TRANSGRESSIVE RECORDS OF LAST MILLION YEARS IN THE BOHAI SEA,CHINA: EVIDENCE FROM FORAMINIFERA AND OSTRACODA OF CORE BH08

Based on the quantitative foraminiferal and ostracod study of 271 samples taken from the Core BH08 (38.28°N,119.99°E,water depth 25 m,core length 212.4 m),a total of 16marine beds,labeled M1 to M16 from top to bottom,has been recognized.The chronological study demonstrates that the 16 marine beds were deposited during the interglacials of the last million years.The paleoenvironmental data inferred from foraminiferal and ostracod communities may be grouped into 5biofacies with marine influence from strong to week:offshore inner shelve (M9),nearshore inner shelve with weak river influence(M1 and M2),pro-delta or nearshore inner shelve with moderate river influence (M6,M7,M8,M10,and upper M13),delta front,tidal flat of river mouth or semi-closed brackish lagoon under the river control (M3,M4,M5,M11,M12 and M14 to M16),and supra-littoral marsh or shallow lake of low salinity (top M3,some interlayers of M4 and bottom M16).