Evolution of the “Hainan Delta” as response to the paleo-environment
since the Late Pleistocene at the South China Sea northwestern shelf (ERES)

Bilateral Polish / Chinese Research Project
between Guangzhou Marine Geological Survey, China, and University of Szczecin, Poland

GENERAL PROJECT DESCRIPTION

 


1. Research project objectives/ Research Hypothesis.

The main objective of the project is to interpret sedimentological and seismic data offshore Hainan Island, South China Sea, to develop a high-resolution sequence-stratigraphic framework of the shelf and slope sediments to be interpreted genetically as a response to sea-level, climate, and environmental changes between Marine Isotope Stages MIS 4 and MIS 2. The regional results have to be correlated with global sea-level and paleoclimate records to identify global signatures of sea-level and climate periodicities during the Last Glacial Period (such as D/O oscillations). This objective will be pursued by testing the hypothesis that the “Hainan Delta” discovered during preceding studies of the proposing team reflects global sea-level fluctuations between MIS 4 and MIS 2 and the supply of erosional products of Hainan Islands pointing at changes of climate parameters such as monsoon dynamics.

research area

Fig. 1. Digital elevation model of the Beibu Gulf and adjacent terrestrial areas.



2. Research project methodology.

The key role plays the 100 m sediment core #ZBW which was drilled in October 2015, based on recommendation of the Polish/Chinese research team at position 17°10’26.448“ N, 109°01’40.876”E offshore Hainan at a water depth of 100.5 m having penetrated the sediments of the “Hainan Delta“. The sediment core has been sub-sampled by the proposing team together with the Chinese partners of the Guangzhou Marine Geological Survey (GMGS) and China University of Geosciences Wuhan (CUG) in May 2016. The measurements of the textural, chemical and paleontological facies of the samples will be studied by the Polish and Chinese project partners according to a coordination agreement. At the University of Szczecin, the new NATURAL SCIENCE EDUCATION AND RESEARCH CENTRE providing the labs and facilities for sedimentological, mineralogical, geochemical and micropaleontological studies and plays an extraordinary role in this respect. An age model will be elaborated for the #ZBW core including AMS-, OSL- and paleomagnetic datings. This age model will allow the conversion of core depth to the geological time scale so that the variation of facies down-core and its interpretation as changing climatic, environmental and oceanographic (sea-level) conditions can be interpreted by time series analysis. Mineralogical provenance analyses will help to identify the sources of sediments accumulated in the Hainan Delta. The compilation of seismic data is of special importance because of the key-role of sequence stratigraphy for the project. Delta geometry will be estimated by the spatial interpolation of seismic and sediment core data within the frame of GIS approaches. A sea-level curve to be reconstructed from proxy-data and the conversion of the scaling of sediment data from space- to time leads to sequence stratigraphic models. Paleobathymetric models are to be constructed as scenarios by back stripping sediment layers within the frame of the sequence stratigraphic models. Rates of the tectonic uplifting of Hainan Island base on maps of vertical crustal movement and OSL-datings of river terraces.

NAHAI_503

Fig.2. Drillship Nanhai-503 used to obtain core ZBW.



3. Expected impact of the research project on the development of science and society.

The “Hainan delta” form a “hot spot” to study environmental changes during MIS 3. Outcomes of the project to be reported in highly ranked international journals will have markable impact on paleoclimatology in terms of paleo-monsoon dynamics but also on teleconnection with climate phenomena at higher latitudes. At the University of Szczecin a main focus of the project is to integrate ESRs and students to provide a targeted start of an international academic career. The co-operation with Chinese partners, but also with other highly acknowledged international institutes will have a strong impact on the development of the University of Szczecin as a marine research site and will raise its attractiveness for scholars, and students from Poland and abroad.

methodology

Fig. 3. Flowchart for core measurements and sub-sampling within the ERES project.


 

ERES expedition_2017

Fig.4. Members of the ERES team at the Hainan Island, 2017

 

ACKNOWLEDGMENTS

The research funded by the Polish National Science Center on the basis of the decision: DEC-2016/21/B/ST10/02939.