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Minerals and speleothems of the József-hegy Cave (Budapest, Hungary).Keywords: thermal karst cave , cave minerals , U/Th age , Budapest , József-hegy Cave Abstract: With the discovery of the József-hegy Cave, a cave of hydrothermal origin with an abundance of minerals unknown so far in Hungarycame to light. Diversity and the frequency of the occurrence of crystals make this cave similar to the Lechuguilla Cave, even ifthe dimensions of the mineral precipitations and the passages do not compare in scale. The variety and mass of carbonates andsulphates are surprising. This paper describes the minerals and speleothems of the József-hegy Cave, their occurrence and genesis,including determined ages. The 41 U/Th measurements suggest that speleothems begun to develop in the upper level of the cavemore than 350 ka ago. Some of these dated old speleothems were developing in dry passages, thus the uppermost passages of theJózsef-hegy Cave have been dry at least for 350 ka. The karst water level was still at the main passage 200 ka ago and dropped to120 m asl by the time of ~100 ka before present.
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