Utilization of archive geophysical data for geodynamical studies in the Sudetes: Example of Bela fault zone (the Nizky Jesenik Mts.).

Acta Geodyn. Geomater., Vol. 16, No. 3 (195), 281–291, 2019 DOI: 10.13168/AGG.2019.0024 journal homepage: https://www.irsm.cas.cz/acta ORIGINAL PAPER UTILIZATION OF ARCHIVE GEOPHYSICAL DATA FOR GEODYNAMICAL STUDIES IN THE SUDETES: EXAMPLE OF BĚLÁ FAULT ZONE (THE NÍZKÝ JESENÍK MTS.) Lubomil POSPÍŠIL1, 2) *, Jiří OTAVA 3) and Eva HUDEČKOVÁ 3) 1) Institute of Geodesy, Faculty of Civil Engineering, Brno University of Technology, Veveří 95, 602 00 Brno, Czech Republic 2) Department of Geological Engineering, Faculty of Mining and Geology, VŠB-Technical University of Ostrava-Poruba, Czech Republic 3) Czech Geological Survey, Division of Informatics and Geological Division, Leitnerova 22, 658 69 Brno *Corresponding author‘s e-mail: [email protected] ABSTRACT Geophysical data are used not only, in geological mapping, exploration of mineral resources, hydrogeology, but are also important for other branches such as environmental protection, civil engineering and archeology. That is why, within the project CzechGeo/EPOS (www.czechgeo.cz), geophysical data access is solved as a separate topic under the guidance o f the Czech Geological Survey (hereinafter CGS). In accordance with the current needs of national and international activities (INSPIRE, EPOS, IAGA), an inventory of available data, its consolidation and harmonization according to national and international standards is conducted. The aim is to store securely and permanently valuable data, which in many cases cannot be reinstated. On the example from the Nízký Jeseník Mts. possible advantages and utilization of Archive dat a for mapping and verification of the movement tendencies gained from GNSS networks – EPN, EAST SUDETEN and MORAVA are demonstrated. Very valuable information for the interpretation of structural and tectonic conditions is provide d b y geophysical data (seismic reflection profiles, gravity and magnetic data, etc.) in the area o f interest, especially in terms of monitoring the main fault systems and the character of the basement structures. ARTICLE INFO A rticle history: Received 31 January 2019 Accepted 20 June 2019 Available online 30 July 2019 K eywords: Recent vertical movements GNSS networks Geophysics Bělá fault Reflection seismic systems and on characteristics of the basemen t structures. GEOLOGICAL SETTINGS The area with the most intensive recen t movements tendencies (Fig. 1) is located in the Moravian-Silesian part of the European Varisca n orogen; more precisely of its youngest Culm facies (D-LC), easternmost part. Geographically it belongs to the Nízký Jeseník Highlands and geologically an d stratigraphically to the Lower Carboniferous (Viséan) sequence of so the called Culm facies. Generally the western parts of area are composed of prevailing p elitic turbidites, while greywackes prevail in the eas t (Fig. 1). The Culm facies sediments tectonicall y overlie those of the Devonian carbonate facies as proved by the borehole Potštát 1 (Čížek and Tomek, 1991). Let us summarize the present state of knowledge, especially that one concerning structural geology an d thermal history. Since the evaluation of seismic reflection profiles and the borehole Potštát-1 (Číže k and Tomek, 1991) the model of thin-skinne d southeasterly tectonic transport within the fold-andthrust belt has been accepted. Most recent wor k regarding thermal history of the Culm basin (Jirman e t al., 2018) brings about a model based on study of the Culm facies (D-LC) vitrinity reflectance in surface INTRODUCTION Using an example from the Nízký Jeseník Mts. we demonstrate a successful usage of geophysical Archive data in mapping and verification of recen t crustal movement tendencies that follow from data gained within the EPN, EAST SUDETEN an d MORAVA GNSS networks. The area unde r discussion is covered by these three geodetic networks that monitor long-term recent Earth’s surface movement tendencies in northern Moravia. The monitoring results of approx. 