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Response of environmental sensitive grain size group in Core FJ04 from mud area in the north of East China Sea to East Asian winter monsoon evolvement
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作者 孙晓燕 李希彬 +1 位作者 岳晓峰 门翔 《Marine Science Bulletin》 CAS 2011年第2期1-12,共12页
AMS14C dating and grain-size analysis for Core FJ04, located at mud area in the North of East China Sea provide us a high-resolution grain-size distribution curve varying with depth and time. This paper got environmen... AMS14C dating and grain-size analysis for Core FJ04, located at mud area in the North of East China Sea provide us a high-resolution grain-size distribution curve varying with depth and time. This paper got environmental sensitive grain-size group by using standard deviation method, and proved that the selected sensitive grain-size group is an important proxy which can be used to reconstruct intensity of East Asian Winter Monsoon (EAWM). Then we got reconstruction of EAWM evolvement since 3 ka B.P., which revealed two main phases: (1) 3 - 1.15ka B.P., relative weak EAWM with middle frequency fluctuation; (2) 1.15 - 0ka B.P., really strong EAWM with high frequency fluctuation. And 1.15 ka B.P. is a distinct turning point. During the whole period, 11 intense events of EAWM were recorded and correlated well with other climate records, but the response extent was different, which showed consistency of climate change and particularity of region response. 展开更多
关键词 shelf of East China Sea mud area sensitive grain size group East AsianWinter Monsoon
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Burial fluxes and sources of organic carbon in sediments of the central Yellow Sea mud area over the past 200 years 被引量:4
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作者 YANG Shu YANG Qian +3 位作者 LIU Sai CAI Deling QU Keming SUN Yao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第10期13-22,共10页
Long-term changes of composition, sources and burial fluxes of TOC (total organic carbon) in sediments of the central Yellow Sea mud area and their possible affecting factors are discussed in this paper. Firstly, si... Long-term changes of composition, sources and burial fluxes of TOC (total organic carbon) in sediments of the central Yellow Sea mud area and their possible affecting factors are discussed in this paper. Firstly, similarity analysis is employed to confirm that the carbon burial features resulted from two collected cores are typical in the central Yellow Sea mud area where YSWC (Yellow Sea Warm Current) is prevalent. On this basis, the burial flux of TOC here was considered to be 235.5-488.4 pmol/(cm^2.a) since the first industrial revolution, accounting for about 70%-90% among burial fluxes of TC (total carbon) in the sediments. Compared TOC/TC ratio in the two cores with that in other marine sediments worldwide, we suggest that the growth of calcareous/non-calcareous organisms and dissolution of IC (inorganic carbon) are important factors controlling the TOC/TC ratio in sediment. Results of two-end mixed model based on fi13C data indicate that marine-derived organic carbon (OCa) is the main part among total burial organic carbon which accounts for a ratio over 85%. Due to the high TOC/TC ratio in the two cores, TC in the sediments also mainly exists as OCa, and the proportion of OCa is about 60%-80%. Away from the shore and relatively high primary production in upper waters are the main reasons that OCa is predominant among all burial OC in sediments of the central