Читать книгу Monument Future - Siegfried Siegesmund - Страница 213

The detailed petrographic characterization of the Valverde sample highlights some interesting features; the limestone shows a partially recrystallized groundmass, consisting of around 50 % micritic and 20 % of dismicritic components and peloidal microsparit.

Microscopically it is possible to recognize that there are zones (patches) composed of micritic matrix and an other one composed of sparitic cement, giving the rock an inhomogeneous effect similar to bioturbation. All components are smaller than 2 mm composed of bioclasts, pelloids, pseudo-pelloids, benthic foraminifers, echinoderms and several spicules of crinoids. The fabric of the sample varies locally from mud- to grain- supported.

An interesting aspect of this sample is the presence of disturbed areas where parallel microstylolites appear, affecting the groundmass. The microstylolites consist of an opaque material (black) probably accumulations (laminaes) of organic material and clays.

According to Flügel (2004) this limestone belongs to the RMT 14, Bioclastic packstone and wackestone with skeletal grains, various amounts of intraclasts and some ooids (shoal-near). These sediments are common for the open marine, inner ramp zone.