Despite numerous research efforts in recent decades, the precise time of this event has remained a puzzle until now. New evidence in helping settle this issue is provided by Prof. Deng Shenghui and his colleagues in their paper newly published in Science in China (2009, vol.52).
Geological studies have demonstrated that during the early Paleozoic, an interval from 450-300 million year ago, the Siberian paleo-land was thousands kilometers away from the North China paleo-land, which is very different from their present situation. An immense ocean of thousands kilometers wide, namely the Paleoasian Ocean, separated these two paleo-lands. During the Carboniferous and Early Permian (about 360-270 million year ago), the North China paleo-land was located near the equator, where subtropic-tropic type of flora grew, named as "the Cathaysia Flora". In contrast, the Siberian paleo-land was located at high latitude, where temperate flora was distributed, known as "the Angara Flora". These two types of floras are very distinctive and do not mix with each other because of the geological barrier and their separate niches in different climatic zones.
Prof. Deng and his collaborators concluded that the time of the Paleoasian Ocean's disappearance is the end of the Permian, about 251 million years ago, based on their study of land plant fossils. Several years ago, Deng and his research group found many plant fossils from the rocks that were formed in the Late Permian during their stratigraphical and paleontological investigation in Heilongjiang, Northeast China. These fossils could be divided into two types after detailed identifications. One belongs to Angara Flora and the other to Cathaysia Flora. So, these plant fossils represent a mixed flora. The mixed flora implies that the Angara type plants lived together with some Cathaysia type plants at this location in the Late Permian. This means that the Paleoasian Ocean, once a barrier of plant immigration, must have disappeared in the Late Permian, and those plants grew previously in North China paleo-land now immigrated to the Siberian paleo-land. Therefore, Deng and his colleagues suggested that the Paleoasian Ocean finally closed at the end of the Late Permian, about 251 million years ago.
Prof. Deng is a paleontologist in the Research Institute of Petroleum Exploration and Development, PetroChina, which is the largest national oil corporation in China. In order to explore more oil and gas resources, many basic geological problems should be solved first, such as the forming age of the oil and gas-bearing rocks, the paleogeography, paleoclimate, and paleoecology etc. Fossils, fossilized bodies and traces of ancient animals and plants, play an extremely important role in study of these basic geological problems. Prof. Deng and his paleontological group focus on the researches of various fossils.
The study was supported first by the Key Research Project of PetroChina and then by the National Program on Key Basic Research Project (Grant No: 2006CB701400).
Reference: Deng S H, Wan C B, Yang J G. 2009. Discovery of a Late Permian Angara-Cathaysia mixed flora from Acheng of Heilongjiang, China, with discussions on the closure of the Paleoasian Ocean. Science in China, Series DFEarth Science, vol. 52, no.11: 1746-1755.
Shenghui Deng | EurekAlert!
Antarctic Ice Sheet mass loss has increased
14.06.2018 | Technische Universität Dresden
WAKE-UP provides new treatment option for stroke patients | International study led by UKE
17.05.2018 | Universitätsklinikum Hamburg-Eppendorf
In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.
Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
20.06.2018 | Materials Sciences
20.06.2018 | Information Technology
20.06.2018 | Information Technology