There are many outcrops of the Tertiary sediments in northeast India and a large number of plant megafossils have been described from there. Among all, the Late Oligocene sedimentary basin of Makum Coalfield is very i...There are many outcrops of the Tertiary sediments in northeast India and a large number of plant megafossils have been described from there. Among all, the Late Oligocene sedimentary basin of Makum Coalfield is very important because there is no other exposure having such a rich palaeofloral assemblage not only from northeast India but also from the whole country. The assemblage is also important to confirm whether the suturing between the Indian and Eurasian plates was complete to facilitate plant migration or not. All the reported plant fossils clearly indicate the prevalence of tropical climate in the region during the deposition of the sediments. As the majority of taxa occur in tropical evergreen to moist deciduous and littoral and swampy forest, a warm and humid climate may be envisaged in Upper Assam during the Late Oligocene. The abundance of palms and pantropical megathermal plant families in the Makum Coalfield indicate that the cold month mean temperature(CMMT) was not less than 18°C. The quantitative palaeoclimate reconstruction indicates a monsoonal climate during the period with the same intensity as that of the modern day. The absence of Southeast Eurasian elements in the fossil assemblage provides clear evidence that suturing between the Indian and Asian plates was not complete till the Late Oligocene. Several modern analogues of the fossil taxa are now endemic to the Western Ghats which lies in the same palaeolatitude.展开更多
A Neogene biota was found from the yellowish green or dark gray clay of the Daotaiqiao Formation in gold placer mines in Sifangtai Village,Huanan County,Heilongjiang Province,NE China in the 1990s.The age was determin...A Neogene biota was found from the yellowish green or dark gray clay of the Daotaiqiao Formation in gold placer mines in Sifangtai Village,Huanan County,Heilongjiang Province,NE China in the 1990s.The age was determined biostratigraphically to be late Middle Miocene to Late Miocene(most possibly Late Miocene) by vertebrate fossils and floral (including palynological) assemblage analyses.The Miocene age(showing drastic global climate展开更多
The Cenozoic flora of western India(Rajasthan and Gujarat) is adversely affected by the tectonic activity such as collision of the Indian subcontinent with the Eurasian plate which is responsible for the Himalayan and...The Cenozoic flora of western India(Rajasthan and Gujarat) is adversely affected by the tectonic activity such as collision of the Indian subcontinent with the Eurasian plate which is responsible for the Himalayan and Tibetan Plateau uplift. This collision and its resultants affected the ubiquitous tropical lowland vegetation of the Indian subcontinent(including western India) and are responsible for different types of topographic regions as seen today in the Indian subcontinent. The region is important as it has witnessed a drastic change in climate of the region since the Cenozoic time and also provided opportunities to the western and eastern flora to intermingle. The main basins in western India comprising Cenozoic sequences are: Bikaner-Nagaur, Jaisalmer and Barmer in Rajasthan and Kachchh, Mainland and Saurashtra in Gujarat. These basins are very rich in lignite which is the main source of electric power generation in western India. This lignite is mainly of Eocene in age. The Cenozoic flora of western India was almost tropical growing in well drained areas as compared to arid to sub-humid regions with xeric vegetation today. The reported fossils are represented by leaves, woods, fruits and seeds. The leaves are abundant in the Palaeogene as compared to the Neogene. The Neogene period can be marked by the abundant legumes and dipterocarpaceous remains. The important families viz., Anacardiaceae, Annonaceae, Arecaceae, Calophyllaceae, Clusiaceae, Combretaceae, Euphorbiaceae, Flacourtiaceae, Icacinaceae, Lauraceae, Lythraceae, Meliaceae, Moraceae, Myrtaceae, Pandanaceae and Sonneratiaceae have been reported from the Palaeogene sediments, whereas Anacardiaceae, Araucariaceae, Arecaceae, Combretaceae, Dipterocarpaceae, Fabaceae, Lauraceae, Lecythidaceae, Lythraceae, Malvaceae, Meliaceae, Moraceae, Podocarpaceae, Rhamnaceae, Rhizophoraceae, Rutaceae, Sapindaceae and Sonneratiaceae are known from the Neogene sediments. All the recovered elements strongly indicate the presence of much better climatic conditions in展开更多
