Sentences with phrase «ancient lake sediments»

Although scientists can learn about past climate by examining ancient lake sediments, in the Sahara the lakes dried up long ago and their sediments have blown away.

Ancient lake sediments in China record epic temperature swings, biotic turnover before the mass extinction.

The elevated silica in halos was found over approximately 20 to 30 meters in elevation near a rock - layer of ancient lake sediments that had a high silica content.

Not exact matches

The sediments, which contain evidence of Inca farming including the remains of seeds and mites that feed on llama dung, come from Marcacocha, a small lake near Cuzco, Peru, at the heart of the ancient empire.

Walter mapped likely methane deposits across the region; quantified how much methane, formed when permafrost melts, is bubbling out of current lakes; and compared that with the amount emitted from methane - laden sediments taken from ancient frozen lakes.

In central China's Jishi Gorge, gray sediment layers — now well above the Yellow River — indicate an ancient lake created in a landslide and then released by a devastating earthquake.

Lake sediments have long been a rich trove of clues to ancient human history — but often only indirectly so.

Using ancient DNA, along with the remains of pollen, plants, and animals collected from lake sediments, a new study has an answer: about 12,600 years ago.

An ancient record Assessing lake sediment cores from the region reaching 15,000 years into the past, a Montana State University team found whitebark pines more abundant despite higher summer temperatures and fire frequency than today.

To arrive at those conclusions, the researchers used sediment cores from Lake Towuti, an ancient lake on the island of Sulawesi in central IndoneLake Towuti, an ancient lake on the island of Sulawesi in central Indonelake on the island of Sulawesi in central Indonesia.

Sediment core samples drawn from Lake Titicaca, South America's largest freshwater lake, have revealed a 25,000 - year precipitation record that may rewrite the books on ancient climLake Titicaca, South America's largest freshwater lake, have revealed a 25,000 - year precipitation record that may rewrite the books on ancient climlake, have revealed a 25,000 - year precipitation record that may rewrite the books on ancient climate.

Since desiccation mudcracks form only where wet sediment is exposed to air, their position closer to the center of the ancient lake bed rather than the edge also suggests that lake levels rose and fell dramatically over time.

By measuring the bonds of prehistoric alkenones preserved in ancient layers of lake sediment, the team opened a window on Arctic temperature change since the end of the last Ice Age.

Ancient sediments that once resided on a lake bed and the ocean floor show sulfur isotope ratios unlike those found in other samples from the same time, calling into question accepted ideas about when the Earth's atmosphere began to contain oxygen, according to researchers from the U.S., Canada and Japan.

Lake sediment cores have been used to look at ancient biodiversity levels from 6 — 12.6 thousand years before present.

Robert Smithson is interested in modern types of industry, quarries and salt lakes, prehistoric layers of sediment and puzzling ruins of ancient and modern civilisation.

From the University of California — Berkeley Deep sediments are unparalleled record of biotic changes over past 200,000 + years University of California, Berkeley, scientists are drilling into ancient sediments at the bottom of Northern California's Clear Lake for clues that could help them better predict how today's plants and animals will adapt to climate change...

A recent study of ancient lake - bottom sediments found layers of charcoal next to layers of shrub pollen, suggesting a close link between shrubs and wildfire.

This is a survey of the ancient levels of lakes, rivers and the sea, as well as changes in the compositions of stalagmites and sediments.