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The palynological assemblage from Wulaga dinosaur site in Jiayin from southeastern Zeya-Bureya Basin was studied. The high content of pteridophytes spores is characteristic for this assemblage. The further characters are in decrease of abundance-tricolpate pollen, Ginkgocycadophytus, pollen of Taxodiaceae, Cupressaceae and Taxaceae (TCT) , bisaccate pollen of Pinaceae, and triporate pollen. The bone-bearing burials of Wulaga dinosaur site formed under conditions of vast swampy river valley covered by ferns and taxodialeans. Tricolpate pollen, produced by plants, close to those of Platanaceae, Fagaceae, Betulaceae, and Juglandaceae, counts in favor of valley river open canopy forests. 相似文献
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宁波盆地地下揭示的一套包含暗色膏硝质泥岩、泥质白云岩在内的紫红、灰紫色泥岩、棕褐色砂砾岩、细砂岩和玻屑凝灰岩的地层,均称方岩组,内含膏盐并具油色显示。对其时代有早、晚白垩世和早第三纪之认识,笔者从70~90年代地质工作中所获化石分析认为,虽然宁波盆地这一层位含化石不丰,但从分布及数量上比较,相对占优势的应该是孢粉和植物化石,其时代意见也较为一致,指示为早白垩世。 相似文献
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孢粉浓度统计法在西北土类堆积物的应用 总被引:1,自引:0,他引:1
本文以宁夏水洞沟全新统剖面为例,运用孢粉浓度统计法对我国西北地区土类堆积物进行了初步研究,并与传统的孢粉百分比统计法所得结果进行了对比。文中,运用电子计算机进行了孢粉资料整理,划分出了七个孢粉组合带,基本上符合我国北方全新世气候变化的一般规律。结果表明,两种方法所反映的古植被、古气候变化趋势基本一致。在孢粉数量丰富的情况下,孢粉浓度统计在图式上表现得更突出和明显;在孢粉数量较少时,用百分比统计法更便于说明问题。 相似文献
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Stratigraphy of southeastern flanks of Raichikhinsk brown coal field (Zeya-Bureya sedimentary basin)
Tat'yanaV.Kezina 《东北亚地学研究》2004,7(2):110-119
The results of the palynologic and paleobotanic analyses have allowed determining the Paleocene (including Danian) and Eocene deposits in the series of coal-bearing sediments of southeastern flanks of the Raichikhinsk brown coal field. Their age was corroborated by the palynologic and paleobotanic data. The detailed biostartigraphic data were obtained in the area““ Pioneer““ for the first time. The coal-bearing strata were correlated with those from the sections of the Arkhara-Boguchan brown coal field and the stratotype of the Tsagajan Formation of the Bureya Belogor‘ye. 相似文献
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三个钻孔的岩心表明,南李庄泻湖沉积可分为5层,最大厚度15m左右。根据孢粉、微量元素以及岩相特点可将泻湖的演化分为5个阶段。资料表明,湖水变深时期是气候温湿时期,湖水变浅时期为气候凉干时期,指示泻湖的兴衰明显受气候控制。 相似文献
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广西百色盆地第三系孢粉化石极为丰富。根据大量孢粉分析鉴定资料,共建立7个孢粉组合及6个亚组合,其时代分别代表早第三纪中-晚始新世、晚始新世、渐新世以及晚第三纪上新世。 相似文献
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笔者近年从事河南二叠系山西组地质工作,分析鉴定孢粉化石1473个。计62个属,89个种,6个近似种,62个未定种,2个疑源类属。其中,三缝孢占59.4%,单缝孢占33.1%,花粉占4.7%,疑源类占2.8%。通过综合分析对比,笔者认为:山西组孢粉组合特征与国内、外同时代地层中的孢粉组合特征基本一致;孢粉的属、种变化与山西组所产动、植物化石有相关性,并进一步佐证了山西组煤层的成煤环境属滨海潮坪和三角洲分支流间湾环境。 相似文献
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冰后期长江河口段古河谷地层层序特征 总被引:2,自引:0,他引:2
末次盛冰期,由于基面大幅度下降,长江河口段形成了深切古河谷。河流携带的部分粗砂砾在河床上形成滞留沉积。冰后期海平面上升引发的海侵造成了长江古河谷的充填和河床相、河漫滩河口湾相和部分河口湾浅海相的形成。尔后的进积产生了部分河口湾浅海相及三角洲相。根据钻孔资料绘制的古河谷地质剖面图显示,冰后期海侵旋回出现在三角洲顶点到现在河口口门地区,溯河而上受海洋影响的程度逐渐减弱。古河谷的中部,靠近主泓线附近,沉积层序完整。古河谷的边缘地带,往往缺失底部的河床相砂砾层。底部的厚层河床相砂砾层是由河床滞留沉积和溯源加积堆积形成的,在古河谷沉积层序中存在着多种沉积间断。 相似文献
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本文通过钱塘江深切谷的论述对末次冰期深切谷的恢复主要依据下列证据进行:(1)谷底为侵蚀不整合面,为末次冰期海平面下降,河流侵蚀切割所致;(2)谷内为异常厚的河流沉积物所充填,是冰后期海平面上升时形成,其中河漫滩沉积年代约14000~7500a以前;(3)深切谷之上被海相地层覆盖。超浅层生物气田分布在深切谷内,当今河流及全新世晚期河口湾与末次冰期深切谷既有区别又有继承性,其流域是浅层生物气藏分布的有利地段。 相似文献
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Jinqing Liu Ping Yin Yong Zhang Hongying Song Shipu Bi Zhimin Cao Shanshan Liu 《中国海洋大学学报(英文版)》2017,16(5):747-756
