河南东部平原第四系含水层结构研究

A study on the structure of the quaternary aquifer in the eastern plains of Henan Province

河南东部平原作为我国重要的农业区,区内的第四系含水层结构复杂多变,含水层结构尚未明确,查明研究区地下水的空间分布和含水层属性结构的特征尤为重要。本文基于Groundwater Modeling System 5.0软件,利用钻孔159眼,平均密度2.4眼/1 000km^(2)。对钻孔数据进行时代统一划分,确定地层合并原则及分层编号,建立第四系含水层结构模型,对河南东部平原区第四系地质结构和含水层属性特征进行研究。结果表明:(1)河南东部平原区第四系含水层中细砂、细砂、粉砂、粉细砂较多,但分布不均匀。(2)研究区内浅层地下水渗透系数在岗状平原小于1 m/d,低缓平原1~30 m/d,郑州北部、郏县西南、叶县西部大于30 m/d;中深层含水砂层厚度为20~50 m,在开封县、漯河东部、新蔡县、太康县等地60~80 m。(3)研究区导水系数介于50~200 m^(2)/d上下限值之间,个别地级县(诸如开封县、新蔡县)、市(诸如商丘市、漯河市)地区导水系数超过了在300 m^(2)/d,更有甚者超过了500 m^(2)/d。研究结果对掌握河南东部平原地下水赋存规律、地下水资源的持续开发和合理利用有着重要的意义,从而达到综合开发和实行科学、优化管理水资源目的。

As an important agricultural area in China,the Quaternary aquifer structure in the eastern plains of Henan is complex and variable,and the aquifer structure has not yet been clarified,so it is particularly important to find out the spatial distribution of groundwater and the characteristics of the aquifer property structure in the study area.This paper is based on Groundwater Modeling System 5.0 software and utilises 159 eyes in boreholes with an average density of 2.4 eyes/1000 km^(2).The borehole data were divided into epochs,the principle of stratigraphic consolidation and stratigraphic numbering were determined,and the Quaternary aquifer structural model was established to study the geological structure of the Quaternary and aquifer attribute characteristics in the plain area of eastern Henan Province.The results show:(1)The Quaternary aquifer in the plain area of eastern Henan has more fine sand,fine sand,silt,and powdery fine sand,but the distribution is uneven.(2)The permeability coefficient of shallow groundwater in the study area is less than 1m/d in the granular plain,1~30 m/d in the low and gentle plain,and more than 30m/d in the north of Zhengzhou,the south-west of Jiaxian and the west of Yexian;The thickness of the middle and deep water-bearing sand layer is 20~50 m,60~80 m in Kaifeng County,eastern Luohe,Xincai County and Taikang County.(3)The number of water-conducting systems in the study area ranges from 50 m^(2)/d to the upper and lower limits of 200 m^(2)/d,and the number of water-conducting systems in individual prefecture-level counties(such as Kaifeng and Xincai Counties)and municipalities(such as Shangqiu and Luohe)exceeds 300 m^(2)/d,and in some cases,it even exceeds 500 m^(2)/d.The results of the study are of great significance to the mastery of the law of groundwater storage in the eastern plains of Henan Province,the sustainable development and rational use of groundwater resources,so as to achieve the comprehensive development and implementation of scientific and optimal management of water resources.