The Chinese Maar Drilling Programme A Chinese–German Cooperation for Paleoclimatic Reconstructions

PAGES NEWS, VOL.9, N°2, JULY 2001 Over the last ten years, interest in high resolution (decadal to annual) paleoclimatic studies has grown rapidly. The climate system contains numerous processes on subdecadal time scales, for example the “North Atlantic Oscillation” (NAO) and the “El Niño–Southern Oscillation” (ENSO). In order to capture such modes, it is necessary to investigate paleoclimate with annual resolution. A broad range of high resolution paleoclimatic records with annual or subannual resolution (e. g. ice cores, corals, and tree rings) are available for the late Holocene. Further back in time the records are scarce. In contrast, continental records of annual to seasonal resolution are available in maar lakes as far back as 101 ky (Lago Grande di Monticchio, Italy, Allen et al., 1999, Brauer et al., 2000). Even large lakes can contain excellently varved records (Ken–Tor et al., 2001). The Chinese Maar Drilling Program was established in order to target these records in East Asia. To date, coring campaigns have been organized in south and northeast China (ProjectI & II, Figure 1). The Huguang Maar record from South China documents the last 78,000 years. Unfortunatly, this paleorecord was not varved but it was none the less possible to establish an age model based on AMS14C data and high resolution paleomagnetic measurements. The chronology is sufficiently robust to allow comparison with the marine sequence of Blake Outer Ridge (Nowaczyk et al., 2000). Figure 2 reveals the climate change reconstructed in this record since Marine Isotope Stage (MIS) 5a. The Younger Dryas is marked by a peak in inorganic carbon and smaller amounts of organic carbon (Mingram et al., 2001). Initial short and freeze cores in Sihailongwan maar in Northeast China provide an annually resolved reThe Chinese Maar Drilling Programme A Chinese–German Cooperation for Paleoclimatic Reconstructions LIU JIAQUI1, LIU TUNGSHENG1 & JÖRG F. W. NEGENDANK2 1Institute of Geology & Geophysics of the CAS, Beijing. 2GeoForschungsZentrum Potsdam, Germany. neg@gfz-potsdam.de