This paper describes a four-day excursion to Lavrion peninsula (SE Attica Greece), located at the northwestern area of the Attic-Cycladic complex. Numerous metamorphic core complexes are identified within the Attic Cycladic complex. They were formed when Oligo-Miocene extension destroyed the nappe pile created due to Eurasia-Gondwana convergence. One of these metamorphic core complexes is located in SE Attica.

The geological structure of SE Attica is largely controlled by the existence of a major crustal scale brittle-ductile shear zone with a top to SW sense of shear. This shear zone corresponds to the continuation of the West Cycladic Detachment System (WCDS) in Attica. The footwall of the detachment comprises the lower part of Kamariza Unit, which is only exposed at the eastern part of Lavrion peninsula. The LANF zone mainly consists of the ultramylonitic Upper Kamariza Marble as well as some lithologies from the overlying metamorphosed Lavrion Unit that are only affected by the brittle deformation related to the WCDS. The hanging wall includes the metamorphosed Lavrion Unit, the non-metamorphosed Berzekos Unit and sparse Neogene sediments. The footwall is intruded by numerous late Miocene granitic intrusives whereas only a few dikes pierce through the detachment. Massive fluid infiltration mainly along the LANF zone and low-angle brittle faults in the hanging wall is responsible for the famous Lavrion silver ore deposits that were exploited during the Golden Age of Athens.

The main structures and features of SE Attica geology can be explored in a five-day field excursion which includes some related archaeological aspects.