Occurrence of Persea Mill. from the Siwalik Forest of Darjeeling, Eastern Himalaya: Paleoclimatic an

来源 :Journal of Earth Science | 被引量 : 0次 | 上传用户:deqiangranran
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Fossil leaf remains of two new species of Persea Mill., belonging to the family Lauraceae collected from the lower part of the Siwalik sediments(Gish Clay Formation of Sevok Group, Middle Miocene) of Darjeeling foothills of eastern Himalaya, are described. The new species are Persea miogamblei sp. nov. and Persea neovillosa sp. nov.. On the basis of leaf architecture(size, shape and venation pattern) fossil leaves described in this article closely resemble modern leaves of Persea gamblei(King ex Hook. f.) Kosterm. and Persea villosa(Roxb.) Kosterm.. The geographic distribution of the fossils and their modern counterparts are discussed and on that basis tropical evergreen vegetation with a warm and humid climate at the time of deposition of the Siwalik sediments is suggested in contrast to the present day tropical deciduous vegetation in this area. The present finding also suggests probable migration of these lauraceous taxa to Southeast Asia. Fossil leaf remains of two new species of Persea Mill., Belonging to the family Lauraceae collected from the lower part of the Siwalik sediments (Gish Clay Formation of Sevok Group, Middle Miocene) of Darjeeling foothills of eastern Himalaya, are described. The new species are Persea miogamblei sp. nov. and Persea neovillosa sp. nov .. On the basis of leaf architecture (size, shape and venation pattern) fossil leaves described in this article Related Resemble modern leaves of Persea gamblei (King ex Hook. f.) Kosterm. And Persea villosa (Roxb.) Kosterm .. The geographic distribution of the fossils and their modern counterparts are discussed and on that basis tropical evergreen vegetation with a warm and humid climate at the time of deposition of the Siwalik sediments is suggested in contrast to the present day tropical deciduous vegetation in this area. The present finding also suggests probable migration of these lauraceous taxa to Southeast Asia.
其他文献
With the support of the National Natural Science Foundation of China,a research team led by Profs.Chen Jun(陈骏)and Teng Hui(滕辉)at the Key Laboratory of Surfi
目的:探讨丹参酮Ⅱ A(TanⅡA)对大鼠出血性休克-再灌注肾损伤的防治作用。方法:SD大鼠 30只,分TanⅡA高、中、低剂量组、PEG组和复苏24h组,每组6只。采用修改的Yu’s法制备本实验模型,观察腹腔注射TnⅡA后的肾组
病房对讲系统主机面板的改进及效果二院药学部贾梦艳肖铁树王晓光随着医院规模的扩大、管理制度的完善、医疗设施的齐全,我院循环、呼吸二病区为了更好地观察、了解患者的病情
1996年9月在阿根廷首都布宜诺斯艾利斯召开了一次题为《美洲的家庭医学和卫生改革》的会议。这次会议由WHO、WHO美洲办事处、泛美卫生局、国际家庭医学中心和世界家庭医师组
目的:评价益气健脾养阴方联合化疗治疗中晚期胃癌的疗效性及其安全性。方法:对已确诊的晚期胃癌43例随机分成两组,分别为治疗组和对照组比较疗效。结果:两组患者在体力状态疗
The growing track record of polarization in China has led to increasing concern about poverty reduction. From an institutional arrangement standpoint, how the p
幽门螺杆菌与消化性溃疡,胃炎的关系近乎多有报道,与胃癌可能也有关系[’]。扬中市为全国著名的上消化道恶性肿瘤高发区,居民胃病患病率亦较高。为了解当地居民幽门螺杆菌的感染情
<正>杨海军教授著《中国古代商业广告史》已于近日由河南大学出版社出版,近30万字。杨海军教授任职于河南大学新闻与传播学院,长期从事广告历史研究,写下诸多著作,学术积累丰
改革与革命是马克思主义唯物史观中的重要内容。社会革命是同整个社会制度的根本变化相联系的,是促进社会从低级形态向高级形态根本转变的社会活动。这种活动主要表现于:先进
土木工程·大射电望远镜反射面支承张拉结构非线性分析罗永峰 ,于庆祥 ,陆 燕 ,等 1 (1 )……………………………………………聚氨酯泡沫复合夹层板抗爆特性分析任志刚 ,楼