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871.
Guo  Naijing  Tang  Xiaolan  Ren  Yujie  Ma  Kun  Fang  Jinxiang 《GeoJournal》2021,86(2):689-710
GeoJournal - With the acceleration of urbanization, the unknown risks faced by cities and regions are also increasing, and their vulnerability is exposed, which has become a major problem hindering...  相似文献   
872.
任小庆 《地质与勘探》2021,57(2):423-429
高温地热钻井过程中,温度会对泡沫钻井液体系稳定性造成影响。针对高温地热井泡沫钻井液的技术要点,分别对发泡剂、稳泡剂、抗温土的优选,在此基础之上分别对泡沫钻井液的抗高温性能、抗污染能力进行了评价。实验结果表明:(1)优选出的发泡剂/聚合物/粘土体系在不同温度下进行测试,均具有良好的泡沫稳定性和发泡能力,说明初步形成的泡沫体系具有良好的抗230℃高温的能力。(2)通过模拟欠平衡钻进过程中地热水对泡沫钻井液体系的污染发现,该体系耐一价盐能达到20%,而且在加入5%CaCl_2后析液半衰期仍在5 min以上,最终形成一套抗高温能力可达230℃,具有较好悬浮携带能力的地热井抗高温环保钻井液体系。  相似文献   
873.
超深、超老地层中的非常规油气成藏及演化、甜点区刻画、资源潜力定量评价是非常规油气沉积学的一大难点,相关定量评价技术和理论的发展对推进我国“两深一非”油气勘探具有现实意义。沥青是古油藏存在的直接证据,对探索古油藏分布、规模、成藏机制及论证研究区油气勘探潜力具有重要理论和实践意义。以川中地区上震旦统灯影组灯四段为研究对象,先综合岩芯观察、铸体薄片镜下观察、图像法定量计算,对固态沥青进行了表征;而后建立了多矿物体积模型,借助常规测井曲线组合(DEN-RT-RXO-CNL-AC),对储层固态沥青进行反演,克服了储层固态沥青分布的强非均质性,定量评价了灯四段固态沥青的含量及分布。研究结果表明:1)灯四段沥青多以半充填状态存在于孔隙中,储层固态沥青含量可达4.62%,平均为2.20%;纵向上,灯四上亚段固态沥青含量普遍高于灯四下亚段;2)高石梯—磨溪地区与德阳—安岳裂陷槽紧邻的台缘礁滩体是古油藏聚集的有利区域,储层固态沥青含量普遍高于东侧的含气区;3)受自西向东油气充注控制,高石梯—磨溪地区南北向固态沥青含量无明显差异。古隆起北斜坡灯四段固态沥青的存在证实了北斜坡古油藏的存在,从侧面印证了北斜坡的油气成藏潜力。从固态沥青的角度,坚定了继续深化川中古隆起北斜坡深层、超深层油气勘探的必要性。  相似文献   
874.
攀西会理县白草矿区以钒钛磁铁矿而闻名,但该钒钛磁铁矿床中还发育一定规模的富钴硫化物矿石,对该类型矿石的形成机制研究还不深入.本文选择白草矿区产出的浸染状、致密块状、网脉状和斑杂状富钴硫化物矿石中的磁黄铁矿做为研究对象,在野外地质调查的基础上,通过矿相学和电子探针等方法对磁黄铁矿的成分和晶体类型进行研究.利用磁性胶体可以鉴别磁黄铁矿晶体类型的原理,确定了研究区的磁黄铁矿具有单斜磁黄铁矿(Mpo)和六方磁黄铁矿(Hpo)两种晶体类型,厘定了细脉状、叶片状和不规则状交生体.通过研究磁黄铁矿中各主量元素特征,计算了磁黄铁矿形成温度、硫逸度和M/S值等参数.将磁黄铁矿形成划分岩浆成矿期(熔离阶段、接触交代阶段)和热液成矿期,并初步厘定了4类磁黄铁矿生成顺序:首先形成浸染状矿石磁黄铁矿与致密块状矿石磁黄铁矿,其次形成斑杂状矿石磁黄铁矿,最后形成网脉状矿石磁黄铁矿.  相似文献   
875.
基于民航业特点及中国民航发展阶段,提出中国民航参与国家碳市场的框架性方案,重点对中国航空CO2排放总量控制目标设计及目标分解方案进行了论述,并从公平性和经济成本角度对所提方案进行分析。分析的结论是:方案不会在中国航空企业之间造成实质性竞争扭曲,不同情景下行业购买碳配额的成本每年增加1.7亿~14.3亿美元,若考虑中国民航至少60%的成本转嫁能力,方案不会对中国民航发展造成严重制约。  相似文献   
876.
