中文摘要：

全新世大暖期的海平面上升对全球海陆变迁产生了重大影响，重建这一时期的古海岸线对研究古海岸环境演化及预测未来海岸线变迁都具有重要意义，特别是在沿海低洼地带。本文以渤海西南沿岸为典型区域，收集具有完整测年的6kaB．P．左右的51个钻孔埋深数据，内插得到区域沉积层厚度图；再对已有文献中的钻孔高程数据重新订正，根据构造分区拟合出不同区域的相对海平面变化曲线；最后结合区域陆地现代数字高程模型（DEM），利用已有的古海岸线重建模型，构建了6kaB．P．的DEM，进一步分析全球海平面变化及构造运动作用在海岸线变迁中的影响。结果表明，全新世最大海侵时期，渤海西南岸陆地面积减少了2．08-10^4km^2，0m等高线深入内陆最远达约129km，在构造抬升或稳定区域，到达现在海岸6m高程附近，而快速下沉区则可达到8～lOm等高线附近。沿岸相对海平面变化自莱州湾东岸向渤海湾西南岸逐渐降低，最高在现代海平面以上4m多，最低处略高于现代海平面，受构造升降作用影响明显。基于雷达剖面进一步估算，全球海平面变化在相对海平面变化的贡献量为上升1．52m，构造作用的影响为，莱州湾东岸3m，莱州湾南岸0．37m，现代黄河三角洲地区-0．36m，渤海湾西南岸-0．70m。

英文摘要：

Sea level rise during the Megathermal of the Holocene had a significant impact on the global marine and terrestrial changes. The reconstruction of the paleoshoreline in this period is of great important for understanding the coastal paleoenvironmental evolution and predicting the future shoreline changes, especially in low-lying coastal areas. In this paper, the southwestern coast of the Bohai Sea was chosen as a typical region. Regional sediment thickness since 6ka B.P. has been estimated from the drilling depth data with the exact dating around 6ka B.P. spread all over the study coastal area. The collected elevation data of core have been revised. Then the curve of relative sea level change can been established using polynomial fitting method from these processed data based on the geological structure partition. Final, the Digital Elevation Model （DEM） in 6ka B.P. can be obtained according to the model of paleoshoreline reconstruction combined with modem DEM. Further integration of radar profiles, the contribution of sea level rise and land subsidence on the shoreline change will be estimated. The results indicated that the land area in the southwestern coast of the Bohai Sea decreased by 2.08 × 10^4km^2 during the Holocene transgression period, and 0m contour can arrived the most far 129km inland, in the tectonic uplift or stability regions to reach near 6m contour, even reach the vicinity of 8- 10m contour in rapid tectonic sinking areas. From the east coast of the Laizhou Bay to the southwestern coast of the Bohai Bay, the height of relative sea level is gradually decreasing, more than 4m in the highest area, the lowest point is slightly higher than the modern sea level obviously affected by tectonic movements＇ role. Based on the radar cross section further estimates, the contribution of global sea level is 1.52m above the modern sea level, and the impact of tectonic is 3m in the eastern coast of the Laizhou Bay, the southern Laizhou Bay is 0.37m, the modern Yellow River delta is -0.36m, and the south