Ectasian

The Ectasian Period is a special time in Earth's history. It was the second geologic period in the Mesoproterozoic Era. It lasted from 1400 million years ago to 1200 million years ago.

The name "Ectasian" comes from a Greek word meaning "extension." During this time, the layers covering Earth's platforms grew thicker.

Scientists use special tools to find the exact dates for this period. They do not just look at rocks and layers.

In the early part of the Ectasian Period, a day on Earth was 17 hours and 32 minutes long. By the end of this period, a day had become a little longer, to 18 hours and 28 minutes. This slow change helps us learn how our planet has been changing over very long times.

Geology

During the early Ectasian time, a huge landmass called Columbia was still together until about 1.35 billion years ago. Near a place called Laurentia, the land began to pull apart. Columbia became unstable and finally split apart between 1.3 and 1.2 billion years ago. During this time, large groups of volcanic rocks formed, like the Mackenzie dike swarm in Canada and the Galiwinku dyke swarm in Australia. Scientists think that a huge flow of heat from deep inside the Earth, called a superplume, formed around this time and helped change the land and cause Columbia to break apart. This superplume affected three areas and helped the land spread out.

Biology

The Dismal Lakes group, which existed from 1590 to 1270 million years ago, has tiny fossils. Scientists think these fossils are eukaryotes, a simple kind of living thing. Many different kinds of these tiny plants appeared in this group.

During the Ectasian period, we also see more acritarchs. Acritarchs are very small, simple plants, along with many eukaryotes.

Climate

The Ectasian Period began with the end of an event that raised oxygen levels in the air. During this time, oxygen levels stayed low, similar to the "Boring Billion" years.

The ocean had less oxygen, especially in deeper areas. Shallow parts near the shore may have had small areas with more oxygen, helping some simple life survive. The water temperature was about 27 degrees Celsius, a little warmer than today’s oceans.