STORY: This is the Brazilian island of Trindade.
Its geology has fascinated scientists for years.
But the latest discovery on this remote turtle refuge, has terrified them.
These rocks are made from plastic debris.
Melted plastic has become intertwined with rocks on the island - located more than 700 miles away from the mainland.
And scientists say it's proof of mankind's growing influence over earth's geological cycles.
Trindade Island is one of the world's most important conservation spots for green turtles - with thousands arriving each year to lay their eggs.
The island’s only human inhabitants are members of the Brazilian navy - which maintains a base on the island and protects the nesting turtles.
But its remoteness did not stop human activity from interfering.
Fernanda Avelar Santos, Geologist:
“The place where we found these samples (of plastic) is a permanently preserved area in Brazil, near the place green turtles lay their eggs. It has a unique biodiversity with endemic species of fish, coral reefs, marine birds and protected species of crab, for example."
Researchers at the Federal University of Parana couldn’t classify the rocks...
So they ran chemical tests, which found that the plastics in the rocks are called “plastiglomerates” – made from a mixture of sedimentary granules and other debris held together by plastic.
“We identified (the pollution) mainly comes from fishing nets, which is very common debris on Trinidade Island’s beaches. They (nets) are dragged by the marine currents and accumulate on the beach. When the temperature rises, this plastic melts and becomes embedded with the beach's natural material."
Santos says the discovery stirs questions about humans' legacy on earth.
“We ran a chemical analysis to know the kind of plastic, and we also addressed these samples as if they were natural rocks, using the same research methods. Then we observed them in a macro and a micro way and described the samples as rocks. This is also part of the discoveries of our work – marine pollution seen from the geology perspective. This is new and terrifying at the same time because pollution has reached geology, and plastic can be preserved in the geologic report of the Earth."