Naslov
The significance of structural and geological relationship assessment in the construction of the Ombla underground hydroelectric power plant

Autori
Buljan, Ranato ; Prelogović, Eduard

Izvornik
Rudarsko-geološko-naftni zbornik (0353-4529) 9 (1997); 17-22

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
structural fabric; tectonic movements; undurground hydroelectric power plan; Ombla; Dubrovnik

Sažetak
The construction design of the underground hydroelectric plant Ombla required geological and structural investigations to be carried out. Due to past earthquakes in the area permanent tectonic movements were inferred. Therefore, in the wider and adjacent surroundings of the Ombla spring it was necessary to analyze the structural fabric and the geodynamic characteristics of the area. The most active zone encountered is the front part of a thrust fault belonging to the Dinaricum regional structural unit. The compressive regime is maintained as a response to the regional stress of an approximately S-N orientation. Different displacements of various parts of the Dinaricum unit are present. Along the rim of the structural blocks, the Hum-Ombla fault zone extends, accompanied by left transcurrent faults. Through this zone the main groundwater drainage occurs supplying the Ombla spring. In the local Ombla spring area this zone is characterized by three sub-blocks and three major faults. The most important fault for the vital facilities of the Ombla hydroelectric power plant is the Pločice fault which divides the structural sub-blocks. Along this fault zone there are four mutually connected. The lowest two are active groundwater draining systems supplying the Ombla spring. The data on local stress implies the following deformation of sub-blocks : sub-blocks 2e and 2f are displaced along normal faults from 20* to 30* to the left, downwards, while the sub-block 2 d is displaced along the Pločice thrust fault of 100* to 130* to the left, upwards. The structural data confirmed that the building of an underground dam with a height from 100 to 130 m was feasible. The connection between the caverns and the fault zone was determined. The unfavorable position of the active Pločice fault zone imposes the construction of vital Ombla power plant facilities underground.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

POVEZANOST RADA