LAKE BARREALES, Argentina — As Jorge Calvo strode along the dusty banks of this Patagonian lake, he scanned the reddish dirt, pointing to the remains of a dinosaur in the desert sun.
Continuing on, he scampered down into an eight-foot pit and waved to Marcela Milani, a technician working with a thick nail and a hammer. She was chipping away at a rock looking for a missing hip bone believed to be part of Mr. Calvo’s most famous discovery, Futalognkosaurus, a new genus of plant-eating dinosaur more than 100 feet long from tail to nose. It is one of the three biggest dinosaurs ever found.
“That one lived nearly 90 million years ago,” said Mr. Calvo, an Argentine geologist and paleontologist. “We are full of dinosaurs here. If you walk, you will find something.”
Mr. Calvo, 46, has his office here, at a year-round excavation of fossils from this vast dinosaur graveyard. He is not pursuing the traditional academic path of paleontologists, collecting in the field for distant museums. After discovering the Futalognkosaurus bones in 2000, he set up shop here two years later along this placid artificial lake lined on one side by deep red rock formations that look strikingly similar to those in Sedona, Ariz.
Mr. Calvo’s Dino Project, about 55 miles north of the city of Neuquén, consists of a handful of trailers with portable bathrooms and a flimsily constructed museum without air-conditioning or flooring where he displays his growing supply of fossils. The operation exists mainly on donations from local energy companies, which are drilling for natural gas in the area.
Mr. Calvo, nevertheless, has been able to attract 10,000 tourists a year from all over the globe, including stressed-out businessmen who come for “therapy” to search for fossils. He spends four days a week in Barreales, sometimes searching for stars at night with his son Santiago, 11. In the summer here, December to March, Mr. Calvo often works with visiting paleontologists from Brazil and Italy. He still teaches geology and engineering at the National University of Comahue in Neuquén, where a birdlike dinosaur he found on campus was named after him.
His approach to paleontology is somewhat controversial. Rodolfo Coria, a paleontologist at the Carmen Funes Museum near Neuquén, said the fossils Mr. Calvo was extracting at Barreales were “hostages” and should be in a proper museum. “I don’t agree with using those fossils in a tourist project,” Mr. Coria said.
The Patagonian region of Argentina, where Mr. Calvo has worked for 20 years, has become one of the most active areas of exploration for dinosaur fossils in the world, along with the Gobi Desert in China and the fossil-rich American West. Paleontologists from around the world have been drawn to work in Patagonia. Argentine scientists have unearthed the largest plant-eating dinosaur, the Argentinosaurus, and the largest carnivore, the Giganotosaurus carolinii, which at about 42 feet long was slightly longer and about three tons heavier than the famed Tyrannosaurus Rex found in the United States.
“Argentina has the richest and longest-term record for dinosaurs in all of the Southern Hemisphere, a record from the first to the last dinosaurs,” said James I. Kirkland, a state paleontologist with the Utah Geological Survey. That record, spanning about 150 million years, is also distinct from that of the Northern Hemisphere, he said, because during the Jurassic period and most of the Cretaceous the continents were breaking up, separating the Northern and Southern Hemispheres. Distinct types of dinosaurs evolved in each region. But around 70 million years ago, just 5 million years before dinosaurs became extinct, a land bridge formed that allowed some dinosaurs from each hemisphere to cross over.
Fossils of dinosaurs from the Cretaceous period (145 to 65 million years ago) have been quite prevalent around Neuquén. “We call it Cretaceous Park,” Mr. Calvo said of the dinosaur graveyard, which includes Lake Barreales.
The country’s first dinosaur fossils were discovered near Neuquén in 1882. For decades museums in Buenos Aires and La Plata, close to the capital, seemed to scoop up all the region’s fossils. The building of regional museums around Neuquén the past two decades has helped keep the fossils at home and has created a sort of dino-tourism.
Some have taken the newfound regionalism to extremes. Ruben Carolini, the head of the dinosaur museum in El Chocón, near Neuquén, was reported to have chained himself to the fossilized skeleton of the Giganotosaurus in 2006 to demand that fossils and replicas sent to Buenos Aires and overseas be returned to his institution. After several hours, he unchained himself after the reconstructed skull of the meat-eater, which had been headed to Buenos Aires, was returned to El Chocón.
Before he was a museum director, Mr. Carolini was an auto mechanic and dinosaur-hunting hobbyist who drove a dune buggy and wore an Indiana Jones hat. He became famous in 1993 for his discovery of a leg bone of the Giganotosaurus, captivating the area and drew international attention.
For his part, Mr. Calvo dreams of turning his isolated spot into an even bigger tourism destination. He showed off a scale model of a $2 million paleontology museum that would have a tunnel blasted through the red-rock mountain leading to a section devoted to the history of the native Mapuche Indians.
“I could search for dinosaur bones for all my life and two more lifetimes and still not be done,” he said. “One thing we have here is time.”