I. Bedrock fissure water
Bedrock fissure water is widely distributed in the low mountains and hills around
the basin. The project site is dominated by bedrock fissure water, which is mainly
recharged by vertical infiltration of atmospheric precipitation. The water environment alternates strongly and water discharges to the nearby valleys, basically from
the mountain to the basin, and overflows the surface in the form of springs at
favorable terrain positions. In the wet season, groundwater is recharged by surface
water. In the dry season, surface water is recharged by groundwater.
The dynamic state of groundwater level is affected by precipitation, and the
spring flow variation in the wet and dry seasons can be about 10 times or more.
Moreover, the annual decreasing amplitude is closely related to rainfall intensity
and its duration. Generally speaking, the groundwater level rises in the seasons of
relatively abundant atmospheric precipitation from March to August, and slowly
drops from September to February of the following year, with the water level
varying between 0.5 and 4.5 m and exceeding 8.5 m in some places.
II. Weathered eluvial pore-fissure water
Weathered eluvial pore-fissure water is mainly distributed in the hilly gentle slope
around the basin of A city in a province in Southeast China, and mainly receives
vertical infiltration recharge of atmospheric precipitation and lateral recharge of
bedrock fissure water, and some surface water recharge as its watershed is the same
as that of bedrock fissure water. The groundwater flows in adjacent low-lying
valleys and discharges out of the surface in the form of springs. Since the weathered
elluvium in the area is mostly developed in the surface layer, the lithology is
dominated by eluvial cohesive soil and sandy cohesive soil, with fast groundwater
recharge, short runoff path, fast discharge, and obvious dynamic change with the
season. According to the regional hydrogeological survey report of 1: 200,000, the
annual variation amplitude of water level is 1.34–5.34 m, groundwater is recharged
by surface water in the wet season, while surface water is recharged by groundwater
in the dry season. In addition, evaporation is also an important way of discharge.
III. Quaternary loose rock fissure water
Quaternary loose rock pore water is mainly distributed in A city basin and intermountain basins in a province in Southeast China, and mainly receives recharge of
atmospheric precipitation and surface water. The main way of discharge is subsurface runoff, followed by artificial mining and evaporation, which is a mining
meteorological type. Annual variation amplitude is closely related to rainfall
intensity and duration. Due to the lagging effect of groundwater, the water level
generally rises 1–3 days after the rain. Normally, March–August is the wet season
when the groundwater level rises. The groundwater level drops slowly in the dry
season from September to February of the following year. The groundwater
recharge is greatly affected by the season. In the wet season, groundwater is
recharged by surface water, while in the dry season, surface water is recharged by
groundwater.
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Bedrock fissure water is widely distributed in the low mountains and hills around
the basin. The project site is dominated by bedrock fissure water, which is mainly
recharged by vertical infiltration of atmospheric precipitation. The water environment alternates strongly and water discharges to the nearby valleys, basically from
the mountain to the basin, and overflows the surface in the form of springs at
favorable terrain positions. In the wet season, groundwater is recharged by surface
water. In the dry season, surface water is recharged by groundwater.
The dynamic state of groundwater level is affected by precipitation, and the
spring flow variation in the wet and dry seasons can be about 10 times or more.
Moreover, the annual decreasing amplitude is closely related to rainfall intensity
and its duration. Generally speaking, the groundwater level rises in the seasons of
relatively abundant atmospheric precipitation from March to August, and slowly
drops from September to February of the following year, with the water level
varying between 0.5 and 4.5 m and exceeding 8.5 m in some places.
II. Weathered eluvial pore-fissure water
Weathered eluvial pore-fissure water is mainly distributed in the hilly gentle slope
around the basin of A city in a province in Southeast China, and mainly receives
vertical infiltration recharge of atmospheric precipitation and lateral recharge of
bedrock fissure water, and some surface water recharge as its watershed is the same
as that of bedrock fissure water. The groundwater flows in adjacent low-lying
valleys and discharges out of the surface in the form of springs. Since the weathered
elluvium in the area is mostly developed in the surface layer, the lithology is
dominated by eluvial cohesive soil and sandy cohesive soil, with fast groundwater
recharge, short runoff path, fast discharge, and obvious dynamic change with the
season. According to the regional hydrogeological survey report of 1: 200,000, the
annual variation amplitude of water level is 1.34–5.34 m, groundwater is recharged
by surface water in the wet season, while surface water is recharged by groundwater
in the dry season. In addition, evaporation is also an important way of discharge.
III. Quaternary loose rock fissure water
Quaternary loose rock pore water is mainly distributed in A city basin and intermountain basins in a province in Southeast China, and mainly receives recharge of
atmospheric precipitation and surface water. The main way of discharge is subsurface runoff, followed by artificial mining and evaporation, which is a mining
meteorological type. Annual variation amplitude is closely related to rainfall
intensity and duration. Due to the lagging effect of groundwater, the water level
generally rises 1–3 days after the rain. Normally, March–August is the wet season
when the groundwater level rises. The groundwater level drops slowly in the dry
season from September to February of the following year. The groundwater
recharge is greatly affected by the season. In the wet season, groundwater is
recharged by surface water, while in the dry season, surface water is recharged by
groundwater.
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231