For a man who reached Brazil on a six-month tourist visa 40 years ago, Dr. Valiya M. Hamza has a river named after him in that country.

The ‘Hamza River,’ which he discovered in Brazil’s Amazon region, is the longest underground river running for a length of 6,000 km at a depth of nearly 4 km. It flows all the way from the Andean foothills to the Atlantic coast in a nearly west to east direction like the mighty Amazon river. 

The discovery brought to light the first and geologically unusual instance of a twin-river system flowing at different levels of the earth’s crust in Brazil. 

Dr. Hamza, who is visiting India for the first time after his discovery was made public last year, recounts how he handled both accolades and the brutal criticism he faced about his discovery, including comments published in foreign media such as “the word ‘river’ should be burned from the work – it’s not a river whatsoever.”

The barbs from the scientific community were, however, effectively silenced when the Journal of South American Earth Sciences published his findings on the Hamza River in 2012.

“My journey in Brazil started when a friend invited me over in 1974. I went there as a tourist for six months and stayed on to work for 40 years,” Dr. Hamza, surrounded by family members at his ancestral home in Kozhikode, told The Hindu on Tuesday.

Dr. Hamza recalls how he could have lived a comfortable life as a physics lecturer in Feroke College, Kozhikode.

“But I got an opening as a scientific assistant at the National Geophysical Research Institute in Hyderabad. That changed my life. I found my calling in geophysics — a discipline in which my interest in physics could be used to understand what is going on under the earth,” he said.

After bagging the National Research Council of Canada scholarship and completing his doctorate in 1973, he was looking at job opportunities in Canada.

“But the call from my friend changed everything. When I went to Brazil, I found that it was more challenging as there was very little research being done there. I just packed my equipment and opened a laboratory,” he said.

In 1992, his work with the University of Sao Paulo and researches with the Technology Research Institute in the fields of oil exploration, mineral mining, climate change, and energy got the attention of the Federal Government of Brazil.

“The same year I joined the National Observatory in Rio de Janeiro. The only condition they placed before me was that I should be a Brazilian citizen,” he said.

It was during this time that his student Elizabeth T. Pimentel accessed data on the oil explorations conducted by the Brazilian oil company Petrobras in the Amazon region. He advised her to take it up as her thesis work.

“During our researches we found that Petrobras had recorded subterranean temperature variations. But they had not bothered to analyse the data. They were only interested in oil,” he said. Studies by the duo led to the finding that in the entire area of Amazon, the rocks at a shallow depth of 2,000 to 3,000 metres were cooler than what normally should be.

“The only way to produce that kind of cooling is when there is a sub-surface flow. Our technique and analysis was unique. It was my students who decided to honour me by naming the river after me,” he said.

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