Artesian Aquifer and Water Pressure

An artesian aquifer is a confined aquifer containing groundwater that is under pressure. The water in an artesian aquifer is usually at an elevated pressure level compared to the surrounding atmosphere. The pressure in the aquifer is caused by the weight of the overlying rock and soil layers.

Water Pressure in Artesian Aquifer

The pressure in an artesian aquifer can be above atmospheric pressure, which is the pressure exerted by the weight of the Earth's atmosphere. This is because the water in the aquifer is confined by layers of impermeable rock or clay that prevent the water from flowing freely. As a result, the water in the aquifer is under pressure and can rise to the surface through a well or spring.

Options Explanation

Option 'A' is incorrect because the water in an artesian aquifer is not at sub-atmospheric pressure. Sub-atmospheric pressure means that the pressure is less than atmospheric pressure, which is not the case in an artesian aquifer.

Option 'B' is incorrect because the water in an artesian aquifer is not at atmospheric pressure. As explained earlier, the water in the aquifer is under pressure and can rise to the surface through a well or spring.

Option 'C' is incorrect because the water in an artesian aquifer is not at 0.5 times atmospheric pressure. The pressure in an artesian aquifer can vary depending on the depth of the aquifer and the weight of the overlying layers.

Option 'D' is correct because the water in an artesian aquifer is usually above atmospheric pressure. This is because the water in the aquifer is confined by impermeable layers of rock or clay, which creates a pressure gradient that causes the water to rise to the surface through a well or spring.

Artesian aquifer is type of aquifer in which when we go down (dig) to that aquifer the water comes out with a very high pressure so the option d is correct.

if the pressure is bellow atm pressure then there is a vaccum pressure is created and this is not the condition of artesian aquifer.