Investigating possible correlations between the porosimetry and insoluble residue content of Malta’s Lower Globigerina Limestone

Proposal for the nomination of Lower Globigerina Limestone of the Maltese Islands as a “Global Heritage Stone Resource”

“…It is on the basis of these criteria, which will be further discussed below, that the Lower Globigerina Limestone is being proposed for nomination as a GHSR by a working group (authors) within the University of Malta, where research on the stone has been conducted for the last 30 years; this research covers geochemical, mineralogical and petrographical studies, as well as the determination of physical and mechanical properties (Bianchi, 1975;Cachia, 1985;Bonello, 1988;Zammit, 1989;Saliba, 1990;Farrugia, 1991;Sammut, 1991;Xuereb, 1991;Cassar, 2002Cassar, , 2004Cassar, , 2010Cassar and Vella, 2003;Rothert et al, 2007;Cassar et al, 2008;Diana et al, 2014;Zammit and Cassar, 2017) -data given in Table 1 (below). This paper will also be utilised as the main vehicle to provide the data as required by the Checklist for "Global Heritage Stone Resource" Designation (revised October 2014).…”

“…Whereas many of the types of "franka" stone are generally reputed to weather well, stone obtained from the various types within the "soll" facies is alleged to be less durable and will deteriorate in a few years, depending on exposure. The two extreme ends of this scale of variations of Lower Globigerina Limestone have been found to differ in geochemical and mineralogical composition, and also in physical properties (Cassar and Vella, 2003;Zammit and Cassar, 2017). The causes of deterioration have been recognised to be the intrinsic properties of the material, as well as environmental causes, including temperature changes, wind, sun, humidity, pollution and the presence of soluble salts (Cassar, 2002).…”

“…Globigerinid biomicrites, biomicrosparites, wackestones and packstones, pale yellow to cream in colour, medium to fine grained, massive, bioturbated limestone characterized by a uniform texture (Pedley et al, 1976;Baldassini and Di Stefano, 2017 (Cachia, 1985;Bonello, 1988;Saliba, 1990;Sammut, 1991;Xuereb, 1991;Farrugia, 1993;Tampone et al, 1994;Cassar and Vella, 2003;Cassar, 2004;Rothert et al, 2007;Cassar et al, 2008;Diana et al, 2014;Zammit and Cassar, 2017). …”

Petrophysical Properties of Limestones - Influence On Behaviour Under Different Environmental Conditions And Applications

“…). Impurities as clay minerals decrease the strength and cause sudden changes in the microporous network characteristics and consequently turns variable the durability of the building stone(Tugrul and Zarif 2000;Jensen et al 2010;Zammit and Cassar 2017).The chemical composition of the studied limestones is very similar, with small differences (Table2). The VAV limestone stands out showing a high quantity of magnesium and dolomite.…”

“…Obtained values of porosity, bulk density, matrix density and capillary water absorption (CWA).The values of porosity show a wide range, from 0.11% in LIOZ limestone to 18.80% for the SBM variety, re ecting the span of rock types and related textures. These values of porosity are only valid for the studied samples and can be used as an approximated value for the limestone varieties since changes in the microporous network characteristics with depth of extraction have been reported(Tugrul and Zarif 2000;Zammit and Cassar 2017). Some varieties extracted in the MCE were…”