GSA Annual Meeting in Phoenix, Arizona, USA - 2019

Paper No. 30-2
Presentation Time: 9:00 AM-5:30 PM


FREGOSO-SANCHEZ, Diana Carolina1, COMPTON, Kalyn2, GERMAINE CORINE, Ngameni Youaleu3, CHARLES, Njilah4, RAMATLAPENG, Goabaone5, ELLA, Kahnyuy6, BIKUU, Victorine A.7, COUNTS, Nicholas T.8, NJILAH, Isaac Knofor3, ATEKWANA, Eliot9 and ALI, Hendratta10, (1)Department of Civil and Environmental Engineering, California State University, Fullerton, 800 N. State College Blvd, Fullerton, CA 92831, (2)Fort Hays University, Hays, KS 67601; Fort Hays University, Hays, KS 67601, (3)Department of Earth Science, University of Yaounde I, Yaounde, Cameroon, (4)University of Yaounde I, Yaounde, Cameroon, (5)Department of Geological Sciences, University of Delaware, 210 South College Ave. Newark, DE, 312 Delaware circle, Newark, DE 19716, (6)Department of Microbiology, University of Buea, Buea, Cameroon, Buea, Cameroon; Department of Geosciences, University of Douala, Douala, Cameroon, (7)University of Buea, Buea, Cameroon, (8)Department of Geological Sciences, Fort Hays State University, 600 Park Street, Hays, Kansas, Hays, KS 67601, (9)Department of Geological Sciences, University of Delaware, Newark, DE 19717, (10)Department of Geosciences, Fort Hays State University, Hays, KS 67601

This study aims to investigate the relationship between surface and groundwater in the Youpwe neighborhood in the Wouri estuary. The objectives are to (1) determine tidal variations at select locations and to (2) compare and describe the physico-chemical characteristics of the surface and groundwater. We deployed data loggers at three locations: a mangrove, open water and a groundwater well. The three locations are within a radius of approximately 300 meters. Data were logged every minute for forty-eight hours. Temperature, pH, DO, ORP, TDS and salinity were recorded using a multi-parameter probe. Alkalinity was analyzed using a digital titrator in the field. Water samples were collected at each location for chemical analysis (cation and anion). Nitrate and iron concentrations were determined in field using a spectrometer. Temperature remained nearly constant at all sample locations. Water level and conductivity at all locations showed cyclical trends with lag variations of about two hours between them. The trend in the cycle in the mangrove and open water are in phase and both are out of phase with the groundwater. The highest change in water level of about 2 meters occurs at the mangrove. Conductivity values varied between 1976–4075 µS/cm at the mangrove, 275–3357 µS/cm in open water and 756–1038 µS/cm in the groundwater. Salinity varied between 0.94–1.98 psu at the mangrove, 0.83–1.70 psu in open water, and 1.07–1.46 psu in the groundwater. Alkalinity as CaCO3 was 33 mg/L at the mangrove, 275 mg/L in groundwater and 60 mg/L in open water. Total dissolved solids (TDS) varied between 2137–9632 ppm at the mangrove, 830-1635 ppm in open water and 1080–1421 ppm in the groundwater. The trends suggest that while the surface water parameters are mostly influenced by tidal variations, the groundwater is influenced by both tidal variations and factors such as subsurface geology and human activities.