Early Cenozoic paleontological assemblages and provenance evolution of the Lishui Sag,East China Sea

The East China Sea Shelf Basin generated a series of back-arc basins with thick successions of marine- and terrestrial-facies sediments during Cenozoic. It is enriched with abundant oil and gas resources and is of great significance to the petroleum exploration undertakings. Therein, the Lishui Sag formed fan delta, fluvial delta and littoral-to-neritic facies sediments during Paleocene–Eocene, and the research on its sedimentary environment and sediment source was controversial. This study analyzed the paleontological combination characteristics, and conducted a source-to-sink comparative analysis to restore the sedimentary environment and provenance evolution of the Lishui Sag during Paleocene–Eocene based on the integration of detrital zircon U-Pb age spectra patterns with paleontological assemblages. The results indicated that Lishui Sag was dominated by littoral and neritic-facies environment during time corroborated by large abundance of foraminifera, calcareous nannofossils and dinoflagellates. Chronological analysis of detrital zircon U-Pb revealed that there were significant differences in sediment sources between the east and west area of the Lishui Sag. The western area was featured by deeper water depths in the Paleocene–Eocene, and the sediment was characterized by a single Yanshanian peak of zircon U-Pb age spectra, and mainly influenced from Yanshanian magmatic rocks of South China Coast and the surrounding paleo-uplifts. However, its eastern area partly showed Indosinian populations. In particular, the upper Eocene Wenzhou sediments were featured by increasingly plentiful Precambrian zircons in addition to the large Indosinian-Yanshanian peaks, indicating a possible impact from the Yushan Low Uplift to the east. Therefore, it is likely that the eastern Lishui Sag generated large river systems as well as deltas during time. Due to the Yuquan Movement, the Lishui Sag experienced uplifting and exhumation in the late stage of the late Eocene and was not deposited with sediments until Miocene. Featured by transitional-facies depositions of Paleocene–Eocene, the Lishui Sag thus beared significant potential for source rock and oil-gas reservoir accumulation.     

天然气水合物的地球物理识别标志

地球物理标志是天然气水合物识别标志的重要组成部分,包括测井识别标志和地震识别标志两个方面。系统地总结了含天然气水合物沉积层在电阻、电位、井径、声波、密度、中子和成像测井等方面的测井异常,常规剖面和属性剖面上的地震响应异常,以及东海海域的地球物理异常特征,旨在为我国天然气水合物地球物理识别技术的研究提供基础材料。     

现代黄河三角洲滨浅海区的灾害地质

利用卫星遥感、测深、浅地层剖面及钻孔资料研究了黄河三角洲海岸及近海海洋灾害地质,编制了黄河三角洲海洋灾害地质图。黄河三角洲海岸灾害地质以海岸侵蚀为主,根据1976—2001年海岸的变化速率,可将海岸分为快速侵蚀海岸、中等程度侵蚀海岸、稳定海岸和淤积海岸四类,快速侵蚀海岸和中等程度侵蚀海岸长期以来遭受侵蚀。灾害地质因素有浅层气、灾害地貌、活动断层、海底滑坡、底辟、隆起脊、埋藏冲沟一古河道。浅层气主要分布在老黄河口附近渤海海底,近岸少见。浅层灾害地貌主要分布在三角洲前缘斜坡上的扰动区。扰动区位置在整个三角洲上变动明显,有向岸移动的趋势,斜坡坡度减小,扰动强度减弱。底辟除了发生在废弃三角洲侵蚀区外,还发生在三角洲外的渤海海底下部。隆起脊位于黄河口东部渤海海底,沿NE—SW方向发育,顺隆起脊发育活动断层。     

苏北盐城凹陷天然气与凝析油的成因机制

盐城凹陷天然气中甲烷含量高,碳同位素具有正分布系列,主体具有高成熟腐泥型气特征,伴随产出的凝析油则体现出与本区湖相原油和海相原油既相似又相区别的特征。不同组分间存在成熟度差异,轻质组分反映高成熟,中等组分体现出未熟低熟,重质组分表现出成熟特征。母源分析对比表明天然气与凝析油主要源自古生界海相腐泥型源岩,混有泰州组少许贡献,造成组分差异和成熟度变化的重要原因是大量气体注入配以长期发育断裂引起的运移分馏和不同成熟度油气混合所致。     

油气勘探中的碳酸盐岩古岩溶研究方法综述

检索了国内外相关文献,重新阐述了古岩溶的概念,同时介绍了岩溶研究进展情况。在此基础上,对国内外学者关于古岩溶研究的方法和技术手段进行总结,分析了几种主要方法的优点和不足之处,并对今后岩溶研究思路和方法提出建议。      

试论煤层气藏概念与成藏要素

通过对前人煤层气藏概念的调研和对煤层气性质及成藏要素的研究, 认为: 煤层气藏是在压力封闭作用下, 吸附煤层气达到相当数量的煤岩体或煤层, 是煤层气聚集和煤层气勘探开发的基本地质单元。煤层气藏的成藏要素主要包括煤层条件、压力封闭和保存条件。煤层条件是煤层气藏形成的物质基础, 压力封闭是煤层气藏的必要条件, 保存条件是煤层气藏从形成到现今能够存在的前提。      

基于神经网络的煤与瓦斯突出矿井等级划分方法

针对我国煤炭行业中对突出矿井同一定级, 实施同一安全管理的现象, 从分析工作系统的灾害模型出发, 给出了突出矿井等级划分的评价指标体系, 应用灰色系统和证据理论的方法给出了神经网络训练的样本。在此基础上, 提出了危险信度的概念, 用以衡量突出矿井危险程度, 编制了神经网络, 并对其进行训练。应用训练好的神经网络, 对淮南矿区的几个突出矿井进行了工程验证。该方法对建立健全我国突出矿井的划分方法及评价标准具有一定指导意义。      

地震油气储层的小样本卷积神经网络学习与预测

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.     

垂直气柱中大气微量成分总含量的反演

提出了一种利用地面中等光谱分辨率的太阳红外光谱反演整层大气中某几种微量成分总含量的方法,用逐线积分（ Ｌ Ｂ Ｌ） 法计算整层大气分子吸收,采用差分吸收法测量太阳红外光谱得到实际大气中微量成分的吸收,用最大似然法反演出微量成分的总量。详细分析了这种方法的可行性和反演精度,数值模拟分析和实际测量表明该方法有较高的精度,已把该方法用于监测实际大气中甲烷和水汽总含量的变化。