记录2001—2010年间根据中国中、新生代植物大化石建立的新属25个(新生代的2个,中生代的23个),记录每一属的特征、模式种、地理分布及地质时代。对模式种的创建者、创建年代、所在文献的页码、图版、产地层位、标本保存状态、分类位置...记录2001—2010年间根据中国中、新生代植物大化石建立的新属25个(新生代的2个,中生代的23个),记录每一属的特征、模式种、地理分布及地质时代。对模式种的创建者、创建年代、所在文献的页码、图版、产地层位、标本保存状态、分类位置以及模式标本保存单位等作详细记录。另有一属(Tharrisia Zhou,Wu and Zhang)模式种的模式标本虽非产自中国,但该属是根据研究中国发现的材料修订含义笼统老属而从中区分出来的,所以也作了记录。展开更多
文摘There are many outcrops of the Tertiary sediments in northeast India and a large number of plant megafossils have been described from there. Among all, the Late Oligocene sedimentary basin of Makum Coalfield is very important because there is no other exposure having such a rich palaeofloral assemblage not only from northeast India but also from the whole country. The assemblage is also important to confirm whether the suturing between the Indian and Eurasian plates was complete to facilitate plant migration or not. All the reported plant fossils clearly indicate the prevalence of tropical climate in the region during the deposition of the sediments. As the majority of taxa occur in tropical evergreen to moist deciduous and littoral and swampy forest, a warm and humid climate may be envisaged in Upper Assam during the Late Oligocene. The abundance of palms and pantropical megathermal plant families in the Makum Coalfield indicate that the cold month mean temperature(CMMT) was not less than 18°C. The quantitative palaeoclimate reconstruction indicates a monsoonal climate during the period with the same intensity as that of the modern day. The absence of Southeast Eurasian elements in the fossil assemblage provides clear evidence that suturing between the Indian and Asian plates was not complete till the Late Oligocene. Several modern analogues of the fossil taxa are now endemic to the Western Ghats which lies in the same palaeolatitude.
文摘A Neogene biota was found from the yellowish green or dark gray clay of the Daotaiqiao Formation in gold placer mines in Sifangtai Village,Huanan County,Heilongjiang Province,NE China in the 1990s.The age was determined biostratigraphically to be late Middle Miocene to Late Miocene(most possibly Late Miocene) by vertebrate fossils and floral (including palynological) assemblage analyses.The Miocene age(showing drastic global climate
文摘The Cenozoic flora of western India(Rajasthan and Gujarat) is adversely affected by the tectonic activity such as collision of the Indian subcontinent with the Eurasian plate which is responsible for the Himalayan and Tibetan Plateau uplift. This collision and its resultants affected the ubiquitous tropical lowland vegetation of the Indian subcontinent(including western India) and are responsible for different types of topographic regions as seen today in the Indian subcontinent. The region is important as it has witnessed a drastic change in climate of the region since the Cenozoic time and also provided opportunities to the western and eastern flora to intermingle. The main basins in western India comprising Cenozoic sequences are: Bikaner-Nagaur, Jaisalmer and Barmer in Rajasthan and Kachchh, Mainland and Saurashtra in Gujarat. These basins are very rich in lignite which is the main source of electric power generation in western India. This lignite is mainly of Eocene in age. The Cenozoic flora of western India was almost tropical growing in well drained areas as compared to arid to sub-humid regions with xeric vegetation today. The reported fossils are represented by leaves, woods, fruits and seeds. The leaves are abundant in the Palaeogene as compared to the Neogene. The Neogene period can be marked by the abundant legumes and dipterocarpaceous remains. The important families viz., Anacardiaceae, Annonaceae, Arecaceae, Calophyllaceae, Clusiaceae, Combretaceae, Euphorbiaceae, Flacourtiaceae, Icacinaceae, Lauraceae, Lythraceae, Meliaceae, Moraceae, Myrtaceae, Pandanaceae and Sonneratiaceae have been reported from the Palaeogene sediments, whereas Anacardiaceae, Araucariaceae, Arecaceae, Combretaceae, Dipterocarpaceae, Fabaceae, Lauraceae, Lecythidaceae, Lythraceae, Malvaceae, Meliaceae, Moraceae, Podocarpaceae, Rhamnaceae, Rhizophoraceae, Rutaceae, Sapindaceae and Sonneratiaceae are known from the Neogene sediments. All the recovered elements strongly indicate the presence of much better climatic conditions in
文摘记录2001—2010年间根据中国中、新生代植物大化石建立的新属25个(新生代的2个,中生代的23个),记录每一属的特征、模式种、地理分布及地质时代。对模式种的创建者、创建年代、所在文献的页码、图版、产地层位、标本保存状态、分类位置以及模式标本保存单位等作详细记录。另有一属(Tharrisia Zhou,Wu and Zhang)模式种的模式标本虽非产自中国,但该属是根据研究中国发现的材料修订含义笼统老属而从中区分出来的,所以也作了记录。
