一种板内小尺度走滑断层平面分段研究方法——以塔里木盆地顺北5号断层中北段为例     

林波  云露  张旭  肖重阳  况安鹏  徐学纯  曹自成 《吉林大学学报(地球科学版)》2021,51(4):1006-1018

近年来在顺北地区1号和5号走滑断层带上获得了重大的油气突破,证明了在塔里木盆地内发育的小尺度走滑断层对断控油气藏具有控藏、控储的特征。该类走滑断层在剖面上贯穿多套古生代地层,纵向结构复杂,在空间上为深层线性走滑叠加浅层雁列正断层的构造样式,钻井揭示在断层带上不同分段的井产能差异明显,表明走滑断层在奥陶系碳酸盐岩顶界面的分段性对油气成藏具有重要的控制作用。本文选取顺北5号断层中北段作为研究对象,针对深层不同层系线性走滑断层分段特征差异明显这一特征,基于不同尺度下断层的断距与分段长度之间的相关性及多断层演化理论,提出了利用沿着走向等间距统计断层的垂向断距变化的方法对深层线性走滑断层开展分段性研究工作,该方法综合了断层的活动强度、演化程度和剖面构造形态来分析断层的分段特征,适用于不同性质的断层分段性特征研究。研究表明5号断层中北段在奥陶系碳酸盐岩顶界面可划分为14段,在寒武系膏盐岩层顶界面可划分为10段,两个层系的断层分段性在空间上具有继承性与差异演化的特点,其中寒武系膏盐岩滑脱构造中的膏盐逃逸对油气的疏导具有破坏作用,奥陶系碳酸盐岩顶断层活动强度、分段叠接样式、断层分段不同位置对断控缝洞型储层发育规模具有重要的控制作用,揭示了断层在平面上的分段特征及纵向结构对断控缝洞型油气成藏具有重要的控制作用。  相似文献   

Spatial patterns of phytoplankton communities in an International Seabed Authority licensed area (COMRA,Clarion-Clipperton Zone) in relation to upper ocean biogeochemistry     

Yu Wang  Aiqin Han  Xuebao He  Fangfang Kuang  Feng Zhao  Peng Xiang  Kuidong Xu 《海洋学报(英文版)》2022,41(11):45-57

The Clarion-Clipperton Zone (CCZ) hosts one of the largest known oceanic nodule fields worldwide and is regulated by the International Seabed Authority. A baseline assessment of diversity and distribution patterns is essential for reliable predictions of disturbed ecosystem response scenarios for sustained commercial activities in the future. In the present study, the spatial patterns and diversity of phytoplankton communities were analyzed along with upper ocean biogeochemistry, in the licensed China Ocean Mineral Resources R&D Association (COMRA) contract area and the surrounding western CCZ between August 21 and October 8, 2017. Results indicated this was a typical low-nutrient low-chlorophyll a (Chl a) environment, characterized by low levels of phytoplankton abundance and diversity. In total 112 species belonging to 4 phyla were recorded (>10 μm), with species counts including 82 diatoms, 27 dinoflagellates, 1 cyanobacteria and 2 chrysophyte. Dominant taxa in successive order of descending abundance and occurrence included Nizschia marina, Cyclotella stylorum, Dactyliosolen mediterraneus, Rhizosolenia setigera, Pseudo-nitzschia delicatissima, Thalassiothrix frauenfeldii, Synedra sp., Chaetoceros simplex and Pseudo-nitzschia circumpora. The depth-averaged abundance and Chl a concentrations were (265±233) cells/L and (0.27±0.30) μg/L, respectively. Diatoms accounted for 90.94% of the community with (241±223) cells/L, while dinoflagellates accounted for 5.67% and (15±13) cells/L. The distribution pattern exhibited the same trend as abundance, Chl a and species richness, showing subsurface maximum levels at around 100 m, with stations near 10°N having higher levels than in the north. Cluster analysis was performed in two assemblages, relating to geographic locations to the south and north of 12°N. The subsurface maximum of abundance, Chl a, species richness, dissolved oxygen and nitrite were generally corresponding to the presence of high salinity North Pacific Central Water at depths of 50?120 m. Higher availability of nitrate, phosphate and silicic acid in the subsurface may account for the shift in phytoplankton distribution, as shown by redundancy correspondence and spearman correlation analysis. Diel variation in an anchor station demonstrated prominent species succession without significant differences in oceanographic variables, among which diatoms succession resulted from the light limitation, while dinoflagellate diel variation mainly related to lateral transport of water masses. The observed patchiness in spatial phytoplankton distributional patterns was attributed to upper ocean environmental gradients in the CCZ. The baseline generated in this study could be analyzed using current conservation strategy programs associated with deep-sea mining.  相似文献   

