共查询到20条相似文献，搜索用时 33 毫秒
1.
Numerical simulation for accuracy of velocity analysis in small-scale high-resolution marine multichannel seismic technology 总被引：1，自引：0，他引：1
When used with large energy sparkers, marine multichannel small-scale high-resolution seismic detection technology has a high resolution, high-detection precision, a wide applicable range, and is very flexible. Positive results have been achieved in submarine geological research, particularly in the investigation of marine gas hydrates. However, the amount of traveltime difference information is reduced for the velocity analysis under conditions of a shorter spread length, thus leading to poorer focusing of the velocity spectrum energy group and a lower accuracy of the velocity analysis. It is thus currently debatable whether the velocity analysis accuracy of short-arrangement multichannel seismic detection technology is able to meet the requirements of practical application in natural gas hydrate exploration. Therefore, in this study the bottom boundary of gas hydrates (Bottom Simulating Reflector, BSR) is used to conduct numerical simulation to discuss the accuracy of the velocity analysis related to such technology. Results show that a higher dominant frequency and smaller sampling interval are not only able to improve the seismic resolution, but they also compensate for the defects of the short-arrangement, thereby improving the accuracy of the velocity analysis. In conclusion, the accuracy of the velocity analysis in this small-scale, high-resolution, multi-channel seismic detection technology meets the requirements of natural gas hydrate exploration. 相似文献
2.
Natural gas hydrates are considered as strategic resources with commercial potential in the 21st century. Obvious BSR characteristics
will be shown on seismic profiles, if there exist natural gas hydrates. The AVO method is one of the methods which can be
used to identify and forecast lithologic characteristics and fluid properties by using the relationship between Amplitude
and Offset. AVO anomaly is one of the significant signs to check out whether or not there is free gas below the BSR, so it
can be used to detect natural gas hydrates from the seismic profile. Considering the geological and geophysical characteristics
of the Okinawa Trough and making use of the techniques mentioned above, we can conclude that the conditions there are favorable
for the formation and concentration of natural gas hydrates. By analyzing the data collected from the study area, one can
discover many different anomalous phenomena on the seismic profile which are related to the existence of natural gas hydrates.
Preliminary estimation of the natural gas hydrates in the Okinawa Trough shows that the trough is rich in natural gas hydrates
and may become a potential important resources exploration area. 相似文献
3.
The large deep-sea area from the southwestern Qiongdongnan Basin to the eastern Dongsha Islands,within the continental margin of northern South China Sea,is a frontier of natural gas hydrate exploration in China.Multiform of deep-sea sedimentations have been occurred since late Miocene,and sediment waves as a potential quality reservoir of natural gas hydrate is an most important style of them.Based on abundant available data of seismic,gravity sampling and drilling core,we analyzed the characteristics of seismic reflection and sedimentation of sediment waves and the occurrence of natural gas hydrate hosted in it,and discussed the control factors on natural gas hydrate accumulation.The former findings revealed the deep sea of the northern South China Sea have superior geological conditions on natural gas hydrate accumulation.Therefore,it will be of great significance in deep-sea natural gas hydrate exploration with the study on the relationship between deep-sea sedimentation and natural gas hydrate accumulation. 相似文献
4.
Olumuyiwa T. Akinsanpe Adekunle A. Adepelumi Uzochukwu K. Benjamin Dele E. Falebita 《中国海洋大学学报(英文版)》2017,16(6):1027-1034
Comprehensive qualitative and semi-quantitative seismic analysis was carried out on 3-dimensional seismic data acquired in the deepwater compressional and shale diapiric zone of the Niger Delta Basin using an advanced seismic imaging tool. The main aim of this work is to obtain an understanding of the forming mechanism of the gas hydrate system, and the fluid migration paths associated with this part of the basin. The results showed the presence of pockmarks on the seafloor and bottom simulating reflectors (BSRs) in the field, indicating the active fluid flux and existence of gas hydrate system in the area. In the area of approximately 195 km2 occupying nearly 24% of the entire study field, three major zones with continuous or discontinuous BSRs of 3 to 7 km in length which are in the northeastern, southern and eastern part of the field respectively were delineated. The BSR is interpreted to be the transition between the free gas zone and the gas hydrate zone. The geologic structures including faults (strike-slip and normal faults), chimneys and diapirs were deduced to be the main conduits for gas migration. It is concluded that the biogenic gases generated in the basin were possibly transported via faults and chimneys by advection processes and subsequently accumulated under low temperature and high pressure conditions in the free gas zone below the BSR forming gas hydrate. A plausible explanation for the presence of the ubiquitous pockmarks of different diameters and sizes in the area is the transportation of the excessive gas to the seafloor through these mapped geologic structures. 相似文献
5.
