Valanginian

The Valanginian is an important time in Earth's history. It is part of the Early or Lower Cretaceous. This helps scientists figure out how old things are. The Valanginian lasted from about 137 million years ago to around 133 million years ago.

This time comes after the Berriasian Stage and before the Hauterivian Stage. By looking at rocks and fossils from the Valanginian, scientists learn about plants, animals, and the environment from long ago. It helps us understand how life on Earth has changed over millions of years.

Stratigraphic definitions

The Valanginian was first described and named by Édouard Desor in 1853. It is named after Valangin, a small town north of Neuchâtel in the Jura Mountains of Switzerland.

The Valanginian is often split into Lower and Upper parts. In the Tethys domain, this stage has five areas. These areas are defined by different types of ammonite fossils.

Climate

During the Valanginian period, Earth went through big environmental changes. These changes might have been caused by volcanic activity from large areas of lava flow, called large igneous provinces, in places that are now South America and Africa. This volcanic activity put substances into the atmosphere, changing the planet's climate.

These events affected life in different ways. Marine organisms had a hard time, while land ecosystems may have actually benefited. The warm, wet conditions helped plants grow widely, supporting the development of new types of plants, including the first flowering plants.