Magmatic rocks under the plain are closely organized. After the groundwater flows here, it can't flow when it touches magmatic rocks. Magmatic rocks are covered with impermeable clay layers, so groundwater can't freely flow out of the ground. These blocked groundwater, with strong pressure, rushed from underground cracks to the ground, forming these Baotu springs.
Baotu Spring spews 70,000 cubic meters of spring water every day. Baotu spring water gushed from underground limestone cave. There are three outlets in the spring, and the amount of water is huge. The maximum water inflow 1.62 million m/day, and the exposed elevation can reach 26.49 m. The bacterial content of water quality is extremely low, which meets the national drinking water standard after testing.
Extended data:
Geological conditions of Baotu Spring:
The gushing spring of Baotu Spring is related to the topographical structure of Jinan. South of Jinan is mountainous and hilly, with Qianfo Mountain, and north is the Yellow River Plain. Jinan is located at the junction of mountains and plains. The mountainous area of Jinan city is composed of limestone, and magmatic rocks are hidden under the soil of the plain.
Limestone in mountainous areas was formed about 400 million years ago, and its texture is relatively pure. Limestone inclines from south to north with an inclination of about 30. Limestone itself is not very dense, with cracks, cracks and caves, which can store and transport groundwater. Groundwater flows to Jinan along the slope of limestone layer and becomes the source of Jinan spring water.
Baidu Encyclopedia-Baotuquan