Question

An aqueous polyphase (L + V + solid) inclusion contains a halite daughter crystal at room temperature and pressure. Which of the given statements is CORRECT in relation to this inclusion?

• A. The salinity of the bulk aqueous fluid can be determined from the temperature of melting of ice.
• B. The salinity of the bulk aqueous fluid can be determined from the temperature of dissolution of halite.
• C. The density in all cases can be determined from the temperature of liquid-vapor homogenization.
• D. The density in all cases can be determined from the temperature of dissolution of the halite daughter crystal.

Hint:

In fluid inclusions, the dissolution temperature of salts like halite is a reliable method to estimate the salinity of the fluid.

Answer 1

The Correct Option is B

In an aqueous polyphase inclusion with a halite daughter crystal, the salinity of the bulk aqueous fluid is primarily determined by the temperature at which the halite crystal dissolves. This is because halite (NaCl) is highly soluble in water, and the dissolution temperature of halite can be correlated with the salinity of the fluid.
[6pt] - (A) is incorrect because the temperature of ice melting only indicates the freezing point of the fluid, not its salinity.
- (C) is not relevant in this case as the density is typically related to the phase transitions of the fluid, not to liquid-vapor homogenization.
- (D) is also incorrect because the temperature of dissolution of the halite daughter crystal specifically helps determine salinity, not density.
Therefore, the correct statement is (B): The salinity of the bulk aqueous fluid can be determined from the temperature of dissolution of halite.