Deccan Traps

Long ago, hot lava flowed in India.

This lava made many big layers of rock. These rocks look like giant stairs.

This place is called the Deccan Traps. It is a very large area. The name Deccan means "southern."

The lava could have changed the air. This might have made the world cooler. Some people think this happened when dinosaurs lived. It is a very amazing place to study.

The Deccan Traps are a giant area of rock in India.

They were made by many huge volcanic eruptions. These eruptions happened a long time ago. They took place between 66.3 and 65.6 million years ago.

This was near the time when dinosaurs went extinct.

The rocks look like big steps. This is because the word "trap" comes from a Swedish word for stairs. The lava flowed out in many layers. Most of this lava is a dark rock called basalt.

Scientists think a hotspot caused the eruptions. A hotspot is a place where hot rock rises from deep inside the Earth. This hotspot is called the Réunion hotspot. It is still active today near the Mascarene Islands.

Some scientists think the volcanic gases changed the climate. These gases might have made the Earth cooler for a short time. However, most experts believe a space rock hit the Earth first. This impact was the main cause of the mass extinction. The Deccan Traps may have played a small part in the changes.

The Deccan Traps are one of the largest volcanic features on Earth.

This huge area is located in west-central India. It is made of many thick layers of solidified lava. These layers are mostly a dark rock called basalt.

The word "trap" comes from a Swedish word for stairs. This is because the hills in the region look like giant steps. The name "Deccan" comes from a Sanskrit word meaning "southern."

These massive eruptions happened through a process called fissure eruptions. Instead of one mountain, lava flowed out of long cracks in the ground. This lava piled up in many different layers over a long time.

Scientists believe a deep mantle plume caused this. A mantle plume is a hotspot of hot rock rising from deep inside the Earth. This specific hotspot is called the Réunion hotspot. It is still active today near the Mascarene Islands in the Indian Ocean. This plume may have even helped pull India away from Africa.

Scientists have studied these rocks to find out when they formed. The eruptions took place between 66.3 and 65.6 million years ago.

This was during the Cretaceous–Paleogene boundary. Most of the volcanic activity happened at the Western Ghats. The eruptions lasted for a very long time, perhaps 600,000 to 800,000 years. Some parts of the eruptions might have even finished in less than 30,000 years. It is hard to find the exact dates because the events happened so quickly.

There is a big debate about how these eruptions affected life on Earth. Some scholars thought the volcanic gases caused a mass extinction. These gases, like sulfur dioxide, might have changed the climate.

One study showed a temperature drop of about 5°C for less than 10,000 years. However, most scientists now believe a space rock impact was the main cause. This impact in North America likely caused an "impact winter." The Deccan Traps may have only played a small role in the extinction.

Even though the volcanoes were huge, they left behind many treasures. Scientists have found many fossils between the layers of lava.

These include ancient freshwater molluscs and even early types of frogs. One well-known frog is called Oxyglossus pusillus. These fossils help us see what lived in India millions of years ago. The rocks tell a story of a changing world. They show us how heat and movement shape our planet.

The Deccan Traps are a massive igneous province located in west-central India.

This feature is one of the largest volcanic structures on our planet. It consists of many thick layers of solidified flood basalt. These layers were created by lava flowing from multiple volcanic centers. The total volume of these rocks is approximately 500,000 cubic kilometers. Originally, the lava may have covered an area as large as 1.5 million square kilometers. This would be about half the size of modern India.

Today, the visible area is smaller due to erosion and plate tectonics.

Geologists believe these eruptions were caused by a deep mantle plume. A mantle plume is a rising column of hot rock from deep inside the Earth. This specific plume is known as the Réunion hotspot. This hotspot is still active today near the Mascarene Islands in the Indian Ocean. The plume likely caused the eruptions and helped pull India away from Africa. This process is called rifting, where the Earth's crust pulls apart. As the Indian plate moved north over the plume, massive amounts of magma reached the surface.

This movement is supported by data showing rapid plate motion during the eruptions.

Most of the lava arrived through a process called fissure eruptions. Instead of erupting from a single mountain peak, the lava flowed out of long cracks in the ground. These eruptions occurred over a period of 600,000 to 800,000 years. Most of the activity happened between 66.3 and 65.6 million years ago. This timeframe spans the Cretaceous–Paleogene boundary, a major turning point in Earth's history. Some scientists believe a major pulse of these eruptions lasted less than 30,000 years. However, dating these exact moments is difficult because the transitions happened so quickly.

The province is divided into several distinct parts and layers. Geographically, it includes the main Deccan, the Malwa Plateau, the Mandla Lobe, and the Saurashtran Plateau. Scientists also group the rocks into three stratigraphic units: the Upper, Middle, and Lower traps. These groups are thought to relate to the distance from the original eruption sites. Chemically, the province can be split into as many as eleven different formations. About 95% of the lava is made of tholeiitic basalt. This rock contains minerals like olivine, pyroxenes, and plagioclase.

There is a famous scientific debate regarding the Deccan Traps and the mass extinction of dinosaurs. Some researchers, such as Gerta Keller, suggested volcanic gases caused the extinction. Gases like sulfur dioxide can change the climate by blocking sunlight. One study found that these gases might have caused a temperature drop of 5°C for 10,000 years. However, most scientists now believe the Chicxulub impact in North America was the primary cause. This impact created an "impact winter" that killed many living things. Some studies suggest the Deccan eruptions may have actually helped negate some impact effects.

Despite the massive volcanic activity, the layers of rock have preserved many fossils. These fossils are often found in the Intertrappean Beds between layers of lava. Scientists have discovered ancient freshwater molluscs and early ancestors of modern frogs. One notable species is the toothed frog, known as Indobatrachus. Another famous fossil is the frog Oxyglossus pusillus. These biological remains provide a window into the life of the Late Cretaceous period.

They show how life survived or changed during these intense geological events.

The study of the Deccan Traps connects many different scientific fields. It links geology with biology through the study of fossils. It also connects plate tectonics with climate science. By studying the chemical signatures in the basalt, scientists learn about the deep mantle. The movement of the Indian and African plates helps us understand how continents move. Even the name of the region tells a story of its history. "Deccan" comes from the Sanskrit word for "southern," while "trap" comes from the Swedish word for "stairs."

This is because the layered hills look like giant stone steps.