a fixed multiple of steel cost is reduced from that for the three-float system.     

物探方法在强风化区填图中的应用探索

华南强风化区覆盖较厚,露头少,植被发育,通行困难,利用传统的地质填图方法很难有效查明风化覆盖层及其下伏地层、岩石、构造、矿产等地质特征。笔者利用浅层地震、高密度电法、EH4电磁成像等综合物探方法,对风化层厚度、基岩的岩性和产状、隐伏断裂等进行探测试验。通过对3种方法所得数据的分析和野外验证结果,了解了3种物探方法的有效性和适用性,初步总结了在强风化区填图运用多种物探手段填图的方法。     

基于孔喉结构建立致密砂岩储层评价方案——以松南中央坳陷泉四段为例

致密砂岩储层评价方案是识别储层"甜点"的基础,也是致密油勘探的重点和难点,但目前国内对此尚无统一认识。为此,以松南中央坳陷区泉四段致密砂岩为例,综合常规压汞、恒速压汞、高压压汞等多种资料对致密储层微观孔喉结构进行了精细表征,并以此为基础建立了致密砂岩储层评价方案。结果表明:研究区致密砂岩孔喉小、物性差,储集空间以次生溶孔为主;储层渗透性主要由占小部分体积的最大孔喉半径所控制,喉道半径越大、大喉道所占比例越高,致密储层的渗透率(K)就越高、品质就越好。在此基础上,由孔喉结构的差异性出发,将松南中央坳陷区泉四段致密砂岩储层分类4类,其中,石油能够充注至Ⅰ—Ⅲ类致密储层,且Ⅰ类致密储层(K为(0.1~1.0)×10~(-3)μm~2)品质最高,可视为储层"甜点"。     

钻孔四分量应变观测自检内精度分析

根据钻孔四分量应变观测特点,分析了评价该观测手段的质量指标:相对标定自检内精度.介绍了相对标定自检内精度方法以及存在的问题.通过对比分析平均值、相关系数等,提出不同的求偏差方法,改进了相对标定自检内精度法,使其能尽量客观地评价观测质量.     

松辽盆地龙西地区泉四段砂岩成岩序列及孔隙演化特征

通过岩芯观察、镜下薄片、扫描电镜和X衍射分析等资料,对松辽盆地龙西地区泉四段砂岩的岩石学特征、成岩作用类型、成岩阶段划分和成岩共生序列及孔隙演化特征进行了研究。结果表明:龙西地区泉四段主要为长石质岩屑砂岩,局部为岩屑质长石砂岩;经历的主要成岩作用类型有压实作用、自生石英胶结作用、自生黏土矿物胶结作用、碳酸盐胶结作用、交代和溶蚀作用等;龙西地区泉四段砂岩为中成岩阶段A期,且细分为A1和A2亚期;随着成岩演化,压实和胶结作用使得原生孔隙减小,而溶蚀作用使得储层孔隙结构得到改善;孔隙类型由缩小粒间孔组成变为由缩小粒间孔和溶蚀粒间孔组合组成。     

25 ℃时NaClNH4ClH2O三元水盐体系相平衡的研究

利用湿渣法,研究了25℃时NaCl-NH4Cl-H2O三元水盐体系的固液相平衡关系,测出了NaCl和NH4Cl在水中的溶解度数据,并绘制了相图。结果表明该体系在25℃时的相图存在6个区域,即:纯NH4Cl结晶区;纯NaCl结晶区;以NH4Cl为主的固溶体结晶区;以NaCl为主的固溶体结晶区;以NH4Cl为主的固溶体和以NaCl为主的固溶体共同结晶区以及不饱和溶液区。