Abstract
Preliminary hydrogeological and geochemical observation were conducted in the Phong Nha—Ke Bang National Park and Tu Lan Karst Area, Quang Binh Province, Vietnam to evaluate and document the hydrogeologic conditions, karst surface features, water geochemistry and limestone composition. The study area provides an excellent benchmark for karst hydrogeological investigations in central Vietnam. The data generated from this project will guide future research and conservation efforts of this unique karst landscape. Five rock samples and 20 water samples were collected in 2016. Four of the five rock samples are pure limestones, easy to dissolve which combine with a well-developed secondary porosity, and large amount of rain, forms a good environment for karst landscape and cave formation. There is a significant variation between 20 study sites in water chemistry baseline, specific conductance and temperature. The water samples had slightly acidic-to-neutral pH values (6.15–7.91), moderate specific conductance (SC) and total dissolved solids (TDS) values 65–418 μS/cm and 32–209 milligrams per liter (mg/L), respectively. Temperatures varied from 17.9 to 22.8 oC. ORP ranged from 68 to 194 at Phong Nha Cave outlet. Total alkalinity as CaCO3 fluctuates between 38 mg/L and 166 mg/L and total hardness ranged between 28 mg/L and 248 mg/L CaCO3. All samples exhibit slightly elevated chlorite, nitrate, and sulphate levels.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
