MORFOSTRUKTURNÍ RYSY ČANTORYJSKÉ HORNATINY

The paper deals with morphostructural features of Čantoryjská hornatina Mts. Former nappe structure of Silesian unit was rebuilt by complex of neotectonic movements in the late Tertiary and Quaternary. Morphostructural analysis was orientated to investigations of fault scarps, valley patterns, water stream bed gradients and planation surfaces. We can distinguish several morphostructural subunits with different types and intensity of neotectonics. North and northwestern part of the studied area is in contrast with more uplifted ridge between V. Čantoryje Mt. and V. Stoek Mt. Horst-like structures prevail in the northern part, while vault morphostructures are preserved in southern part of Čantoryjská hornatina Mts

Research and occurence of debris flows accumulations in the Moravskoslezské Beskydy Mts.

Debris flow accumulations are relative frequented forms of relief, which occure in the Moravskoslezské Beskydy Mts. In spite of it have nobody deal with them until recently. There occure these accumulations particularly in the culmination part of mountains. The most affected localities are Smrk Mt., Lysá hora Mt., Javorový vrch Mt. and Slavíč Mt. They exist in two diverse types, that differ by magnitude, transport distance, sedimentology and age. We suppose, that larger accumulations have older age (may be Pleistocene). By smaller accumulations we suppose their recent age. This hypothesis confirm executed dendrochronological research.Debris flow accumulations are relative frequented forms of relief, which occure in the Moravskoslezské Beskydy Mts. In spite of it have nobody deal with them until recently. There occure these accumulations particularly in the culmination part of mountains. The most affected localities are Smrk Mt., Lysá hora Mt., Javorový vrch Mt. and Slavíč Mt. They exist in two diverse types, that differ by magnitude, transport distance, sedimentology and age. We suppose, that larger accumulations have older age (may be Pleistocene). By smaller accumulations we suppose their recent age. This hypothesis confirm executed dendrochronological research

ALUVIÁLNÍ KUŽEL V ÚDOLÍ ČERNÉ OSTRAVICE

Frontal exposure of alluvial fan in the valley of the Černá Ostravice River was studied. 6 samples of alluvial fan material were taken. Sedimentological analysis verified fluvial and debris flows material. Radiocarbon dating was used to establish age of organic material, which was partially eroded by fluvial and debris flows processes. Maximum age of debris flows building fan corresponds with phase of high post-atlantic landslides activity in Poland

MORFOLOGICKÉ A GEOFYZIKÁLNÍ PROJEVY EXTENZE VE VRCHOLOVÉ PARTII SMRKU (1276 M) V MORAVSKOSLEZSKÝCH BESKYDECH

Culmination part of the Moravskoslezské Beskydy Mts in the area of outcrops of rocks of the Silesian unit is marked with vast gravitational disintegration connected with the rise of trenches, counter slope scarps and the following development of landslides, debris flows and rock avalanches. In the culmination part of Smrk Mt (1276 m) crossasymmetrical trench was identified having the direction correspondent with topolineaments identified by means of digital elevation model. Geophysical sounding using the methods of symmetric resistivity sounding, vertical electric sounding and shallow seismic refraction proved the existence of a zone of reduced concentration in the depth of minimum 40 m. The rise of the trench indicates probably lateral spreading of the whole massif of Smrk Mt which induced the presence of tectonic faults, erosion unloading at the development of deep fault gap valleys of Čeladenka and Ostravice Rivers and sinking of rigid sandstone of middle member of Godula formation into plastic layers of slightly rhythmical flysch of lower member of Godula formation

Fossil landslide-dammed lake in the Babínek valley (Vsetínské vrchy Hills): contribution to understanding the Holocene relief development in the flysch Carpathians

Sedimentary sequences deposited in the fossil landslide dammed lake have been studied in the Babínek Brook valley. High variability of sediments in the stratigraphic profiles shows repeated changes in the depositional conditions connected with climatic changes during the Holocene. Radiocarbon dating of organic samples from different layers of the profiles sets the minimum age of the slope deformation (and of the beginning of the impoundment sedimentation) to the Boreal Chronozone (8 730 ± 220 BP) and pin-points the significant changes in the sedimentation dynamics during the Subboreal, Subatlantic and Subrecent Chronozones (5630 ± 150 BP – 610 ± 110 BP).Sedimentary sequences deposited in the fossil landslide dammed lake have been studied in the Babínek Brook valley. High variability of sediments in the stratigraphic profiles shows repeated changes in the depositional conditions connected with climatic changes during the Holocene. Radiocarbon dating of organic samples from different layers of the profiles sets the minimum age of the slope deformation (and of the beginning of the impoundment sedimentation) to the Boreal Chronozone (8 730 ± 220 BP) and pin-points the significant changes in the sedimentation dynamics during the Subboreal, Subatlantic and Subrecent Chronozones (5630 ± 150 BP – 610 ± 110 BP)

Gravitational disintegration of the Čertův Mlýn Mt. (Moravskoslezské Beskydy Mts.)

Silesian Unit represents a geological structure which is highly affected by deep-seated gravitational slope deformations on many places. One of famous examples of spreading of a mountain ridge is located on the elevation of Čertův Mlýn Mt. in the highest part of the Moravskoslezské Beskydy Mts. Besides typical displays of double ridges, crevice-type caves, counter-scarp slopes and shallow landslides there are huge tectono-gravitational block deformations. Some manifestations of gravitational spreading were dated to the period of quite young Holocene (Subboreal-Subatlantic). Geophysical measurement revealed that gravitational deformations prograde to the depth even in areas without observable topographic manifestations.Silesian Unit represents a geological structure which is highly affected by deep-seated gravitational slope deformations on many places. One of famous examples of spreading of a mountain ridge is located on the elevation of Čertův Mlýn Mt. in the highest part of the Moravskoslezské Beskydy Mts. Besides typical displays of double ridges, crevice-type caves, counter-scarp slopes and shallow landslides there are huge tectono-gravitational block deformations. Some manifestations of gravitational spreading were dated to the period of quite young Holocene (Subboreal-Subatlantic). Geophysical measurement revealed that gravitational deformations prograde to the depth even in areas without observable topographic manifestations

PLEISTOCENNÍ PERIGLACIÁLNÍ MODELACE OKOLÍ VYSOKÉ HOLE (PRADĚDSKÁ HORNATINA)

Significant denudation and areal reduction of pre-Quaternary ridges and planation surfaces took place during the Pleistocene period in the area of Hrubý Jeseník Mts. Cryoplanation was structural controlled and the cryoplanation itself conditioned evolution of cryoplanation surfaces, cryoplantion terraces, tors, frost riven cliffs and scarps at the top area of the Hrubý Jeseník Mts.The watershead parts situated in homogenous and less resistant rocks were under influences of denudation, intensive frost weathering and eolian processes. The summit surface of the Vysoká hole Mt. (1464 m a.. s. l.) area (the top part of Pradědská hornatina Mts) has been analysed by surface-geophysical method of shallow seismic refraction. Georelief modifying by frost weathering has beed verified by geophysical measurements in the minimum depth of 13 m. On the southwestern cryoplanation terrace of Petrovy kameny (1438 m a. s. l.) the underlying rock was affected by frost weathering in the minimum depth of 10 m