By Sergio Queiroz
TRINDAD ISLAND, Brazil (Reuters) – The geology of Brazil’s volcanic Trinidad Island has fascinated scientists for years, but the discovery of rocks made of plastic debris in this remote turtle sanctuary is causing concern.
Melted plastic has become entangled with rocks on the island, located 1,140 kilometers (708 miles) from the southeastern state of Espiritu Santo, which researchers say is evidence of humans’ increasing influence on Earth’s geological cycles.
“This is new and terrifying at the same time, because pollution has reached the geology,” said Fernanda Avelar Santos, a geologist at the Federal University of Paraná.
Santos and her team conducted chemical tests to see what kind of plastic the rocks contain. They are called “plastiglomerates” because they are made of a mixture of sedimentary grains and other debris held together by plastic.
“We identified (pollution) coming mainly from fishing nets, which is a very common debris on Trinidad island beaches,” Santos said. “They (nets) are dragged by ocean currents and accumulate on the beach. When the temperature rises, this plastic melts and becomes part of the beach’s natural material.”
The island of Trinidad is one of the world’s most important conservation sites for green turtles, or Chelonia midas, where thousands arrive each year to lay their eggs. The only human inhabitants of Trinidad are members of the Brazilian Navy, which maintains a base on the island and protects the nesting turtles.
“The place where we found these (plastic) samples is a permanently preserved area in Brazil, near where green turtles lay their eggs,” Santos said.
Santos says that this discovery raises questions about the heritage of humans on Earth.
“We talk a lot about the Anthropocene, and this is it,” Santos said, referring to a proposed geological epoch defined by the impact of humans on the planet’s geology and ecosystems.
“Pollution and trash in the sea and plastic improperly dumped in the oceans have become geological materials…preserved in Earth’s geological records.”
(Reporting by Sergio Queiroz for Reuters TV; Writing by Stephen Grattan; Editing by Sonali Paul)
