Characterization of Neogene marls from the Kert Basin (northeast Morocco); suitability for the ceramics industry

• Published in: Clay minerals Vol. 54; no. 4; pp. 379 - 392
• Main Authors: Nasri, Hicham, Azdimousa, Ali, El Hammouti, Kamal, El Haddar, Abdelilah, El Ouahabi, Meriam
• Format: Journal Article
• Language: English
• Published: Middlesex Mineralogical Society 01.12.2019; Cambridge University Press
• Subjects: Africa; Age; Atterberg limits; Basins; Calcite; Cenozoic; ceramic materials; Ceramics; Ceramics industry; chemical properties; Chlorite; clastic rocks; Clay; clay mineralogy; Clay minerals; Construction materials; Cristobalite; Dolomite; Dolostone; Economic geology; Extrusion; Feldspars; Fluorescence; geochemistry; Geology; Grain size; Illite; Illites; Kaolinite; Kert Basin; Lithology; marl; Masonry; Messinian; Mineralogy; mixed-layer minerals; Morocco; Neogene; nonmetals; North Africa; northeastern Morocco; Oxidation; Particle size; Quartz; River banks; Rivers; Roofing; Sandstone; Sedimentary facies; Sedimentary rocks; Sedimentation; Sedimentation & deposition; sheet silicates; Siderite; silicates; Size distribution; Tertiary; Vermiculite; Vermiculites; Volcanic ash; X rays; X-ray diffraction; X-ray fluorescence; Morocco; Ceuta & Melilla Spain; Spain
• ISSN: 0009-8558; 1471-8030
• DOI: 10.1180/clm.2019.50

The Neogene marls from the lower Kert area (northeast Morocco) were characterized to evaluate their suitability for the ceramics industry. Two cross-sections involving all of the Neogene facies were studied on both banks of the Kert River. Grey and green marls occurring between sandstone and tuffs were characterized by mineralogical (X-ray diffraction) and physicochemical (grain size, Atterberg limits, X-ray fluorescence and specific surface area) analyses. The Neogene clays studied are mainly calcareous silty marls containing 13-20 wt.% calcite. They consist of quartz, calcite, feldspars, dolomite, illite, kaolinite, chlorite and 10-14 Å illite-vermiculite mixed layers. Cristobalite was detected only in the uppermost level of the green marls, and it originates from a volcanic ash of Messinian age. Trace amounts of siderite and rhodochrosite indicate reducing or locally oxidizing conditions during sedimentation or shortly thereafter. The marls have medium to high plasticity, making them optimal for extrusion. Raw Neogene marls are suitable for manufacturing structural clay products. More specific uses, such as hollow products, roofing tiles and masonry bricks, were supported by the geochemical results and grain-size distribution.