Details about Drainage Pattern
A drainage pattern can be well briefed concerning the topological features from where a stream gets runoff through its flow and the groundwater flow. These flows can be well divided by the watersheds (topological barriers). A watershed is the combined stream tributaries that flow to someplace along the channel of the stream. There are various types of drainage patterns across the world, but in this article, we will focus more on the Trellis Drainage pattern and its various details. The article provided by Vedantu‘s team mainly talks about trellis drainage pattern, trellis geology, examples of trellis drainage pattern, formation and flow in a draw restrain is pattern diagram and actuality, difference between various types of drainage patterns such as rectangle a drainage pattern, trellis drainage pattern, dendritic drainage pattern.
Trellis Drainage Pattern
Also known as the Trellis drainage system or the Trellis River pattern is the one that we can mostly find across the southern regions of a map. Experts define the trellis drainage pattern as the indication of structural control by varying types of eroded and folded sedimentary rocks. Across a humid region, resistant rocks like sandstone from the ridges and the non-resistant ones like shale and limestone form the valleys. Sometimes, there is the occurrence of a dip angle, causing the asymmetric ridges.
Trellis Geology
A Trellis pattern of the river has the same geometry as the standard garden trellis; along a strike valley, smaller tributaries are fed into from the steeper slopes across the mountain's sides. These tributaries then enter into the main river perpendicularly, leading to a trellis-like appearance of the system. Trellis drainage definition states that they form where the hard and soft formations exist on both sides of any river. The formations must also be reflective of height and accentuated by erosion. Trellis drainage pattern is the folded mountains' characteristic, like that of the Appalachian Mountains in Northern America and Northern Trinidad.
(Image will be uploaded soon)
Example of Trellis Drainage Pattern
The streams near the Southeast of Piney Mountain and Little Allegheny Mountain are known to form a trellis stream pattern. Here, the resistant bedrock ridges get drained by the shorter stream, and the non-resistant units form valleys with the subsequent streams. As is expected from a general Trellis drainage pattern definition, the stream locations before exposure of this surface imprint upon the current Pattern. This imprint is then evident in how the streams cut through the ridges.
Formation and Flow in a Trellis Drainage Pattern Diagram and Actuality
By the time the erosion wears away the surface and exposes the folded sedimentary rocks below, the streams stay there. They further continue eroding down, and there they encounter the resistant beds; the streams continue eroding them too. This leads to the formation of newer slopes and streams on the slopes, and these then become the tributaries for the mainstream in the area. The principal streams are superimposed on the current landscape. These landforms where the streams cut through ridges are called the water gaps, and they form with the running water and Fluvial Processes. Streams then continue flowing from higher elevation to lower, down the slope. The stream extends its headwaters and forms tributaries near the source; this process is called Headward Erosion.
Difference Between Trellis and Rectangular Drainage Pattern
Rectangular Drainage Pattern: It is the drainage pattern where the main streams and their tributaries display numerous right-angle bends and exhibit sections of approximately the same length. It indicates the streams that follow prominent faults or the joint systems that break the rocks into rectangular blocks. Various forms of weathering on the joint systems or faults in any bedrock localize the streamflow, leading to the production of a Rectangular pattern. These drainage patterns are developed mainly on firmly joined rocky terrains.
Trellis Drainage System: This type of drainage system occurs when the sub-parallel streams erode a valley across the less resistant formations and sides. These beds are mainly visualized as steeply dipping and might also be a part of a folding system. These tributaries also intersect at right angles where the water gap cuts through some more complex formations. A river joined by the tributaries at approximately right angles develops a Trellis drainage pattern. It is mainly found where the hard and soft rocks exist parallel to one another.
Difference Between Dendritic and Trellis Drainage Pattern
The dendritic drainage pattern develops at the regions where the river channels follow the terrain's slope. Here the mainstream and its tributaries resemble the branches of a tree. In contrast, a Trellis river pattern is formed when a river and its tributaries join at approximately 90-degrees and are found where hard and soft rocks exist parallel to each other.