Yellow Sea mud area. Burial of OC in this mud area is probably mainly influenced by the human activities. Although the economic development during the late 19th century caused by the first industrial revolution in China did not obviously increase the TOC burial fluxes in the sediments, the rise of industry and agriculture after the founding of new China has clearly increased the TOC burial flux since 1950s. Otherwise, we also realize that among TC burial fluxes, TIC account for about 10%-30% in sediments of the central Yellow Sea mud area, so its burial could not be simply ignored here. Distinct from TOC burial, long-term TIC burial fluxes variations relate with climate changes more closely: the East Asian summer monsoon may influence the strength of the Huanghe River (Yellow River) flood, which could further affect the transport of terrestrial IC from land to the central Yellow Sea as well as the burial of these IC in the sediments. 展开更多
关键词 the central Yellow Sea mud area organic carbon burial flux source long-term changes human activities
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Environmental record from the mud area on the inner continental shelf of the East China Sea since the mid-Holocene 被引量:3
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作者 LIU Shengfa SHI Xuefa +2 位作者 LIU Yanguang WU Yonghua YANG Gang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2011年第4期43-52,共10页
Paleoclimate record was revealed in Core MZ01 covering the mid-Holocene in age,located in the mud area of the inner continental shelf of the East China Sea. The ancient environment featured low-energy shallow sea shel... Paleoclimate record was revealed in Core MZ01 covering the mid-Holocene in age,located in the mud area of the inner continental shelf of the East China Sea. The ancient environment featured low-energy shallow sea shelf deposition formed mainly by coastal currents. The results show that temporal variation in geochemistry corresponds with the climate changes inferred from historical record. Relatively low MgO/Al 2 O 3,CaO/K 2 O and high Al 2 O 3 /Na 2 O,K 2 O/Na 2 O,MnO/CaO values reflected a warm and humid climate in general,and vice versa. Therefore,these chemical indices could be applied to identify the variation of palaeoclimate in eastern China. The authors reconstructed the history of mid-Holocene climatic variation of the inner continental shelf of the East China Sea. From 8 300 a BP to 4 200 a BP,the climate was moderately warm and humid. From 4 200 a BP to 2 000 a BP,the climate turned cool and dry,and the regional climate frequently fluctuated in alternation of cool-dry periods(3 700 a BP,2 850 a BP and 2 400 a BP) and warm-wet periods(3 250 a BP and 2 650 a BP) . After 2 000 a BP,the climate of the study area gradually turned warm again,while the Little Ice Age,a cold event centered at around 250 a BP was indicated by those geochemical indices as mentioned above. 展开更多
关键词 HOLOCENE East China Sea mud area major element PALAEOCLIMATE East Asia monsoon
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High resolution records of flood deposition in the mud area off the Changjiang River mouth during the past century 被引量:3
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作者 胡刚 李安春 +3 位作者 刘健 徐刚 梅西 孔祥淮 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第4期909-920,共12页