Jin Jiapeng Wang Xiujuan He Min Li Jie Yan Chengzhi Li Yuanping Zhou Jilin Qian Jin 《中国海洋湖沼学报》2020,38(4):1188-1200
New acquired and reprocessed three-dimensional(3 D) seismic data were used to delineate the distribution and characterization of bottom simulating reflections(B SRs) in the Chaoshan Sag,in the eastern part of Dongsha Island,South China Sea.Three submarine canyons with different scales were interpreted from the 3 D seismic data,displaying three stages of canyon development and are related with the variation of BSR.Abundant faults were identified from the coherence and ant-tracing attributions extracted from3 D seismic data,which provide the evidence for fluid migration from deeper sediments to the gas hydrate stability zone(GHSZ).The uplift of Dongsha Island created a large number of faults and leads to the increased seafloor erosion.The erosion caused the cooling of the seafloor sediments and deepening of the base of the gas hydrate stability zone,which is attributed to the presence of paleo-BSR and BSR downward shift in the study area.Hence,methane gas may be released during the BSR resetting and gas hydrate dissociation related with seafloor ero sion. 相似文献
6.
天然气水合物储层地震波振幅属性研究 总被引：1，自引：0，他引：1
以实际水合物存在的美国布莱克海台地震数据为例,利用地震剖面中4个层位(海底层、水合物顶层、水合物层和游离气层)地震数据进行了地震属性的提取及属性分析,研究了各层位的属性特征。结果表明:均方根振幅、平均绝对振幅、平均能量变化、振幅峰态、绝对振幅积分、总能量、功率谱最大值、有限带宽能量等8种属性值在各层位的分布情况基本相同,即海底最高,其余依次是水合物层、游离气层和水合物顶层,可区分出水合物层和游离气层。由此,通过对比各层位的振幅属性值,可以指示天然气水合物的存在,为水合物识别及其开采提供参考依据。 相似文献
7.
蜀南地区茅口组古岩溶识别标志及储层预测 总被引：1，自引：0，他引：1
为预测蜀南地区茅口组储层,通过地质、钻井与岩心观察,地震及测井、地化指标分析等方法确定古岩溶发育状况,结合生产测试资料分析古岩溶储层在地震和测井上的响应特征.结果表明:该区主要储集空间类型为裂缝—溶洞型;储层地震响应总体表现为地震波的异常反射、相干剖面的不连续性及速度反演出现低速区;测井响应表现为深、浅侧向电阻率降低且出现正差异,密度减小,中子孔隙度和声波时差增大,而井径和自然伽马曲线的变化受空隙充填控制.该结果对该区储层预测及油气勘探具有指导意义. 相似文献
8.
莺歌海盆地中深层发育高温高压气藏,由于晚期快速沉降和快速沉积形成了巨厚的欠压实泥岩。受高温高压特殊成藏的影响,位于莺歌海盆地中央泥底辟构造带西南面的东方X区高温高压储层的地震反射特征十分复杂,欠压实泥岩的存在直接影响地震亮点,造成该区地震亮点指示作用失效。受高温高压复杂地质情况的影响,直接应用常规的烃类检测方法存在一定的问题,因此,首先分析了东方X区的岩石物理特性,发现欠压实效应是影响该区烃类检测技术的关键因素,继而利用欠压实条件下的叠前反演方法以及分频成像方法对东方X区进行了烃类检测。实例分析表明,本方法能够有效识别和预测出该区含气目标,为该区的进一步勘探开发布井提供一定的依据。 相似文献
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10.