20 years lead to a conclusion of significant horizontal dextral displacement tendencies that are concentrated along the Bělá fault system (Buday et al., 1995 – Fig. 1). The continuation of the latter towards the NW is associated with the Marginal Sudetic Fault. In the paper, we aim at showing of this structure verification of the results of the GNSS monitoring. Another aim is to calculate the possible depth level o f the source generating the observed tectonic motions. Highly valuable information is additionall y provided by geophysical data (seismic reflection p rofiles, recent vertical movements (RVM), earthquake foci IEP MU, GRAV/MAG data, etc.). The main goal of the paper remains interpretation of structural and tectonic features an d their recent dynamics in the area of study, base d mostly on data from the monitoring of the main faul t Cite this article as: Pospíšil L, Otava J, Hudečková E.: Utilization of archive geophysical data for geodynamical studies in the Sudetes: Example of Bělá fault zone (The Nízký Jeseník Mts.). Acta Geodyn. Geomater., 16, No. 3 (195), 281–291, 2019. DOI: 10.13168/AGG.2019.0024 L. Pospíšil et al. 282 Fi g . 1 Map of the Culm area with location of the Bělá fault system, complemented by recent earthquake data (1996 to 2017 – Sýkorová et al., 2018). Explanations: NNeogene, D-LCDevonian – Lower Carboniferous, violet color – neovolcanics, 1Šternberk-Horní Benešov tectonic zone and magnetic data, seismic reflection profiles) • Catalog of Earthquakes (Institute of Physics o f the Earth, Masaryk University (IPE MU), USGS)) • GNSS data from available networks (Švábenský et al., 2012; Pospíšil et al., 2017; Kaplon et al., 2014) • Recent vertical movements data (Vyskočil, 1996) Archive Data - The geophysical database of the CGS, department GEOFOND includes the results o f geophysical measurements (surveys) in the territory o f the Czech Republic, which was mostly taken by the former Geofyzika Brno company from state budge t funds from the end of World War II to the end o f 2003. Now, they are mostly updating new data fro m airb orne measurement and gravimetric mapping p rojects financed mainly the Ministry of the Environment of the Czech Republic (hereinafter MŽP ČR). Since 2018, as part of the CzechGeo/EPOS p roject, this data will be gradually made available through map applications. D ATA USED FOR VERIF I CATION AND R EINTERPRETATION One of important tasks was to verify the movement trends. Suitable data and criteria were and borehole (Potštát-1) samples. The suppose d maximum paleotemperatures calculated were 260 – 285 ºC for paraautochtonous limestone sequences an d 310-400 ºC for tectonically overthrusted sediments o f the Culm facies. The estimated p rimary thickness o f a sedimentary pile of the Culm facies rocks corresponding with the measured vitrinity reflectance, and thus the calculated paleotemperatures, exceeds 7 km. According to Jirman et al. (2018) the maximu m thermal maturity of the flysch de p osits was aquire d p rior to the Variscan overthrusting, i.e. before 325 Ma. The Devonian carbonate complex reached its maximum thermal maturity already after the overthrusting of the partly eroded flysch sequence before 320 Ma. METHODOLOGY AND PROCESSING We used the following data processing, verification and analysis techniques to evaluate movement tendencies and their interpretation: • Processing of an archive data from CGSGEOFOND Prague database (geological maps, wells and geochemical data, seismic reflectio n p rofiles in SGY versions, radiometric map of the Czech Republic (Manová and Matolín, 1995)) • Geophysical data of Geofyzika a.s., Brno (gravit y Culm facies (DLC) Culm facies Foredeep (N) 1 1 UTILIZATION OF ARCHIVE GEOPHYSICAL DATA FOR GEODYNAMICAL STUDIES IN … . 283 tectonic problems can be followed in the Magnetic map processed by Oasis Montaj SW. Seismic Data - The map layer “the Seismic reflectio n p rofiles” shows only those reflective seismic profiles that have been registered with digital seismic apparatus, and seismic data has been stored either i n the SEG-Y international format or in the corporate CGG format. This condition is fulfilled by reflective seismic profiles from 1971 to 1994, which were measured and processed by the former compan y Geofyzika Brno from the state budget. Access to own seismic data, either in digital format (SEG-Y or CCG format) and raster forma t (tiff), is only possible with the