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131.
渤海结冰海区溢油行为数值模拟   总被引:6,自引:2,他引:4  
基于溢与海冰,水,大气的相互作用原理,建立了渤海结冰海区溢油行为数据模式,该模式模拟子结冰海区中油的输运过程,与国外有关模式相比更加重视冰场和冰速场的作用。海冰及潮流模式及采被实况检验过的渤海海冰数值预报模式。  相似文献   
132.
Adaptation to sublethal exposure to crude oil by phytoplankton is poorly understood. Use of chemical dispersants for oil spill remediation increases petroleum hydrocarbon concentrations in water, while exposing marine organisms to potentially toxic concentrations of dispersant. Heat shock proteins (hsps) have been found to serve as an adaptive and protective mechanism against environmental stresses. The objective of this project was to examine the induction of hsps in Isochrysis galbana, a golden-brown algae, following exposure to the water-accommodated fraction (WAF) of Prudhoe Bay crude oil (PBCO) and PBCO chemically dispersed with Corexit 9527® (dispersed oil: DO). Initial experiments using 35S-labeled amino acids and 2-dimensional electrophoresis with subsequent western blotting identified and confirmed hsp60, a member of the chaperonin family of stress proteins, as being efficiently induced by heat shock in this species. One-dimensional SDS PAGE and western blotting, with hsp60 antibodies and chemiluminesence detection, were used to quantitate hsp60 following exposure to a range of environmental temperatures and concentrations of WAF and DO preparations. I. galbana cultured in 22 parts per thousand (‰) salinity showed a statistically significant increase (p<0.05) in hsp60 after exposure to 25, 30, and 35°C for 1 h compared to controls (20°C), while 34‰ cultures showed no significant increase in hsp60 with increasing temperature. Cultures (22 and 34‰) exposed to varying doses of WAF and DO exhibited statistically significant (p<0.05) increases in levels of hsp60 in all cases. A dose-related response was observed in all exposures (r2≥0.90) with the exception of 34‰ WAF. In independent exposures, a dose-related hsp60 response to naphthalene, a relatively abundant water-soluble aromatic hydrocarbon, was observed in both 22 and 34‰ cultures. Results of this study are consistent with previous studies in other species documenting increases in hsp60 levels with exposure to xenobiotics. Further studies are investigating the protective function of hsp60 against the toxic effects of exposure to WAF and DO preparations.  相似文献   
133.
石油企业抗震防灾规划信息管理系统的设计   总被引:1,自引:0,他引:1       下载免费PDF全文
基于石油企业抗震防灾工作对网络与数据库的信息管理系统的需求,对数据库产品进行了简要分析,并根据石油企业抗震防迷规划的需求和信息管理的一般模式,提出了石油企业抗震防灾规划信息计算机管理系统的设想。认为,以Microsoft Access数据库软件为基础,利用VB或VC等可视化前端应用开发工具,是目前比较好的方案,它将使石油企业抗震防灾规划工作在办公自动化方面迈向新的台阶。  相似文献   
134.
激光诱导荧光(LIF)是一种主动光学探测技术,该技术已在海面未乳化溢油油种鉴别及油膜厚度评估方面取得了一定的研究成果,但乳化溢油的监测理论基础和探测方法尚未成熟。溢油乳化物的量化会直接影响溢油污染的应急处理和灾害评估,但目前对溢油乳化液溢油量的计算尚未有研究报道。本文以水包油乳化液为研究对象,基于等效思想,根据油量相等建立了水包油乳化液与油膜的荧光检测等效模型,并依据光的辐射传输机理推导出等效油膜厚度的估算公式,最后采用仿真实例对估算方法的适用性和有效性进行了验证。实验结果表明,当水包油乳化液含油率小于12×10-6,厚度小于5.98 cm时,利用所提出的等效方法能有效计算出水包油实际溢油厚度。该方法可为海面乳化溢油量的估算提供一种创新性的方法,具有良好的借鉴意义和实际应用价值。  相似文献   
135.
地震油气储层的小样本卷积神经网络学习与预测   总被引:2,自引:0,他引:2       下载免费PDF全文
地震储层预测是油气勘探的重要组成部分,但完成该项工作往往需要经历多个环节,而多工序或长周期的研究分析降低了勘探效率.基于油气藏分布规律及其在地震响应上所具有的特点,本文引入卷积神经网络深度学习方法,用于智能提取、分类并识别地震油气特征.卷积神经网络所具有的强适用性、强泛化能力,使之可以在小样本条件下,对未解释地震数据体进行全局优化提取特征并加以分类,即利用有限的已知含油气井段信息构建卷积核,以地震数据为驱动,借助卷积神经网络提取、识别蕴藏其中的地震油气特征.将本方案应用于模型数据及实际数据的验算,取得了预期效果.通过与实际钻井信息及基于多波地震数据机器学习所预测结果对比,本方案利用实际数据所演算结果与实际情况有较高的吻合度.表明本方案具有一定的可行性,为缩短相关环节的周期提供了一种新的途径.  相似文献   
136.
Raindrops falling on the sea surface produce turbulence. The present study examined the influence of rain-induced turbulence on oil droplet size and dispersion of oil spills in Douglas Channel in British Columbia, Canada using hourly atmospheric data in 2011–2013. We examined three types of oils: a light oil (Cold Lake Diluent - CLD), and two heavy oils (Cold Lake Blend - CLB and Access Western Blend - AWB). We found that the turbulent energy dissipation rate produced by rainfalls is comparable to what is produced by wind-induced wave breaking in our study area. With the use of chemical dispersants, our results indicate that a heavy rainfall (rain rate > 20 mm h? 1) can produce the maximum droplet size of 300 μm for light oil and 1000 μm for heavy oils, and it can disperse the light oil with fraction of 22–45% and the heavy oils of 8–13%, respectively. Heavy rainfalls could be a factor for the fate of oil spills in Douglas Channel, especially for a spill of light oil and the use of chemical dispersants.  相似文献   
137.
