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Xiao G.-Q.,Hubei University | Xiao G.-Q.,Tianjin Center | Xiao G.-Q.,Key Laboratory of Muddy Coast Geo environment | Yang J.-L.,Tianjin Center | And 8 more authors.
Geological Bulletin of China | Year: 2014

It is of great importance to establish reliable chronologic framework in Binhai area for understanding the late Cenozoic depositional environment change, neotectonic movement and evolution history of paleoenvironment. In this paper, the authors present the magneto-stratigraphic investigation result in drill hole G2 (1226m), which is the longest drill hole in the Tianjin coastal area. On such a basis, the chronostratigraphic subdivision and its tectonic significance were also discussed. The results show that the core of this drill hole began deposition at about 8.5Ma BP. The strata of 1226~658m may be correlated to late Miocene and assigned to upper member of Guantao Formation, the strata of 658~303m belong to Pliocene Minghuazhen Formation, and the upper strata of more than 300m belong to Quaternary, including Mapengkou, Tonglou, Tanggu and Tianjin formations. The basal lower boundary of Holocene is identified at about 19.4m by 14C dating. Given the chronostratigraphic scale, two stages of relatively high sedimentation rate (>200m/Ma) can be revealed from drill hole G2, i.e., 8.5~6.43Ma and 3.58~3.03Ma, respectively. Both epochs have good comparability on the time scale with extension and uplift of the Tibetan Plateau. It is suggested that the uplift of plateau might also have had a significant impact on sedimentary and tectonic movement of the North China plain. ©, 2014, Science Press. All right reserved.


Wang F.,Tianjin Center | Wang F.,Key Laboratory of Muddy Coast Geo environment | Wang F.,Tianjin Institute of Geology and Mineral Resources | Chen Y.-S.,Tianjin Center | And 14 more authors.
Geological Bulletin of China | Year: 2014

Four drilling cores were collected from coastal lowland of Bohai Bay, and AMS 14C dating method was used to study the age of the second marine layer in coastal low land of Bohai Bay. The dating results of the samples collected form the second marine layer show that the ages are all older than 43.5ka BP, which indicates that the formation of the second marine layer occurred in early MIS3 or MIS 5 rather than 23~39ka as previously considered. Based on previous stratigraphic studies, the authors hold that systematic investigation should be carried out for the age of the second marine layer on coastal lowland of Bohai Bay. ©, 2014, Science Press. All right reserved.


Wang F.,Tianjin Center | Wang F.,Key Laboratory of Muddy Coast Geo environment | Wang F.,Tianjin Institute of Geology and Mineral Resources | Li J.,Tianjin Center | And 15 more authors.
Earth Science Frontiers | Year: 2016

We used an AMS 14C and OSL dated core (QX01) from the coastal lowland of Bohai Bay to decipher the late Pleistocene paleo-environment change and river channel infilling. Sedimentary facies, grain size, large-amplitude changes in benthic foraminifer's assemblage and diatom assemblage composition indicate that the major environmental changes occurred during the last 40000 years in the study area. The results show that 6 sedimentary stages were identified, which is (1) 30-29.72 m: fluvial deposition; (2) 29.72-29.4 m: transgression deposition, >43.5 ka; (3) 29.4-17.7 m: sandy sediments, river channel filling, ~37.9-29.7 ka; (4) 17.7-13.2 m: sediments finning from sand to clay, ~29.7-8 ka, the environments from river channel infilling to swamp; (5) 13-5 m: 8-4 ka, Holocene transgression deposits, the environments from fresh water swamp, to brackish swamp or salt mash, to shallow sea, to salt marsh, most strongest marine influence happened during 6000-5750 cal BP, then retreat; (6) 5-0 m: since 1.7 ka, the environment was controlled by river, and it is flood plain deposits during this period. The sedimentary changes were correlated with sea level change very well. During MIS 4 or 6, the sea level was relatively lower, the river cut down and river channel formed, then the river channel was infilling during 37.9-29.7 ka of MIS 3, when the sea level was relatively higher, the height of the river channel were infilled from -24.2 m to -11.8 m of Huanghai 85 highness. Then the last glacial maximum came, the sea water retreated out of Bohai Sea and the study area was swamp or shallow lake; the sedimentation stopped or at a very low level till the early Holocene, 8 ka. With the end of the last glacial maximum, the sea water came back again during 8-4 ka, represented by fresh swamp, salt marsh, and shallow sea deposits. Then the deposition stopped again, till 1.7 ka, with the role of the river, the environments became floodplain deposits. Moreover, two sedimentary break were identified, which is the break during last glacial of low sea level, and the break during 4-1.7 ka, when the marine influence finished or sea water retreated from the study area, but the role of the river had not started. © 2016, Editorial Office of Earth Science Frontiers. All right reserved.


