The reason for this is, that after the volcanism, the entire mountain range tilted southward due to the subsidence of the trench extending south of the Mátra and Bükk.

The southern, more gentle part was buried by young sediments, while on the northern side steep slopes were formed by landslides during the Pleistocene.

Excluding these, the oldest formations are located along the fault system called the Darnó line, which runs northeast-southwest through the Eastern Mátra.

The driving force of the volcanic activity was the juxtaposition of the two rock plates that make up the Carpathian Basin region, the Alcapa and the Tisza-Dacia.

The Mátra formed 13-18 million years ago as part of a series of events that are also significant in the geological history of our European continent.

Its local variant was called Tar dacitetuff due to its relatively lower silicon content, the exact age of which is unknown; its formation time may be between 15-18 million years.

The andesite lava blanket, which also determines the present-day landforms of the Mátra, was formed at about the same time as the formation of the Tar dacitetuff or 1-2 million years later, during the Miocene intermediate volcanism.

Andesitic lava – compared to rhyolite-dacite – is less violent, and instead of explosive, it comes to light during effusive eruptions, which do not involve caldera formation.

With the end of andesite volcanism, diatomaceous earth (diatomite) and then limestone were deposited in the basin between Gyöngyöspata and Szurdokpüspöki, and at the end of the Miocene volcanism, some smaller rhyolite volcanoes were still active on the southern edge of the mountain range (one of the remains is the swelling cone of Kis-hegy at Gyöngyössolymos).

[1] The Mátra is part of the North Hungarian Mountains and belongs by origin to the largest young volcanic zone of Europe.