Characteristics of fossiliferous deposits

Consequently, bones and teeth in limy deposits are also exposed to corrosive destruction but to a lesser degree. In the case of limy deposits, it is more or less insignificant whether the fossiliferous sediments are loose ones with high porosity (such as sands or loess) or solid rocks (like travertine). Both provide sufficient and favorable conditions for the preservation of human skeletal remains, and this is why finds and sites of paleoanthropological significance are mainly connected with such deposits. In detail, such conditions are shared mainly by the following sediment types:

1. Fresh-water lime deposits (calcareous deposits from inland waters, as a rule consisting of >90% CaCO3, frequently modified by diagenesis and especially to be found in travertines)

2. Loess (dust deposits of eolian origin, characterized by lime content, as a rule between 15% and 30% CaCO3) with dust layers, intercalated by buried soils, frequently with calcareous (and also with decalcified) humus horizons

3. Cave deposits, especially in karstified calcareous mountainous regions, where caves originated from subterranean drainage ways and were occupied by human entry and settlement after drying (which often happened as a result of moving of the original water way)

4. Calcareous debris, especially in mountainous regions, in open-air sites (lime content of the rock detritus being identical to that of the solid rock, perhaps less in the intermediate matter)

5. Calcareous fluvial and deltaic gravels and sands, however preferably containing displaced objects

6. Calcareous lacustrine and beach deposits, as a rule silty and clayey, sometimes laminated

In addition to these site types, those favoring the preservation of soft parts (as in the case of bog bodies) have to be considered, preferably in peat and limnic mud layers.

Moreover, tephras, i.e., pyroclastic deposits traced back to nearby volcanic eruptions—as in the case of Vesuvius during August 79 ad—enable the origination and preservation of human body imprints, which can be replenished by means of gypsum after detection. The method for such a procedure has been applied since the 1860s (since the year 1863 to be precise), first of all by the Italian archeologist Giuseppe Fiorelli who was the longstanding leader of the excavations at the ancient town Pompeii, which was covered by tephra and pumice on the occasion of the aforementioned Vesuvian eruption (Mau 1899). Exceptional finds are the brain endocasts as cited by way of example from the Eemian travertine at Ganovce in Slovakia (Vlcek 1958).

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