Ectasian

The Ectasian Period is a special time in Earth's history. It was the second geologic period in the Mesoproterozoic Era and lasted from 1400 million years ago to 1200 million years ago. The name "Ectasian" comes from a Greek word meaning "extension" because during this time, the layers covering Earth's platforms continued to grow thicker.

Scientists use special tools to decide the exact dates for this period instead of looking at rocks and layers. During 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 gotten a little longer, to 18 hours and 28 minutes. This slow change helps us understand 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. Around the western side of a place called Laurentia, the land started to pull apart. Slowly, 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 led to the land spreading out more.

Biology

The Dismal Lakes group, which existed from 1590 to 1270 million years ago, contains tiny fossils that scientists think are eukaryotes, a type of very simple living thing. Many different kinds of these tiny plants showed up in this group.

During the Ectasian period, we also see more acritarchs, which are very small, simple plants, along with a fair number of eukaryotes.

Climate

The start of the Ectasian Period saw the end of an important event that increased oxygen levels in the air. During most of this time, oxygen levels stayed low, similar to what we call the "Boring Billion" years.

The ocean during this period had less oxygen, especially in deeper parts. Shallow areas near the shore might have had small spots with more oxygen, helping some simple life forms survive. The temperature of the water was about 27 degrees Celsius, a bit warmer than today’s oceans.