Those deposits suffered mlechanical erosion or partial solution in atmospheric conditions after which the remaining particles has been transported and accumulated in nearby depression. Apparently, the origin of clasts includes lateral (upslope) existence of travertine crusts. Particles strongly suggest primary bioticaly and abiotically precipitated calcareous deposits. The remainder interlayers is represented by yellow-white sand-sized lithoclastic lithotype L-4. Intercalation of L-2 and L-3 lithotypes suggest that the deposition was changing between more-or-less dry vegetated flats and shallow still pools.

Abundant presence of rafts, precipitated at the water surface of still pools, creates delicate, porous « foamy» younger layers of lithotype L-3. Between the plant molds paper-thin rafts are accumulated reflecting crystallization at the surface in shallow stagnant water. Plant stems were incrusted by sparry calcitic, arboresced or ray shaped crystals. Subsequent deposits represent incrustation of higher plants, possibly reeds, which resulted in thick-bedded, porous lithotype L-2 pointing to rain-diluted and cooled waters from the hot spring. Microbial laminae, as well as faint pizoid « ghosts», suggest bioticaly influenced precipitation in rather shallow depression with occasional subaeral conditions. At the base of travertine succession thin, dense, laminated sediments of lithotype L-1 occurred. Precipitation, occurred some distance SE from spring, covering the abandoned Roman buildings and filling depressions. XRD analysis shows simply calcite as constituent mineral. These deposits were considered downslope precipitates of the thermal spring run-off waters influenced by the surface water dilution but with overall travertine characteristic. As they covered the floor of basilica, the age of the succession was estimated to no more than 1600 years. Latest archaeological research of the Roman basilica, performed in 2004, showed that slightly downslope, above the basilica floor, 3 m thick sediment succession occurred. Water that spilled over was in Roman times drained to the south. This consists of the baths (thermae), basilica, Capitoline temples and the forum with the stone-built pool where the sulphur-rich thermal water springs out. Thanks to the archaeological excavations and research, at the uppermost terrace of the settlement, an area (ca 6000 m² ) with Roman architectural remains has been uncovered. The present-day town and spa of Varaždinske Toplice (Northern Croatia) was in the 1st-4th centuries AD the site of the Roman settlement - Aquae Iasae.

Aquae Iasae by Kušan Špalj, Dora