Erosion and Deposition : Action of Running Water and Groundwater

Even if we are taking into account the processes of erosion and deposition as well as the landforms that they produce, it is important to remember that these processes are invariably assisted by weathering as well as mass movements. There are a number of other factors that have an independent impact on the development of these landforms. Some of these factors include: (I) the consistency of the sea level; (ii) the tectonic stability of the continent; and (iii) the climate.

What Does Running Water Do?

Running water, which doesn’t require any further explanation, has two components: the first is overland flow over the general land surface as a sheet, and the second is linear flow as streams and rivers in valleys. Neither of these components can be separated from the other.

Sheet erosion is caused by the overland flow, and depending on the irregularities of the ground surface, the overland flow can either concentrate into narrow or wide channels.

During the process of sheet erosion, a minute or significant quantities of material are eroded from the surface of the land along the direction of flow, and gradual rolls that are small and narrow will form over time.

These rills will eventually transform into gullies that are quite extensive and lengthy, and those gullies will continue to get deeper, wider, and longer before joining together to form a network of valleys. (It should be noted that a valley can be generated via a variety of processes, such as faulting; however, in this context, we will only be discussing the formation via an exogenous geomorphic agent.)

After the formation of a valley, a stream or river will eventually make its way through the valley.

The paths that a river takes.

On the basis of its route, a river, which is the best illustration of the linear flow of rushing water through a valley, can be split into three parts: an upper course, a middle course, and a lower course.

Upper Course / Stage of Youth (Erosion predominates): Upper Course / Stage of Youth:

It begins at the headwaters of the river, which are located in mountainous or hilly terrain.

As a result of the river’s flow down the steep slope, both its speed and its ability to erode the landscape are at their highest levels.

There aren’t many streams, and the integration isn’t great.

Because of the rapid descent of the river, there will be a significant amount of vertical erosion or downward cutting, which will lead to the construction of valleys in the shape of a V.

Falls, rapids, and gorges can be found in areas where the underlying hard rock bodies of the area are exposed.

Middle Course/Stage of Maturity (Transportation Dominates)

During this stage, vertical erosion starts to be replaced by lateral erosion or erosion from both sides of the channel. This occurs because transportation is the dominant force in this stage.

As a result, the river channel is responsible for the slow erosion of the valley’s distinctive V shape (not completely).

At this time, there are lots of streams, all of which have good integration.

In this section, the flood plains start to become more expansive, and the amount of water rises as a result of the convergence of a number of smaller streams.

Transportation of eroded materials from the upper course constitutes the vast majority of the river’s work (little deposition too).

At this stage, various landforms can be observed, including alluvial fans, piedmont alluvial plains, meanders, and so on.

The river begins to flow over a vast, level plain with heavy debris brought down from the higher and middle courses as it enters the lower course, also known as the stage of old.

Although vertical erosion has nearly come to a halt, lateral erosion is still taking place.

The river does much of its work by depositing sediment, which adds to the bed it travels on and creates an expansive flood plain.

At this stage, various landforms can be observed, including braided channels, floodplains, levees, meanders, oxbow lakes, and deltas, among others.

Conclusion 

Running water has two components: overland flow over the general land surface as a sheet, and linear flow as streams and rivers in valleys. During the process of sheet erosion, a minute or significant quantity of material is eroded from the surface of the land along the direction of flow. During this stage, transportation is the dominant force in the river’s development. Falls, rapids, and gorges can be found in areas where the underlying hard rock bodies are exposed. The river begins to flow over a vast, level plain with heavy debris brought down from the higher and middle courses.

What exactly is the function of groundwater?

Underground water, often known as groundwater, is the term given to the portion of the water that results from precipitation or snowmelt that seeps through the surface and collects in the rocks below.

The rocks that enable water to easily pass through them are referred to as permeable rocks, whereas the rocks that do not allow water to pass through them are referred to as impermeable rocks.

After travelling downwards to a certain depth, the groundwater then flows horizontally via the bedding planes, joints, or the materials themselves. This occurs after the water has travelled downwards for some distance.

The amount of groundwater present varies considerably from one location to the next; yet, the role that groundwater plays in sculpting the surface characteristics of the earth is fairly significant.

The effects of groundwater are most readily observed in rocks that are high in calcium carbonates, such as limestone, gypsum, or dolomite. Other examples include:

Karst topography refers to the characteristic landforms that are produced by the action of groundwater through the processes of solution and deposition in the Karst region of the Balkans. The zones or horizons of permeable and porous rocks that are completely filled with water are referred to as the Zones of Saturation.

The markings that show the upper surface of these saturated zones of the groundwater are referred to as water tables, and they are located in the earth.