通过对长江三角洲泰州地区TZK3钻孔沉积物沉积特征、微体古生物的综合分析,结合系统的高分辨率AMS 14C、OSL测年,讨论了该地区末次冰期以来沉积环境的演变过程.结果显示,TZK3孔自下而上可分为6个沉积单元:1)MIS 4,砂砾层,不含有孔虫,为河床相;2)MIS 3,粉砂,含有贝壳碎片、小海贝、海相腹足类口盖,为河口相;3)MIS 2,含粘土粉砂,含少量介形虫,为河漫滩相;4)12.1～10.5cal.ka B.P.,粉砂,未见有孔虫,为河床相;5)10.5 ～6.9 cal.ka B.P.,粉砂,零星见个体非常小的有孔虫,潮汐层理发育,为受潮汐影响的河漫滩;6)6.9～4.3 cal.ka B.P.,粉砂,含有大量有孔虫,为河口砂质沉积.对比研究发现,全新世长江三角洲的最大海泛面时期为6.9 cal.ka B.P.,黄桥砂坝发育的年龄区间为7.6～4.3 cal.ka B.P.,为潮成砂坝,其发育主要受长江径流、河口潮汐流和亚洲季风的影响.%The core TZK3 is located in the southeast Taizhou City(32°23′N,120°05′E),the north of Changjiang River delta.The lithology of the core is composed of silt and silty sand.Clay.,sand,coarse sand and gravel are also found.In this study,for the upper part of the core (70 m-thick sediment),50 samples were taken for micropaleontology test with interval of 1.0～ 1.5 m,and 8 samples for AMS C-14 and 1 sample OSL dating,respectively.The results show that the core TZK3 can be divided into 6 sedimentary units from bottom to top:(1) 70.00 ～ 46.05 m (MIS 4),the lithology is gray silt,fine sand,coarse sand and gravel,indicating river bed phase.The age is 109.28±8.86 ka in 69.5～69.7 m through OSL dating,showing deposition stage is MIS 4.(2)46.05～44.99 m (MIS 3),silt with sea shell fragments and shellfish,indicating a weak ocean influence,such as the estuary.The calendar calibration age is 27613 cal.a B.P.in 45.7 m,corresponding to the Gehu transgression.(3)44.99～ 43.92 m(MIS 2),the lithology gray-green clay with silt.There is plant debris and a small amount of ostracods in the sediment,such as Ilyocypris bradyi and Ilyocypris sp.,suggesting a paleosoil.(4)43.92～37.95 m,with an age of 12.1 ～ 10.5 cal.ka B.P.,gray silt and fine sand with horizontal bedding from the river bed.There is shell fragments moving from other place and erosion surface with lower strata.(5)37.95～29.50 m,with an age of 10.5～6.9 cal.ka B.P.,gray silt,fine sand and silt with horizontal bedding.The sediment contains plant debris and foraminifera with small form,such as Ammonia sp.,Cribrononion sp.,Cribrononion incertum.In this phase,the sea level continued to rise,the transgression rate was higher than the sedimentation rate of the sediments,and the coastline continued to move westward.The study area was covered by floods from the tidal.(6)Whose with the depth of 29.5～0 m,with an age of 6.9～4.3 cal.ka B.P.,silt containing a lot of foraminifera,such as Ammonia beccarii/Ammonia tepida Group.Due to the increase in the Asian monsoon and precipitation,the capacity can be enhanced in the upper reaches of the Changjiang River.The sediment accumulation rate accelerated,and the coastline move to the east.The study area began to develop Huangqiao estuary sand dam.Compared with the records in the Changjiang estuary,the maximum transgression of the Changjiang River delta occurred at 6.9 cal.ka B.P.and the age of the Huangqiao sand bar was developed at 7.6～4.3 cal.ka B.P.,which is mainly affected by the Asian monsoon,estuary tide and runoff in the Changjiang River.
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