This paper presents a paleoflood study to determine the flood frequency of the Changjiang River, based on core cj0702, taken from the Changjiang River subaqueous delta. We identified flood deposits by means of high-re... This paper presents a paleoflood study to determine the flood frequency of the Changjiang River, based on core cj0702, taken from the Changjiang River subaqueous delta. We identified flood deposits by means of high-resolution grain-size variation, sensitive population, geochemical indexes and magnetic susceptibility. The core covers a time span of 120 years by 21~pb dating and was sampled at 1-2 cm intervals. Grain size, geochemical elements, and physical parameters were analyzed. The results indicate that the sediment of the core is mainly composed of silt and clay, as well as groups of interbedded silt, clay silt, and clay. Vertically, the grain size pattern was controlled by seasonal variations in water discharge and by the sediment input in winter from the abandoned Huanghe River delta. River flooding caused extreme values in all our measured parameters. We identified more than 20 flood events that occurred since 1887 using the physical parameter analysis method. The environmentally sensitive component of sediment grain size (14.32-96.39 gm) contribution〉30%, Zr/Rb ratio〉l.5, and magnetic susceptibility〉16 were selected as the criteria for flood identification generally. We also found that floods that had taken place in the upstream, midstream, or downstream parts of the river were clearly identified by these indexes while the large-scale floods that covered the whole drainage area did not leave clear indications in the sediment record. This study for identification of flood events is of great significance for understanding hyperpycnal current sedimentation as well as for forecasting of floods. 展开更多
关键词 high resolution grain size flood deposition mud area the Changjiang River
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Provenance analysis of surface sediments in the Holocene mud area of the southern coastal waters off Shandong Peninsula,China 被引量:6
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作者 ZHANG Xiaobo BI Shipu +5 位作者 ZHANG Yong YANG Yuan LIU Shanshan KONG Xianghuai LI Xiaoyue CHU Hongxian 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第5期124-133,共10页
The sedimentary record of mud areas is an important carrier of information on the Holocene evolution of marine environments. Based on fine interpretations of the shallow stratigraphic section data, a small mud deposit... The sedimentary record of mud areas is an important carrier of information on the Holocene evolution of marine environments. Based on fine interpretations of the shallow stratigraphic section data, a small mud deposit area has been found in the southern coastal waters off Shandong Peninsula. This mud area is mainly distributed in coastal waters north of Laoshantou to the vicinity of Rushan Estuary. Overall, it is parallel to the coastline and spreads in a banded pattern, gradually thinning from offshore to the sea. The isopach map of depth distribution is parallel with the shoreline, and the depocenter lies in coastal waters of the Aoshan Bay where the maximum thickness is up to 22.5 m. Accelerator mass spectrometry(AMS) ^(14)C dating shows that the mud area was formed in the Holocene. The test data of surface sediments from the mud area, including particle size, mineral characteristics, and rare earth element contents, are used in comparisons with the composition of materials from the major surrounding medium and small rivers flowing into the sea and the Huanghe(Yellow) River. In this paper, the sedimentary characteristics and provenance of the mud deposit area are discussed. The results show that the formation of this mud area resulted from the joint action of the Huanghe River and surrounding rivers flowing into the sea. 展开更多
