Difficulty: Medium
Correct Answer: Monadnock
Explanation:
Introduction / Context:
Landforms created by long term erosion provide valuable clues about the geological history of an area. A peneplain is a nearly level, low relief surface produced by prolonged fluvial erosion. However, some harder rock masses resist erosion and remain standing above this general plain. Such isolated hills have a specific geomorphological name that is important for physical geography and geology examinations. This question checks whether you can correctly identify the technical term for these resistant rock remnants in a river eroded plain or peneplain.
Given Data / Assumptions:
Concept / Approach:
In geomorphology, an isolated hill or knob that rises above a nearly level peneplain due to differential erosion is called a monadnock. This term is widely used in classic geomorphological literature, and such features are often composed of more resistant rock types than the surrounding material. The key to answering this question is to connect the idea of a nearly level erosional surface with differential erosion that leaves behind hard rock masses, and then recall the correct technical name for such remnants. Recognising that other options either refer to different landforms or are not standard terms helps narrow down the choice.
Step-by-Step Solution:
Step 1: Understand that a peneplain is a low relief surface formed after long periods of river erosion.
Step 2: Note that not all rocks erode at the same rate; more resistant rocks can remain as isolated hills.
Step 3: Recall from physical geography that such isolated resistant hills on a peneplain are called monadnocks.
Step 4: Compare this term with the options given, and confirm that Monadnock appears as option A.
Step 5: Select Monadnock as the correct answer because it precisely matches the description in the question.
Verification / Alternative Check:
To verify, you can relate the term monadnock to the famous example of Mount Monadnock in the United States, from which the concept name is derived. Textbooks on geomorphology often use this example to explain how a hard rock mass remains above a peneplain. They also distinguish monadnocks from other features such as inselbergs or tors, which may occur in different climatic and geological settings. Checking multiple geography resources will show that monadnock is consistently defined as an isolated residual hill standing above a low relief erosional surface, confirming that it fits the question accurately.
Why Other Options Are Wrong:
Jukenberg is not a standard term used in mainstream geomorphology for residual hills on a peneplain, and it does not appear in recognised geography texts. The word Hum is sometimes used in karst topography to describe small residual limestone mounds, which is a different context from a broad river eroded peneplain. The option stating that no option is correct is a distractor; since the term monadnock is valid and widely accepted, this statement is not true in this question. Therefore, options B, C and D do not match the precise landform described.
Common Pitfalls:
Students sometimes confuse monadnocks with other residual features such as inselbergs or mesas. Another common error is to assume that unfamiliar sounding terms like Jukenberg must be correct, simply because they look technical. In competitive exams, examiners often include one correct technical term along with plausible sounding but incorrect options. To avoid these mistakes, revise key geomorphological terms from a standard textbook, pay attention to their definitions and typical examples, and practice matching descriptions with names. This strengthens conceptual clarity and reduces guesswork.
Final Answer:
The isolated remains of resistant rocks standing above a river eroded plain or peneplain are called Monadnock, so Monadnock is the correct option.
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