南极普里兹湾沉积物中生物硅对粒度测量结果的影响

为了探讨生物硅对沉积物粒度测量结果的影响, 本文采用两种不同前处理方法对普里兹湾重力柱状样品进行了粒度测试。结果表明, 生物硅对沉积物的平均粒径以及黏土、粉砂、砂组分的影响较小, 而对沉积物的分选、偏态、峰态以及粒度频率分布的影响较显著。结合两组粒度组分相关性分析以及各粒级含量累积减小值, 认为生物硅对沉积物中砂、粉砂、黏土级组分含量的影响逐渐减小, 这也造成未去除生物硅的沉积物粒度测量结果偏粗。另外, 通过对比发现普里兹湾沉积物中生物硅粒径主要分布在<3Φ、5.25Φ—7.25Φ、8.75Φ—9.75Φ的粒径范围。极地研究中, 沉积物粒度结果为重建古环境变化提供重要参考, 本文研究认为在普里兹湾海域沉积物粒度研究中去除生物硅对研究结果有积极作用。     

Sedimentary Characteristics of the Second Marine Layer During the Late Marine Isotope Stage 3 in Southern Yellow Sea and Their Response to the East Asian Monsoon

We use the particle size of sediments in core YS01 A to study the sedimentary environment of the mud deposit in the central South Yellow Sea of China during late Marine Isotope Stages 3(MIS3;40.5 kyr–31.3 kyr).In addition,the East Asian Monsoon and its relationship with the North Atlantic Ocean climate change are discussed based on the sensitive grain-size calculation and the spectrum analysis.The results show that during late MIS3,the muddy area in the central South Yellow Sea experienced the evolution of coastal facies,shallow marine facies,coastal facies,and continental facies,with weak hydrodynamic conditions.Compared with other climate indicators,we found that there were many century to millennium-scale climate signals documented in the muddy area sediments in the central South Yellow Sea.According to our particle size results,three strong winter monsoon events occurred at 37.6 kyr,35.6 kyr and 32.2 kyr.The East Asian Winter Monsoon records in core YS01 A are consistent with the Greenland ice core and the Hulu cave stalagmite δ~(18)O.The millennial and centennial scale cycles,which are 55 yr,72 yr,115 yr,262 yr respectively,correspond to solar activity cycles,while the 1049 yr and 2941 yr cycles correspond to the Dansgaard-Oeschger cycles.These cycles indicate that the paleoclimate evolution of the area was controlled by the solar activities,with the high-latitude driving thermohaline circulation as the main energy conveyor belt,followed by the sea-air-land amplification of the winter monsoon variation in the central Yellow Sea in the late MIS3.     

南海万安盆地的构造样式与构造圈闭

通过对大量多道地震剖面的解释和分析,认为南海万安盆地发育有潜山披覆、基底张性断块、挤压背斜和骨牌式构造等４类典型构造样式,并形成背斜型和断块型两类主要的构造圈闭,构成了盆地内重要的油气圈闭类型。     

南海北部潮汕坳陷侏罗系古地貌特征及沉积相模式

南海北部潮汕坳陷中生界极具油气勘探潜力;综合运用最新采集的地震资料结合测井数据,在侏罗纪地层精细划分的基础上,通过对目的层剥蚀量计算,对侏罗系古地貌进行了恢复;利用残留地层的沉积相标志分析结果,建立了潮汕坳陷侏罗系沉积模式。结果表明,在早侏罗世末期和中侏罗世末期,地层遭受剥蚀改造;古地貌各要素对沉积体系发育的影响,古隆起（凸起）指明了沉积物的来源和方向;古海底峡谷是沉积物从物源区搬运到沉积区的重要运移通道;斜坡带为重要的沉积场所,并对储层的品质和规模有巨大影响,制约着盆地可容纳空间的大小;盆底的地貌形态控制着沉积体形态和产状。研究结果表明,古地貌恢复后的各要素在时空上的有效配置关系是准确把握沉积体系展布特征及范围的关键因素,对沉积储层及烃源岩的控制作用非常明显。该结论对侏罗系下一步勘探及有利储层预测有积极意义。     

