Abstract
Glauconite is commonly found in the Lower Senonian of the Gulf of Suez (Nezzazat Group Matulla Forma- tion) and the Egyptian Western Desert (Upper Bahariya Formation) in sufficient quantities to have an impact on density, neutron, Pe, and resistivity log response. Glauc- onite is a complex mineral composed mainly of iron, potassium, and magnesium hydrated aluminum sili- cates. Due to its complex mineralogy in particular varia- tions in iron content, it has a wide range of grain densi- ties. Modeling the effects of glauconite on the responses of density, Pe and neutron porosity logs has been used to improve the determination of porosity and lithology from well log data.