Micro- and Nanotexture and Genesis of Ball Clays in the Lower Cretaceous (SE Iberian Range, NE Spain)

Bauluz, Blanca (Universidad de Zaragoza) ; Mayayo, María José (Universidad de Zaragoza) ; Laita, Elisa (Universidad de Zaragoza) ; Yuste, Alfonso (Universidad de Zaragoza)

Resumen: Ball clay deposits in the SE of the Iberian Range (NE Iberian Peninsula) consist of Albian clays and siltstones with greyish and blackish colors, interbedded with subbituminous coals. The ball clays are nowadays mined for the manufacture of white color ceramics. The mineralogy of these deposits consists mainly of kaolinite, illitic phases, and quartz. The euhedral to sub-euhedral morphology of the kaolinites suggests their in-situ origin. The anhedral morphology of the illites and the presence of frayed illites suggest a detrital origin. At the micro-scale, authigenic kaolinite booklets are observed filling pores and forming micakaolinite intergrowths, in which the kaolinite grows between the cleavage sheets of pre-existing detrital mica. At nanometer scale, illitesmectite (IS) phases are detected forming interlayers with mica and kaolinite, and evidence of the replacement of mica by kaolinite is observed. The matrix consists of defective illite and kaolinite, and random mixed layers of kaolinite-IS (Kln-IS), illite-IS (Ilt-IS), and IS-smectite (IS-S). The textures of illite and the presence of different types of mixed layers suggest that the expandable phases and kaolinite are products of mica alteration. The effectivity of the alteration was probably a consequence of the low pH that occurred in the environment due to the presence of abundant organic- and acidic- rich fluids.

Idioma: Inglés

DOI: 10.3390/min11121339

Año: 2021

Publicado en: Minerals 11, 12 (2021), 1339 [15 pp.]
ISSN: 2075-163X

Factor impacto JCR: 2.818 (2021)

Categ. JCR: GEOCHEMISTRY & GEOPHYSICS rank: 42 / 87 = 0.483 (2021) - Q2 - T2
Categ. JCR: MINING & MINERAL PROCESSING rank: 8 / 20 = 0.4 (2021) - Q2 - T2
Categ. JCR: MINERALOGY rank: 11 / 30 = 0.367 (2021) - Q2 - T2

Factor impacto CITESCORE: 3.7 - Earth and Planetary Sciences (Q2)

Factor impacto SCIMAGO: 0.522 - Geotechnical Engineering and Engineering Geology (Q2) - Geology (Q2)

Financiación: info:eu-repo/grantAgreement/ES/DGA/E18-20R
Financiación: info:eu-repo/grantAgreement/ES/MCIU-AEI-FEDER/RTI2018-093419-B-I00

Tipo y forma: Article (Published version)

Área (Departamento): Área Cristalografía Mineralog. (Dpto. Ciencias de la Tierra)