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1.
遗迹化石研究对于沉积环境分析具有重要意义。以加拿大麦凯Ⅲ油砂区块下白垩统McMurray组为研究对象,利用高分辨率岩心照片和全岩心CT扫描资料,在确认研究目的层遗迹化石发育属种、单体规模、组合类型及指相特征的基础上,分析了主力油砂层的沉积环境。结果表明: 目的层发育遗迹化石10属12种,包括Asterosoma isp.,Chondrites isp.,Diplocraterion isp.,Ophiomorpha nodosa,Palaeophycus tubularis,Planolites beverleyensis,Planolites isp.,Rosselia isp.,Skolithos verticalis,Skolithos isp.,Teichichnus isp.,Thalassinoides isp.;根据遗迹化石产状与围岩沉积特征,建立了Ophiomorpha-Skolithos、Asterosoma-Chondrites-Rosselia和Teichichnus-Rosselia￣Thalassinoides共3种遗迹组合,分别代表潮间带、潮下带以及浅海陆棚沉积环境中的遗迹化石组成特征。研究区油砂层优质储油砂体为潮间带沉积产物,潮汐砂坝、潮成砂脊为沥青的主要储集体。本研究既体现了全岩心CT资料在遗迹化石研究中的应用,也为潮坪沉积环境分析提供了有益参考。 相似文献
2.
遗迹化石研究对于沉积环境分析具有重要意义。以加拿大麦凯Ⅲ油砂区块下白垩统Mc Murray组为研究对象,利用高分辨率岩心照片和全岩心CT扫描资料,在确认研究目的层遗迹化石发育属种、单体规模、组合类型及指相特征的基础上,分析了主力油砂层的沉积环境。结果表明:目的层发育遗迹化石10属12种,包括Asterosoma isp.,Chondrites isp.,Diplocraterion isp.,Ophiomorpha nodosa,Palaeophycus tubularis,Planolites beverleyensis,Planolites isp.,Rosselia isp.,Skolithos verticalis,Skolithos isp.,Teichichnus isp.,Thalassinoides isp.;根据遗迹化石产状与围岩沉积特征,建立了Ophiomorpha-Skolithos、Asterosoma-Chondrites-Rosselia和Teichichnus-Rosselia-Thalassinoides共3种遗迹组合,分别代表潮间带、潮下带以及浅海陆棚沉积环境中的遗迹化石组成特征。研究区油砂层优质储油砂体为潮间带沉积产物,潮汐砂坝、潮成砂脊为沥青的主要储集体。本研究既体现了全岩心CT资料在遗迹化石研究中的应用,也为潮坪沉积环境分析提供了有益参考。 相似文献
3.
通过对钻井岩心的观察和遗迹化石的鉴定,在东濮凹陷古近纪沙河街组沙三段发现遗迹化石10属15种,包括:Skolithos vertivalis,Skolithos linearis,Skolithos isp.,Palaeophycus tubularis,Palaeophycus isp.,Planolites montanus,Planolites beverlegensis,Planolites isp.,Mermoides isp.,Taenidium isp.,Teichichnus isp.,Helminthoidichnites tenuis,Helminthopsis isp.,Beaconites isp.和Thalassinoides isp.。根据岩性特征、沉积构造和遗迹化石的组成、分布特征,研究区沙三段主要发育正常三角洲前缘亚相、前三角洲亚相,并划分了反映不同沉积环境和水体深度的2种遗迹组合,分别为Palaeophycus-Planolites遗迹组合和Planolites-Helminthoidichnites遗迹组合。 相似文献
4.
《地质通报》2017,(Z1)
通过对塔里木盆地柯坪露头志留系依木干他乌组中遗迹化石的研究,鉴别出6属7种。化石分子有Chondrites isp.,Gordia.isp.,Helminthopsis aff.abeli,Ophiomorpha nodosa,Planolites beverleyensis,Planolites montanus,Thalassinoides isp.。这些遗迹化石具有较高的分异度和较低的丰度。按古生态或造迹生物的行为习性分类,可分为3种生态类型:(1)居住迹(Domichnia),Ophiomorpha nodosa,Thalassinoides isp.;(2)进食迹(Fodinichnia),Planolites beverleyensis,Planolites montanus,Chondrites isp.;(3)觅食迹(Repichnia),Gordia isp.,Helminthopsis aff.abeli。根据遗迹化石的古生态特征、沉积序列上的分布特点及围岩和沉积构造特征,依木干他乌组的遗迹化石可归为Planolites-Chondrites遗迹组合,属于Cruziana遗迹相,形成于泥坪沉积环境。 相似文献
5.
