Rapid Holocene Evolution and Neotectonics of the Albanian Adriatic Coastline
Rapid Holocene Evolution and Neotectonics of the Albanian Adriatic Coastline
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阿尔巴尼亚亚得里亚海海岸线的全新世快速演化和新构造运动
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
R. Arthurton
中科院分区：
文献类型：
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作者：
S. Mathers;D. Brew;R. Arthurton
1986年阿尔巴尼亚亚得里亚海海岸的高分辨率陆地卫星TM图像与1943年获得的航空照片和出版的文献进行了比较，以破译沿海平原晚全新世沉积物的沉积结构和演变。这条海岸线是微潮和波浪作用为主;和丰富的沉积物提供的河流排水隆起的山区内部这一构造活动区。自大约6000年前相对海平面上升减缓以来，沿海平原已扩展至40公里。沿海平原的内陆部分主要是平行风暴海滩脊，而沿海边缘表现出对称到不对称的波浪主导的三角洲和沙嘴三角洲，包括切断泻湖的多样性。一个成因模型来解释波为主的三角洲在阿尔巴尼亚海岸的变化，提出了一个频谱的形式之间的adjuding对称尖状三角洲形成的双向沿岸漂移和高度不对称的吐三角洲形成的单向沿岸漂移。剥离转换导致废弃;对称的形状被波浪作用变得平滑，而三角洲则成为分离的障壁海滩，通过冲刷向岸上迁移，将自己焊接到海岸上。在这种情况下，后障截止泻湖的保存潜力非常低。两个大得多的泻湖（现已部分开垦）位于卡拉瓦斯塔和纳尔塔，位于海滩脊带内;两者都有一个平行于已知的后新近纪断层的直向海边缘。泻湖表现出差异沉降，这被认为是新构造的起源，存在一个60公里长的地堑或半地堑结构连接两个地区的沉降建议解释所观察到的现象。在过去的1,000- 2,000年里，沉降达5-10米。
High-resolution 1986 Landsat TM images of the Adriatic coast of Albania have been compared with aerial photographs obtained in 1943, and published literature, in order to decipher the sedimentary architecture and evolution of the late-Holocene deposits of the coastal plain. This coastline is microtidal and dominated by wave action; and abundant sediment is supplied by rivers draining the uplifted mountainous interior of this tectonically active region. The coastal plain has prograded up to 40 km since relative sea level rise slowed down around 6000 years BP. The inland parts of the coastal plain are dominated by parallel storm beach ridges whilst the coastal fringe exhibits a diversity of symmetrical to asymmetrical wave-dominated deltas and spit-deltas encompassing cut-off lagoons. A genetic model to explain the variability of wave-dominated deltas on the Albanian coast is proposed showing a spectrum of forms between prograding symmetrical cuspate deltas formed by bi-directional longshore drift and highly asymmetrical spit deltas formed by uni-directional longshore drift. Avulsive switching causes abandonment; the symmetrical forms become smoothed out by wave action whereas the spit-deltas become detached barrier beaches that migrate onshore by washover, welding themselves onto the coast. The back barrier cut-off lagoons in this setting have a very low preservation potential. Two much larger lagoons, now partly reclaimed, at Karavasta and Narta, lie within the belt of beach ridges; both have a straight seaward margin parallel to known post-Neogene faulting. The lagoons exhibit differential subsidence which is regarded as neotectonic in origin; the presence of a 60 km long graben or half graben structure linking the two areas of subsidence is suggested to explain the observed phenomena. Subsidence up to 5-10 m is indicated within the last 1,000- 2,000 years.