Deccan Plateau

Long ago, lava poured out of long cracks in the ground, again and again.

Each flow cooled into a layer of dark rock. The layers piled up very high.

IUGS explains that each Deccan lava flow came from a long crack, or fissure, like the eruptions in Hawaii and Iceland today but vastly larger. Flow after flow piled up. Near the town of Mahabaleshwar in the Western Ghats, about 50 flows are stacked in a pile about 1,200 meters thick.

India was once part of Gondwanaland, an ancient supercontinent that began breaking apart about 150 million years ago, according to the OneEarth ecoregion profile.

IUGS describes each flow as a dyke-fed fissure eruption, similar to but vastly larger than modern Hawaiian and Icelandic eruptions, with individual eruptions of about 1,000 km³. The preserved basalt is about 2 km thick in the Western Ghats escarpment; at Mahabaleshwar, about 50 flows form a sequence about 1,200 m thick, capped by a ferricrete crust from later weathering. Parts of the province were down-faulted into the Arabian Sea during India-Seychelles rifting about 62.5 million years ago.

Research on the Traps goes back to about the 1830s, much of the early work by the Geological Survey of India.

The lava flows happened around the time the dinosaurs died out.

Scientists are still working out how much the lava had to do with it.

The Deccan eruptions happened close to the time, 66 million years ago, when an asteroid hit Earth and the dinosaurs died out. IUGS says Deccan volcanism, which released huge amounts of gas, played a critical role in that mass extinction.

Other scientists are less sure. A team at the University of California, Berkeley, suggested in 2015 that the asteroid impact may have set off the biggest Deccan eruptions, but said it was still unclear whether the lava helped kill the dinosaurs.

IUGS states that single Deccan eruptions of about 1,000 km³ each released about 10 gigatons of carbon dioxide and sulfur dioxide, and that Deccan volcanism played a critical role in the Cretaceous-Paleogene mass extinction.

A 2015 UC Berkeley study (Richards and colleagues, GSA Bulletin) argued that the impact 66 million years ago probably triggered most of the immense Deccan eruptions, since the impact fell within about 100,000 years of the largest flows; team leader Mark Richards said it was still unclear whether the lava contributed to the extinction. The question remains open.

In the driest parts, thorny bushes and trees grow low and far apart.

Antelopes, deer and foxes live there.

In the arid parts of the plateau grows thorn scrub: low, sparse, thorny trees and bushes, mostly acacias. OneEarth says less than 750 millimeters of rain falls in a year, almost all from May to October.

The scrub is home to the Jerdon's courser, a ground-dwelling bird that is active at night. It was thought to be extinct until it was found again in 1986, after no sightings since 1900. Blackbuck, four-horned antelope and Indian foxes live there too.

The OneEarth profile of the Deccan Thorn Scrub Forests ecoregion describes low, sparse thorn scrub dominated by Acacia, grading into Euphorbia scrub where rainfall is lower and rocky ground is exposed; open canopies let grasses grow, supporting grassland birds such as the Indian bustard, lesser florican and Jerdon's courser, and mammals from the four-horned antelope and blackbuck to nilgai and gaur.

The nocturnal Jerdon's courser, described in 1848, was assumed extinct until its 1986 rediscovery; the ecoregion holds its only population. OneEarth adds that most natural habitat has been degraded or cleared, and only about 1% of the ecoregion is protected.

Summers on the plateau can be very hot. Children get sick from heat more easily than grown-ups.

On hot days, stay close to your grown-up.

OneEarth notes that summer temperatures in the plateau's dry scrub can go above 40 °C. The US National Weather Service says young children and babies are especially at risk from heat-related illness, because their bodies are less able to adapt to heat than adults' bodies.

OneEarth notes that almost all the rain falls between May and October.

In the arid Deccan, OneEarth gives summer temperatures that can exceed 40 °C. The US National Weather Service notes that young children and infants are particularly vulnerable to heat-related illness because their bodies are less able to adapt to heat than adults'.

On the Western Ghats edge, the Mahabaleshwar section is, IUGS notes, a popular destination visited by hundreds of thousands of tourists a year for its pleasant climate and scenery.