General engineering geological characteristics of the Kaštela (Croatia) flysch deposits

Most of the Eocene flysch clastite bedrocks in the wider area of the city of Kaštela near Split are urbanized and densely populated. Northern parts of the flysch terrain are mainly covered with thin rockfall breccia and other slope material originated from the Mesozoic carbonate overthrust nappe. Therefore, there are very lim-ited possibilities for outcrop research. On the other side, in the last several years geotechnical investigations and construction of infrastructural projects enabled us to identify some engineering geological properties and problems of the flysch complex. The obtained facts and numbers will be incorporated into the Basic Engi-neering Geological map of Croatia in the scale of 1:100,000. The flysch in wider area is comprised of limestone breccia, calcirudites, calcarenites, marl, clayey limestones and rarely of large limestone olistolithe blocks. The investigated area is mainly built of marl with local inter-bedding of calcitic siltstone, calcarenite and clayey limestone. In general, lower part of the apparently 800 m thick flysch complex is dominantly built of coarser grained clastites. According to the available laboratory, geophysical, borehole and limited surface data several conclusions can be made. Based on dominant component at least two flysch types can be identified. Marly type of flysch with dominant properties of marl and clay rich marl with rare coarser grained interbeds, is characterized by mil