碳交易政策的经济影响:以广东省为例   总被引:1,自引:0,他引:1  
通过构建广东省两区域动态模型,对广东省碳交易及其他政策措施进行定量评估,分析实施可调控总量的碳交易政策机制对广东省及参与交易部门的经济影响。研究结果表明,按照减排情景到2015年广东完成19.5%的碳强度下降目标,相比基准情景,GDP将减少0.7%;按照强减排情景到2015年将完成20.5%的碳强度下降目标,相比基准情景GDP将减少0.9%;如果在强减排情景的基础上实施碳交易政策,GDP相对基准情景减少0.8%,到2015年实施碳交易政策可减少GDP损失约90亿元,说明广东建立碳排放权交易机制能够发挥支持经济发展和节能减碳双赢的作用。  相似文献   
877.
Mucins are important components of mucus,which form a natural,physical,biochemical and semipermeable mucosal layer on the epidermis of fish gills,skin,and the gastrointestinal tract. As the first step towards characterizing the function of Muc2,we cloned a partial Megalobrama amblycephala Muc2 cDNA of 2 175 bp,and analyzed its tissue-specific expression pattern by quantitative real-time PCR(qPCR). The obtained sequence comprised 41 bp 5′-untranslated region(5′-UTR),2 134 bp open reading frame encoding a protein of 711 amino acids. BLAST searching and phylogenetic analysis showed that the predicted protein contained several common secreted mucin-module domains(VWD-C8-TIL-VWD-C8) and had high homology with mucins from other vertebrates. Among four candidate reference genes(β- Actin,RPI13α,RPII,18S) for the qPCR,R PII was chosen as an appropriate reference gene because of its lowest variation in different tissues. M. amblycephala Muc2 was mainly expressed in the intestine,in the order(highest to lowest) middle-intestine fore-intestine hind-intestine. Muc2 was expressed relatively poorly in other organs(brain,liver,kidney,spleen,skin and gill). Furthermore,after 20-days of starvation,M. amblycephala Muc2 expressions after refeeding for 0h,3 h,16 h,3 d,and 10 d were significantly decreased in the three intestinal segments(P 0.05) at 16 h,and were then upregulated to near the initial level at 10 d.  相似文献   
878.
Trophic structure of fish communities is fundamental for ecosystem-based fisheries management, and trophic spectrum classifies fishes by their positions in food web, which provides a simple summary on the trophic structure and ecosystem function. In this study, both fish biomass and abundance trophic spectra were constructed to study the spatial and seasonal variations in the trophic structure of demersal fish assemblages in Jiaozhou Bay, China. Data were collected from four seasonal bottom trawl surveys in Jiaozhou Bay from February to November in 2011. Trophic levels(TLs) of fishes were determined by nitrogen stable isotope analysis. This study indicated that most of these trophic spectra had a single peak at trophic level(TL) of 3.4–3.7, suggesting that demersal fish assemblages of Jiaozhou Bay were dominated by secondary consumers(eg. Pholis fangi and Amblychaeturichthys hexanema). The spatial and seasonal variations of trophic spectra of Jiaozhou Bay reflected the influence of fish reproduction, fishing pressure and migration of fishes. Two-way analysis of variance(ANOVA) showed that seasonal variations in trophic spectra in Jiaozhou Bay were significant(P 0.05), but variations among different areas were not significant( P 0.05). The trophic spectrum has been proved to be a useful tool to monitor the trophic structure of fish assemblages. This study highlighted the comprehensive application of fish biomass and abundance trophic spectra in the study on trophic structure of fish assemblages.  相似文献   
879.
880.
Numerous small-scaled, extensional faults occur densely in the mudstone layer of the Qingshankou 1st member (Qn1) in Songliao Basin. Its attribute and genetic mechanism are highly concerned but still controversy. The high-resolution 3D seismic datasets of a new block that covers most of the Sanzhao sag of Songliao Basin is studied., The characteristics of the profile and plane geometry of the extensional fracture system in the Sanzhao sag were depicted in detail through fine seismic interpretation using coherent technology. Based o the results, we proposed that: (1) The extensional fault system is mainly polygonal fault, which probably resulted from rupture pressure related to the episodic hydrocarbon-expulsion from the mudstone of Qn1. However, the tectonic inversion in Songliao Basin may also contribute to the formation and development of the polygonal fault system; (2) The polygonal faults were mainly formed by the end of deposition period of the Nenjiang Formation, and some experienced vertical direction propagation caused by the strong tectonic inversion at the end of deposition period of the Mingshui Formation; (3) The polygonal faults connect the Qn1 hydrocarbon source rock with the underlying Fuyang oil layer and the overlying Putaohua oil layer, and thus are important migration channels for the oil and gas accumulation; (4) Until the end of deposition period of the Nenjiang Formation, hydrocarbon generated in the Qn1 mainly migrated downward into the underlying Fuyang oil layer via the small polygonal faults rather than upwards to the Putaohua oil layer. On the contrary, by the end of deposition period of the Mingshui Formation, the oils from Qn1 source rock can migrate either downward into the Fuyang oil layer or upward into the Putaohua oil layer. It is noteworthy that the vertical propagation of the polygonal faults induced by the tectonic inversion might also damage the Fuyang accumulations formed earlier. ©, 2015, Science Press. All right reserved.  相似文献   
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