Thematic mapping. Thematic map

The purpose of creating thematic and special maps is assessment studies: of living conditions of the population and the impact of climate on health; of agroclimatic conditions and the impact of climate fluctuations on crop yields; of conditions for developing a territory for construction; of recreational conditions of the area.

The main objective of creation or update is cartographic products that correspond as closely as possible to the actual state of the terrain, in accordance with applicable regulatory and technical documents and the terms of reference.

Maps of exploration and field-development areas are needed to identify hazardous geological processes, assess karst hazard, wetlands and waterlogged areas, ravine-gully erosion and potentially hazardous landslide sites.

Depending on the client's requirements, the following may be created: an engineering-geological zoning map, an engineering-geological conditions map with a table of characteristics of identified taxons, a factual-material map, a map of hazardous geological and engineering-geological processes, a map of the degree of karstification and karst hazard, and a schematic map of hazardous geological processes.

Acquisition and analysis of remote sensing materials, georeferencing, orthophotomaps, DEMs and digital thematic materials are performed in-house; fieldwork and chemical-analytical studies — through local partners. Building a DEM helps identify solifluction and landslide formation; interpretation of synthesised orthoimages combined with the DEM details geological processes.

Very high- and high-resolution satellite imagery can be obtained more promptly: it may already be in the operator's archives, and a new survey does not require clearances from the competent authorities. Satellite imagery does not require a site visit, unlike aerial photography and UAV surveys.

Aerial photography provides images with a spatial resolution of up to 1 cm/pixel, a higher level of detail of orthophotomaps and models, RMSE of point coordinate determination of less than 10 cm, and can be performed below continuous cloud cover.

Remote sensing data make it possible to localise potentially hazardous geological sites more accurately, reduce fieldwork, lower the anthropogenic impact on the development area and shorten engineering-survey timelines through coverage and the speed of data acquisition.

Agreement of questions and analysis of the availability of remote sensing data, source map materials, additional and reference data: from 1 to 5 working days. Contract signing: from 1 to 5 working days. Obtaining images: from 3 to 10 days from the date of receiving 100% advance payment for remote sensing materials. Requesting and obtaining source map materials from TsGKiPD (if necessary): from 1 to 20 working days. Creation of digital orthophotomaps: from 5 working days. Interpretation and vectorisation: from 15 working days. Edge-matching of adjacent sheets and performing checks: from 5 to 10 working days. Report preparation: from 5 to 10 days. Total timeline: from 20 working days.

Timelines depend on the number of nomenclature sheets, the scale and type of product, and the availability of archive remote sensing materials, additional and reference materials. Creation of orthophotomaps for interpretation and vectorisation — from 5 working days from the date of 100% advance payment for remote sensing data; interpretation and vectorisation start — from 3 days after orthophotomap production starts.

For preliminary work the following are needed: coordinates of the mapping area; scale and type of map, format, sheet layout, projection, coordinate and height systems; availability of source map materials, additional and reference data; lists of ground-control-point coordinates; requirements for feature composition and attributes; whether editorial and technical instructions need to be prepared.

If this information is not available, it is enough to state the purposes of the maps and the work planned to be performed — specialists will prepare a proposal.

When creating up-to-date thematic maps, topographic maps and plans whose completeness and accuracy match the target scale are used, as well as engineering-geological maps, results of surveys from previous years, and additional and reference materials (including materials from the CGCF, territorial inspectorates of Gosgeonadzor and reference-information systems of other agencies). The map to be updated may be a map from the TsGKiPD collections or a map provided by the client.