山东鲁西北地区东营组砂岩热储及流体化学特征

Characteristics of Sand Geothermal Reservoir and Fluid Chemical Characteristics of Dongying Formation in Northwestern Shandong Province

鲁西北地热区莫霍面埋藏较浅,具有较高的热流值和富水性较强的含水层,是山东省地热资源开发潜力最大的地区,热储主要为层状热储,地温相对于其它地热区均匀。鲁西北地区东营组主要发育泥岩、细砾岩、砂岩等,沉积厚度受基底起伏和区域构造的控制。研究表明,鲁西北地区东营组砂岩热储表现为自西向东、自南向北变厚趋势;鲁西北地区东营组砂岩热储为细粒砂岩、砂砾岩,总的分布规律是在坳陷、凹陷的中心厚度最大,在盆地边缘最薄,分布不稳定。区内东营组热储补给微弱,为难再生资源,水中阴离子以Cl^(-)为主,阳离子以Na^(+)为主,水化学类型为Cl—Na型。

Moho surface in the geothermal area of northwestern Shandong is shallowly buried,with high heat flow value and strong water-rich aquifer.It is the area with the greatest potential for geothermal resource development in Shandong Province.The thermal reservoir is mainly a layered thermal reservoir,and the ground temperature is relatively uniform compared with other geothermal areas.The Dongying Formation in northwestern Shandong mainly develops mudstone,fine conglomerate,sandstone.The sedimentary thickness is controlled by basement undulation and regional structure.The research shows that the geothermal reservoir sand layer of Dongying Formation in northwestern Shandong shows a thickening trend from west to east and from south to north;The geothermal reservoir sand layer of Dongying Formation in northwestern Shandong is fine sandstone and sandy conglomerates,the general distribution law is that the thickness is the largest in the center of the depression,the thinnest in the edge of the basin,and the distribution is unstable.The thermal reservoir recharge of Dongying Formation in the area is weak,which is hard renewable resource,the anions in the water are mainly Cl^(-),the cations are mainly Na^(+),and the hydrochemical type is a Cl-Na type.