The formation is characterized by lagoonal facies with episodes of higher energy and rare bivalve patch reefs, such as
Chondrodonta and
Rudists, which are found throughout the entire unit. The lower section, referred to as the
"Zolla member" consists of bivalve-rich limestone, including rudists and
Chondrodonta, as well as foraminiferal limestone, often interbedded with dolomitized dark wackestones. In the upper part of this member, pelagic limestone with
Pythonella fossils is present. The main body of the
Aurisina Limestone is characterized by peritidal carbonates, with some dark laminated facies, dominated by rudists, benthic foraminifera, cyanobacteria (
Decastronema), and algae (
Thaumatoporella). The Paleoenvironment of this unit is accepted to be a succession of emerged and shallow marine carbonate platform settings, including inner lagoons, high-energy shoals, tidal channels, and rudist accumulations The complex dolomitization and silicification in the region may be linked to a
Monsoon climate with alternating wet and dry periods. Comparable dolomitization occurs across the
Adriatic Platform, particularly in the Middle-Lower Cenomanian. The Villaggio del Pescatore fossil site records a progressive environmental shift from a stable shallow-marine carbonate platform to a restricted, tectonically controlled basin.
Rudist-bearing facies developed during this stage, though their small size suggests ecologically stressed conditions. Later, higher-energy shallow-marine settings produced bioclastic sands and rudstones under well-oxygenated conditions. During the Lower
Senonian, synsedimentary tectonic activity disrupted the platform, creating a small fault-bounded depression. Differential block movements led to erosion of emergent areas and collapse of basin margins, generating polygenic breccias composed of reworked platform material, including clasts showing oxidation, pedogenic alteration, and evidence of subaerial exposure. As tectonic activity decreased or relative sea level rose, clastic input diminished and the basin evolved into a quiet, restricted water body. The depression was progressively filled by finely laminated limestones deposited under low-energy conditions with limited circulation and oxygen-poor bottom waters. Seasonal lamination indicates cyclic sedimentation, consistent with fluctuating freshwater input and variable salinity in a brackish
lagoon or shallow coastal lake. Microfossils, freshwater algae, plant traces, and slump structures reflect continental influence and ongoing instability along the basin margins. These anoxic conditions enabled exceptional preservation of vertebrate remains, including hadrosaurs, crocodyliforms, fish, and crustaceans. The surrounding bauxite and coal deposits indicate a humid climate and a karst landscape where surface water was scarce, making the basin a persistent water source. The depression likely functioned as a
cenote-like feature that attracted animals, some of which drowned and were preserved at its stagnant base. A subsequent Upper Santonian transgression restored open-marine carbonate platform conditions, sealing the restricted basin deposits and preserving the unique fossil record. == Biota ==