Karstification without carbonic acid; bedrock dissolution by gypsum-driven dedolomitization, 1994, Bischoff Jl, Julia R, Shanks Wc, Rosenbauer Rj,

Aggressive karstification can take place where dolomite and gypsum are in contact with the same aquifer. Gypsum dissolution drives the precipitation of calcite, thus consuming carbonate ions released by dolomite. Lake Banyoles, in northeastern Spain, is a karst lake supplied by sublacustrine springs, and karstic collapse is occurring in the immediate vicinity of the lake. Lake water is dominated by Mg-Ca and SO 4 -HCO 3 , and is supersaturated with calcite that is actively accumulating in lake sediments. Water chemistry, sulfur isotope composition, local stratigraphy, and mass-balance modeling suggest that the primary karst-forming process at Lake Banyoles is dedolomitization of basement rocks driven by gypsum dissolution. Karstification takes place along the subsurface contact between the gypsiferous Beuda Formation and the dolomitic Perafita Formation. This process is here recognized for the first time to cause karstification on a large scale; this is significant because it proceeds without the addition of soil-generated carbonic acid. Gypsum-driven dedolomitization may be responsible for other karstic systems heretofore attributed to soil-generated carbonic acid

KARSTIFICATION WITHOUT CARBONIC-ACID - BEDROCK DISSOLUTION BY GYPSUM-DRIVEN DEDOLOMITIZATION, 1994, Bischoff Jl, Julia R, Shanks Wc, Rosenbauer Rj,

Aggressive karstification can take place where dolomite and gypsum are in contact with the same aquifer. Gypsum dissolution drives the precipitation of calcite, thus consuming carbonate ions released by dolomite. Lake Banyoles, in northeastern Spain, is a karst lake supplied by sublacustrine springs, and karstic collapse is occurring in the immediate vicinity of the lake. Lake water is dominated by Mg-Ca and SO4-HCO3, and is supersaturated with calcite that is actively accumulating in lake sediments. Water chemistry, sulfur isotope composition, local stratigrapy, and mass-balance modeling suggest that the primary karst-forming process at Lake Banyoles is dedolomitization of basement rocks driven by gypsum dissolution. Karstification takes place along the subsurface contact between the gypsiferous Beuda Formation and the dolomitic Perafita Formation. This process is here recognized for the first time to cause karstification on a large scale; this is significant because it proceeds without the addition of soil-generated carbonic acid. Gypsum-driven dedolomitization may be responsible for other karstic systems heretofore attributed to soil-generated carbonic acid

Dynamics of hydrothermal plumes in Lake Banyoles, 2008, Soler I Ortega, Marianna

The aim of this thesis is to acquire a better understanding of the dynamics of the hydrothermal plumes in the lake and to gain more insight into the interrelationship between meteorology and fluidization. They have been found the atmospheric patterns that generate the fluidization events, as well as their frequency. This is crucial to determining the water quality of Lake Banyoles. They have been found spatial inhomogeneities of the chronic thermal plume found in B1 and of the episodic thermal plume in B2. The structure of thermal plume in B2 has been characterized and compared to the plume developed in B1. Finally, it has been used a numerical model: MIT General Circulation Model. It has been necessary to modify the boundary conditions moving the buoyancy source from the top of the water surface to the bottom. Results have been compared to experimental data undertaken from the field campaigns.