138.
孙健  胥亚  陈方玺  彭仲仁 《海洋学报》2014,36(9):103-105
海洋油污染是各类海洋污染中最常见、分布面积最广且危害程度最大的污染之一。近年来,海洋特别是近海人类活动频繁,且随着海上运输和石油加工业的发展,油田井喷、钻井平台爆炸、船舶碰撞等所造成的溢油事故增多,因而,监测海洋溢油具有重要的经济和社会现实意义。研究采用MatLAB工具,通过图像预处理(图像校正和增强)、特征提取和神经网络识别等方法,对合成孔径雷达(SAR)海洋溢油图像进行处理,最终期望实现半自动区分SAR图像上各类目标,并进行多种神经网络方法效果比较。研究首先对SAR海洋溢油图像进行初步人工识别;然后进行图像预处理(几何校正、滤波处理等)和基于灰度共生矩阵的特征值计算;最后,借助神经网络方法对溢油区域和疑似溢油区域进行分类,输出分类处理后的图像。通过输出图像分析发现,神经网络能对SAR海洋溢油图像中溢油、海水、土地3类目标进行明确分类,且RBF神经网络模型精度高于BP神经网络。本文提出的半自动分类方法不仅能提高SAR图像处理效率,将分类目标扩充有溢油和非溢油扩充到溢油、海水、土地3类,提高图像处理的全面性,同时通过比较RBF和BP神经网络在SAR溢油图像分类上的具体优劣,有着较好实际意义。  相似文献   
139.
《China Geology》2020,3(4):633-642
Oil and gas resources are short in Pakistan and no commercially viable oil and gas sources have been yet discovered in its offshore areas up to now. In this study, the onshore-offshore stratigraphic correlation and seismic data interpretation were conducted to determine the oil and gas resource potential in the Offshore Indus Basin, Pakistan. Based on the comprehensive analysis of the results and previous data, it is considered that the Cretaceous may widely exist and three sets of source rocks may be developed in the Offshore Indus Basin. The presence of Miocene mudstones has been proven by drilling to be high-quality source rocks, while the Cretaceous and Paleocene–Eocene mudstones are potential source rocks. Tectonic-lithologic traps are developed in the northwestern part of the basin affected by the strike-slip faults along Murray Ridge. Furthermore, the Cretaceous and Paleocene–Eocene source rocks are thick and are slightly affected by volcanic activities. Therefore, it can be inferred that the northwestern part of Offshore Indus Basin enjoys good prospects of oil and gas resources.  相似文献   
140.
《China Geology》2020,3(4):575-590
The sequence stratigraphic framework of Shanxi Formation in the northeast Zhoukou Depression was established based on detailed sequence stratigraphical and sedimentological analysis by utilizing the logging and core data of six wells drilled in the eastern tectonic unit of Zhoukou Depression. It was divided into three third-order sequences, namely SQs1, SQs2, and SQs3 from bottom to top. Each sequence can be divided into a transgressive system tract (TST) and a highstand system tract (HST). Furthermore, four sequence boundaries and three maximum flooding surfaces were identified, and they are the bottom interface SBs and maximum flooding surface mfss1 of SQs1, the bottom interface SBs1 and maximum flooding surface mfss2 of SQs2, the bottom interface SBs3 and maximum flooding surface mfss3 of SQs3, and the top interface SBx from bottom to top. Carbonate tidal flat –clastic tidal flat sedimentary system developed in Shanxi Formation in the northeast Zhoukou Depression (also referred to as the study area) under the control of regression. Meanwhile, four sedimentary microfacies were identified in the sedimentary system, which are lime-mud flats, sand flats, mixed flats, and mud flats. The transgression in the study area occurred from the southeast to the northwest. Therefore, the northwestern part is the seaward side, and the southeastern part is the landward side. As revealed by relevant drilling data, SQs1 of the Shanxi Formation is characterized by the development of limestone and carbonaceous mudstone, with limestone, dark mudstone, and carbonaceous mudstone mainly developing. Meanwhile, lime-mud flats were mainly deposited in it. During the periods of SQs2 and SQs3, the sedimentary environment of the study area changed from the carbonate tidal flats to clastic tidal flats as the coastline migrated towards the sea. In these periods, sand flats mainly developed near the maximum flooding surfaces and were relatively continuous in the eastern and southern parts of the transgressive system tract; mixed flats were relatively continuous in the western and northern parts of the transgressive system tract as well as the eastern and southern parts of the highstand system tract; mud flats widely developed in the highstand system tract. Peat flats mainly developed in the period of HSTs2, with coal seams relatively developing in the southeastern part of the study area as revealed by drilling data. The peat flats in SQs2 are favorable hydrocarbon source layers, the lime-mud flats in SQs1 and sand flats formed in the transgression periods of SQs2 and SQs3 constitute favorable hydrocarbon reservoirs, and the mud flats form in the transgressions periods serve as favorable cap rocks. Therefore, the study area features a reservoir-cap assemblage for self-generating and self-storing of hydrocarbon, and the southeastern part of the study area can be taken as a favorable exploration area.  相似文献   
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