Geophysical map of Ukraine
The map of anomaly magnetic field
The map of anomaly magnetic field demonstrates anomaly magnetic field of Ukraine which is reduced to a single level with the help of special supporting grid. A map is compiled based on the results of ground and aeromagnetic surveys. Homogeneous precision aeromagnetic survey enables comparing the nature of the magnetic fields at different geological regions and identifying general patterns in the distribution of anomalies in Ukraine.
Anomaly magnetic field varies in its positioning, size and shape. The intensity of additional anomalies varies mostly from 100 to 1000 nT. Only few anomalous zones in the areas of iron ore formations reach 2000 – 4000 nT and more. A negative field does not exceed 500 nT. As for configuration contour and values the field anomalies are divided into three main types: linear, isometric and almost "no anomaly." The most common linear anomalies have different size and orientation. The direction and shape of anomalies are consistent with the stretch of the main geological structures of the regions. Linear anomalies sometimes extend for tens and even hundreds of kilometres. They usually portray the boundaries of the geological structures and disjunctive dislocations.
Nature of magnetic anomalies is associated with the composition of the given rock type and contained ferruginous minerals. The presence of positive magnetic anomalies indicates that the crystalline base rocks is dominated by intermediate and basic rock types. The negative and marginally positive fields correspond to non-magnetic and low-magnetic complex formation of sedimentary and igneous rocks of acid composition. Sedimentary cover, which is non-magnetic, does not alter the picture of the field or does not prevent a trace of submerged structures foundation.
The nature of the magnetic field in the regional plan reflects major geological structures. This is primarily Middle-European platform and area of its folded frame.
Within the platform, crystalline rocks of Ukrainian shield and Voronezh crystalline massif are mapped.
The magnetic field Ukrainian shield characterized by a large variety of shapes and differentiation anomalies. The area of Kryvorizko-Kremenchug magnetic anomalous zone is characterized by intense anomalies observed at sub-meridian stretch coinciding with areas of ferruginous-siliceous formations. Similar pattern is observed in Kiev area magnetic field (Yadlivsko-Trahtemyrivska zone). Both of these zones have a broad band (150 km) of mainly negative fields while their meridian direction crosses the entire Ukrainian shield. Ukrainian shield is distinguishable from Voronezh crystalline massif to Dnieper-Donetsk cavity. In the central part of Dnieper-Donetsk cavity there are two large regional additional anomalies distinguishedat the generally neutral negative magnetic field level (0 to 200 nT) negative field clearly distinguished two regional positive anomaly. Its nature is probably related to Devonian effusive rocks of the basic content.
The southern slope of Voronezh crystalline massif is clearly mapped Kursk Magnetic Anomaly, which is located mainly outside Ukraine. The boundaries of the Middle-European platform areas are well traced though the nature of anomalies is changing. Thus, the anomalous magnetic field, traced by uniform surveys throughout territory of Ukraine, allows capturing the main geological structures and is used to determine the nature of their joints, as well as for the for mapping of their internal structure.
The regional gravitation map
Most of the territory of Ukraine (Ukrainian shield, Volyn-Podolsk plate, the Black Sea basin and Dnieper-Donetsk cavity) is characterized by positive anomalies of the gravitational field, whereas in case of Vinnitsa and Zaporozhyeareas the high level of gravity is explained by the rocks of high density, including the rock bottom of crust, and Chernigiv (Chernihiv basement) Prilutsky (central part of the Dnieper graben) Golovanevskiy (Kirovograd block) and Volyn (Korostens'kyi Pluto) gravity highs. Negative anomalies of the gravity field describing in-depth distribution of thinning rocks in the earth's crust, including the сonsolidated ones are mapped within the Ukrainian Carpathians (Ivano-Frankivsk minimum), the southern slope of Middle-European platform (Kharkiv minimum) in Indolo-Kuban deflection (minimum Kerch), and several local minimum of gravity – the Ukrainian shield (Ovrutskyy, Kirovograd) and in the northern Black Sea coast (within suture zones). Thus, the map of regional gravity field (including the impact of the local gravitational field) essentially reflects the in-depth distribution anomaly creating geological objects within the earth's crust.
For more detailed information please contact:
Avtozavodska 78-A, Kyiv, Ukraine, 04114
Telephone: +380 (44) 430-70-24, 430-41-76
e-mail: [email protected]