In the area of Lambou Myloi, the impressive thrust of the tectonic cover of the ophiolitic rocks, about 150 million years old, appears, on top of the metamorphic rocks of the background of Lesvos.
Ophiolites are a group of igneous rocks created by the eruption of magmatic material originating from the earth’s mantle, during the process of removing the continents and creating the ocean floor. The ophiolitic rocks of Lesvos come from the oceanic space of the Tethys ocean, which extended south of Eurasia. 150 million years ago the ocean was constantly expanding and new ophiolitic rocks were created by magma seeping in between the two great continents of Laurasia in the north and Gondwana in the south. The rocks that compose this group consist of peridotites, dunites, gabbros, basaltic lavas, pillow lavas, etc.
150 million years ago the two mega-continents begin to converge resulting in the compression and destruction of the Tethys Ocean. The rocks that formed its ocean floor were compressed, emerged and placed on the margin of the Eurasian lithospheric plate, hundreds of kilometers away from their point of creation.
Today, in the area of Lambos Myloi, the ophiolites are placed over slates and marbles that are 250-300 million years old. The pine forest of central Lesvos grows on the ophiolitic rocks, while the olive groves of the region grow on the metamorphosed rocks.
The impressive change of vegetation from the olive groves to the pine forest can be seen on the road axis Mytilini – Kalloni, in the area of Lambou Myloi.