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1.
天山和阿尔泰山冰碛物显微结构特征   总被引:3,自引:0,他引:3  
采用薄片法对新疆阿尔泰山哈纳斯河流域和天山乌鲁木齐河源区冰上融出碛、冰下融出碛和滞碛的显微结构特征进行了分析。冰上融出碛的显微结构的主要特征是:次棱角状和破裂状表面特征、点支撑和边支撑结构、异向组构、不规则大孔隙;冰下融出碛显微结构的主要特征是:次棱角状和次圆状以及碎裂表面特征、点支撑和边支撑以及镶嵌和悬浮结构、微旋转和微叶理以及粉沙团块构造、定向组构、规则的圆孔隙和扁孔隙;滞碛显微结构的主要特征是:次棱角状和次圆状以及碎裂状表面特征、悬浮结构和镶嵌结构、微旋转和微叶理以及粉沙团块构造、定向组构、规则圆孔隙。不同冰碛显微特征的成因与冰川冰和冰碛产生的静压力、冰川的运动和冰碛介质以及由此引起的冰下磨蚀、压碎、剪切等过程有关。  相似文献   

2.
神农架大九湖地区更新世冰川遗迹的初步研究   总被引:3,自引:0,他引:3  
作者通过两次实地调查,发现神农架大九湖地区更新世冰川遗迹有冰斗、槽谷、基岩鼓丘和侧碛等。冰碛砾石砾向组构分析表明砾石a轴走向大多与所在谷地走向平行,倾角18~23°;砾石ab面倾向离散,倾角15—20°。冰碛细粒部分79.1—84.5%由粉砂和砂组成,粒度频率曲线呈双峰态。冰碛石英砂表面电镜扫描成象表明砂粒表面具有典型冰川砂的特征.根据冰川地貌特征和室内分析结果,本文把该地区晚更新世气候期划分为两次冰期和一次冰缘期。  相似文献   

3.
疏勒南山岗纳楼5号冰川现代冰碛物的沉积组构特征   总被引:2,自引:0,他引:2  
本文通过对疏勒南山岗纳楼冰碛物的沉积组构分析,提出了现代冰碛物的主要组构特征。水碛物成分组合简单,粒度分选作用极差。分选系数在5.14以上,平均园度约为20%。大多数冰碛石的长轴平行于其沉积时期冰川流动的方向。a轴指向N75°-89°W——S75°-89°E倾角0°-25°。沉积组构分析的方法是说明冰川沉积作用、冰成沉积物形成机理的一种有用的工具。此外,现代冰碛物的组构特征,对于研究古冰碛和冰碛岩也有着重要的意义。  相似文献   

4.
滇西北玉龙山第四纪冰川作用的探讨   总被引:5,自引:1,他引:5  
本文摘要地描述了玉龙山第四纪冰川作用所形成的地貌,如冰斗、刃脊、角峰、槽谷等冰蚀地貌和侧碛堤、终碛堤、冰碛丘陵等冰碛地貌;较详细地论述了玉龙山冰川沉积物的组构、粒度和石英砂粒表面的形态特征等,最后对冰期作了划分。  相似文献   

5.
以野外地质调查资料及岩石薄片为基础,通过研究贺兰山苏峪口正目观组冰碛砾岩的各种形态特征,依据冰川沉积学、沉积岩石学及古地理学等对苏峪口冰碛砾岩的形成环境进行分析.研究得出:该套冰碛砾岩是冰川搬运大小不等的岩块至苏峪口进行堆积,接着是海侵阶段,致使冰块周围水体温度升高,携带于冰块内的岩块、岩屑由于冰块的消融坠沉到海底还未固结的砂泥纹层上,并逐渐为碳酸盐泥晶掩埋形成.  相似文献   

6.
表文以“七1”冰川流域冰碛石和冰水砾石的组构测量为依据,对沉积物的组构特征及其与沉积环境的关系作了比较全面地讨论,冰碛石粒度频率曲线呈多峰式,粒度分选作用极差,σ_1>2,SK_1>0或<0,Kg<0.72,大多数冰碛石的长轴平行于冰流方向,冰水砾石呈双峰式,分选作用中等,δ_1=1.4-2, SK_1>0, Kg=0.92-1.14,大多数a轴平行于河流流向;C轴指向下游;ab面逆流倾斜,平均倾角30°左右,作者指出,冰碛石和冰水砾石的组构特征,对于研究沉积环境和鉴定古冰川、冰水沉积的成因类型有着重要的意义。  相似文献   

7.
祁连山中段新冰期以来的冰川序列及环境变化   总被引:2,自引:0,他引:2  
通过对七一冰川及其附近冰碛垅形态、植被覆盖、岩石种类及Schmidt hammer反弹R值、剖面内部组成的观测、对比和分析,认为新冰期时冰川扩张到海拔4 km处,较现代冰川末端降低约300 m,冰川前进约2 km左右.小冰期的三列冰碛垅形成时间间隔基本相同,规模依次减小,表明小冰期的三次冷期中以15世纪最冷,持续时间最长,而17世纪次之,19世纪持续时间最短.  相似文献   

8.
祁连山东段冷龙岭南麓白水河冰碛物ESR测年研究   总被引:12,自引:1,他引:11  
白水河是祁连山东段冷龙岭南麓大通河的一条支流,在其谷口保存有形态较完整的冰川终碛,终碛剖面中有将该终碛垄分成两次冰川作用的一推积垄,此次用ESR测年技术对采自该剖面中的冰碛物进行了测年研究,推积垄前部上样品测得的ESR年龄为73.0ka,55.8ka;推积垄后部靠近推积垄的一个样品,测得ESR年龄为36.7ka,所测得的ESR年龄与终碛垄沉积的新老关系相一致,经过ESR测年结果的误差与其可靠性讨论并结合终碛垄沉积关系和推积垄前后的^14C年龄得出;推积垄前部的冰碛物为末次冰期早期沉积的,与深海氧同位素的4阶段相对应;推积垄后部的冰碛物为末次冰期晚期所沉积的,可与深海氧同位素的2阶段相对应,此结论也进一步验证以往学者所得出的结论,说明冰碛物可以用ESR技术进行测年。  相似文献   

9.
以西藏东南部第四纪冰川形成的环境条件和现场调查获得的有关冰川活动的证据,分析了西藏巴河冲久地带垄状堆积物系冰川终碛堤堆积,巴松湖为冰碛物堵塞的湖泊,为西藏冲久-雪卡水电站的工程地质评价提供了地质证据.  相似文献   

10.
对AHM模型2种基于IRT的判别方法——方法 A和方法 B进行改良,得到方法 C和方法 D.通过蒙特卡洛模拟试验考察A、B、C、D等4种方法的诊断性能.结果表明:蒙特卡洛模拟试验的结果与理论研究结果相符,方法 C优于方法 A,方法 D优于方法 B,且从总体上看新方法的评价指标比对应原方法的评价指标有较大幅度的提高.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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