TITLE:
Isotope Dating of the Potash and Rock Salt Deposit at Bamnet Narong, NE-Thailand
AUTHORS:
Bent T. Hansen, Klaus Wemmer, Monique Eckhardt, Prinya Putthapiban, San Assavapatchara
KEYWORDS:
Isotope Dating, Salt Deposits, Mid-Cretaceous, Asian Potash Mine, Thailand
JOURNAL NAME:
Open Journal of Geology,
Vol.6 No.8,
August
22,
2016
ABSTRACT: Bamnet Narong is located in northeastern Thailand (Chaiyaphum Province). It
is the largest salt mine in the country and has been mined for decades. The
landscape in this part of Thailand is characterised by a low plateau, which is
called the Khorat Plateau. The plateau is divided into two basins by the Phu
Phan Range, the Sakhon Nakhon Basin in the north and the Khorat Basin in the south. The analysed potashes and rock salts are
deposited in the Maha Sarakham Formation, which represents the
salt-bearing strata of the Khorat Basin. The stratigraphic age of this deposit
has been debated since the late 1960’s. The assigned ages range from
Mid-Cretaceous to Late Cretaceous and up to the Eocene. In this study different
isotopic dating systems (Rb-Sr, Sr-Sr, K-Ar and K-Ca) were applied. The
stratigraphic age for the time of deposition was confirmed to be Mid Cretaceous
(Cenomanian). Furthermore, the homogeneity of the carnallites was investigated
in order to trace a possible redistribution of rubidium.