Soil-geomorphology relationships in Sirjan playa, south central Iran     

M.H. Farpoor  M. NeyestaniM.K. Eghbal  I. Esfandiarpour Borujeni 《Geomorphology》2012,138(1):223-230

To study the soil-geomorphology relationships and the effect of past and present climate on soil formation, 10 representative pedons on different landforms, including rock pediment, mantled pediment, piedmont plain, playa margin and playa, were studied. Non-saline clay flat, saline clay flat with and without puffy grounds, wet zone, and salt crust were among the geomorphic surfaces observed in Sirjan playa. Soil moisture varies from mesic (on rock and mantled pediments) to aridic regimes (on piedmont plain, playa margins, playa and mantled pediment). Soil temperature regime in the area is mesic except on playa surfaces and mantled pediment which are thermic. Results of the study showed that soil salinity increased from the rock pediment to playa surfaces. The maximum EC of 314 dS/m was observed in the puffy ground clay flat. Kaolinite, illite, smectite, chlorite and palygorskite clay minerals were identified using XRD analysis. Coatings and infillings of CaCO₃ were observed in pediment and gypsum lenticels and interlocked plates were found on piedmont plain and playa. Clay coatings and infillings in the piedmont plain suggest the presence of a more humid paleoclimate in the history of the area.  相似文献   

Micromorphological evidences of climatic change in Yazd region, Iran   总被引：1，自引：0，他引：1  

Ruhollah Taghizadeh Mehrjardi  Shahla Mahmoodi  Ahmad Heidari  Ali Akbarzadeh 《山地科学学报》2009,6(2):162-172

The fact of, present is the key of the past, will help us to use paleosols properties as indicators of the ecological characteristics of past .time, particularly the paleoclimate. In this respect the micro- morphological properties showed to be a very good indicator. Therefore, for investigating of climate change in Ardakan-Yazd plain, Central Iran 9 pedons were digged and described. Yazd has an arid climate with less than 100 mm annual precipitation and more than 22℃ mean annual temperature （Aridic-hyper thermic soil moisture and temperature regions, respectively）. Based on the morphological and physicochemical analysis Arglic, Calcic and Gypsic diagnostic horizons have been distinguished in these soils. Thin section studied showed that the illuviated form of clay includes, infillings on channel, coating on pendant, on nodules and on grains, at lower depths and also juxtaposed calcite needles on void argillan at upper part of the profiles. Mineralogical result showed fine clay in arglic horizon, too. Considering depth and forms of these pedofeatures, we concluded that, the observed illuviated clays at lower depth must be the result of the more humid climate of the past, where the carbonates have been removed completely as pendant, nodules or coating to considerable depth, following processes, clay has been dispersed and also trans located to these depths. In contrast to these features, the juxtaposed needle calcite at the shallower depth is probably the result of drier climate of today.  相似文献   

福建明溪寒塘组地质特征及时代归属   总被引：4，自引：1，他引：4  

胡宗良  陈兴高  冯宗帜 《福建地质》2001,20(2):70-77

福建明溪北部寒塘地区出露一套低绿片岩相浅变质岩系，原划分为中-上元古界下峰（岩）组。经1：5万区调和剖面研究，现已查明其空间层位在万全（岩）群之上，并伏于盖洋群之下，其岩石组合，原岩建造与其上覆及下伏岩石地层差异明显，具自身特点，厚度较大，且区内有一定延伸性，因此，作者新创建寒塘组，据其与上覆，下伏地层关系及及取得的930Ma单颗粒锆石U－Pb同位素年龄资料，将其时代归属青白口纪，该岩石地层单位的的建立及其时代确定，对闽西北前寒武纪变质岩地层划分，区域对比及构造研究具有重要意义。  相似文献   

在静力触探应用中有关土层分类命名问题的探讨   总被引：1，自引：0，他引：1  

曹圣华  杨晓东雷霄 王彦 《江苏地质》2004,28(1):31-35

多年来，静力触探的土层分类命名一直是困扰勘察设计人员的大问题，以静力触探资料整理中的普通经验及铁道部《静力触探技术规则》(TB37-93)中有关土类划分内容，结合勘察实践做些讨论，指出“普遍经验”的局限与相关规范的优缺点，并尝试提出新的工作方法和见解。  相似文献   

