GSA Annual Meeting in Phoenix, Arizona, USA - 2019

Paper No. 26-6
Presentation Time: 9:00 AM-5:30 PM


SELBY, Mildred M., NASA MUREP Aerospace Academy, York College-CUNY, 94-20 Guy R. Brewer Blvd, AC-2F09, Jamaica, NY 11451, KHANDAKER, Nazrul I., Earth and Physical Sciences Department - Geology Discipline, York College-CUNY, 94-20 Guy R. Brewer Blvd, AC-2F09, Jamaica, NY 11451, SELBY, Elton, SUNY Buffalo State College, 1300 Elmwood Avenue, Buffalo, NY 14222, ANDERSON, Hetty, Takoradi Polytechnic Institute, Takoradi, 00233, Ghana and KWOFIE, Ebenezer Kobena, University of Cape Coast, Cape Coast, 23321, Ghana

Representative beach sands, mostly of recent origin, were collected from the Sekondi-Takoradi Area, Western Ghana to conduct both detrital mineralogy (light and heavy minerals), bulk oxide, and trace element investigation to infer provenance and depositional environment. Samples were collected along the shoreline from just below the surface to a depth of 2 feet below the surface. Wet sand samples were thoroughly washed, dried, and sieved using US Standard mesh (25 through 230). Overall sand samples are medium to fine grained sand size, (0.50 mm to 0.10 mm) and are moderately to well-sorted. Heavy minerals (density greater than 2.65 g/cc) were separated using an eco-friendly chemical solution, sodium poly-tungstate. Aside from rounded to well-rounded quartz, mica, and occasional feldspar grains, rutile, zircon, and amphibole were noted among the heavy minerals. To determine provenance, representative sand samples were analyzed for bulk oxide, trace elements including LREEs (Light Rare Earth Elements), and HREEs (Heavy Rare Earth Elements), since geochemical studies are not readily available on identification of rare earth elements and establishing a geochemical fingerprint for the coastal sands of Ghana. Total silica content (SiO2) predominated in all the samples followed by Al2O3, FeO, Na2O, MgO, and CaO. Rare earth elements were found in beach sands at both regions (Sekondi-Takoradi Area). Heavy REEs were reported by previous researchers and found in relatively higher concentrations in the beach sands of the Western region. The sum of light LREEs, HREEs and ratio of light to heavy rare earth (LREE/HREE) distribution in the Western beach sands were determined, and an overall enrichment of LREEs over HREEs in various sand sizes (medium to fine-grained) noted. The minerals found are known to concentrate REEs and are indicative of shore-derived materials.