关键词 southern coastal waters off Shandong Peninsula mud area provenance analysis
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Grain size records reveal variability of the East Asian Winter Monsoon since the Middle Holocene in the Central Yellow Sea mud area,China 被引量:42
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作者 HU BangQi YANG ZuoSheng +3 位作者 ZHAO MeiXun Yoshiki SAITO FAN DeJiang WANG LiBo 《Science China Earth Sciences》 SCIE EI CAS 2012年第10期1656-1668,共13页
Three cores (ZY-1, ZY-2 and ZY-3) retrieved from the Central Yellow Sea mud (CYSM) were analyzed in sensitive grain size and AMS J4C dating to reconstruct the history of the East Asian Winter Monsoon (EAWM) sinc... Three cores (ZY-1, ZY-2 and ZY-3) retrieved from the Central Yellow Sea mud (CYSM) were analyzed in sensitive grain size and AMS J4C dating to reconstruct the history of the East Asian Winter Monsoon (EAWM) since the Middle Holocene in the study area. The results show that these data provide a continuous history of the EAWM over the past 7.2 ka and that the EAWM can be divided into three periods: strong and highly fluctuating during 7.2-4.2 ka BP; moderate and relatively stable during 4.2-1.8 ka BP; and weakened during 1.8-0 ka BP. Compared with the East Asian Summer Monsoon (EASM) recorded in the previous studies, the evolutionary history of the EAWM broadly follows the orbital-derived winter insolation with a similar long-term step-decreased trend as the EASM. At the centennial scale, however, the EAWM intensified events correlate well with the EASM weakened events and the North Atlantic climatic variations (Bond events 0 to 5) within the dating error, most likely forced by the reduction of solar irradiance through changes in the oceanic-atmospheric circulation patterns. 展开更多
关键词 East Asian Winter Monsoon Central Yellow Sea mud area sensitive grain size solar activity Middle Holocene
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Centurial Evolution of an Offshore Mud Deposition Area in the Changjiang (Yangtze) Estuary and Its Links to Environmental and Anthropogenic Activities
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作者 CONG Jingyi HU Gang +4 位作者 JONELL Tara N YUAN Zhongpeng KONG Xianghuai ZHANG Yong WANG Yonghong 《Journal of Ocean University of China》 SCIE CAS CSCD 2020年第4期790-800,共11页
Large amounts of sediments originating from the Changjiang(Yangtze)River are deposited in the subaqueous delta and in the adjacent muddy area off the mouth and on the inner shelf of the East China Sea.The terrestrial ... Large amounts of sediments originating from the Changjiang(Yangtze)River are deposited in the subaqueous delta and in the adjacent muddy area off the mouth and on the inner shelf of the East China Sea.The terrestrial sediments deposited in these areas not only contain information about the composition and environment of the source area,but they also record changes in anthropogenic activities.A sediment piston core(CJ0702)was extracted from the Changjiang subaqueous depocenter(31.00°N,122.67°E)in a water depth of 22.0 m.The core was subsampled at 1–2 cm intervals and analyzed for grain size,clay mineralogy,and major element geochemistry.Results indicate a relatively high sediment accumulation rate of approximately 3.11 cm yr−1.These parameters exhibited only minor cyclical fluctuations in the core,which resulted from many factors.During the past 120 years,the Changjiang River-derived sediment is the primary source of sediment in the offshore mud area without evidence for the Yellow River-derived sediment increasing.After the trunk stream shifted from the North Branch to South Branch,the variations of proxies are controlled by the periodic fluctuation possibly linked to El Niño-Southern Oscillation(ENSO)and the Pacific Decadal Oscillation(PDO).In addition,anthropogenic heavy metal concentrations can be divided into three stages,which coincide well with economic development and environmental protection policies. 展开更多