New data on the Lower Bajocian (Middle Jurassic) ammonite genus Mollistephanus Buckman, 1922 from southern England     

Robert Baron Chandler 《Proceedings of the Geologists' Association. Geologists' Association》2004,115(3):221-234

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定福庄地热试验井成井工艺研究     

左明星  王佟  曾铁军 《中国煤田地质》2006,18(6):52-54

JR-121井位于北京市定福庄南里,开采蓟县系雾迷山组1600m以深热储层的岩溶裂隙水。该试验井施工使用GZ-2000型水源钻机,TBW-850/50型泥浆泵,钻探深度2202.98m。成井过程中,根据不同层段,采用不同成井工艺,在目的含水层的上覆非取水层段,采用分级下套管及水泥封闭的方法进行止水,泥浆与回旋方法钻进;在取水段,采用裸眼孔底钻铤加压、泥浆护壁与回旋钻进。洗井工艺上,采用酸化、液态CO2和空压机引喷相结合的联合洗井方法。使用此成井工艺,止水效果良好,达到了开发岩溶裂隙地热水的目的。  相似文献   

Spatial variability of metals in the inter-tidal sediments of the Medway Estuary,Kent, UK   总被引：7，自引：0，他引：7  

Spencer KL 《Marine pollution bulletin》2002,44(9):933-944

Concentrations of major and trace metals were determined in eight sediment cores collected from the inter-tidal zone of the Medway Estuary, Kent, UK. Metal associations and potential sources have been investigated using principal component analysis. These data provide the first detailed geochemical survey of recent sediments in the Medway Estuary. Metal concentrations in surface sediments lie in the mid to lower range for UK estuarine sediments indicating that the Medway receives low but appreciable contaminant inputs. Vertical metal distributions reveal variable redox zonation across the estuary and historically elevated anthropogenic inputs. Peak concentrations of Cu, Pb and Zn can be traced laterally across the estuary and their positions indicate periods of past erosion and/or non-deposition. However, low rates of sediment accumulation do not allow these sub surface maxima to be used as accurate geochemical marker horizons. The salt marshes and inter-tidal mud flats in the Medway Estuary are experiencing erosion, however the erosion of historically contaminated sediments is unlikely to re-release significant amounts of heavy metals to the estuarine system.  相似文献   

瓦市气田化探异常特征及与油气埋深的关系     

宋玉光  贾国相 《矿产与地质》1998,12(2):131-136

瓦市气田是个多产储层的气田,从上至下有香溪群香三段、嘉陵江组、阳新统三个气层段。该气田油气储存具有深部多浅部少,而中间微的分布特点;构造以深部发育,而浅部不发育为特征;化探异常特征是周边弱而中间强。依据油气储存与构造和化探异常三者关系,剖析了烃类异常与油气埋藏深度的内在联系,认为该区环带晕异常是浅层气藏分布范围的响应,长条状异常则反映深部气藏的主要富集地段。  相似文献   

二连盆地找铀沉积层位的地震勘探研究     

徐贵来  梅汝吾 《铀矿地质》1997,13(4):226-231

本文通过对二连盆地努和廷矿床地震地质条件分析，采用了３种震源在矿床及其外围作地震干扰波调查，提出了工作区特征的低速多次波干扰的解决办法和探测１００ｍ以上的野外工作方案，并在ＳＰⅠ和ＳＰⅡ两条试验剖面测量中得到满意的验证。研究成果已在生产单位中得到应用。  相似文献   

紫色土系统分类研究     

唐时嘉  徐建忠  张建辉  罗有芳 《山地学报》1996,(Z1)

以参考文献[1]为指南,研究和鉴比了川鄂湘赣浙滇等省约70个紫色土剖面的属性特征,进行了紫色土系统分类和从土纲至亚类的连续命名.结果是,它们分别归属新成土纲中的紫色正常新成土和雏形土纲中的紫色湿润雏形土等2个土类、9个亚类.最后就土纲、亚纲、土类、亚类进行了检索.  相似文献