Karst Landscapes
1. Introduction
The word ‘Karst’ comes from the Krs Plateau in Slovenia, where karst environments were first studied closely. The Slav people use ‘Krs’ to refere to ‘bare stony ground’. More specifically geomorphology refers to karst as a type of terrain characterised mainly by caves, sinkholes and complex drainage networks. The majority of karst formations occur in soluble rocks such as limestone and dolomite (although recent discoveries have revealed karst formations in more resistant rocks such as quartz, but are rare) and the reason for this is connected to the underlying processes. The two chief processes responsible for the weathering of rocks are physical weathering and chemical weathering, but it chemical weathering that is particularly present in soluble rocks (Christopherson 2012).
Around 25% of the earth’s surface is composed of limestone and almost 15% of the earth’s surface contains karst features. Considering the potential hazards of karst features together with their significant proportions it is no surprise that karst environments are highly studied. These hazards include sinkholes, sinkhole flooding and the contamination of groundwater. This essay will also discuss the impact humans have had on karst landscapes.
Figure 1: Karst landscapes and limestone regions (Christopherson 2012)
2. Karst Processes
2.1 Brief Description
The hydrological cycle is very important in the process of karst formations. The formation of karst starts with precipitation that often reacts to carbon dioxide to form carbonic acid. When the water reaches the earth it percolates through very permeable limestone. The water will erode the limestone along cracks and over long periods of time these cracks increase in size to form caves and other karst features.
In many instances tectonic processes are responsible for the exposure of limestone. As uplift takes place and as the limestone starts bulging cracks start to appear making the rock more vulnerable to erosion along
The word ‘Karst’ comes from the Krs Plateau in Slovenia, where karst environments were first studied closely. The Slav people use ‘Krs’ to refere to ‘bare stony ground’. More specifically geomorphology refers to karst as a type of terrain characterised mainly by caves, sinkholes and complex drainage networks. The majority of karst formations occur in soluble rocks such as limestone and dolomite (although recent discoveries have revealed karst formations in more resistant rocks such as quartz, but are rare) and the reason for this is connected to the underlying processes. The two chief processes responsible for the weathering of rocks are physical weathering and chemical weathering, but it chemical weathering that is particularly present in soluble rocks (Christopherson 2012).
Around 25% of the earth’s surface is composed of limestone and almost 15% of the earth’s surface contains karst features. Considering the potential hazards of karst features together with their significant proportions it is no surprise that karst environments are highly studied. These hazards include sinkholes, sinkhole flooding and the contamination of groundwater. This essay will also discuss the impact humans have had on karst landscapes.
Figure 1: Karst landscapes and limestone regions (Christopherson 2012)
2. Karst Processes
2.1 Brief Description
The hydrological cycle is very important in the process of karst formations. The formation of karst starts with precipitation that often reacts to carbon dioxide to form carbonic acid. When the water reaches the earth it percolates through very permeable limestone. The water will erode the limestone along cracks and over long periods of time these cracks increase in size to form caves and other karst features.
In many instances tectonic processes are responsible for the exposure of limestone. As uplift takes place and as the limestone starts bulging cracks start to appear making the rock more vulnerable to erosion along
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