关键词 sedimentary evolution mud area Changjiang(Yangtze)Estuary sediment transport anthropogenic activity
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East Asia Winter Monsoon changes inferred from environmentally sensitive grain-size component records during the last 2300 years in mud area southwest off Cheju Island,ECS 被引量:28
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作者 Yoshiki Saito 《Science China Earth Sciences》 SCIE EI CAS 2006年第6期604-614,共11页
Environmentally sensitive grain-size component (ESGSC) extracted from grain-size data of a sediment core B2, which were retrieved from mud area southwest off Cheju Island (MACI), East China Sea (ECS), can be used to i... Environmentally sensitive grain-size component (ESGSC) extracted from grain-size data of a sediment core B2, which were retrieved from mud area southwest off Cheju Island (MACI), East China Sea (ECS), can be used to indicate the variations of East Asia Winter Monsoon (EAWM), with high (low) content/mean-size of ESGCS denote to strong (weak) EAWM. Combined with AMS14C datings core B2 provides a continuous high-resolution record of EAWM changes over the past 2300 years, with an average resolution of 13 years. The results show that the variations of EAWM are con-sistent with temperature changes inferred from historical documents in eastern China over the past 2300 years, from which four climate stages may be identified. In stages before 1900 aBP (50 AD) and 1450―780 aBP (50―1170 AD) the EAWM were comparatively weak, corresponding to warm climate periods in eastern China, respectively. And in stages of 1900―1450 aBP (50―500 AD) and 780―219 aBP (1170―1731 AD) the EAWM were strongly developed, which correspond well to climate changes of two cold periods in eastern China. It is also shown from this study that the stage at 780―219 aBP (1170―1731 AD) was the coldest climate period during the last 2300 years and could be, therefore, related to the Little Ice Age (LIA). Climatic fluctuations appeared obviously in all the four stages, and two climate events of abrupt changes from warm to cold occurred at around 1900 aBP (50 AD) and 780 aBP (1170 AD), of which the latter is probably related to globe-scale changes of atmospheric circulation at that time. 展开更多
关键词 EAST China Sea mud area environmentally SENSITIVE GRAIN-SIZE component EAST Asia Winter Monsoon Little Ice Age Late Holocene.
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Records of the East Asian winter monsoon from the mud area on the inner shelf of the East China Sea since the mid-Holocene 被引量:27
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作者 LIU ShengFa SHI XueFa +8 位作者 LIU YanGuang QIAO ShuQing YANG Gang FANG XiSheng WU YongHua LI ChaoXin LI XiaoYan ZHU AiMei GAO JingJing 《Chinese Science Bulletin》 SCIE EI CAS 2010年第21期2306-2314,共9页
