Methane Bubbling Through Seafloor Creates Undersea Hills

According to a recent paper published by MBARI geologists and their colleagues, methane gas bubbling through seafloor sediments has created hundreds of low hills on the floor of the Arctic Ocean. These enigmatic features, which can grow up to 40 meters (130 feet) tall and several hundred meters across, have puzzled scientists ever since they were first discovered in the 1940s. Writing in the January issue of Geophysical Research Letters, MBARI geologists Charlie Paull and William Ussler and their coauthors described the results of fieldwork they conducted on the Beaufort Sea Shelf, offshore of the north coast of Canada. In this area of year-round sea ice and permafrost, the team spent over a month mapping the seafloor and collecting sediment cores and gas samples from these underwater hills, which they call "pingo-like features."...