consent of the Department of Geology of the Ministry of the Environment of the Czech Republic, as the owner o f the data. For commercial customers, "lending" is tie d to the existence of a reconnaissance territory and is charged. The results of other seismic measurements, such as refractive seismic profiles (regardless of type of registration) and reflective seismic profiles wit h analogue registration, are not included in the map layer "Seismic reflection profiles" and are onl y available in the form of archival reports. There is p ossibility to attach a layer of seismic well logs measured on the boreholes near the reflection profiles, but these do not exist for our area. Figure 4 shows the reflective seismic profile used 7A/84. This profile intersects almos t perpendicularly the southern part of Bělá fault zone. collected and interpreted to prove faults within the studied area and to explain their character an d kinematics. Geomorphological studies and dat a (Roštínský et al., 2013; Grygar and Jelínek, 2000) completed with geophysical data of sufficient aerial extent were involved to submit the geological model. GEOPHYSICAL DATA Gravity Data - A detailed gravity map of Complete Bouguer anomalies, compiled for a reduction density of 2.67 kgdm-3, on a scale of 1:25 000 for the entire Czech Republic, does not provide more detaile d information about the NW-SE tectonics. The main structural units of the Silesia and the Culm area wit h their effects can be observed from the presented map (Fig. 2) and give the size of individual anomalies, the y can be judged by their powers. Horizontal gravit y gradients or vertical density interfaces (Linsser, 1967) dominate mainly N-S and NE-SW directions. That's why we used gravity maps for verification at least. Magnetic Data - Magnetic map of ΔT anomalies o f the Czech Republic has been compiled on the b asis of measurements made with airborne p roton magnetometer with digital registration at 80 m above the terrain surface (aprox. 55 % of the CR area), distance of flight lines - 250 m, p erio d measurements form 1974 to 2004 (Gnojek et al., 2000). Final version of map of anomalous field delt a T of the Czech Republic were processed for epoc h 1981 (Fig. 3). All above discussed geological and Fi g . 2 Demonstration of combination of the Map of Complete Bouguer anomalies, compiled for the reduction densit y 2.67 kgdm-3 archived in GEOFOND Database with the derivated map of Verticaal density boundaries (Linsse r indications of density contacts). The contour interval is 21 mGal. The Linsser indications represent spatial an d material characteristics of density contact, approximating it by a vertical fault model (Linsser, 1967). The intensit y of the Linsser indication is given by the product E × C, where E is the amplitude of the gravity effect and C is the coincidence between the observed gravity anomaly and the gravity effect of the fault model. Black line segments show the positions of density contacts at the depth of 1 km. mGal L. Pospíšil et al. 284 Earthquakes Foci - The available earthquake foci come from the worldwide USGS Earthquake Catalog and regional earthquake catalogs by the Institute o f Physics of the Earth at the Masaryk University in Brno (IPE MU, incl. events recorded by Sýkorová e t al. (2018) and the Institute of Geophysics of the Czec h Academy of Sciences (IG CAS). In the Nízký Jesení k Mts., the earthquakes commonly reach a local magnitude (M) of 1–3 with estimated depths of ~1 – 12 km at W from the Šternberk – Horní Benešov faul t system and depth 14 – 24 km on the E of the Cul m area. Earlier, the illustration and interpretation of the earthquake epicenters and hypocenter depths were collected for the regional maps (Kárník et al., 1984a, 1984b; Schenková and Kárník, Eds., 1985), in case o f known historic macroseismic fields supplemented with an estimation of asymmetric seismic energ y attenuation related to local tectonic structures (Procházková and Kárník, 1978; processed after the methodology by Schenk et al., 1989), and in some p laces also with calculated focal mechanisms (Havíř, 2004; Špaček et al., 2015, 2006). GNSS Data on Moravia Territory (EPN, MORAVA, EAST SUDETEN, CZEPOS) - Results o f the mapped horizontal movement tendencies of the N orthern Moravia area offer in the recent p eriod the following GNSS networks: Epoch geodynamic networks: • SNĚŽNÍK • MORAVA • EAST SUDETEN, Fi g . 