AMS14C dating and analysis of grain size,major elements and clay minerals were applied to Core MZ01 from the mud area on the inner shelf of the East China Sea.Based on the environmentally sensitive grain size,clay min... AMS14C dating and analysis of grain size,major elements and clay minerals were applied to Core MZ01 from the mud area on the inner shelf of the East China Sea.Based on the environmentally sensitive grain size,clay mineral and major element assemblages,the history of the East Asia winter monsoon since the mid-Holocene could be reconstructed.These three proxies,mean grain size(>9.71μm),chemical index of alteration(CIA)and ratio of smectite to kaolinite in particular,show similar fluctuation patterns. Furthermore,10 extreme values corresponding to the contemporary cooling events could be recognized since the mid-Holocene;these extreme values are likely to have been caused by the strengthening of the East Asia winter monsoon.The cooling events correlated well with the results of theδ18O curves of the Dunde ice core and GISP2,which therefore revealed a regional response to global climate change.Four stages of the East Asia winter monsoon were identified,i.e.8300-6300 a BP,strong and unstable;6300-3800 a BP,strong but stable;3800-1400 a BP,weak and unstable;after 1400 a BP,weak but stable. 展开更多
关键词 东亚冬季风 中全新世 Sea 内陆架 中期 中国 亚洲 面积
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织纳地区龙潭组煤系页岩气储层特征与勘探潜力评价
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作者 王文强 何金先 曹文杰 《科学技术与工程》 北大核心 2024年第20期8409-8418,共10页
为查明织纳地区龙潭组页岩气勘探前景,通过分析Z2井龙潭组泥页岩样品的矿物组成、有机地化特征、微观孔隙特征、钻孔泥页岩厚度、分布情况及其含气性特征,研究龙潭组页岩气储层特征并对页岩气勘探潜力进行评价。结果表明:泥页岩有机质... 为查明织纳地区龙潭组页岩气勘探前景,通过分析Z2井龙潭组泥页岩样品的矿物组成、有机地化特征、微观孔隙特征、钻孔泥页岩厚度、分布情况及其含气性特征,研究龙潭组页岩气储层特征并对页岩气勘探潜力进行评价。结果表明:泥页岩有机质类型为Ⅱ_(2)-Ⅲ型,且以Ⅱ_(2)为主,总有机碳含量为1.34%~8.25%,平均值为3.68%,有机质成熟度为0.92%~3.24%,平均值为2.45%,属于高-过高成熟演化阶段,具有较好的生气潜力。扫描电镜结果显示泥页岩样品主要发育四类微观孔隙,包括粒内孔、粒间孔、有机质孔和微裂隙,内部孔隙发育,为页岩气提供良好的储集空间。Z2井泥页岩脆性矿物含量为24.40%~63.08%,平均值为41.22%,泥页岩总厚度为170.74 m,占比42%,发育5个有效连续厚度大于15 m的泥页岩层,与邻井可形成2个泥页岩层段,适宜进行压裂改造。织纳地区龙潭组泥页岩具备良好的生气条件、储集条件和可压裂性,具有较大勘探潜力。 展开更多
关键词 织纳地区 龙潭组 泥页岩 页岩气 储层特征
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北黄海西部泥质区全新世以来沉积有机碳埋藏特征 被引量:1
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作者 王培杰 胡利民 +5 位作者 闫天浩 王厚杰 毕乃双 王楠 张洋 吴晓 《海洋地质与第四纪地质》 CAS CSCD 北大核心 2024年第2期110-119,共10页
北黄海西部泥质区沉积环境稳定、沉积记录连续,是重建过去周边流域变化与黄海海洋环境信息的良好载体。目前围绕北黄海西部泥质区沉积有机碳的研究工作多局限于通过表层沉积物揭示其现代分布特征,对于该泥质区长时间尺度沉积有机碳埋藏... 北黄海西部泥质区沉积环境稳定、沉积记录连续,是重建过去周边流域变化与黄海海洋环境信息的良好载体。目前围绕北黄海西部泥质区沉积有机碳的研究工作多局限于通过表层沉积物揭示其现代分布特征,对于该泥质区长时间尺度沉积有机碳埋藏过程与机制的研究相对薄弱。通过北黄海西部泥质区W03岩芯的总有机碳指标,重建了全新世以来北黄海西部沉积有机碳的埋藏特征,探讨了气候及海洋环境变化对北黄海西部沉积有机碳埋藏的控制机制。研究表明:海平面上升的停滞期(10.3~9.8 cal.kaBP),发育硬质黏土层,有机碳以陆源输入为主(60.7%),动荡的沉积环境导致总有机碳含量相对较低,平均含量仅为0.22%;海平面上升期(9.8~7.0 cal.kaBP),海源有机碳的贡献增加(47.7%),相对稳定的沉积环境有利于该时期有机碳的埋藏;高海平面以来(7.0 cal.kaBP至今),黄海环流体系逐渐形成,陆源有机碳输入随着东亚冬季风驱动的沿岸流强度变化发生相应的改变,海源有机碳的贡献继续增加(50.0%),总有机碳的含量升高至0.58%。北黄海西部泥质区全新世以来沉积有机碳埋藏主要受控于海平面变化和海洋环流体系的运动。 展开更多
关键词 泥质区 全新世 沉积有机碳 北黄海
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南黄海SYS90-1A孔第四纪沉积物磁性地层学研究
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作者 陆凯 孙军 +7 位作者 李广雪 杨慧良 王忠蕾 梅西 陈晓辉 祁江豪 朱晓青 强小科 《海洋地质与第四纪地质》 CAS CSCD 北大核心 2024年第2期97-109,共13页
可靠的年代地层框架是开展南黄海地区第四纪环境演变研究的基础。目前南黄海南部地区缺乏可靠年代学控制的长序列钻孔。通过对南黄海南部SYS90-1A孔(孔深90.1 m)沉积物开展详细的磁性地层学研究,并结合AMS14C测年结果及区域已有磁性地... 可靠的年代地层框架是开展南黄海地区第四纪环境演变研究的基础。目前南黄海南部地区缺乏可靠年代学控制的长序列钻孔。通过对南黄海南部SYS90-1A孔(孔深90.1 m)沉积物开展详细的磁性地层学研究,并结合AMS14C测年结果及区域已有磁性地层学结果,建立南黄海南部地区第四纪沉积物年代地层框架。结果显示,SYS90-1A孔岩芯记录了从布容(Brunhes)正极性时至松山(Matuyama)负极性时上部,包括Kamikatsura和Santa Rosa地磁漂移事件。早、中更新世界线即布容正极性时与松山负极性时界线(B/M界线)深度位于74.2 m,Kamikatsura和Santa Rosa地磁漂移事件深度分别位于79.75~82.47 m和85.25~87.74 m。根据Kamikatsura和Santa Rosa地磁漂移事件的年代控制点和平均沉积速率,推算钻孔底部年龄为0.96 Ma。南黄海SYS90-1A孔早更新世晚期的沉积速率约为8.66 cm/ka,中更新世以来的沉积速率约为9.5 cm/ka,而全新世以来的沉积速率为12.8 cm/ka,沉积速率自早更新世晚期以来呈增加趋势。这一结果不仅为南黄海南部第四纪沉积物研究提供了有效的年代学约束,而且为南黄海地区第四纪地层划分和对比、沉积环境与气候变化、物源示踪等研究提供了重要的时间标尺。 展开更多
