河北昌黎典型海岸沙丘的沉积构造及其发育模式  

Sedimentary structure and development model of typical coastal dunes along the coast of Changli County,Hebei Province

作　　者：姜锋[1,2] 李志忠[1,3,2] 靳建辉[1,3,2] 邓涛[1,2] 申健玲 于晓莉[1,2] 苑秀全 赖海成 陈秀玲[1,3,2] 

机构地区：[1]福建师范大学地理科学学院,福建福州350007 [2]湿润亚热带生态地理过程教育部重点实验室,福建福州350007 [3]福建师范大学地理研究所,福建福州350007

出　　处：《海洋学报》2016年第7期107-116,共10页

基　　金：国家自然科学基金(41271031;41301012);国家自然科学基金委员会--福建省人民政府促进海峡两岸科技合作联合基金(U1405231);福建省科技厅公益类科研院所专项基金(2013R09);福建省自然科学基金(2014J01151)

摘　　要：采用探地雷达探测了昌黎海岸沙丘区典型横向沙脊和新月形沙丘的沉积构造,据此初步揭示了研究区海岸沙丘的沉积序列特征和发育过程。结果表明,昌黎海岸带在2 000aBP波浪作用下发育滨岸沙坝,沙坝主要以向海向陆缓倾斜的沉积构造为主,现今的风成沉积发育于滨海相沙坝之上。海岸带向海一侧经历了潮上带前丘到横向沙脊的过程,横向沙脊在东北风的作用下主要发育向陆倾斜的高角度交错层理,同时由于向岸合成风力的阶段性变化,这些层理的倾角略有差异,记录了海岸带风沙活动的周期性变化;内侧新月形沙丘由4组倾角不同的层理组成,被较大规模的二级界面分隔,复合新月形沙丘(链)经历了由盾状沙堆到典型新月形沙丘的加积发育并遭受风蚀的过程。In order to detect sedimentary sequences and formation history of transverse ridge and barchan dune in the Changli coast, images from Ground-penetrating radar （GPR） are interpreted. The result shows that sand barrier formed under wave action along the coast 2 000 years ago. In landward and seaward slope of the barrier, reversed dip cross-lamination developed respectively. High transverse ridge and barchan dunes formed on the sand barrier, which is the basis of Aeolian dunes. The transverse dune evolved from fordunes in supratidal zone. High angle landward-dipping reflectors dominate the section inside the transverse dune. Under the reaction of the northeast wind, the dip direction of these bedding is SWW. Meanwhile, secondary changes of wind lead to the differences in angle of bedding, which record phases of wind-,sand activity. The processes of barchan dune are more complex. According to some extensive reactivation and erosion surfaces in the barchan dune, four sedimentary units can be distinguished. The different structures of units indicated that the barchan dune experiecned a transition from a dome to a typical barchan dune, and got eroded thereafter.

关 键 词：探地雷达 GPR 横向沙脊 新月形沙丘链 沉积构造 沉积序列 发育模式 河北 昌黎 

分 类 号：P736.213[天文地球—海洋地质]