RADIOLARIT MINTÁK VIZSGÁLATA IONNYALÁB ANALITIKAI MÓDSZEREKKEL
INVESTIGATION OF RADIOLARITE SAMPLES BY ION-BEAM ANALYTICAL METHODS

Summary/Abstract: The petroarchaeological research of the past few years could demonstrate the special importance of radiolarite among the raw materials of prehistoric (mainly, chipped) stone tools in Hungary. Radiolarite belongs to the group of sedimentary siliceous rocks. As the name indicates, it is formed of Radiolaria (Fig. 1), i.e., the skeletal elements of siliceous unicellular beings. Apart from siliceous sponges and diatoms, Radiolaria are the most important biogene sources for the formation of sedimentary siliceous rocks. They are present in the seas and oceans since at least the Palaeozoic period. Typically, they form only a small fraction of the fauna, even the microfauna and they disappear unnoticed among the multitude of organic and mineral components forming the marine sediments turning to well-known sedimentary rocks by way of diagenesis. They are very small, typically in the range of 10–100 μm. Radiolaria are accumulated in rockforming quantities only among very special circumstances. For this, deep and cold water is ideal where other marine fauna is scarce and the temperature of the water prevents the accumulation of carbonic rocks. Being small in size radiolarite accumulates from radiolarian silt very slowly, by a rate of some centimeters per million years. The mass occurrence of Radiolaria in the present day Carpathian basin and formation of radiolarite took place in the Mesozoic period when the world ocean (Tethys) was of equatorial position. Radiolarite was formed in a long, west–eastern arch along the Alp–Carpathian system, across the Balkans till the Himalayas. The resulting siliceous rocks can be found at many places in south-central Europe. Our study concentrates on radiolarite within the Carpathian Basin: sampling points are presented on map .

• Details
• Contents