以济南市章丘区小冶睦里地区石炭二叠纪含煤地层采空区为研究对象,采取资料收集、井间地震、钻探验证等方法手段,分析井间地震层析成像技术对采空区解译推断的有效性。结果表明,井间地震层析成像速度反演结果体现为高速分布的区域,推断为基岩完整区域;速度反演结果体现为低速分布的区域,推断为采煤采空区域。经与钻探工程比对,井间地震层析成像技术推断的采空区位置与钻探揭露深度较为吻合,表明井间地震层析成像技术在济南市章丘区小冶睦里煤矿采空区勘查中具有较高的可行性和实用性,为该地区同类型的采空区勘查提供了参考依据。 相似文献
11.
以厦门某海底隧道勘察为靶区，采用电磁气泡震源系统激发地震波，在火成岩发育区进行水域地震映像实验，较好地查明了海底水深界面、淤泥（砂层）和基岩面的分界线。实验结果表明，水域地震映像法对海域火成岩发育区是一种有效的物探方法，可以为海域地质勘察提供可靠的地质参考依据；利用水域地震映像勘探既可以较好地弥补钻探缺陷，又能极大地节约经济成本。 相似文献
12.
X气田位于东海盆地西湖凹陷中央反转构造带,主要目的层H4层为浅水三角洲沉积环境,气田地震资料主频较低（25 Hz）,而H4层埋深较大（3 300~3 400 m）,储层低孔低渗,常规地震反演预测砂体厚度吻合度较低。针对X气田三维地震资料全覆盖及钻井较少的特点,通过地质模式指导下的正反演结合设置虚拟井来弥补SVR（Support Vector Regression）算法中样本点的不足,通过提取地震属性并优选表征砂体厚度的敏感属性,利用SVR算法进行多属性融合,完成了H4层砂体的定量预测。基于储层预测成果,提出H4层为浅水三角洲曲流型分流河道沉积,并进一步完成了砂体沉积模式解剖,成功指导了开发调整井部署,实钻砂体厚度与预测砂体厚度吻合度高达84%以上。探索得到了海上少井条件下地质模式约束的SVR算法储层定量预测方案,对X气田中深层分流河道储层完成了精准预测,亦对同类型油气田的储层描述具有一定指导意义。 相似文献
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14.
《世界地质(英文版)》2016,(1):6-12
Porosity is one of the most important properties of oil and gas reservoirs. The porosity data that come from well log are only available at well points. It is necessary to use other method to estimate reservoir porosity.Seismic data contain abundant lithological information. Because there are inherent correlations between reservoir property and seismic data,it is possible to estimate reservoir porosity by using seismic data and attributes.Probabilistic neural network is a powerful tool to extract mathematical relation between two data sets. It has been used to extract the mathematical relation between porosity and seismic attributes. Firstly,a seismic impedance volume is calculated by seismic inversion. Secondly,several appropriate seismic attributes are extracted by using multi-regression analysis. Then a probabilistic neural network model is trained to obtain a mathematical relation between porosity and seismic attributes. Finally,this trained probabilistic neural network model is implemented to calculate a porosity data volume. This methodology could be utilized to find advantageous areas at the early stage of exploration. It is also helpful for the establishment of a reservoir model at the stage of reservoir development. 相似文献
15.
徐家围子断陷火山岩岩性种类多,岩性复杂,不同岩性岩石特征差异大,火山岩岩性、储层的地震预测难度大,亟待通过岩石物理的分析,有效指导火山岩储层地震预测。通过对13种弹性参数敏感性交会分析,首次利用密度和剪切模量将徐家围子断陷营城组复杂火山岩岩性划分为玄武岩类、安山岩类和流纹岩类3类,且同一岩类岩性都具有相同的储层参数特征,在区分岩性基础上,利用密度和纵波速度双参数可对3类岩性组的储层进行直接识别,为火山岩储层叠前反演预测技术提供理论基础。 相似文献
16.
