Geology Reference
In-Depth Information
Lithology. Limestone? Dolomite? Marly limestone?
Cherty limestone?
In the case of quarries located within major strati-
graphic units, the chemical composition (e.g. SiO 2 -
Al 2 O 3 -CaO plots) and the occurrence and distribution
of minor and rare elements allow, together with thin-
section criteria building stones to be attributed to spe-
cific source areas (Harrell 1992; Klemm and Klemm
1973).
A combination of textural, geochemical and petro-
physical criteria (water absorption, ultrasound trans-
mission velocity, porosity, density and compressive
strength) has been successfully applied for locating
ancient quarries used for constructing historical build-
ings (Galán et al. 1999).
Sedimentary structures. Massive limestones or in-
dications of bedding? Cross-bedding structures?
Reef limestone?
Microfacies. Matrix-dominated or grain-dominated
limestones? Mud-support or grain-support? Dun-
ham-classification types? Dominating grain types?
Paleontological criteria. Dominating fossils (e.g.
shells, foraminifera, calcareous algae). Fossils that
give indications of paleoenvironment and age.
Sedimentary fabrics. Biofabrics, lamination, burrow-
ing, fenestral fabrics, birdseyes, nodular fabrics, dis-
continuity surfaces.
Diagenetic features. Cement, recrystallization, di-
agenetic fabrics (compaction, stylolites).
19.2.2 Building Stones: Examples
These criteria or at least some of these criteria will
characterize facies types that can be compared with
facies types of adjacent outcrops and ancient quarries.
Many ancient buildings used material from domestic
sources, but also preferred specific materials, often ex-
ported from far distant regions. That is true particu-
larly of marble (see Sect. 19.6).
There are many examples relating materials used as
building stones to potential or proved source areas, but
rather few investigations based on the differentiation
of limestones in relation to facies criteria.
The following examples demonstrate how detailed
studies can contribute to answering specific archaeo-
logical questions.
Fig. 19.1 Building stones of the giant outer wall of Hattusa , the capital of the Hittite reign. The blocks of the wall are
limestones, particularly reddish coral limestones. Especially the stones in the lowermost row show abundant reef corals.
Microfacies and paleontological criteria prove that the material used was derived from Early Cretaceous limestones outcrop-
ping in and near Hattusa. The width of the largest block in the center is 80 cm. Bogazkale about 150 km east of Ankara,
central Anatolia, Turkey.
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