中国城市土地绿色利用效率驱动因素及空间分异   总被引：1，自引：0，他引：1  

卢新海  李佳  刘超  匡兵  蔡大伟  侯娇 《地理科学》2022,42(4):611-621

以2009—2018年中国285个地级及以上城市为研究对象,测算各城市的城市土地绿色利用效率,对其驱动因素的空间异质性进行探究与分区。结果表明：① 城市土地绿色利用效率总体呈波动上升趋势,集聚特征显著,省际、省内差异明显;区域上,呈现西部＞东部＞中部的格局;规模等级上,随着城市规模等级降低而递增。② 城市土地绿色利用效率是众多因素交互驱动的结果,且各驱动因素均具有明显的空间异质性特征,呈现出空间带状或片状分布规律。③ 根据城市土地绿色利用效率驱动因素的空间异质性特征,可划分为产业结构高级化、环境规制和科技投入水平主导的东南地区;生态资源禀赋主导的华北地区;经济发展水平、城市空间集聚主导的西南地区;土地市场化主导的西北地区;人口集聚、土地财政、基础设施水平主导的东北地区。未来应因城施策、因地制宜,采取差异化的措施来提升城市土地绿色利用效率。  相似文献   

钦州对虾养殖灾害性天气分析和气象服务要领   总被引：1，自引：0，他引：1  

农成万  张幸  李斌喜  邝良俊  陈思 《气象研究与应用》2013,34(1):60-63

利用钦江农场养虾基地提供的养殖数据,结合钦州的天气气候资料,从气象角度分析得到,影响钦州对虾养殖主要有五个气象要素和三大灾害性天气,并提出防灾措施和进行虾业气象服务所应掌握的要点和要领。  相似文献   

山东郯城和江苏东海早白垩世晚期恐龙足迹化石新发现及古环境^*   总被引：2，自引：0，他引：2       下载免费PDF全文

汪明伟  旷红伟  柳永清  彭楠  刘海  吴清资  徐加林  陈军  许欢 《古地理学报》2013,15(4):489-504

首次在山东郯城早白垩世晚期地层中发现恐龙足迹化石,分属蜥脚类和兽脚类恐龙足迹,足迹大小差异较大。通过对山东省郯城县新发现的2处恐龙足迹化石点和江苏省东海县南古寨恐龙足迹化石点的对比研究,探讨了足迹类型、大小、速度与足迹深度的关系,发现同等条件下,蜥脚类恐龙足迹通常较兽脚类足迹深,而蜥脚类恐龙足迹深度随着足迹大小的增加有变深的趋势;波痕、雨痕和泥裂等沉积构造以及足迹回填和叠覆现象对足迹化石保存形态和细节有较大影响,而构造变形对足迹形态和行迹并无明显影响,但高角度的构造变形会加速差异风化,使足迹化石更易暴露而被破坏。对研究区古环境与古生态的研究表明,早白垩世晚期研究区经历了水体逐渐变浅、气候由湿到干并伴随短暂间歇性干旱的过程,沉积环境由河湖演变为三角洲前缘、并逐渐过渡到三角洲平原,生态环境逐渐恶化,动植物由兴而衰、逐渐减少。  相似文献   

Physicochemical and biological interfacial interactions: impacts on soil ecosystem and biodiversity     

