Characteristics and formation mechanisms of spring systems in Laiwu Region

Abstract

[Objective] Numerous springs emerge in the Laiwu region, yet no systematic research has been conducted. To clarify the spring characteristics, spring systems, and their formation mechanisms in this region, and to support spring protection efforts, a systematic investigation was conducted based on the spring survey in Laiwu. [Methods] Method including data utilization analysis, hydrogeological surveys, geological drilling, and water quality analysis were employed to analyze the hydrogeological conditions for spring development. The distribution, hydrochemical, and quality characteristics of the springs were summarized. The spring systems were classified, and the formation mechanisms and controlling factors were examined. [Results] The result showed that the springs were mainly distributed at the margins of Laiwu Basin and in river valleys. Based on aquifer lithology, they could be classified into karst springs and fissure springs, with descending springs being dominant and a few ascending ones. The main hydrochemical types included HCO₃-Ca, HCO₃-Ca·Mg, and HCO₃·SO₃-Ca, with major ions primarily derived from water-rock interactions. 82% of the springs met or exceeded the Class III groundwater quality standards, with some being strontium-type or metasilicic acid-type natural mineral water. Spring formation was controlled by geological factors such as topography, stratum lithology, and fault structures, mainly featuring shallow circulation with rapid water cycling. [Conclusion] The spatial distribution of springs in the Laiwu Region is significantly affected by topographic variations. The springs show overall good water quality with rapid circulation. The spring discharge shows strong correlation with precipitation, making it susceptible to human activities. The systematic analysis of the spring systems in Laiwu provides technical support for the coordinated development of spring protection and urban planning in the region.

Keywords

spring system / formation mechanism / hydrogeology / Laiwu,Shandong Province / influencing factors