基于地统计学的粒径输运趋势分析在滦河水下三角洲的应用  

Application of geostatistical grain size trend analysis in the Luanhe River Subaqueous Delta

作　　者：于晓晓 谷东起 闫文文 孙惠凤 李平 张志卫 瞿洪宝 YU Xiaoxiao;GU Dongqi;YAN Wenwen;SUN Huifeng;LI Ping;ZHANG Zhiwei;QU Hongbao(Institute of Oceanology,Chinese Academy of Science,Qingdao 266071,China;University of Chinese Academy of Sciences,Beijing 100049,China;First Institute of Oceanology,Ministry of Natural Resources,Qingdao 266061,China;Marine Geological Survey Institute of Hainan Province,Haikou 570206,China)

机构地区：[1]中国科学院海洋研究所海洋地质与环境重点实验室,青岛266071 [2]中国科学院大学,北京100049 [3]自然资源部第一海洋研究所,青岛266061 [4]海南省海洋地质调查研究院,海口570206

出　　处：《海洋地质与第四纪地质》2020年第4期204-213,共10页Marine Geology & Quaternary Geology

基　　金：国家自然科学基金-山东联合基金重点支持项目“黄河三角洲地貌演变的动力机制与环境效应”(U1706214)。

摘　　要：利用均匀分布于滦河水下三角洲的85个表层沉积物粒度数据,基于地统计学的粒径输运趋势方法对滦河水下三角洲沉积物的输运趋势及影响因素进行了研究.半方差函数分析表明,以0.015°(地球大圆弧度)为插值半径加密后(规则分布)的平均粒径半方差值具有随变程增加而增加的趋势,并在变程值达到0.09°后趋于稳定,而原始数据的半方差值与变程相关性较差.以此(0.09°)为特征距离计算的粒径输运结果显示,滦河水下三角洲南部水深12 m以浅区域粒径输运趋势以向南为主,北部具有向西和向北的趋势;水深12~15 m范围内粒径输运趋势近似西南方向,且趋势较大;南部水深15 m以深地区粒径输运趋势方向为西北向,北部为东南向.粒径输运趋势整体上与实测潮流、余流和泥沙输运方向一致,显示潮流对研究区沉积物的输运具有控制作用.滦河水下三角洲地区沉积环境和输运趋势受河流、波浪、潮流、残留沉积和地形等多种因素影响,粒径输运趋势仅能够较好地解释潮流影响,对于残留沉积等复杂沉积过程的解释则相对有限.With the grain size data of 85 surface sediment samples collected from the Luanhe River Subaqueous Delta(LRSD),we studied the sediment transportation trend using the geostatistical grain size trend analysis method(GSTA)in this paper.It is revealed that the semi-variance value of mean grain size in a regular grid increases with distance until the distance reaches 0.09 decimal degree,while the irregular data shows no such a correlation with distance.Thus,the decimal degree of 0.09 is chosen as the character distance for grain size trend analysis.It is further revealed that the direction of the semi-variance is 55°,which is parallel to the tidal current,suggesting that the character distance is tide related.Geostatistical GSTA result further indicates that the net sediment transport trend direction in the south area,where the water depth is less than 12 m,is in southwest,whereas that in the north area,where the depth is less than 12 m,is in west and southwest directions.In the area with water depth between 12 and 15 m,the net sediment transport trend is in southwestern direction,roughly parallel to the coast line.In the area under water depth more than 15 m,the net sediment transport trend is northwest in direction in the southern part,but southeast direction in the northern part.The grain size net sediment transport trends mentioned above are similar to the field measured tidal current,residual current,and sediment transport directions suggesting a tide predominated sediment transportation.However,relict sediments,wave,river and bedform are more complex,which may give influences the grain size net sediment transport trend.The research results of the net sediment transport trend in LRSD may reveal the influence of tidal current.However,for an explanation to relict sediments,further researches are required.

关 键 词：地统计学 粒径输运趋势 特征距离 潮流 滦河水下三角洲 

分 类 号：P736.21[天文地球—海洋地质]