Managing and Surveying the Geological Garden at Tata (Northern Transdanubia, Hungary)

摘要

The Geological Garden at Tata is an open-air geological museum where a spectacular succession of Tethyan Mesozoic sedimentary rocks, characteristic of the Alpine-Carpathian region, is finely exposed in abandoned quarries and cleaned rock surfaces. In addition to geological values, the area houses copper-age chert mines, the only ones accessible to the wider public in Hungary. Due to financial problems, however, maintenance of the site was more or less confined to mowing for more than 20 years. Renewal of the Geological Garden began in 2015 when large-scale cleaning as well as detailed surveying was carried out. Removing the soil and loose rock debris provided opportunity to study the effects of weathering and growth of vegetation. Near 60 m(3) of rock debris and soil had been accumulated on approx. 5000 m(2) rock surface over the decades of obligate deterioration. Lower Jurassic marl and Middle Jurassic radiolarite chert beds as well as Middle Jurassic limestones proved to be especially deeply weathered. The cleaning action raised the question whether the sub-horizontal rock surfaces can be conserved for a long time in their present state or not. Lessons drawn from the latter can serve as a basis for future maintenance activities as well as for plans aiming at developing geosites.