豫西济源地区早三叠世和尚沟组湖相遗迹化石及遗迹组构 总被引：2，自引：0，他引：2
豫西济源地区早三叠世和尚沟组滨浅湖沉积中动物遗迹化石共鉴定出9个遗迹属10个遗迹种。包括Arenicolites isp., Beaconites coronus, Cylindricum isp., Palaeophycus heberti, Palaeophycus tubularis, Planolites isp., Psilonichnus isp., Scoyenia gracilis, Skolithos linearis和Taenidium barretti等。根据遗迹化石分布特征及沉积环境分析,可识别出三种遗迹组构1）Scoyenia遗迹组构,反映了干旱气候条件下的滨湖沉积环境;2）Planolites—Taenidium遗迹组构,属于湖泊水体逐渐变浅的浅湖沉积环境;3）Psilonichnus遗迹组构,代表了水动力由弱到强的湖泊三角洲沉积环境。 相似文献
6.
Ichnofabrics and their Sedimentary Environment of the Lower Permian Taiyuan Formation, Western Henan 总被引：1，自引：0，他引：1
豫西下二叠统太原组中发育丰富的遗迹化石,常见有Zoophycos,Taenidium,Thalassinoides,Teichichnus,Gordia,Nereites,Chondrites和Planolites等,部分灰岩层中还发育生物扰动构造.根据遗迹化石的形态、组成、产状、分布特征以及丰度、分异度、生物扰动程度的不同,在研究区太原组碳酸盐岩中共识别出5种遗迹组构,包括类型A——Gordia-Planolites遗迹组构、类型B—— Rhizocoralliurn- Thalassinoides遗迹组构、类型C—— Zoophycos- Taenidium遗迹组构、类型D——Zoophycos- Speckle burrow强生物扰动遗迹组构、类型E——Chondrites- Nereites遗迹组构.其中类型C根据Zoophycos在剖面上所展现的各种特征,又可细分为3种类型,即类型C-1,C-2和C-3.通过分析宿主岩的沉积特征,表明太原组碳酸盐岩中的遗迹组构主要分布于潟湖潮坪和台内浅滩(类型A)、正常天气浪基面之上的浅海上部或局限台地(类型B,类型C-1和类型C-2)、正常天气浪基面之下的开阔台地(类型C-3,类型D)和风暴浪基面之下的浅海下部或水动力条件类似的较闭塞的沉积环境中(类型E). 相似文献
7.
晋东南陵川地区上石炭统—下二叠统太原组灰岩中遗迹化石发育,已识别出10个遗迹属14个遗迹种,常见遗迹化石包括Zoophycos,Helminthopsis,Planolites,Nereites,Chondrites,Thalassinoides,Rhizocorallium,Ophiomorpha,Palaeophycus和Teichichnus等,其中Zoophycos最为发育。依据遗迹化石的组成、分布及产状特征,可建立4个遗迹组合:(1)Zoophycos-Thalassinoides遗迹组合;(2)Planolites-Helminthopsis遗迹组合;(3)Zoophycos-Teichichnus遗迹组合;(4)Nereites-Chondrites遗迹组合。对这些遗迹化石宿主岩石沉积特征的分析表明,太原组灰岩中的遗迹组合分别产生于海湾—潟湖环境(遗迹组合1)、浅海上部(遗迹组合2)、浅海中部(遗迹组合3)和浅海下部(遗迹组合4)。基于遗迹组合特征和沉积特征的综合分析,提出了研究区太原组遗迹化石组合的沉积环境模式,这一成果可为今后该区太原组中煤与煤层气生成的古环境研究提供生物学信息和基础理论资料。 相似文献
8.
黔东北印江合水和石阡乌谷溪的小溪组中发育良好的遗迹化石,经鉴定共计有5个属的遗迹化石:Palaeophycus isp.,Rusophycus isp.,Planolites isp.,Gordia isp.和Phycodes isp.。根据遗迹化石的组合特征,该组合属于Cruziana遗迹相。结合2个剖面的沉积构造和砂岩粒度分析结果,认为小溪组的沉积环境为相对安静的平均低潮线以下的临滨带。 相似文献
9.
豫西地区下二叠统太原组遗迹组构及其沉积环境 总被引：1，自引：0，他引：1
豫西下二叠统太原组中发育丰富的遗迹化石,常见有Zoophycos,Taenidium,Thalassinoides,Teichichnus,Gordia,Nereites,Chondrites和Planolites等,部分灰岩层中还发育生物扰动构造。根据遗迹化石的形态、组成、产状、分布特征以及丰度、分异度、生物扰动程度的不同,在研究区太原组碳酸盐岩中共识别出5种遗迹组构,包括类型A--Gordia-Planolites遗迹组构、类型B--Rhizocorallium-Thalassinoides遗迹组构、类型C--Zoophycos-Taenidium遗迹组构、类型D--Zoophycos-Speckle burrow强生物扰动遗迹组构、类型E--Chondrites-Nereites遗迹组构。其中类型C根据Zoophycos在剖面上所展现的各种特征,又可细分为3种类型,即类型C-1,C-2和C-3。通过分析宿主岩的沉积特征,表明太原组碳酸盐岩中的遗迹组构主要分布于潟湖潮坪和台内浅滩(类型A)、正常天气浪基面之上的浅海上部或局限台地(类型B,类型C-1和类型C-2)、正常天气浪基面之下的开阔台地(类型C-3,类型D)和风暴浪基面之下的浅海下部或水动力条件类似的较闭塞的沉积环境中(类型E)。 相似文献
10.