17.
波阻抗约束反演技术探测煤厚方法初探 总被引：1，自引：0，他引：1
现代化矿井生产技术日新月异,尤其对煤层厚度的探明程度要求越来越高。综合利用地质钻探和测井等资料,与地震资料有机结合而产生的具有高分辨率的新方法,发挥了钻探、测井和地震勘探技术各自的优势,实现了不同技术之间取长补短并提取地震属性参数,通过波阻抗约束反演可获得煤层厚度参数,达到对煤层厚度进行预测的目的。 相似文献
18.
海塔盆地中部断陷带反转构造特征及其对油气的控制 总被引：2，自引：0，他引：2
为研究海塔盆地中部断陷带反转构造的类型、分布、形成机制、与油气藏的关系及成藏模式和控藏特征,分析地震、油气藏开发及地球化学等资料.结果表明:伊敏组晚期,海塔盆地中部断陷带在近东西向压扭应力场作用下发生大规模反转,形成断层型、褶皱型和混合型3类5个亚类反转构造,并与上部含油气系统的大二段次生油气藏具有良好耦合关系.大二段次生油气藏为反转期原生油气藏沿主干反转断裂向上调整形成,以南一中段及下段烃源岩形成的原生油气藏为源,以大二段砂岩为储层,以伊敏组泥岩为盖层,以主反转断层为疏导为成藏模式;该次生油气藏的形成与反转程度密切相关,主要形成于反转程度较弱的塔南凹陷隐伏断展型反转构造发育的区域,北北东向的隐伏断展型反转构造圈闭是寻找该类次生油气藏的首选目标. 相似文献
19.
为了调查内蒙古阿拉善某高放废物地质处置库预选场址中目标花岗岩体的空间展布、内部结构和边界接触关系,应用人工反射地震探测技术,采集数据并进行处理,获得了针对大型高速岩体的近地表速度剖面和地震反射波法成像剖面。针对崎岖地表工区近地表速度建模与层析静校正、强散射干扰波压制等问题,引进基于MSFM射线追踪算法的初至波旅行时层析反演与层析静校正技术、改进的矢量分解压噪方法等,并在常规高分辨反射地震数据处理流程的基础上形成了适合于高速岩体地震探测的精细数据处理流程。 相似文献
20.
Gas hydrate research has significant importance for securing world energy resources, and has the potential to produce considerable
economic benefits. Previous studies have shown that the South China Sea is an area that harbors gas hydrates. However, there
is a lack of systematic investigations and understanding on the distribution of gas hydrate throughout the region. In this
paper, we applied mineral resource quantitative assessment techniques to forecast and estimate the potential distribution
of gas hydrate resources in the northern South China Sea. However, current hydrate samples from the South China Sea are too
few to produce models of occurrences. Thus, according to similarity and contrast principles of mineral outputs, we can use
a similar hydrate-mining environment with sufficient gas hydrate data as a testing ground for modeling northern South China
Sea gas hydrate conditions. We selected the Gulf of Mexico, which has extensively studied gas hydrates, to develop predictive
models of gas hydrate distributions, and to test errors in the model. Then, we compared the existing northern South China
Sea hydrate-mining data with the Gulf of Mexico characteristics, and collated the relevant data into the model. Subsequently,
we applied the model to the northern South China Sea to obtain the potential gas hydrate distribution of the area, and to
identify significant exploration targets. Finally, we evaluated the reliability of the predicted results. The south seabed
area of Taiwan Bank is recommended as a priority exploration target. The Zhujiang Mouth, Southeast Hainan, and Southwest Taiwan
Basins, including the South Bijia Basin, also are recommended as exploration target areas. In addition, the method in this
paper can provide a useful predictive approach for gas hydrate resource assessment, which gives a scientific basis for construction
and implementation of long-term planning for gas hydrate exploration and general exploitation of the seabed of China. 相似文献