Name: Monte Bolca Location: Northern Italy Age: Eocene

Geological setting and age

• Monte Bolca was uplifted during the Alpine Orogeny (specifically the mid-Alps), the date of which is poorly constrained but which occurred in two stages, one between 50-30 million years ago and one c.24 million years ago.
  
• The Pesciara locality consists of about 19 metres (in section) of limestones that dip steeply to the south-west.

The Pesciara locality consists of about 19 metres (in section) of limestones that dip steeply to the south-west. The shaded areas on this stratigraphic section represent laminated carbonate mudstones, these are the Lagerstatten layers. Fossils are found in other horizons but do not have the same exceptional preservation as those from these laminated horizons. (Modified from Tang, 2002)

• The sediments were deposited at the margin of the Mediterranean Sea on a large costal platform, intersected by vegitated barrier islands and coral reefs.
  
• The age of the Monte Bolca site has been placed at around 49 million years ago, correlated by the presence of a distinctive coccolith, Discoaster sublodensis, which is know to have been extant during the lower Mid. Eocene.

Paleoenvironment

• Pelagic marine, sea grass beds, coral reef, brackish lagoons and terrestrial habitats are all represented faunally in the Monte Bolca Lagerstatte.
  
• Bolca fishes, the dominant fauna, have been interpreted as "a costal tropical fish fauna containing both benthic and open-water forms" (Bellwood, 1998).
  
• It has been suggested that the Bolca fishes are the first known reef fish assemblage but evidence of interaction with the reef is lacking. The facies have been displaced (the only direct evidence of a reef assemblage being transported coral clasts).