Abstract
The Northern Geological Mapping Division has completed the geological investigation and mapping at scale of 1:50 000 over the whole Hạ Lang Structural Zone of ~2400 km2. The carbonate rocks are widely distributed on ~1550 km2, in the Nà Quản (D1-D2c nq), Bản Cỏng (D2gv bcg), Nà Đắng (D2gv-D3fr nđ), Tốc Tát (D3-C1 tt), Bắc Sơn (C-P bs), Lũng Nậm (C1 ln) Formations. The results of 1:50 000 geological mapping and mineral investigation in the Cách Linh, Bản Nưa, Bản Thần, Thượng Thôn, Quang Long, Quảng Uyên, Nà Vường demonstrated that the carbonate rocks show good quality, large scale and can be used as industrial, construction materials and gemstone production. The carbonate rocks also produce other geological values such as karstic caves, water falls and natural landscape for tourism purposes.