One of the worst earthquakes to hit north-east Italy in hundreds of years rattled the region around Bologna early on Sunday, killing at least four people, collapsing factories and sending residents running out into the streets, emergency services said.

Thousands of residents have been asked for their views on a waste facility sited under the wetlands

Controversial "fracking" for shale gas should only take place at least 600 metres down from aquifers used for water supplies, scientists said today.

A strong earthquake struck off the coast of Mexico today.

Marina Salye was a geologist of considerable repute, locating mineral deposits in the furthest and least hospitable reaches of the Soviet Union and producing dozens of academic papers and six monographs. But she came to prominence as a pugnacious and eloquent leader of the perestroika-era democratic movement in Leningrad, and as a sharp critic of Vladimir Putin ever since she uncovered gross financial malpractice in his St Petersburg office in the early 1990s.

A scientific study in Poland has found that shale gas extraction at one site produced some toxic refuse but that the waste was reused and didn't harm the environment.

Senegal is set for a run-off vote after its aged president failed to win a majority in a contentious election that has threatened to destabilise the West African nation. Former prime minister Macky Sall came a close second to the 85 year old Abdoulaye Wade, according to provisional results, and electors will now have to choose between them in a second round expected in mid-March.

There is one vital ingredient to every snowshoeing trip. And that's snow. Pulling back the curtains of my hotel room window, I gazed out at the sheer slopes of Mount Etna. There wasn't a flake to be seen. Did Luca, my guide, have some bad news? "Don't worry," he said, while loading our snowshoes into the van.

British scientists have found scores of fossils the great evolutionary theorist Charles Darwin and his peers collected but that had been lost for more than 150 years.

A volcano on Alaska's Aleutian Islands sent up an ash cloud today which prompted scientists to increase the alert level for commercial air traffic.

A 6.7-magnitude earthquake struck Mexico's western Guerrero state today, shaking buildings and causing panic just over 100 miles away in the nation's capital.

Deforestation and extreme weather may later cause earthquakes, scientists believe.

Water, ash and rocks are flowing down the flanks of the Popocatepetl volcano southeast of Mexico City.