Huntite deposits in the neogene lacustrine sediments of the Cameli basin, Denizli, SW Turkey

Abstract

Extremely white huntite having friable, earthy character occurs in the Cameli basin which was downthrown along reverse faults during neotectonic activity. The basement comprises dolomitic limestone and peridotite which were the main sources of Mg for huntite formation. These units are overlain unconformably by conglomerate, sandstone, and mudstone of a fan-delta environment and, locally, by swampy facies, and by dolomite-dolomitic marl-huntite and karstic limestone which represent mud-flat and open-lake sediments, respectively. The huntite occurs as 0.5-3-m-thick massive deposits as well as fillings of fenestral dissolution voids and as sheet cracks in dolomitic marl, dolomite and limestone which are evidence of arid to semi-arid climatic conditions. Massive huntite with dolomite and/or hydromagnesite/magnesite probably formed by diagenetic processes in light of the gradational contact of huntite with dolomite in the Sucati huntite deposit. While discoidal and fenestral huntite formed by direct precipitation of Mg-rich pore waters in shallow coastal sediments of a mud-flat environment, the huntite flocculated during the precipitation of karstic limestone, probably in a pluvial climatic regime.