Informativity of borehole geophysical methods in choosing the location of the main structures of the hydroelectric power plant (HPP)
Keywords:vertical seismic profiling, seismic sounding, seismotomography, rock safety, zonal rock massifs
To study the state of the rock massif on the territory of the HPP on the river Vele (Republic of Equatorial Guinea) geophysical surveys using vertical seismic profiling, inter-well seismic survey and inter-well seismic tomography are performed. On the basis of the data obtained, there are significant differences in the state of crystalline rocks on the left-bank and right-bank sections of the dam construction. On the right-bank part of the territory, rock is more secure (about 90 % of the inter-wellbore space under study is characterized by a longitudinal wave propagation velocity (VP) of more than 4,500 m/s. On the left bank, for approximately 70 % of the investigated soil thickness VP is more than 4,500 m/s. The rock safety index allowed to obtain a rapid assessment of the state of the rocks in the massif, the rock was divided into four subzones: A — very strong unloading effect with the disintegration of rocks to eluvium, B — a strong manifestation of unloading and weathering, C — a weak manifestation of surface weathering and a moderate Manifestations of unloading, D — rocks are almost non-weathering, there are only signs of linear weathering in subvertical tectonic disturbances and large cracks. According to the results of the inter-well seismic tomography performed, it is also established that the more disrupted rocks are characteristic of the left-bank part of the construction site. Taking into account the obtained data, the plan for the location of the main structures of the dam of the hydroelectric power station is clarified.
Hydroelectric power station Senje on the river. Vele in the Republic of Equatorial Guinea. Vol. 3. Book 2. Technical report on the results of field geophysical studies, 2013. Kiev: State Enterprise "KIIZI EP", 50 p. (in Russian).
Zinchenko V. S., 2005. Petrophysical fundamentals of hydrogeological and engineering-geological interpretation of geophysical data. Moscow: AIS Publ. House, 392 p. (in Russian).
Integrated engineering and geophysical research in the construction of hydraulic structures. Eds A. I. Savich, B. D. Kuyundzhich. Moscow: Nedra, 1990. 462 p. (in Russian).
Methods of compiling geostructural patterns (models) of rock massifs in the foundations of hydroconstructions: the manual for SNiP. 2.02.02-85. Leningrad: VNIIG Publ. House, 1991. 163 p. (in Russian).
Onishchuk I. I., Vyzhva S. A., 2017. Express assessment of the structure of the geological section of the territory of he location of hydropower stations by geophysical methods. Vestnik Kiyevskogo universiteta. Geologiya (76), ...—... (in Russian).
How to Cite
Copyright (c) 2020 Geofizicheskiy Zhurnal
This work is licensed under a Creative Commons Attribution 4.0 International License.
Authors who publish with this journal agree to the following terms:
1. Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
2. Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
3. Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).