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新泽西州南部为一水动力状态受潮汐控制的障壁海岸。大湾,这一障壁后盐沼复合体中通过潮沟进水的开阔浅水泻湖,看来是由两个进潮口从内陆架输入碎屑物的沉积凹陷。该系统的潮汐水动力学和沉积堆积型式的研究为一种沉积作用数值模型提供了基础。该模型预测,在穿切大湾的沿海运河附近有粗粒(>20μm)沉积物快速堆积,主要发育与风暴有关的沉积事件。观测结果总体上证实了这种预测。砂在与两条主潮沟(大潮沟及英格勒姆联潮道)相联的涨潮三角洲上和在沿海运河中快速堆积。细粒碎屑主要呈有机矿物集合体搬运,并缓慢堆积(<2.7mm/y)在大湾西南部及东部。由于三角洲上的波浪作用和涨潮流(U_(0.4)dma× 42mm/s),浅水(0.6m)湾中常出现底部沉积物的再悬浮。可是,大湾多数地区的潮流速度很低(U_(0.4)dmax<18cm/s),某些地方还有大型藻类存在,却助长了净堆积作用的发展。尽管沉积物堆积数据变化很大,其堆积速率的范围却表明,大湾的近代淤高,与4mm/y 的局部海面上升是大体相当的。
Southern New Jersey is a tidal bank controlled by the tide of water. Grand Bay, an open shallow lagoon through the trough ditch in this post-Barrier salt marsh complex, appears to be where sediment sags of debris are introduced from the inland shelf by two taps. The study of tidal hydrodynamics and sedimentary accumulation patterns of the system provided the basis for a numerical model of sedimentation. The model predicts rapid accumulation of coarse-grained (> 20μm) sediments near the coastal cany of Chendaiwan, mainly for storm-related sedimentary events. The observations generally confirm this prediction. The sand is rapidly deposited on the high tide delta associated with both main tidal channels (tidal channel and Ingram Omnipitch) and in the coastal canals. Fine-grained crumbs are mainly transported by organic-mineral aggregates and slowly accumulate (<2.7mm / y) in the southwestern and eastern parts of the Grand Bay. Sediment of the bottom sediments often occur in the shallow water (0.6m) due to wave action and rising tides in the delta (U_ (0.4) dma × 42 mm / s). However, tidal current is very low in most parts of the Great Bay (U_ (0.4) dmax <18 cm / s) and the presence of large algae in some places contributes to the development of net accumulation. Although the sediment accumulation data vary greatly, the range of its accumulation rate shows that the modern depositional height of the Grand Bay is roughly equivalent to the local sea level rise of 4 mm / y.