3 Map of magnetic anomalies ΔT (the difference between the measured magnetic field inductance value and the IGRF field reference value for the epoch 1981.0). Map is complemented with recent earthquakes epicentres (yellow stars (Sýkorová et al., 2018)) with magnitude values (M - red) and estimated depths of the hypocentres (blue). • HIGHLANDS Permanent networks: • EPN, CZEPOS, VESOG, GEONAS (public an d research networks), • TOPNET, VRS Now Czech, GEOORBIT (commercial private networks) For the analyses of the area of interest the MORAVA, EAST SUDETEN and CZEPOS networks were used, only. Data were processed from time period/interval mentioned bellow. The existing epoch geodynamic networks are characterized by many common features, notably b y a careful selection of point locations in terms of the optimal observation conditions and assumed tectonic p henomena. The effort to stabilize sites embedded in the rock substrate or stable objects with a fixed base, allowing for forced centring of the receiving antennas, is also important. It has been desirable to use unmodified instrumentation at individual points. Overview of position of all GNSS networks points is in Figure 5 and the brief characteristics of the individual networks are as follows: • SNĚŽNÍK – b uilt in 1992 in cooperation betwee n two academic institutions: Wroclaw University o f Environmental and Life Sciences (PL) and Brno University of Technology (CR). Its basic researc h results were presented by Švábenský et al. (2012); • MORAVA – larger network established in 1994 under joint research activities of the VŠB – Technical University of Ostrava and Czec h Technical University in Praha to study tectonics of crustal structures in the Bohemian Massif – UTILIZATION OF ARCHIVE GEOPHYSICAL DATA FOR GEODYNAMICAL STUDIES … 285 Fig. 4 Seismic reflection profile 7A/ 84, type Slalom Line SL. fold 24, datum plane 300m, scale 1:20,000, ©GEOFOND-CGS Praha. L. Pospíšil et al. 286 Fig. 5 GNSS points in the Moravian area. Part of Culm complex is limited by yellow rectangle. In background of image is Geological map of Czech Republic (Cháb et al., 2007). structures reaching ~1 mm annual velocities or even more (max. 2 mm/year) including the Diendorf-Čebí n tectonic zone (DCTZ (Roštínský et al., 2013), Železné hory – Tišnov tectonic zone ZHT (Švábenský et al., 2014) and wider area of the northern Boskovice Graben (Pospíšil et al., 2017). The studies significantly supplemented geological an d geophysical data on these tectonic zones. For ou r p urposes, the presented GNSS results from the Moravia network (MN - Pospíšil et al., 2017), which were supplemented with data from the East Sudete n N etworks (ESN - Schenk et al., 2002), Sněžník (SN - Švábenský et al. 2012) and marginally Highlands (HN - Schenková et al., 2009) and also with latest unifie d and uniformly reprocessed data of Kaplon et al., (2014). Recent Vertical Movements (RVM) - The study o f the Recent movements of Earth crustal b locks throug h geodetic measurements has been carried out an d ensured on the territory of the Czech Republic through the Research Institute of Geodesy, Topografy an d Cartografy (VÚGTK) since the end of the 1950s. For the purpose of verifying the horizontal movement tendencies, we also used the results o f vertical velocities w0i , obtained from repeate d leveling from 1974-1984, which were equalized fo r the whole territory of the former Czech Republic (Vanko and Vyskočil, 1987). Annual rates have bee n established with respect to the Basic reference poin t ŽELEŠICE (SW from Brno). The leveling networ k was densified throughout the Czech Republic an d results compiled to the map at the original scale o f 1: 200,000, with an isolation interval of 0.1 mm / year. The reduced version of this map to a scale of 1: 1 000 000 (Vyskočil, 1996) was digitized an d modified to a simplified and clearer version but wit h Western Carpathians contact area (Foldyna et al., 1997), later used and remeasured by the Institute of Geodesy at the Brno University of Technolog y (IG BUT); • EAST SUDETEN – b uilt in 1997 by the Institute of Rock