EARTH SCIENCE
GROUNDWATER
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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when artificial ponds are created
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when topsoil vegetation increases
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when the top soil layers become more porous
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when the water table intersects with the surface of the soil
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Detailed explanation-1: -1. Figure 12.9 and 12.12: A spring is a natural flow of water that occurs when the groundwater table intersects the land surface. The water emerges at the ground surface.
Detailed explanation-2: -Once it reaches the zone of saturation under the ground, groundwater begins to move slowly by the force of gravity through the interconnecting pore spaces until it reaches a discharge area, where it seeps or flows out into a wetland, spring, river, or pond to become part of the surface water.
Detailed explanation-3: -Springs are formed where the water table naturally meets the land surface, causing groundwater to flow from the surface and eventually into a stream, river, or lake. The water table level can vary in different areas and even within the same area.
Detailed explanation-4: -Depression springs are formed in unconfined aquifers when the topography intersects the water table, usually due to the surface stream incision.
Detailed explanation-5: -The time it takes for surface infiltration to reach an aquifer as deep as 400 feet may take hours, days, or even years, depending on the rate of recharge. In some of the flood-irrigated areas, groundwater levels in nearby domestic wells rise within a few hours to days of flood-up.