通过对豫西—晋中南地区上石炭统—下二叠统太原组碳酸盐岩中遗迹化石的组成、产状及分布特征的研究,结合部分生物潜穴中Sr含量、Sr/Ba值、1000×(Sr/Ca)值和δ13C值,得到不同地区太原组沉积期古水深的变化曲线,建立了3种不同水深的遗迹组合:(1) Nereites-Chondrites遗迹组合,产生于氧化还原界面附近水体相对较深的浅海下部环境;(2) Zoophycos-Teichichnus遗迹组合,形成于浪基面至氧化还原界面之间的浅海中部沉积环境;(3) Zoophycos-Thalassinoides遗迹组合,出现在平均海平面至浪基面之间的浅海上部或较为闭塞的海湾潟湖沉积环境。依据这3种遗迹组合在各剖面上的变化特征和古水深,认为在豫西—晋中南地区太原组沉积期发生过2次较大规模的海侵。这一成果为精细研究华北西部地区太原期沉积环境演变规律及对比地层提供了生物遗迹学方面的依据。 相似文献
11.
CSAMT 法在辽西康杖子区深部探矿中的应用 总被引：5，自引：0，他引：5
可控源音频大地电磁法(CSAMT)具有探测深度大、横向分辨率高、抗干扰能力强的特点,在深部找矿勘探中有着重要的指导意义。肖家营子铜钼矿床是辽西地区一个大型矽卡岩型金属矿床,大部分矿体是隐伏矿体,矿区外围的康杖子区与本区有相似的成矿地质环境,成矿地质条件优越.矿体与围岩电性差异明显,通过应用CSAMT,矿体具有低电阻特点,根据成果推断解释,对深部有利成矿部位进行了钻探验证,取得了理想的探矿效果,在矿区外围取得第二深度空间找矿重大突破。 相似文献
12.
Trends in landslide occurrence in Nepal 总被引：2，自引：0，他引：2
David N. Petley Gareth J. Hearn Andrew Hart Nicholas J. Rosser Stuart A. Dunning Katie Oven Wishart A. Mitchell 《Natural Hazards》2007,43(1):23-44
Nepal is a mountainous, less developed kingdom that straddles the boundary between the Indian and Himalayan tectonic plates.
In Nepal, landslides represent a major constraint on development, causing high levels of economic loss and substantial numbers
of fatalities each year. There is a general consensus that the impacts of landslides in countries such as Nepal are increasing
with time, but until now there has been little or no quantitative data to support this view, or to explain the causes of the
increases. In this paper, a database of landslide fatalities in Nepal has been compiled and analysed for the period 1978–2005.
The database suggests that there is a high level of variability in the occurrence of landslides from year to year, but that
the overall trend is upward. Analyses of the trends in the data suggest that there is a cyclicity in the occurrence of landslide
fatalities that strongly mirrors the cyclicity observed in the SW (summer) monsoon in South Asia. Perhaps surprisingly the
relationship is inverse, but this is explained through an inverse relationship between monsoon strength and the amount of
precipitation in the Hill District areas of Nepal. It is also clear that in recent years the number of fatalities has increased
dramatically over and above the effects of the monsoon cycle. Three explanations are explored for this: land-use change, the
effects of the ongoing civil war in Nepal, and road building. It is concluded that a major component of the generally upward
trend in landslide impact probably results from the rural road-building programme, and its attendant changes to physical and
natural systems. 相似文献
13.
Julie Okpala 《GeoJournal》1990,20(1):37-43
This paper traces the development of geographic education in Nigeria and examines the views of geographers, other academics,
students and the public at large about the importance of geography. Geography's value is immense despite the non-professional
nature of the discipline. Nevertheless, there is a need to define geography's status and ensure career prospects for students.
The Nigerian Geographical Association (from classroom teaachers to top geographers) must promote geography, improve its status
in schools and universities, and continuously restructure its content and methods to address pertinent social needs. 相似文献
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16.