Structure and Mechanics, Czec h Academy of Sciences (IRSM CAS to investigate fracture structures in the NE part of the Bohemian Massif (Schenk et al., 2002); • HIGHLANDS – established in 2005 by the Institute of Rock Structure and Mechanics, Czec h Academy of Sciences to study the mountainous areas in the E part of the Bohemian Massi f (Schenková et al., 2009). A few results from the WEST SUDETEN network (N part of the Bohemian Massif; establishe d by the IRSM in 2001; Schenk et al., 2006; Kaplon e t al., 2014) were also applied. Generally, results fro m 10–20 years lasting periods of repeated measurements could be taken into account in case of particula r networks. Since 1994, epoch GNSS measurements in the Czech part of the SNĚŽNÍK network in regula r annual campaigns have been carrying out by the IG BUT (Švábenský et al., 2012). The same institute also participated in the first three campaigns in the MORAVA network (1994–1996), and in 2009–2015 it performed almost complete (except for two points) re-measurement of this network (primary informatio n in (Roštínský et al., 2013; Švábenský et al., 2014, 2011). Moreover, observations at selected points o f the EAST SUDETEN and HIGHLANDS networks were also performed (Pospíšil et al., 2017) indicating recent movements along important active fault zones in the central part of the Eastern Bohemian Massi f (EBM). The main focus of the research was on the UTILIZATION OF ARCHIVE GEOPHYSICAL DATA FOR GEODYNAMICAL STUDIES IN … . 287 Fig. 6 Map of Recent vertical velocities (mm/ a (Vyskočil, 1996), modified by authors). In the are a of interest, vertical motion tendencies of tectonic b locks dominate. Noth of the Bělá fault there are p ositive tendencies, whereas negative tendencies p revail south of it. Tectonic block with Cul m facies on the East area shows relative uplift. C – possition of Bělá fault zone the same resolution, supplied by geological faults (Czech Geological Survey Prague). The underlying layer was used the illuminated radar relief (SRTM DEM data - ©NASA/USGS – illumination 315W/elevation 45 ° (Fig. 6) and DMR 4D (web o f the State Administration of Land Surveying an d Cadastre (CUZK)). This was the way to observe (to show) the relation between morphological structures and active zones with vertical move trends (Fig. 6). RESULTS – GEODYNAMIC DATA ANALYSES The Culm area has one of the highest movemen t tendencies in Moravia. The observed movements b etween the points CBRU, BISK, SADE in the nort h and STRE and HORK points in the south range between -2.1 mmy-1 to -0.4 mmy-1. When comparing with known active fault systems in a given area, it has b een shown that the Bělá tectonic system plays a dominant role here (Buday et al., 1995). The character of the movements, not only according to the results of GNSS measurements (Kaplon et al., 2014), but also according to seismological data (Sýkorová e t al., 2018; Špaček et al., 2015), is interpreted as dextral and is distributed among several segments of the faul t system. The basic knowledge, that can be observed fro m velocity vectors (Kaplon et al., 2014), is that while in the Silesian area all the elements of motion are boun d to the Sudetic Marginal fault and the Bělá fault zone, behind the Šternberk-Horní Benešov fault syste m (Fig. 1) is the main movement of blocks shifted to southern blocks of the continuing the Bělá faul t system (Figs. 3, 4, 7). It is confirmed also b y earthquake foci which are concentrate along and nea r to Haná fault (northern margin of the the Uppe r Moravian Basin (Fig. 7). We have used the reflection seismic profiles from the CGS - GEOFOND database to verify an d especially to identify potential active faults on whic h these recent movements could take place. Because o f the orientation NW-SSE, we have chosen profile 7A/84 (Kolejka et al., 1985 (Fig. 8)), since its direction towards the fault system of Bělá is the mos t complex. The analysis of the other profiles (5/84, 6/84 and 7B/84 (Čížek and Tomek, 1991) shows that the basic structural-tectonic conditions could be fairl y well interpreted, but the detailed tectonic definition o f the individual breaks is very complicated due to the strong shrinkage. Nevertheless, it has been possible to find fundamental changes