Author: dr. sc. TOMISLAV MALVIĆ, red. prof.
Faculty: Sveučilište u Zagrebu, Rudarsko-geološko-naftni fakultet
The recognition of (rock) lithotype is challenging process. It can be done using basic or special geological maps, but is often uncertain process on micro locations. Moreover, the rock photos can be taken using handy or drone cameras what emphasis the problem of their scaling. It is possible to solve using mathematical macros for image analyses incorporated in the ImageJ software. That is necessary to have at least one certain determined sample (of lithology and age) named as prime sample(s). All other samples taken in the vicinity (several square kilometres) belonging to the same geological map sheet can be numerically compared with referent one(s), calculating colour (pixel) differences. The samples from different lithologies (and sometimes ages) will differ more than colourised difference of the same lithotypes. Such analysis is shown here for several samples taken in the Gorski Kotar (the sheet “Delnice), photographed at the Crni Lug (Prapot, dolomites, Upper Triassic) and Lokve (Kamenjak, limestone, Middle Jurassic) localities. The method proven its usefulness and applicability for precise geological determination on the fieldtrips.