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Qiao Xiufu Yao Peiyi Wang Chengshu Tan Lin Zhu Shenyu Zhou Shengde Zhang Yuqing 《《地质学报》英文版》1991,4(3):217-235
Abstract The Middle Proterozoic Chartai Group separated by two unconformities consists of three depositional sequences: the Shujigou Formation-Zenglongchang Formation (DS I ), the Agulugou Formation (DS II ), and the Liuhongwan Formation (DSIU). The carbonate platform and back-platform basin are the basic environment model of the Chartai Group. The syndepositional faults on the oceanward side of the carbonate platform and large- scale slumping in the soft sediments are important marks of facies tracts. The newly established Zenglongchan uplifting, an epeirogenetic uplifting, plays an important role in the formation of the palaeogeographic framework of the Chartai Group. The stratigraphic correlation between the Chartai Group and the Bayan Obo Group is made for the first time by using sequence stratigraphic principie and model established by P.R. Vail. The Chartai Group, which was deposited on the northern passive continental margin of the North China platfom, represents the platform cover. 相似文献
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通过对中国沙区仍属植物标本整理、鉴定和文献考证,认为中国沙区有杨属(PopulusL.)植物17种、5变种和1变型;《中国沙漠植物志》记载的青甘小叶杨应由变种提升为种;额河杨、伊犁杨、光应银白杨、辽东小叶杨和菱叶小叶杨等2种、2变种和1变型《中国沙漠植物志》应予收录。 相似文献
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差不嘎蒿特性的初步研究 总被引:13,自引:6,他引:7
对差不嘎蒿(Artemisia halodendron)的叶片解剖结构、生物学和生态学特性的初步研究表明: 差不嘎蒿是一种叶肉质化的旱生植物。生长期长(4月底或5月初至9月上旬), 地上部分的生长分为生殖枝、上部营养枝和基部营养枝生长。根系非常发达, 以水平根系为主, 根系多分布于20-60cm土层内。它通过发达的根系吸收水分和保水力较强的叶片保持水分的能力抗旱来抵抗干旱的胁迫, 通过强大的根系来抵抗风蚀和萌发不定根来适应沙埋的环境, 是一种优良的先锋固沙植物。 相似文献
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沙坡头沙区锦鸡儿属植物抗旱性的研究 总被引:8,自引:1,他引:7
本文对沙坡头沙区的12种锦鸡儿属植物的叶片解剖结构和水分生理等特征进行了比较研究,利用主分量,综合分析了与抗旱性有关的各个特征,客观地列出该属一些植物种的抗旱性顺序:白皮锦鸡儿>刺叶锦鸡儿>垫状锦鸡儿>狭叶锦鸡儿>柠条锦鸡儿>甘蒙锦鸡儿>绢毛锦鸡儿>中间锦鸡儿>小叶锦鸡儿>荒漠锦鸡儿>川西锦鸡儿>树锦鸡儿。供选择适宜的固沙植物种提供参考。 相似文献
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徐州贾汪地区中—上寒武统藻礁,风暴层与海平面变化 总被引:5,自引:1,他引:4
笔者详细研究了徐州贾汪地区中-上寒武统的二郎山等剖面,将张夏组-凤山组划分为3个各具特色的三级层序,根据各层序内副层序的堆叠形式进一上划分出海侵体系域(TST)凝缩段(CS)及高位体系域(HST)其中张夏层序的藻礁为中-晚寒武世期间发育的最大规模碳酸盐岩缓坡藻礁,崮山层序凝胶缩代表中-晚寒武世最大海泛(海侵)期沉积,长山-凤山层序顶部白云岩代表中-晚寒武世最小海平面(海退)时期的沉积。 相似文献
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Seismic event, sequence and tectonic significance in Canglangpu Stage in Paleo-Tanlu Fault Zone 总被引:4,自引:0,他引:4
The Canglangpu Stage of Lower Cambrian Series is widely distributed along both sides of the Tanlu (Tancheng-Lujiang) Fault
Zone in the Jiao-Liao-Xu-Huai regions. In the Liaodong Peninsula, the Canglangpu Stage consists of three formations, i.e.
Gejiatun, Dalinzi and Jianchang formations in ascending order (lying on the eastern side of the Tanlu Fault Zone). The Dalinzi
Formation, developing in a littoral Sabkha environment, is full of catastrophic event records of violent seism, such as liquefied
muddy-sandy veins, hydroplastic folds, hydroplastic micro-faults (three forming an organic whole), liquefied crinkled deformations,
liquefied breccia and sandy dikes. Based on such records, the seismic liquified sequence of argillaceous rocks in Sabkha is
built up. In northern Jiangsu and Anhui provinces, however, there hardly observe seismic records in the Canglangpu Stage,
which consists of Jinshanzhai and lower Gouhou and upper Gouhou formations (lying on the western side of the Tanlu Fault Zone).
Even if the Gouhou Formation, developing in a lagoon-dry environment, is in the same climate zone as the Dalinzi Formation,
and 4 depositional sequences have been identified in the Canglangpu Stage in Northern Jiangsu and Anhui provinces, however,
in the same stage in the Liaodong Peninsula, there exist only 3 ones. Therefore, it is not supported by the above mentioned
evidence (such as catastrophic events, sequences stratigraphy and lithologic correlation of formations) that the Canglangpu
Stage in the Liaodong Peninsula came from northern Jiangsu and Anhui provinces through a long-distance, about hundreds kilometers,
left-hand displacement of the Tanlu Fault in the Mesozoic era. 相似文献
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山西云岗石窟侏罗系地震液化砂岩柱的发现及其大地构造意义 总被引:1,自引:0,他引:1
本文主要报道在华北克拉通北缘云岗石窟景区内侏罗系地层中发现的20余个由地震液化形成的砂岩柱。地震导致的砂土液化是非常普遍的自然现象,地震波的震动使埋藏在地下未固结的饱和砂质沉积物迅速变为流体并在巨大压力下喷涌至地表,形成砂火山或泥火山。2008年汶川8. 0级大地震和2012年新西兰6. 2级地震都产生了严重的液化现象,在对地表造成严重破坏的同时,分别在地表形成了一系列的溢出丘和形态完好的砂火山。古地震之后,液化砂质沉积物往往在上涌的通道内固结成岩,形成穿层的岩柱或岩管。近年来,美国科罗拉多大峡谷相继发现很多地震液化形成的中生代巨型碎屑岩柱。2018年,本文作者在云岗石窟景区内的侏罗系云岗组中发现了20多条直径15~20cm左右、高可达2m以上穿层“侵入”的砂岩柱,有的在纵向上呈串珠状排列,有的呈不规则的树枝状自下向上伸展,膨大狭缩、分支复合现象非常明显,砂岩柱内部结构均一,不见任何层理。砂岩柱顶端的泥质围岩石中有明显向上牵引、拖拽的痕迹。这些砂岩柱没有任何硅化木的特征,也不是普通成岩作用形成的结核,与暴雨、泥石流、重力滑塌等作用均无任何关系,是古地震液化作用在地层内保存的遗迹,故称为液化砂岩柱。地震液化砂岩柱发育的层位位于李振宏等人(2014)在宁武—静乐盆地侏罗系云岗组顶部的凝灰质泥晶碳酸盐层位(160 Ma)之下约40m处,初步判定形成这些液化砂岩柱的古地震发生于160. 75 Ma~160 Ma之间的晚侏罗世。古地震的形成过程与燕山运动引起的地壳运动有直接的关联,是华北克拉通内与燕山运动伴生的古地震在地层中留下的最直接证据。 相似文献
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