RT Journal Article T1 Ostreidos de la Unidad de Sopuerta (límite Aptiense inferior/ superior; Cuenca Vasco Cantábrica): estudio geoquímico y diagenético T1 Oysters of the Sopuerta unit (low /upper Aptian Boundary; Basque Cantabrian Basin):geochemical and diagenetical study A1 Ibisate, Ruth A1 Elorza, Javier AB The realization of geochemical and diagenetical studies on fossil oyster’s shells from the «Calizas Nodulosascon Ostreidos y Limolitas de Sopuerta unit» has allowed demonstrating the variations in the luminescence ofdifferent microstructures, mainly in the Regular Foliated one (RF), as a result of different burial depths. Thestructural properties of the distinguished microstructures made possible, to a greater or lesser extent, thecirculation of diagenetic fluids which provided the shell with diagenetic elements like Fe, Mn or Mg. As aresult of this cationic exchange, the shell enriched the fluids with Na or Sr, considered primitive elements inoyster’s shells. The importance of the rocky matrix in the geochemical alterations has been demonstrated,comparing the results of this study with the results obtained by Higuera-Ruiz and Elorza (2006) YR 2009 FD 2009 LK http://hdl.handle.net/10272/7986 UL http://hdl.handle.net/10272/7986 LA spa DS Repositorio Institucional de la Universidad de Huelva RD 31 may 2026