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本文根据渤海及其沿岸地区地层、地貌、新构造等方面资料,论述了全新世时期渤海海陆变迁历史,分析了变迁原因;根据气候和海陆升降规律,对未来变化趋势作了预测。认为:中全新世中期以前是渤海形成、发展期,以后是收缩、稳定期;现今渤海面貌出现于早全新世,中全新世中期海域范围最大,海平面高于现今海面1—5m;晚全新世以来,海平面和海岸线处于相对稳定状态;控制海陆变化的原因除海平面升降这一区域因素外,不均衡的地壳升降运动、河口和近岸沉积活动以及海洋水文、人类活动等也具有重要作用;全新世冰后期属于第四纪玉木冰期的第三亚间冰阶,晚全新世以来,全球气候在小幅度波动中缓慢向相对寒冷的第四亚冰阶过渡,,大气中 Co_2增加所造成的“温室效应”虽然可以减缓这一进程,但尚不能根本改变气候发展的自然趋势,未来阶段渤海区域海岸将继续保持相对稳定状态,但部分地区因地面沉降,存在较严重海侵威胁。
Based on the data of stratigraphy, geomorphology and neotectonics in the Bohai Sea and its coastal areas, this paper discusses the history of the transition of the sea and land in the Bohai Sea during the Holocene and analyzes the causes of the changes. Based on the climate and the movements of land and sea, the future trends of the changes are predicted. It is concluded that the Bohai Sea formed and developed before the mid-Holocene, and then contracted and stabilized. Nowadays, the Bohai Sea appears in the Early Holocene. The mid-Mid-Holocene has the largest sea area, and the sea level is 1-5m above sea level. Since the beginning of the world, sea level and coastline have been relatively stable. Besides controlling the sea-land change, unbalanced crustal ascending and descending, estuarine and inshore sedimentation, marine hydrology and human activities are also important After the Holocene, since the Holocene, the climate of the third sub-ice belongs to Quaternary Tamaki glacial stage. Since the Late Holocene, the global climate slowly transitioned to the relatively cold fourth sub-ice stage. The increase of Co_2 in the atmosphere Although this process can be slowed down, the natural tendency of climate development can not be fundamentally changed yet. In the future, the coastal areas in the Bohai Sea will continue to be relatively stable. However, in some areas due to land subsidence, there is a more serious threat of transgression .