Application of GIS technologies for engineering geodynamic zoning of mountain territories

. The lack in practise of applying special engineering-tectonic studies in the course of standard engineering surveys does not allow us to fully take into account the features of engineering-geological conditions of mountainous territories.In the work for the section of the Black Sea coast from Gelendzhik to Tuapse, which is part of the Afipsko-Defanovskaya orographic stage, a detailed study of discontinuous structures was carried out using cartographic constructions. The use of the GIS technology tool made it possible to carry out an overlay analysis of maps of morphometric indicators, as well as to draw up a diagram of tectonic blocks. The results showed good convergence with the data obtained earlier on a smaller scale. This provided the basis for zoning the territory according to the degree of favorability of engineering and tectonic conditions with the involvement of morphometric and tectonic features. The study of this territory was conducted for the first time and contributes to the clarification of its neotectonic structure, expanding the scope of application of structural and geomorphological methods based on GIS technologies in engineering and geological research.


Introduction
Intensive developing the Black Sea coast of Krasnodar Krai is inevitably associated with a significant increase in capital construction, but the lack of practice of special engineering and tectonic studies during standard engineering surveys does not allow to fully take into account the features of engineering and geological conditions of the mountain territory. In this connection it is obvious that detection, mapping and estimation of activity of faults are of great importance when choosing routes of linear constructions, sites for industrial and civil construction, when choosing measures for engineering protection of buildings and constructions against dangerous geological processes. Therefore, the study of fault structures, which have orographic expressions, within the framework of evaluation of engineering-geological conditions is important and urgent.
Recently, the tectonics of the faults of the northwest Caucasus has been widely discussed [1][2][3], regional faults are reflected in the corresponding sheets of state geological maps M 1:200,000, but there are no investigations of tectonic structures of a rank allowing their consideration during engineering research. For the territory under study there is experience of GIS-technologies application for evaluation of relief as a factor of dangerous geological processes development [4][5][6]. Nevertheless, to take into account the near-surface tectonic structures in engineering and geological zoning of mountainous areas they are carried out for the first time.

Materials and methods
In the traditional approach to geotechnical engineering zoning, tectonic structures are used only to distinguish the largest taxa -geotechnical engineering regions. Therefore, the structural-tectonic characteristic reflects the most significant differences in the structure of the Earth's crust, associated with a long history of its formation and expressed in a set of sedimentary formations, in the ratio of structural floors and the degree of dislocated rocks [7].
In this paper, we consider a territory of intensive development of the Black Sea coast from Gelendzhik to Tuapse. It belongs to the Afip-Defanovskaya orographic stage bounded in the west by the transverse Gelendzhik and in the east by the Tuapse faults [8]. Thus, the area appears within one large taxon, so to further study its tectonic fragmentation and isolation of tectonic structures of lower rank, structural-geomorphological analysis was applied.
As input data, the publicly available earth radar topography mission (SRTM) was used to obtain information. The following maps of morphometric indicators were analysed: maps of relief dissection density (horizontal dissection), maps of relief dissection depth (vertical dissection) and maps of general relief dissection built according to common methods [9,10]. The identification of fault structures, dividing the regional block into smaller fault zones, was carried out by the MV method. Piotrovsky [11] by comparing the absolute marks of the tops and watersheds. This made it possible to identify hypsometrically isolated blocks or groups of adjacent blocks comparable in scale rank. Judging from the latest relative vertical displacements of the contiguous blocks, the interblock faults are subdivided into very active (with amplitude of 300 m and more from the difference of top marks of the watersheds), active (with amplitude of 200-300 m) and ordinary (with amplitude up to 300 m from the difference of top marks of the watersheds). As a result, separation of different level geodynamic blocks allowed us to carry out zoning of the territory by engineeringgeodynamic feature.

Results
Assessment of the relief through vertical dissection showed that the territory can be divided into 5 categories, characterizing different degrees of intensity and intensity of recent movements (Figure 1). The construction of a horizontal relief dissection map (Figure 2) made it possible to divide the territory into areas with different number of slopes and slope exposures per unit area.  An increase in general topographic dissection from west to south-east can be observed (Figure 3), which correlates well with the increasing complexity of the geological structure and an increase in precipitation in the same direction.  The designed scheme of engineering-geodynamic zoning was compared with the scheme of neotectonic zoning of the North-West Caucasus and adjacent territories [12] and showed good convergence of the obtained results.
Assessment of geotechnical conditions in terms of their favorability for the construction of projected facilities ( Figure 5) [12].

Discussion
The scheme of geodynamic engineering zoning not only does not contradict, but also agrees with the available information, significantly detailing the idea of the tectonic structure of the studied section of the Black Sea coast of Krasnodar Krai (Figure 7).
The proposed approach can be used to map fault zones in the preparation of spatial planning documents and to clarify the tectonic structure of the future construction site for the preparation of site planning documentation and/or the preparation of project documentation.

Conclusion
A leading factor in the formation of the engineering and geological features of the Black Sea coast is the tectonic structures affecting the surface and subsurface construction zone. Differential movements have found expression in the relief not only at the macro block level but also at a lower level.
The largest inherited rupture deformations coincide with the fault lines identified during the M 1: 200000 neotectonic zoning, which in turn coincide with the block structureslineaments identified during the interpretation of aerial satellite images.
The implementation of the proposed preventive studies will reduce costs to assess the impact of tectonic conditions on the conditions of construction and operation of buildings and structures. The results of this work may be in demand by surveyors, governmental agencies and businesses, as they form the basis for spatial planning, selection of optimal engineering survey methods, organization of a monitoring network for hazardous exogenous processes, and assessment of the anticipated risks associated with the presence of active fault structures.
Application of modern technologies in structural-geomorphological analysis using computer processing allows a new approach to solving problems of engineering-geological surveys in mountain-fault areas and construction of various auxiliary schematic maps and the main map of engineering-geological zoning.