Deccan Traps are a large igneous province located in India and are believed to have formed through massive volcanic eruptions. The eruptions occurred over a period of millions of years, resulting in thick layers of lava and volcanic ash covering an area of around 500,000 square kilometers. The type of eruption that caused the Deccan Traps is a flood volcanic eruption.

Flood Volcanic Eruption:
A flood volcanic eruption is characterized by the outpouring of large volumes of basaltic lava from fissure vents. The lava flows are typically very fluid and can travel long distances before solidifying. The eruption is not explosive and does not result in the formation of a volcanic cone or crater. Instead, the lava flows out in a thin sheet-like manner, covering a large area.

The Deccan Traps Formation:
The Deccan Traps were formed during the late Cretaceous period, around 66 million years ago. The flood volcanic eruptions that created the Deccan Traps were likely caused by the Indian Plate moving over a hotspot in the Earth's mantle. The hotspot caused melting in the mantle, and the resulting magma rose to the surface, causing the massive lava flows.

Conclusion:
In summary, the Deccan Traps were formed through a series of flood volcanic eruptions that occurred over millions of years. These eruptions resulted in the outpouring of large volumes of basaltic lava, covering an area of around 500,000 square kilometers. The type of eruption that caused the Deccan Traps is a flood volcanic eruption.

Deccan trap/peninsular plateau is also an example of Shield Volcanic eruption.