Bjelovarska subdepresij a, kao geološki određen prostor, sadrži – uz dokazane rezerve ugljikovodika – i njihove potencij alne rezerve te rezerve geotermalne energij e. Dan je pregled pridobivanja i uporabe takvih energenata, a zatim sastav, dubina i rasprostranjenost takvih ležišta u dij elovima gdje su istraživana i pretpostavljena. Geotermalno ležište izučavano je u prostoru mezozojskih karbonata te donjomiocenskih i srednjomiocenskih krupnih klastita u sinklinali Velika Ciglena, najvećoj pojedinačnoj strukturi u subdepresij i. Dokazano je postojanje termalne vode na dubinama od oko 2.500 m, no do danas nij e privedena pridobivanju na površinu i uporabi bilo za proizvodnju struje bilo za grij anje. Nekonvencionalna ležišta također su pretpostavljena u tom istom prostoru, unutar gornjobadenskih, sarmatskih i donjopanonskih matičnih stij ena, koje su dostigle termalnu zrelost. No, takvih ležišta, posebice plina, moglo bi se naći i na rubu subdepresij e, u Bilogorskoj zoni, unutar struktura gdje nisu dokazana konvencionalna ležišta ugljikovodika (Cremušina, Gakovo), no opažene su pojave plina i naft e u slabopropusnim pješčenjacima gornjega miocena.The Bjelovar Subdepression is geologically very well defi ned area where are discovered proven hydrocarbon reserves. However, there are assumed as well potential hydrocarbon and geothermal reserves. Here is fi rstly given review of forming and application of fossil fuels and geothermal energy. It is followed by review of lithologies, depths and distributions of unconventional and geothermal reservoirs in subdepression parts where they are explored and assumed. Geothermal reservoir is studied in Mesozoic carbonates and Karpatian to Badenian coarse grained clastics in Velika Ciglena Syncline. It is the largest single structure in Velika Ciglena Syncline, where is proven geothermal water at depth more than 2500 m. However, it still is not proven and used for electricity of thermal applications. Unconventional hydrocarbon reservoirs are also assumed in the same area, i.e. in Upper Badenian, Sarmatian and Lower Pannonian sediments in the thermal mature phase. Also, such unconventional reservoirs, especially of gas, could be proven at subdepression margin, in the Bilogora Zone, in structures where conventional reservoirs are not proven (Cremušina, Gakovo), but are registered oil and gas shows in weakly permeable Upper Miocene sandstones
