This paper deals with Sedimentological Petrology of Nagdong Group (Upper Jurassic(?) to Lower Cretaceous) at Goreong area in Gyeongsang Province, Korea.
The Nagdong Group has four Chronological subdivisions, that is Yeonhwadong, Hasandong, Dongmyeong...
This paper deals with Sedimentological Petrology of Nagdong Group (Upper Jurassic(?) to Lower Cretaceous) at Goreong area in Gyeongsang Province, Korea.
The Nagdong Group has four Chronological subdivisions, that is Yeonhwadong, Hasandong, Dongmyeong, and Chilgog formations. Such subdivisions are based on mainly rock color and lithological features.
78 sandstone samples were taken and studied upper ordinary polarizing microscope with great emphasis of mineral constituents and grain size parameter.
The obtained results may be summerized as the following.
The type of sandstone is arkose, subarkose, and great amount of graywacke (according to Dapples sandstone classification, 1953).
The sandstone are also moderately well sorted to moderately sorted (according to Folk and Ward, 1957) and near symmetrical to fine skewed (according to Folk and Ward, 1957). Kurtosis of the sandstone belongs to meso kurtic to lepto kurtic (according to Folk and Ward, 1957).
Grain size parameter analysis shows that the sandstones are deposited sediments under fluviatile environment.
Mineral constituents identified also shows that the provenance of the Nagdong Group in the thesis area is polygenetic terrain of Metamorphic rocks with little amouts of granitic and Sedimentary rocks.