基于ARM的光纤Bragg光栅地震观测系统的研究

为满足地震观测系统对实时性、高精度以及网络化的要求,提出了基于光纤Bragg光栅传感器和ARM的嵌入式系统设计方案,阐述了可调光纤F-P滤波器的工作机理和特点,并介绍了基于FBG传感器和ARM的地震观测系统的硬件结构和软件设计.采用三星公司的S3C2440对经过可调谐F-P腔解调后的波长信息进行采集,并对得到的数据进行处理.实验结果表明,该系统在处理精度和实时性方面都能达到要求,性价比高,有一定实用价值.     

胜利埕岛油田海洋工程环境地理信息系统

１系统介绍胜利埕岛油田位于渤海湾南部现代黄河三角洲北部浅海区,１９６４～１９７６年黄河在该区入海。在Ｍａｐｉｎｆｏ平台上开发的胜利埕岛油田海洋工程环境地理信息系统（简称埕岛ＧＩＳ）集成了埕岛地区１９６４年以来以海岸带变迁及海底冲淤变化为主的海洋工程环...     

黄河三角洲钓口叶瓣河道与岸线演化分析

现代黄河三角洲是由多个叶瓣组成,钓口流路叶瓣是1964—1976年形成,1976年之后废弃,这段时期历史记录相对比较完整。利用Landsat-TM卫星遥感图像,对黄河三角洲钓口叶瓣1964—2011年之间的岸线以及河道进行识别,结合历史测量资料,对钓口叶瓣岸线、河道变化规律进行了系统的分析。研究结果表明,1964年以来,岸线变化可划分为填湾取直—快速淤进—快速蚀退—缓慢蚀退4个演化阶段;河道变化可划分为漫流充填—河口突出—单一顺直—决口分叉—废弃5个阶段。     

Disparity between measured and BSR heat flow in the Xisha Trough of the South China Sea and its implications for the methane hydrate

We calculate the heat flow from the depth of bottom-simulating seismic reflectors (BSRs) on a seismic profile in the Xisha Trough of the South China Sea, and compare them with the probe heat flow measurements. The BSR heat flow turn out to be 32–80 mW/m², significantly lower than the measurements of 83–112 mW/m². Such big disparity cannot be ascribed only to the errors from parameters (parameter errors) that traditionally believed to influence the BSR heat flow. Besides the parameter errors, we discuss emphatically the errors coming from the theoretical assumption for the BSR heat flow determination (theoretical errors), which occur when the BSR depth does not coincide with the base of the methane hydrate stability zone (MHSZ). If BSR stays bellow the base of MHSZ, lying at the top of free gas zone, the derived heat flow would be underestimated. Compared with the parameter errors, the theoretical errors would be relatively larger in some geological settings. The disparity between measured and BSR heat flow in the Xisha Trough might be mainly due to the theoretical error. Based on the theoretical model, assuming that the BSR lying at the top of the free gas zone, the methane flux along the Xisha seismic profile is estimated, and the thickness of the methane hydrate occurrence zone is predicted.     

南海北部陆坡西沙海槽XS-01站位沉积物孔隙水的 地球化学特征及其对天然气水合物的指示意义*

天然气水合物是近年来国际上发现的一种新型能源,大量赋存在海底沉积物中。西沙海槽位于南海北部陆坡区,周边有多个大型深水油气田区。对该区地形地貌、地质构造和沉积条件分析以及地球物理BSR分布表明,西沙海槽是我国海洋天然气水合物资源勘查的一个有利远景区。文章主要研究了位于西沙海槽最大BSR区内的XS-01站位沉积物孔隙水的地球化学特征,发现该站位孔隙水阴阳离子浓度和微量元素组成特征变化显示出可能与天然气水合物有关的明显地球化学异常,与国际上己发现有天然气水合物地区的异常相类似。因此,认为该站位是西沙海槽区最有利的天然气水合物赋存区,值得进一步的勘查工作。