关键词 古地磁学 沉积速率 第四纪 中部泥质区 南黄海
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Upwelling and anthropogenic forcing on phytoplankton productivity and community structure changes in the Zhejiang coastal area over the last 100 years 被引量:7
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作者 DUAN Shanshan XING Lei +3 位作者 ZHANG Hailong FENG Xuwen YANG Haili ZHAO Meixun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第10期1-9,共9页
Phytoplankton productivity and community structure in marginal seas have been altered significantly during the past three decades, but it is still a challenge to distinguish the forcing mechanisms between climate chan... Phytoplankton productivity and community structure in marginal seas have been altered significantly during the past three decades, but it is still a challenge to distinguish the forcing mechanisms between climate change and anthropogenic activities. High time-resolution biomarker records of two 210Pb-dated sediment cores(#34: 28.5°N, 122.272°E; CJ12-1269: 28.861 9°N, 122.515 3°E) from the Min-Zhe coastal mud area were compared to reveal changes of phytoplankton productivity and community structure over the past 100 years. Phytoplankton productivity started to increase gradually from the 1970 s and increased rapidly after the late 1990 s at Site #34; and it started to increase gradually from the middle 1960 s and increased rapidly after the late 1980 s at Site CJ12-1269. Productivity of Core CJ12-1269 was higher than that of Core #34. Phytoplankton community structure variations displayed opposite patterns in the two cores. The decreasing D/B(dinosterol/brassicasterol) ratio of Core #34 since the 1960 s revealed increased diatom contribution to total productivity. In contrast, the increasing D/B ratio of Core CJ12-1269 since the 1950 s indicated increased dinoflagellate contribution to total productivity. Both the productivity increase and the increased dinoflagellate contribution in Core CJ12-1269 since the 1950–1960s were mainly caused by anthropogenic activities, as the location was closer to the Changjiang River Estuary with higher nutrient concentration and decreasing Si/N ratios. However, increased diatom contribution in Core #34 is proposed to be caused by increased coastal upwelling, with higher nutrient concentration and higher Si/N ratios. 展开更多
关键词 biomarkers phytoplankton community structure Min-Zhe coastal mud area Changjiang Diluted Water UPWELLING
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河南矿区高灰细泥煤泥水的絮凝沉降试验研究
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作者 鲁忠良 王擘昊 +3 位作者 于跃先 史长亮 何俊 王婕 《河南理工大学学报(自然科学版)》 CAS 北大核心 2024年第1期35-41,共7页
目的随着采煤机械化程度的提高和重介质选煤工艺普及,入选浮煤泥中高灰细泥的含量逐渐增加。高灰细泥是影响煤泥水沉降效率的最直接因素,对煤泥水中的高灰细泥进行处理,直接关系着煤炭资源生产和水资源利用。针对河南矿区煤泥水具有高... 目的随着采煤机械化程度的提高和重介质选煤工艺普及,入选浮煤泥中高灰细泥的含量逐渐增加。高灰细泥是影响煤泥水沉降效率的最直接因素,对煤泥水中的高灰细泥进行处理,直接关系着煤炭资源生产和水资源利用。针对河南矿区煤泥水具有高灰细泥的特性,方法通过设计正交试验测试不同种类的絮凝剂和搅拌速度对煤泥水的沉降率的影响及其之间的相互作用的效果,提高煤泥水沉降效率。结果结果表明:六偏磷酸钠与聚丙烯酰胺的分散性能及絮凝性能更优,搅拌速度、六偏磷酸钠用量、聚丙烯酰胺用量对高灰细泥煤泥水沉降率的影响程度依次减小,搅拌速度和聚丙烯酰胺用量之间的相互关系对沉降率影响最为显著;当六偏磷酸钠用量40.08 mg/L、聚丙烯酰胺用量5.75 mg/L、搅拌速度411.12 r/min,沉降率可达95.5%,沉降率提高的原因在于高灰细泥絮凝过程中絮团成球明显,絮凝剂的桥接作用可以使分散颗粒聚团并发展为球形,长条不规则颗粒明显减少,颗粒群粒形的改变有助于煤泥水的沉降,在一定搅拌速度下粒形保持较为规整,可增加沉降概率,使煤泥水得以有效沉降。结论通过改善煤泥水中颗粒的粒度粒形特性,可以有效提高河南矿区高灰细泥煤泥水的沉降效率。研究结果可为处理高灰细泥煤泥水提供理论支持和实践参考。 展开更多
关键词 河南矿区 煤泥水 高灰细泥 沉降率 粒形
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雄安新区基岩热储钻探施工技术探讨 被引量:1