Pan Ming Huang  Shan-Li Wang  Yu-Min Tzou  Yibin Huang  Boqi Weng  Shunyao Zhuang  Ming Kuang Wang 《Environmental Earth Sciences》2013,68(8):2199-2209

Soil is a vital biological habitat, which is of primary importance in determining and regulating biological activity and biodiversity. Therefore, it is Earth’s most important resource in sustaining both belowground and aboveground biological activities. Biodiversity versus landscape diversity and land use practices in multifunctional landscapes have been addressed. Humans have so manipulated nature that few locations in the world remain without human influence, causing unforeseen changes in ecosystem continuously and biodiversity. Among the environmental compartments, about 90 % of environmental pollutants are bound with soil particles. The soil-bound pollutants may be released to the soil solution through physical, chemical and biological interfacial interactions and pose a threat to biodiversity and ecosystem integrity. These interfacial interactions are especially important in the rhizosphere, where the kinds and concentrations of biomolecules are different from the bulk soil because of intense biological activity. These biomolecules affect biogeochemical processes, soil microbial ecology, nutrient and contaminant dynamics, abiotic and biotic factors, and soil biodiversity through allelopathic interactions. Soil interfacial interactions under different pedogenic processes and anthropogenic activity in relation to belowground biodiversity and the impact on aboveground biodiversity, productivity and integrity should be an important and exciting area of science for years to come.  相似文献   

近红外漫反射光谱在沉积物化学成分分析中的研究进展     

尚文郁  孙青  凌媛  谢曼曼  岑况 《岩矿测试》2012,31(4):582-590

沉积物中有机质及相关元素含量、重金属含量等是研究环境污染和古环境的依据。利用近红外漫反射光谱测定沉积物中的化学成分,方法简便、快捷、价廉。本文概述了近红外漫反射光谱测定沉积物中化学成分的基本流程、样品制备及建模方法,介绍了如何通过选择建模样品、利用光谱预处理及回归分析等方法提高近红外光谱模型的定量能力,综述了近红外漫反射光谱分析沉积物中的有机碳、总氮、总磷、生物硅、重金属含量等方法。但是利用近红外光谱分析沉积物中的化学成分研究起步较晚,仍存在很多问题,有必要深入探讨近红外光谱分析沉积物的化学成分时产生误差的机理,进一步开展建模样品的计算机选择方法、光谱预处理方法和数学模型优化等方面的研究,提高近红外漫反射光谱分析沉积物中化学成分的精密度和准确度。  相似文献   

5A分子筛吸附混合溶剂洗脱-气相色谱-同位素质谱分析土壤中正构烷烃单体碳同位素     

张逐月  刘美美  谢曼曼  王道聪  凌媛  尚文郁  刘舒波  岑况  孙青 《岩矿测试》2012,31(1):178-183

利用5A分子筛吸附,环己烷-正戊烷混合溶剂洗脱分离富集正构烷烃,用气相色谱法测定正构烷烃含量,气相色谱-气体同位素质谱(GC-C-IRMS)测定土壤样品中正构烷烃单体碳同位素。实验优化了5A分子筛用量和洗脱剂的比例,需要络合的正构烷烃的量与分子筛加入量呈线性关系,络合x mg的正构烷烃,需加入2.75x g分子筛,络合环己烷-正戊烷最佳比例为9∶91。探讨了络合过程中5A分子筛对不同链长正构烷烃的络合规律,短链正构烷烃被5A分子筛优先吸附,长链正构烷烃的络合相对滞后。正构烷烃的络合洗脱回收率为44%～72%,精密度(RSD,n=6)为4%～8%;正构烷烃单体碳同位素分析精度为0.04‰～0.38‰(1σ)。采用5A分子筛净化混合溶剂洗脱方法,分析加油站附近的实际土壤样品,未分峰基本消除,获得良好的净化效果,满足正构烷烃单体碳同位素分析的要求。  相似文献   

