Dynamic processes in the Venice region outlined by environmental isotopes

Area of Science:

• Hydrogeology
• Geochemistry
• Sedimentology

Background:

• Groundwater circulation in the Venice region is crucial for understanding its hydrogeology.
• Hydrodynamic processes are significantly influenced by a cemented sedimentary layer known as 'caranto'.
• The caranto layer, formed by subaerial cementation, acts as a regional aquitard.

Purpose of the Study:

• To investigate the hydrogeological significance of groundwater circulation in the Venice plain and lagoon.
• To understand the role of the 'caranto' layer in controlling hydrodynamic processes.
• To analyze the formation of carbonate rocks within sediments and their impact on isotopic reconstructions.

Main Methods:

• Analysis of groundwater circulation patterns.
• Isotopic analysis of deep aquifers and pore waters.
• Investigation of sedimentary layers and cementation processes.

Main Results:

• Groundwater circulation is heavily influenced by the 'caranto' aquitard.
• Anthropogenic activities perturb hydrodynamic conditions, complicating present recharge estimations.
• Carbonate rock formation is linked to seepage of gaseous carbon compounds, producing CO2 and causing cementation.

Conclusions:

• The 'caranto' layer is a key hydrogeological feature in the Venice region.
• Reconstructing past recharge regimes requires considering deep groundwater and pore water, especially due to anthropogenic impacts.
• The formation of carbonate rocks through CO2-induced cementation is a significant process affecting sediment properties and isotopic signals.