Trellis drainage pattern is a type of drainage pattern that is taught very briefly in class 11 geography, in chapter 3 called drainage system. This chapter is taught in schools that follow the curriculum set by the Central board of secondary education. The study notes provided by Vedantu on the types of drainage patterns can be studied by class 11 students who are pursuing geography, however, these notes are also useful for UPSC aspirants as geography holds a substantial weightage in the exam held by the UPSC. IAS/IFS aspirants Who want to get a quick revision of the basic concepts covered in geography can refer to these notes provided by Vedantu. As they are written in an extremely simplified language they can help you get ahead of the exam preparation phase.
The study material provided on Vedantu‘s website on the topic of trellis drainage patterns is extremely beneficial as it contains minute details that might be missed by students preparing for an examination. This article mainly covers information on the trial of drainage patterns however there are various drainage patterns that can be studied on Vedantu‘s website. The study material acts as a reference guide and is extremely precise and detailed. Vedantu‘s research team includes many expert geography teachers who are well-versed in the field and therefore they have produced the study notes through extensive research and through the critical analysis of previous year question papers.
FAQs on Trellis Drainage Pattern
1. What exactly is a Trellis Drainage Pattern in Geography?
A Trellis Drainage Pattern is a system where the primary tributary rivers flow parallel to each other, and the secondary tributaries join them at nearly perfect right angles. This creates a distinctive pattern that resembles a garden trellis, which is where it gets its name. It typically develops in regions with folded or tilted rock layers of varying hardness.
2. How does a trellis pattern differ from a dendritic pattern?
The main difference lies in the underlying rock structure and the resulting shape.
- A dendritic pattern looks like the branches of a tree and forms on rock that has uniform resistance to erosion.
- A trellis pattern, on the other hand, is much more structured and grid-like. It forms where there are alternating bands of hard and soft rock, forcing rivers into parallel valleys with tributaries joining at right angles.
3. What kind of geological landscape causes a trellis drainage pattern to form?
This pattern is a direct result of a specific geological landscape, usually one with folded mountains. In these areas, there are long, parallel ridges of hard, resistant rock separated by valleys of softer, less resistant rock. The main rivers carve their channels through the softer rock in the valleys, while shorter tributary streams flow down the steep slopes of the hard ridges, meeting the main river at a right angle.
4. What are the most common types of drainage patterns I should know?
Besides the trellis pattern, a few other common types are important to understand in Geography:
- Dendritic: A tree-branch-like pattern, the most common type.
- Rectangular: Streams meet at right angles, but in a more blocky pattern due to faults in the rock.
- Radial: Streams flow outwards in all directions from a central high point, like a volcano.
- Centripetal: Streams flow inwards from all directions towards a central low point, like a basin or crater.
5. Why do the tributary streams in a trellis system join the main river at a right angle?
The right-angle junctions are a key feature and happen because of the landscape's structure. The main river follows the path of least resistance along the length of a valley (soft rock). The tributary streams flow down the steep, short slopes of the adjacent hard rock ridges. This perpendicular path is the most direct route down the slope, causing them to intersect the main river at or near a 90-degree angle.
6. Can you give a real-world example of where a trellis drainage pattern is found?
A classic example of a trellis drainage pattern can be seen in the Appalachian Mountains of North America. This region consists of long, folded ridges and valleys, creating the perfect conditions for this grid-like river system to develop. In India, parts of the Singhbhum region also exhibit this pattern.
7. Is a rectangular drainage pattern the same as a trellis pattern?
No, they are different, although both feature right-angled junctions. A trellis pattern is controlled by alternating parallel bands of hard and soft rock. In contrast, a rectangular pattern is controlled by a network of faults or joints in the bedrock that are perpendicular to each other. The streams follow these cracks, creating a blocky, rectangular grid rather than a parallel, trellis-like one.