Takeshi Nose Dr. 《GeoJournal》1985,10(3):261-276
Conclusions During the last ten years, aquaculture, especially mariculture has undergone remarkable expansion to counter-balance the gap between the supply and demand of fishery products in Japan. Its expansion has also been supported by the traditional preference of the Japanese people for seafood. Mariculture is now being forced to change its structure due to adverse economic circumstances such as the rise in the cost of energy, feeds and other materials for culture, low market prices, deterioration of environmental conditions, and many other factors. Before these constraints can be resolved, advanced scientific knowledge and technologies must be integrated to develop new types of aquaculture. Expansion of maricultural activities to more open-sea and off shore areas would be one route to follow. Technologies for the development of formulated diets not only for young but also for adults and larvae, establishment of feeding standards, prevention of epizootic diseases must support the establishment of modern aquaculture.The culture-based fisheries, or marine ranching, is becoming a subject for further development in Japan. Much research work has been conducted with a great degree of governmental support. Establishment of a net work of seedstock production farms has made it possible to carry out releasing experiments on a large scale. A newly integrated restoration system could be developed on the basis of these experiments, even though the profits resulting from the artificial restoration of stocks is not thouroughly verified at present. The commencement of a national scheme for culture-based fisheries would be a manifestation of the enthusiasm of the Japanese fish industry. 相似文献
17.
2010年,美国铀矿总共施工7 209个钻孔,总进尺1 493 520 m;生产铀1 628.55 t;铀矿业总支出费用为2.773亿美元,其中铀矿地勘费支出为3 450万美元,占铀矿业总费用的12.44%。铀矿地勘钻探费用为4 460万美元,占铀矿业总费用的16.08%。 相似文献
18.
硫代砷是富硫化物地下水中砷的重要形态,对环境和人类健康有潜在威胁。目前硫代砷研究程度尚低,本次主要针对国内外地下水（地热水）中硫代砷的存在形态,水文—生物—环境地球化学过程,样品保存,定量检测方法等方面进行研究。结论如下:pH, 氧化还原电位,硫化物含量和微生物作用等是影响地下水中硫代砷稳定存在和形态分布的重要因素。含铁矿物能与水中的硫代砷形成配位键对其进行吸附,吸附性普遍弱于（亚）砷酸盐,因此,地下水中硫代砷可能表现出更强的迁移性。用于硫代砷检测的自然水样在采集中可采取过滤,速冻,厌氧和低温短期保存的操作流程,以减缓该形态的转化甚至消失。色谱联用ICP-MS系统可用于自然水样中硫代砷的分离定量检测,紫外—可见分光光度法和X射线吸收光谱法在不同场景下也可对硫代砷进行定量和表征分析。地热水和浅层地下水中均可能存在硫代砷,由于水样中硫代砷的不稳定性,室内检测和分析难以准确反映现场过程,因此,野外样品保存技术和现场检测方法的更新可能在未来有更大研究空间,值得进一步探索。 相似文献
19.
内蒙古苏尼特地下水氟污染形成机理研究 总被引：4，自引：1，他引：3
为了研究内蒙古苏尼特地区地下水氟污染机理,本文运用水文地球化学分类方法,从水文地质、水化学特征两方面研究其地下水的水质特征、氟的起源、分布规律及污染形成机理。研究结果发现:高氟地下水的主要水质类型为HCO3—Na型,pH值在7.08～9.38之间,氟浓度与井深有关,即井越浅,氟浓度越高;地下水中氟浓度最高达14.78mg/L,5～9月地下水氟浓度相对增长率在7.8～23.1之间;F-浓度与Li+、Br-相关系数达0.89和0.82,受断层影响的深层地下水中F-浓度几乎与Li+、Br-没有相关关系,这暗示着氟来源于浅部,并受到强烈的蒸发作用影响而使水中的氟浓缩;地质调查发现该地区还有数个萤石矿存在,显微镜分析结果证实表层土壤中普遍存在CaF2,地下水中的氟来自CaF2。高氟地下水存在于潜水层,深部含水层的地下水可供开采。从断层带涌出的水对潜水层有稀释作用。 相似文献
20.
Radon is a radioactive gas emanating naturally from uranium rich granites and shales. It may be emitted from the ground surface into the atmosphere as a gas, or it may be dissolved into stream water and transported over distance. The levels of radon gas in soils at ground surface depend on a number of factors relating to the source of the gas and to its transmission. Igneous rocks contain the highest mean concentrations of radium and uranium. The depth of cover is relevant also. Surveys over the years by the National Radiological Protection Board (NRPB) and others have indicated that the highest concentrations in the United Kingdom occur in Cornwall, Devon and northeast Scotland. However, recent reports have indicated that high concentrations of the gas may be detected in small pockets in counties outside of those considered at high risk. This survey relates to a series of measurements taken in and around Darlington, County Durham. The results showed the presence of small areas with strong concentrations of radon in soil gas, but only minor levels of dissolved gas in stream waters. 相似文献