Madaras László – Szabó László – Tálas László szerk.: Tisicum - A Jász-Nagykun-Szolnok Megyei Múzeumok Évkönyve 8. (1993)
Sümegi Pál: A jászfelsőszentgyörgyi szunyogos felső-paleolit telephely üledékföldtani és sztratigráfiai elemzése
tsz.fm. — NNW 111 -i 110 109 — 108107106105104103Fig. 1. Sedimentary environment of the sand hummock which 1. ábra A jászfelsőszentgyörgyi felső-paleolit telephelyet bethe Upper Paleolithic site Jászfelsőszentgyörgy embedded in 1. sediments of alluvial fan 2. drift sand dune (sand hummock) 3. loessy sediments covering drift sand dune 4. recent soil level + height above sea level ágyazó garmadabucka üledékes környezete. 1. Folyóvízi hordalékkúp üledékei 2. Futóhomokbucka (garmadabucka) 3. Futóhomokbuckát fedő löszös üledékek 4. Recens talajszint fluvial channel deposit (Table I.) at some 1 km to the W of the site demonstrates that at the end of the Middle Wurm the ancient channel of the river Zagyva was near the investigated region. Both granulometric composition and microscopic analyses (Tables II. and III.) prove that there is a genetic connection between the load material of the Ancient Zagyva and the sediment material of the sand dune. Namely, the quartz grains originated from the alluvial fan are sharp with splittery surface, their shape is not really rounded in either of the samples. The reason of this is that before their deposition the grains went through a transportation of only very short duration (Cailleux, A. 1952). Also scanning microscope investigations corroborate this theory (Table II.), namely the quartz grains belong to that type of grains of parent rock origin which went through a short transportation (Krinsley, D.H. - Doornkamp, J.C. 1973). Mechanical damage caused by fluvial transportation is clearly visible on the surface of the grains. (Table II.) The most probable provenance of this alluvial fan material which went through a short transportation is the Mátra Mts., which is relatively near (some 60 km) the investigated area. From there the load material had to cover only a short distance there fore roundness values are smaller. From the viewpoint of roundness the alluvial fan material of the Ancient Zagyva is highly similar to sediments of the Nyírség sandy area (Borsy Z. 1974, 1977), but differs from the wellrounded material of the alluvial fan in the DunaTisza Interfluve area /Duna-Tisza köze/ (Molnár B. 1961, Borsy Z. 1977). The investigations made on the quartz grains of the sand dune at the top of the alluvial fan yielded nearly the same results as the analysis of the fluvial sediment. In drift sand also angular grains originated from the parent rock and gone through a short transportation are predominant 64