Chen Y.-S.,Tianjin Center | Chen Y.-S.,Key Laboratory of Muddy Coast Geo environment | Wang F.,Tianjin Center | Wang F.,Key Laboratory of Muddy Coast Geo environment | And 9 more authors.
Geological Bulletin of China | Year: 2014

Taking cores from three drill holes along the western coast of Bohai Bay as the study basis and collecting materials through cutting through the upper marine bed deposited during Holocene as samples, the authors dated shells and charcoals by AMS 14C and calculated the average sedimentation rate. The spatial-temporal relationship between the Holocene sedimentation rates of drill holes and sediments transported by rivers was discussed combined with grain size and development of adjacent ancient river delta. The results indicate that various sedimentation rates occurred in different periods in Holocene and such a variety reveals different sediment supplies along the western coast of Bohai Bay. From early Holocene to early period of mid-Holocene, the low sedimentation rate (0.03~0.07cm/a) and coarse sediments along the whole western coast presented less impotent fluvial input at that time. During 6.43~4.96ka cal BP, the rising sedimentation rate (0.59~0.93cm/a) and upward-coarse grain size succession implied that Chaobai River, Yongding River and Luanhe River dumped sediments in the northern part of the west coast of Bohai Bay. In 3.68~2.67ka cal BP, the Yellow River downloaded its sediments in the southern part of the area indicated by the high sedimentation rate (0.27~1.4cm/a) and upward-coarse grain size succession, while Haihe River emptied its sediments to the middle part of the area in 2.29~0.24ka cal BP with sedimentation rate being 0.55~0.91cm/a. ©, 2014, Science Press. All right reserved.


Wang F.,Key Laboratory of Muddy Coast Geo environment | Wang F.,Tianjin Institute of Geology and Mineral Resources | Li J.,Key Laboratory of Muddy Coast Geo environment | Li J.,Tianjin Institute of Geology and Mineral Resources | And 6 more authors.
Marine Geology | Year: 2015

This study used benthic foraminifera, diatom, total organic carbon, organic carbon isotope ratios, C/N ratios, and grain-size data from three AMS14C dated cores collected from the western coastal lowland of Bohai Bay, China, to elucidate the coastal response to relative sea-level change during the Holocene. A layer of peaty clay overlaying early Holocene terrestrial sediment was dated to 8400-8000cal BP, and the peaty material in the sediment suggests possible vegetation cover before the mid-Holocene marine inundation in the study area. Sedimentary facies and changes in diatom and foraminifera assemblages suggest a five-stage marine transgression-regression history. During the first stage from 8000 to 7855cal BP, the study area was inundated primarily by freshwater swamp. During the second stage from 7855 to 6000cal BP the study area was under brackish water influence. In the third stage from c. 6000 to 5750cal BP, the study area experienced marine influences, and by this time the Holocene transgression reached its maximum landward location and height. This was followed by a period of regression since c. 5750cal BP. During the last 4000years, the study area was influenced by freshwater and became a floodplain environment. Thus, this study reveals that the most landward position of the Holocene marine transgression was situated somewhere between the coring locations of DC01 and QX01, which is about 80km inland from the present shoreline. This means the west coast of the Bay has advanced at an average speed of c. 13m/a since the mid Holocene. The relative sea level around 6000cal BP was at -2.64±0.1m. © 2014 Elsevier B.V.

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