in the orientation an d inclination of individual reflexes and, in particular, to define the main and fundamental structural horizons i n this area. First of all, it has been shown, in accordance with the previous interpretations (Čížek and Tomek, 1991), that in the section there are clearly differen t orientations of the structures at the top and bottom o f the cut. DISCUSSION AND CONCLUSIONS The presented study evaluating results of the GNSS measurements, additionally confronted wit h regional recent vertical movements and a number o f geomorphological and geophysical indicators, provides a lot of new information about olde r geodynamic and recent kinematic conditions of this area in its most complicated part, just represented b y the Culm area. Application of the complex approac h correlating comparable outputs of more disciplines le d to more reliable description of significant basic o r derived structural features. The previous structural, morphotectonic and geophysical analyses (Badura an d Rauch, 2014; Grygar and Jelínek, 2000; Havíř, 2002, 1999; Jelínek, 2003; Kárník et al., 1984; Labák an d Bouček, 1996; Lenhardt et al., 2007; Pazdírková et al., 2015; Procházková and Kárník, 1978; Schenk et at., 1989; Skácelová and Havíř, 1999; Špaček, et al. 2015, 2008, 2006; Vyskočil, 1996; Zedník et al., 2001) were especially considered at revealing the spatial patterns of linear landforms and their interrelationships wit h regional geophysical fields. Many of these works also included data on historic and primarily recent seismic activity, its focal mechanisms or earthquake patterns, eventually even information about neovolcanite occurrences or CO2 emissions, i.e. phenomen a evidencing true recent geodynamic activity. Whereas the GNSS results are related to surface b lock boundaries, the driving factors are to be searched in deeper parts of the fault structures. Thus, even at the clearly linked cases it is difficult to exactl y estimate the approximate depth level at which the respective movement is currently generated an d determine in more detail its form (commonly steep thrust zone or deep-seated fault). L. Pospíšil et al. 288 some remnants of the Cambrian siliciclastics know n from Southern Moravia and Southern Polan d boreholes? It can be said that archival data continue to p rovide invaluable data for new interpretations, wit h minimal cost. ACKNOWLEDGEMENTS The paper was processed under the BD 12500028, BD 1240001012 and BD 12300008 p rojects of the Brno University of Technology an d was supported by the Ministry of Education, Youth, and Sports of the Czech Republic (grant project SGS SP2018/33). Geological part of the paper has bee n p rocessed on the Geological Division of the Czec h Geological Survey, Department of Regional Geolog y of Moravia. All students of the Geodesy Institute of the Brno University of Technology are primarily thanked fo r their participation in the numerous field GNSS campaigns, which have contributed significantly to the results of this work. REFERENCES Badura, J. and Rauch, M.: 2014, Tectonics of the Uppe r Nysa Kłodzka Graben, the Sudetes. Geol. Sudet., 42, 137–148. Buday, T., Ďurica, D., Opletal, M. and Šebesta, J.: 1995, Importance of the Bělá and Klepáčov faults syste m and its continuation into the Carpathians. Uhlí-RudyGeol. Průzk. 2, 275–282, (in Czech). Cháb, J., Stráník, Z. and Eliáš, M.: 2007, Geological map o f the Czech Republic 1:500,000. Czech Geological Survey, Praha. Čížek, P. and Tomek, Č.: 1991, Large-scale thin-skinne d tectonics in the eastern boundary of the Bohemia n Massif. Tectonics, 10, 2, 273–286. DOI: 10.1029/89TC03241 Foldyna, J., Ratiborský, J., Kabeláč, J., Blažek, R., Grygar, R., Novák, J., Schenk, J., Gavlovský, E., Tyrner, M., Kubečka, E. and Mikulenka, V.: 1997, Final repor t of the GA CR project No. 105/94/1124: Monitoring the supracrustal blocks movements a t the Czech Massif and Alpine-Carpathian Arc b orde r by Global Positioning System (GPS) method. Unpublished research report, VŠB – Technical University, Ostrava and Czech Technical University, Praha, (in Czech). Gnojek, I., Mutlová, A. and Dědáček, K.: 2000, Aeromagnetic map of the Czech Republic based on the grid of data 250m x 250m. Ministry of Environment o f Czech