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作者 齐恭 李杨 +2 位作者 齐晓凤 高鹏举 董向宇 《钻探工程》 2024年第1期126-130,共5页
针对雄安新区基岩热储钻探中风化壳钻进、地层大量漏失封堵及基岩取心的钻探工程难点,通过对所处牛驼镇地热田、容城地热田和高阳地热田地热地质状况、岩性特点的分析,提出了基岩热储地热钻探有效解决方案,包括采用小径探孔施工工法、... 针对雄安新区基岩热储钻探中风化壳钻进、地层大量漏失封堵及基岩取心的钻探工程难点,通过对所处牛驼镇地热田、容城地热田和高阳地热田地热地质状况、岩性特点的分析,提出了基岩热储地热钻探有效解决方案,包括采用小径探孔施工工法、采用封隔器有效完成水泥浆堵漏、借鉴金刚石满眼取心钻具技术等。 展开更多
关键词 基岩热储 地热钻探 风化壳 漏失地层 泥浆 封隔器 取心 雄安新区
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鄂尔多斯盆地杭锦旗地区井漏地质机理分析
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作者 韩涛 李功强 +2 位作者 白彬艳 高小淇 骆淼 《工程地球物理学报》 2024年第2期247-255,共9页
鄂尔多斯盆地北部杭锦旗地区钻井过程中频繁出现井漏现象,为了研究搞清楚井漏产生的地质机理,采用杭锦旗地区的钻井、录井、测井等资料,开展了研究区井漏高发层位、区域、漏失特征等因素的分析。分析研究结果表明:研究区井漏区域主要位... 鄂尔多斯盆地北部杭锦旗地区钻井过程中频繁出现井漏现象,为了研究搞清楚井漏产生的地质机理,采用杭锦旗地区的钻井、录井、测井等资料,开展了研究区井漏高发层位、区域、漏失特征等因素的分析。分析研究结果表明:研究区井漏区域主要位于刘家沟组泥岩、下石盒子组储层以及元古界顶部风化壳,漏失机理主要为刘家沟组泥岩本身易破碎,承压能力差,漏失层位主要受断层、褶皱以及风化壳产生的裂缝控制;下石盒子组储层受断层影响,发育高角度裂缝;元古界顶部风化壳附近裂缝发育。基于井漏发生的地质机理提出了以下几种预警方法:井漏大数据分析法、复杂构造识别法、储层改造分析法,对于预防井漏有积极作用。 展开更多
关键词 杭锦旗地区 井漏特征 地质机理 预警方法
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岩溶区排泥库泥浆泄漏应急处置管理经验探讨
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作者 陈哲 骆巍 《中国矿业》 北大核心 2024年第9期73-79,共7页
岩溶区排泥库具有尾矿粒度细和地质条件复杂两大特点,致使近年来泥浆泄漏事故频发。泥浆通过岩溶通道外泄至周边水系,污染下游河道、水塘、泉眼等,对库区周边生态环境及居民生产、生活造成极坏的负面影响和极大的经济损失。如何有效应... 岩溶区排泥库具有尾矿粒度细和地质条件复杂两大特点,致使近年来泥浆泄漏事故频发。泥浆通过岩溶通道外泄至周边水系,污染下游河道、水塘、泉眼等,对库区周边生态环境及居民生产、生活造成极坏的负面影响和极大的经济损失。如何有效应对甚至避免该类事故,成为工程技术人员、厂矿企业及地方政府密切关心的问题,也给排泥库设计、建设及管理人员提出极大的挑战。针对排泥库的泄漏特点和应急处置难点,系统分析排泥库从选址、设计、施工至运行全寿命周期过程中所应关注的重点,包括地质勘察、岩溶治理、应急管理体系、泄漏点处置及应急池建设等。结合近年来排泥库建设、管理过程中总结、积累的相关经验,同时借鉴行业专家针对尾矿库突发事件的应急处置经验,提出了排泥库泄漏应急处置管理应具备的全新理念。并通过工程案例,明确排泥库泥浆泄漏应急处置管理的重点、难点,以及具体实践过程中可参考的思路和方法,对提高排泥库应急处置管理水平和化解泥浆泄漏风险具有较大的现实意义。 展开更多
关键词 岩溶区 排泥库 泥浆泄漏 应急处置管理 全寿命周期 应急池
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全新世以来南黄海中部泥质区沉积物的源汇过程及其控制因素
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作者 谷玉 常鑫 +3 位作者 孔凡兴 兰凯 庄光超 刘喜停 《海洋地质与第四纪地质》 CAS CSCD 北大核心 2024年第5期140-150,共11页
南黄海中部泥质区沉积了大量来自邻近河流的陆源沉积物,是研究沉积物物源的良好区域,但其沉积物的输运过程和控制因素尚不明确。本文利用南黄海中部泥质区岩芯YSCW-1中沉积物的粒度和元素组成特征,查明自全新世以来研究区沉积物的源汇... 南黄海中部泥质区沉积了大量来自邻近河流的陆源沉积物,是研究沉积物物源的良好区域,但其沉积物的输运过程和控制因素尚不明确。本文利用南黄海中部泥质区岩芯YSCW-1中沉积物的粒度和元素组成特征,查明自全新世以来研究区沉积物的源汇过程及其控制因素。基于^(14)C放射年龄,YSCW-1岩芯沉积物为9.3 ka以来的沉积,泥质沉积中心形成于约6.5 ka。粒度组成表明研究区沉积物主要由砂、粉砂和黏土组成。基于地球化学相关指标,研究区沉积物来源受到黄河和长江的影响。6.7 ka以前,黄河沉积物占据主导地位;6.7 ka之后长江对南黄海中部泥质区的贡献量增加,可能与黄海现代环流体系的形成有关,海洋锋面限制了黄河以及朝鲜河流沉积物向南黄海中部泥质区的输送。 展开更多
关键词 粒度 元素地球化学 物源 南黄海中部泥质区
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基于CEL算法的神狐海域泥火山内部物质运动过程数值模拟
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作者 刘晓艳 孙永福 +3 位作者 宋玉鹏 修宗祥 李西双 宋丙辉 《海洋科学进展》 CAS CSCD 北大核心 2024年第2期325-336,共12页
以南海北部神狐海域地震剖面识别的泥火山为基础,基于耦合的欧拉-拉格朗日算法(CEL)模拟了泥火山内部物质的运动过程。通过不同阶段的对比分析,研究探讨了泥火山的形成机理,总结了泥火山内部物质的运动特征及规律。数值模型的结果显示... 以南海北部神狐海域地震剖面识别的泥火山为基础,基于耦合的欧拉-拉格朗日算法(CEL)模拟了泥火山内部物质的运动过程。通过不同阶段的对比分析,研究探讨了泥火山的形成机理,总结了泥火山内部物质的运动特征及规律。数值模型的结果显示泥火山形成过程中物质的运移具有明显的阶段性变化,展现了物质在运移时的应力与应变的不规则变化规律,本文根据这些变化分析了泥火山形成过程中应力、应变与能量的强度变化趋势。地层在物质向上刺穿过程中受力分布表现出明显的不均匀性,中间部位的突起破裂引起两侧地层的隆升。由模拟结果提供的泥火山形成过程中内部物质的特征,可以推动对泥火山形成机制及过程的进一步认识,同时也能对深部底辟构造以及油气迁移提供理论指导。 展开更多
关键词 神狐海域 泥火山 CEL算法 刺穿
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矿区生活污水处理过程中多相泥膜耦合生物技术应用
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作者 贾海琴 《山西化工》 CAS 2024年第2期216-217,223,共3页
集生物膜法和其它污水处理法于一体的生物膜耦合工艺在矿区生活污水处理中取得广泛应用。为探讨生物膜耦合工艺的应用效果,进行现场试验与分析。结果表明,应用多相泥膜耦合生物技术处理矿区生活污水后,COD、氮污染物、总磷的去除率均较... 集生物膜法和其它污水处理法于一体的生物膜耦合工艺在矿区生活污水处理中取得广泛应用。为探讨生物膜耦合工艺的应用效果,进行现场试验与分析。结果表明,应用多相泥膜耦合生物技术处理矿区生活污水后,COD、氮污染物、总磷的去除率均较高,出水水质达到地表水Ⅳ类标准,多相泥膜耦合生物技术能够取得良好的污水处理效果。 展开更多
关键词 矿区生活污水 多相泥膜耦合生物技术 试验分析 脱氮除磷
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