Detrital minerals of 137 offshore and 22 river sediment samples collected from Qingdao coastal areas have been analyzed. Four mineral assemblage provinces can be classified by Q-mode cluster analysis. Factor analysis identifies two major factors that account for the total variability in most common minerals: 1) based on the relationship of quartz, hornblende, actinolite, micas, and authigenic pyrite, 41.55% of the variability is related to sediment sources; 2) based on the relationship of epidote, garnet, sphere, and ilmenite, 23.21% can be related to strong hydrodynamic conditions that control transport and sedimentation. By comparing mineral compositions of river waters in the study area, the following four mineral provenances can be identified. The Qingdao-Laoshan nearshore area has a quartz-feldspar-epidote-hornblende-limenite-limonite-sphene assemblage, which is largely attributed to relict sediment and coastal erosion. The Jimo-Haiyang nearshore area has a quartz-feldspar-hornblende-epidote-limonite-mica-actinolite assemblage, derived largely from the Wulong River and Rushan River, and is also affected by the Huanghe River, while the Qianliyan Island area in the deeper offshore area separated by a mud belt has a similar assemblage. The Haiyang-Rushan nearshore area has a quartz-feldspar-hornblende-epidote-micas-limonite assemblage, indicating multiple sources from the Rushan River, the Wulong River, the Huanghe River, and coastal erosion. The central area, located in an eddy center, has a mica-authigenic pyrite-hornblende-quartzfeldspar assemblage, indicating multiple sources dominated by Huanghe River distal sediments. 相似文献
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应用误差反向传播算法的人工神经网络,建立了流域年均含沙量的预测模型。该模型用于某流域年均含沙量预测的拟合率达90%以上,预留检验预报的准确率为75%。 相似文献
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A new dinosaur tracksite was discovered in a steeply inclined sandstone layer of the Middle Jurassic Sanjianfang Formation in the Shanshan area of the Turpan Basin. The site is the first record of dinosaur footprints from Xinjiang Province in northwestern China. More than 150 tridactyl theropod dinosaur footprints are preserved as positive hyporeliefs on the lower bedding plane of a fine-grained sandstone body. Most of the footprints are isolated and appear to be randomly distributed. Some show well defined phalangeal pads, heels and rarely indistinct impressions of the distal part of the metatarsus. Two distinct morphotypes are present: a larger type with relatively broad pads shows similarities to Changpeipus and Megalosauripus, and a slightly smaller, slender and gracile type which is similar to Grallator, Eubrontes and Anchisauripus. In both morphotypes, digit III is the longest with a length between 11.4 and 33.6 cm. A single imprint shows prominent scratches, probably formed during slipping of the track maker. 相似文献
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The first dinosaur tracksite from Xinjiang, NW China (Middle Jurassic Sanjianfang Formation, Turpan Basin) a preliminary report 总被引:1,自引:0,他引:1
A new dinosaur tracksite was discovered in a steeply inclined sandstone layer of the Middle Jurassic Sanjianfang Formation in the Shanshan area of the Turpan Basin. The site is the first record of dinosaur footprints from Xinjiang Province in northwestern China. More than 150 tridactyl theropod dinosaur footprints are preserved as positive hyporeliefs on the lower bedding plane of a fine-grained sandstone body. Most of the footprints are isolated and appear to be randomly distributed. Some show well defined phalangeal pads, heels and rarely indistinct impressions of the distal part of the metatarsus. Two distinct morphotypes are present: a larger type with relatively broad pads shows similarities to Changpeipus and Megalosauripus, and a slightly smaller, slender and gracile type which is similar to Grallator, Eubrontes and Anchisauripus. In both morphotypes, digit III is the longest with a length between 11.4 and 33.6 cm. A single imprint shows prominent scratches, probably formed during slipping of the track maker. 相似文献
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Extreme rainfall events and associated natural hazards in Alaknanda valley, Indian Himalayan region 总被引:2,自引:0,他引:2
JOSHI Varun KUMAR Kireet 《山地科学学报》2006,3(3):228-236
Introduction The Himalaya is considered to be the youngest mountains on the earth, and is tectonically very active, and hence inherently (geologically) vulnerable to hazards. Extreme rainfall events, landslides, debris flows, torrents and flash floods due… 相似文献