The igneous body with dome or mushroom-like shape is known as a
Show Hint
- lopolith
- ring dike
- sill
- laccolith
The Correct Option is A
Solution and Explanation
Igneous intrusions are classified based on their geometry and relation to surrounding rock layers. A laccolith is a concordant intrusive body that has a flat base and a domed top, resembling a mushroom shape.
Step 2: Comparing the options.
(A) Lopolith: Large, saucer-shaped intrusion that is concave upward.
(B) Ring dike: Circular or arcuate intrusion formed along ring fractures.
(C) Sill: Tabular, concordant intrusion parallel to bedding planes.
(D) Laccolith: Concordant intrusion with a flat base and dome-shaped top, formed when magma uplifts overlying strata — mushroom-like in shape.
Step 3: Conclusion.
The correct answer is (D) Laccolith.
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