北京市PM_(2.5)中主要重金属元素污染特征及季节变化分析   总被引：3，自引：0，他引：3  

于扬  岑况  Stefan Norra  Nina Schleicher  陈媛 《现代地质》2012,26(5):975-982

利用2005年4月18日—2008年9月27日北京市中国地质大学(东门)采样点的PM2.5质量浓度变化与重金属Cd、Pb、As、Cu及Zn等污染特征,结合最新发布的《环境空气质量标准》(GB3095—2012),初步分析了近4年时间里北京市单点PM2.5的污染水平及主要重金属污染元素的变化特征,得出了一些有意义的认识。2005年春季—2008年春季期间PM2.5质量浓度为13.1～171μg/m3之间变化,平均浓度为65.6μg/m3,超过最新环境空气质量标准制定的PM2.5年平均浓度限值35μg/m3,北京市PM2.5污染形势依然严峻。奥运会及残奥会期间PM2.5的24 h质量浓度平均值为40.7μg/m3,没有超标。北京市PM2.5中的重金属元素含量及富集特征随着不同年份不同季节差别较大,典型的城市污染元素As在冬季质量浓度最高。对比环境空气质量标准的参考浓度限值发现,As元素的质量浓度在研究期间的年均值均超过了年平均浓度参考限值0.006μg/m3。化学分析结果显示人为污染是PM2.5中Cu、Cd、Pb、Zn、As重金属污染的主要来源,其中As污染需要引起足够重视。研究结果对于北京市大气污染防治具有一定的借鉴意义。  相似文献   

Assessing the fidelity of surface currents from a coastal ocean model and HF radar using drifting buoys in the Middle Atlantic Bight     

Liang Kuang  Alan F. Blumberg  Nickitas Georgas 《Ocean Dynamics》2012,62(8):1229-1243

The rapid expansion of urbanization along the world’s coastal areas requires a more comprehensive and accurate understanding of the coastal ocean. Over the past several decades, numerical ocean circulation models have tried to provide such insight, based on our developing understanding of physical ocean processes. The systematic establishment of coastal ocean observation systems adopting cutting-edge technology, such as high frequency (HF) radar, satellite sensing, and gliders, has put such ocean model predictions to the test, by providing comprehensive observational datasets for the validation of numerical model forecasts. The New York Harbor Observing and Prediction System (NYHOPS) is a comprehensive system for understanding coastal ocean processes on the continental shelf waters of New York and New Jersey. To increase confidence in the system’s ocean circulation predictions in that area, a detailed validation exercise was carried out using HF radar and Lagrangian drifter-derived surface currents from three drifters obtained between March and October 2010. During that period, the root mean square (RMS) differences of both the east–west and north–south currents between NYHOPS and HF radar were approximately 15 cm s^?1. Harmonic analysis of NYHOPS and HF radar surface currents shows similar tidal ellipse parameters for the dominant M₂ tide, with a mean difference of 2.4 cm s^?1 in the semi-major axis and 1.4 cm s^?1 in the semi-minor axis and 3° in orientation and 10° in phase. Surface currents derived independently from drifters along their trajectories showed that NYHOPS and HF radar yielded similarly accurate results. RMS errors when compared to currents derived along the trajectory of the three drifters were approximately 10 cm s^?1. Overall, the analysis suggests that NYHOPS and HF radar had similar skill in estimating the currents over the continental shelf waters of the Middle Atlantic Bight during this time period. An ensemble-based set of particle tracking simulations using one drifter which was tracked for 11 days showed that the ensemble mean separation generally increases with time in a linear fashion. The separation distance is not dominated by high frequency or short spatial scale wavelengths suggesting that both the NYHOPS and HF radar currents are representing tidal and inertial time scales correctly and resolving some of the smaller scale eddies. The growing ensemble mean separation distance is dominated by errors in the mean flow causing the drifters to slowly diverge from their observed positions. The separation distance for both HF radar and NYHOPS stays below 30 km after 5 days, and the two technologies have similar tracking skill at the 95 % level. For comparison, the ensemble mean distance of a drifter from its initial release location (persistence assumption) is estimated to be greater than 70 km in 5 days.  相似文献