A system and method for extracting and testing cave secondary carbonate fluid inclusion water

Abstract

The invention discloses a system and method for extracting and testing secondary carbonate fluid inclusion water in caves. The secondary carbonate fluid inclusion water in caves is extracted by crushing and grinding in a high-temperature vacuum environment, transported by carrier gas and Thoroughly mix, and use wavelength-scanning optical cavity ring-down spectroscopy to test and analyze cave secondary carbonate inclusion water, including carrier gas storage device, pressure gauge, injection port, crushing grinder, filter, buffer bottle , a vacuum pump, a water isotope analyzer, and a pipeline connected by various valves. There is a heating device on the outside of the pipeline, and the crushing grinder includes a device composed of a driving device, a piston, a sample holding box and a heating device. The hydrogen and oxygen isotope values ​​of secondary carbonate fluid inclusion water in caves can be quickly obtained with high precision by using the device and method of the invention.

Description

technical field [0001] The invention relates to the field of geochemistry, in particular to a system and method for extracting and testing secondary carbonate fluid inclusion water in caves. Background technique [0002] Cave secondary carbonate fluid inclusions are formed during the growth of cave secondary carbonate due to defects in the calcium carbonate crystal structure, sealing gas and liquid in the lattice structure, and they preserve the deposits during the formation process. The original information at that time, and less affected by the external environment after the formation of inclusions. By measuring the hydrogen and oxygen isotopes (δ 18 O and δD) values ​​can be used to calculate the temperature of the cave when the inclusions were formed, and the average temperature outside the cave can be calculated, and then the temperature change history of the research area can be reconstructed. [0003] The existing methods for extracting water from secondary carbonat...

AI Technical Summary

Problems solved by technology

The direct extraction method requires making thin slices of secondary carbonates in caves, selecting suitable inclusions under a microscope and drilling with a micro-drill, and using a syringe to extract the water in the inclusions for testing. This method has stricter requirements on samples. , need to have larger inclusions to test, poor applicability

The vacuum mechanical crushing and grinding method is to crush the sample by manually rotating the piston to apply pressure under the vacuum condition of 120-150°C, but this crushing method often cannot completely crush the cave secondary carbonate sample due to insufficient pressure. , causing part of the inclusion water to be unable to be extracted

At the same time, this method cannot test large cave secondary carbonate samples, resulting in samples with low water content that cannot be tested and analyzed by increasing the amount of samples tested, making this method not universal

The broken sample powder also has the risk of entering the testing equipment, thus affecting the normal operation of the equipment

[0004] Cave Secondary Carbonate Fluid Inclusion Water δ 18 The test method of O and δD is mainly continuous flow isotope ratio mass spectrometry, which needs to convert water molecules into molecular species suitable for hydrogen and oxygen isotope analysis through a high-temperature elemental conversion analyzer. There are potential isotope fractionation and other problems during the conversion process. Affect test analysis results

Using this method, it is necessary to collect the inclusion water released by breaking at high temperature through a cold trap, followed by rapid heating. Frequent temperature changes may cause isotope fractionation and affect the test results.

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