Republic, Archive of GEOFOND-CGS Praha. Grygar, R. and Jelínek, J.: 2000, Alpine and Varisca n Orogeny Belts interaction – an example o f morphostructural analysis (Moravosilesian r egion o f the Bohemian Massif). Geolines, 10, 23–24. Havíř, J.: 1999, The fabric of the Culm conglomerates in the eastern parts of the Nízký Jeseník and Drahany Uplands (eastern margin of the Bohemian Massif, Czech Republic). Geol. Sudetica, 32, 1–11. Havíř, J.: 2002, Recent tectonic activity in the are a northwards of Šternberk (Nízký Jeseník Mts.) - Present knowledge. Acta Montana, Ser. A, No. 20(124), 97–104. Havíř, J.: 2004, Orientations of recent principal stress axes in the Jeseníky region. Acta Geodyn. Geomater., 1, No. 3(135), 49–57. Therefore, the controlling process of suggeste d interpretations should include, besides evaluation o f regional seismic data, also an assessment of available reflection seismic profiles running across the mos t active subareas that facilitate to define a geodynamical character of deep geological structures. The correlation to the gravity, magnetic o r radiometric boundaries appeared to be sufficien t enough to reliable determine the main fault. Moreover, the collaborative application of all three disciplined predicts more important disruptions an d linear fracture systems in the EBM than displayed in the avilable geological maps. When the location o f geomorphological phenomena is additionall y compared with the seismically active tectonic boundaries (Fig. 3), it is also indicated a hig h p ossibility of their generation in deeper parts of the crust. The deduced model of the main active faul t systems (Fig. 8) reflects not only surface structural p lan of the Culm area. A reliability of the propose d geodynamical conception at the deeper structural levels is in case of the two problematic areas supported by a geological assessment of severel reflection seismic profiles (CGS – Geofond): 7A/84, 6/84-83, 5/83-84 (Culmian Complex of the RHH). The former explanation (Buday et al., 1995; Čížek and Tomek, 1991; Hladil et al., 1990) were focused on internal structure of the local Culmian Complex, especially its variable thickness and degree of deformation. The new model (Fig. 8) aimed a t character of the deep basement of the Culmian Complex and more detail inner in the Culmian complex itself: • The seismic profile reflects partly the fold an d thrust structures in the near surface parts. • It starts as a „flower structure“ in the W an d continues most probably as SE-vergent • Bělá fault system is the youngest one, displaces the variscan systems of first and second order an d seems to show an asymmetrical flower structure system • There is an appartent difference in the structural image between the upper segment (above maste r decollement) and lower segment (central an d western part below the master decollement, the „carbonatee complex“) • There are common dome structures within the tectonic slices of the carbonate complex. • Due to the changing orientation (trajectory) of the 7A profile (from NNW-SSE to NNE-SSW) the section does not reflect properly the sense o f tectonic transport • Pure limestones of the Macocha Formation display specific pattern in any part of seismic p rofiles. It is well rocognizable and distinct fro m other lithologies. Nevertheless, a few fundamental questions remain unanswered. Above all, answer the question o f what is in the basement of the Culmian facies? Is i t always metamorphic crystalline basement, or are there UTILIZATION OF ARCHIVE GEOPHYSICAL DATA FOR GEODYNAMICAL STUDIES IN … . 289 Fig. 7 The results of GNSS measurement of movement tendencies in the area of Nízký Jeseník, built by the Culmia n facies (Devonian, Lower Carboniferous), supplemented by interpreted recent faults and earthquake foci. The figure A on the top is supplied by available seismic reflection profiles. The values between individual points are relative differencies. In the figure B - on the bottom are the earthquakes with depths of hypocenters – in the western part of the Cul m area are depths between 10 to 14 km, on the eastern edge - 16 to 24 km. Blue arrows are velocity vectors fro m GNSS measurements (Kaplon et al., 2014), blue letter A - Šternberk-Horní Benešov tectonic zone. A B