The rocks which are formed due to pouring of magma at the earth's surface are called
🌋 Understanding Magma vs. Lava
The key to this question is knowing the difference between magma and lava, which is all about location.
Magma: This is molten rock that is still inside the Earth.
Lava: This is the term for magma once it has erupted or "poured" onto the Earth's surface.
Therefore, the question is asking for the name of rocks formed from cooling lava.
🔬 Detailed Analysis of the Options
C. Volcanic Rocks
This is the correct answer. Volcanic rocks, also known as extrusive igneous rocks, are formed when lava cools and solidifies on the Earth's surface. Because they are exposed to the relatively cool air or water, they cool very quickly. This rapid cooling prevents the formation of large mineral crystals.
- Formation Location: On the Earth's surface.
- Cooling Rate: Fast.
- Resulting Texture: Fine-grained (crystals are microscopic).
- Example: Basalt, Pumice, Rhyolite.
A. Plutonic Rocks
This is incorrect. Plutonic (or intrusive) rocks are formed when magma cools slowly at great depths *beneath* the Earth's surface. They do not pour out onto the surface.
B. Hypabyssal Rocks
This is incorrect. Hypabyssal rocks are an intermediate type that form at a shallow depth *below* the surface, not on it.
D. Igneous Rocks
This is a broad parent category. While a volcanic rock is a type of igneous rock, "Volcanic rock" is the more specific and therefore better answer to the question, which describes a specific formation environment (the surface).
📊 Quick Comparison of Igneous Rock Types
| Classification | Formation Location | Cooling Rate | Crystal Size | Example |
|---|---|---|---|---|
| Plutonic (Intrusive) | Deep inside Earth | Slow | Large | Granite |
| Hypabyssal | Shallow depth | Medium | Medium | Dolerite |
| Volcanic (Extrusive) | On the surface | Fast | Small | Basalt |
💡 Study Tips
- Volcanic = Volcano: This is the easiest connection. Volcanic rocks come from volcanoes, which erupt lava onto the surface.
- Extrusive = Exit: Volcanic rocks are also called "extrusive" because the lava has "exited" the Earth.
- Surface = Speed: Cooling on the surface is fast, which means small crystals. Cooling deep underground is slow, which means large crystals.