Dian Angelov Vangelov

Sofia University "St. Kliment Ohridski" · Department of Geology and Paleontology

Floods, debris flows, and landslides are hazardous processes that often occurred in mountainous terrains over the world and could be highly destructive. In the last few decades, these events occur more often global, causing disasters as a result of climate changes and poor hazard and risk mitigation measures in the countries. On a regional scale, t...

Quartz, calcite, feldspars, kaolinite, mica (biotite or sericite), and chlorite were determined as predominant minerals. Dolomite, amphibole, and johansenite are presented in smaller quantities. Epidote, hypogene hematite, rarely silver nugget, garnet, rhodonite, and wollastonite are also observed. Pyrite and chalcopyrite, less often sphalerite and...

One of the biggest rivers in the southern part of the Balkan peninsula – the Mesta River is wellknown for frequent flash floods, especially in the upper river course. As a result of severe storms and related heavy rain in mid-July 2019, the Cherna Mesta River flooded, and this resulted in heavy damage to the road infrastructure and water-supply sys...

The tectonic subdivision is a regional method for correlation, very subjective and not always applicable during the field work. Usually, more detailed field investigations do not confirm the regional tectonic schemes, main characteristics of the tectonic units and boundaries. The given example for the Western Srednogorie subzone represents the hand...

Lower Jurassic fossil-bearing red limestone with abundant belemnite rostra is exposed in the form of olistoliths included in the Middle Jurassic Kotel Olistostrome Formation in the surroundings of the town of Kotel in the East Balkan. Following the widely recognized Tethyan “ammonitico rosso” facies, we propose to formalize this distinctive red fos...

The torrential catchments located on the northern slopes of Belasitsa Mountain (SW Bulgaria), in the area of Petrich town were affected by an intense rainfall event in December 2021 that triggered a cascade of hazard processes like floods, landslides, debris flows/floods that caused major damage to the road network, properties, and buildings, showi...

The Ilindenski Kamak is situated along the Ilindenska river valley, northwest of Chelopech village, and is composed of different types of volcanic and volcaniclastic rocks, which are interbedded by sandstones and mudstones, all of Late Cretaceous age. The architecture of the pile of extrusive andesitic rocks is interpreted as a subaqueous cryptodom...

The Ilindenski Kamak is situated along the Ilindenska river valley, northwest of Chelopech village, and is composed of different types of volcanic and volcaniclastic rocks, which are interbedded by sandstones and mudstones, all of Late Cretaceous age. The architecture of the pile of extrusive andesitic rocks is interpreted as a subaqueous cryptodom...

The Ribnishka River watershed, located on the southern slopes of Ograzhden Mountain is known for the repeated torrential events in the last few decades. In this paper, we represent a preliminary assessment of the debris floods and debris flows hazard in the Ribnishka River watershed. For this purpose, the topographic conditions in the watershed are...

At the place where Banderitsa and Demyanitsa rivers and their tributaries ceased to be confined to their narrow valleys one of the most impressive alluvial fans in South Bulgaria is formed – the one of Glazne river. The river valley morphology, as well as the evolution and the position of the Glazne fan, are controlled by the active normal faulting...

The Alpine–Himalayan collision zone involves a number of crustal fragments that originated in the Neoproterozoic to Cambrian Avalonian–Cadomian belt of northern Gondwana. We use the detrital zircon U–Pb geochronology to examine four of these lithotectonic units, now exposed in the Balkans in Bulgaria and Serbia. The obtained age spectra suggest tha...

The investigations of the Upper Cretaceous Panagyurishte and Chelopech volcano-sedimentary strips of the Central Srednogorie tectonic subzone date back to the end of 19 th and became more intensive during the middle of the 20 th century, mainly due to the discovery of important mineral deposits in the area. Our field work during the last 15 years a...

The northwestern narrow tip of the Upper Cretaceous Panagyurishte sedimentary strip is cropping out along the eastern-northeastern margin of the Neogene Sofia graben. In this area the sedimentary strip is split in two parts separated by an uplifted pre-Upper Cretaceous basement block. Both parts show syncline geometries with cores built of Upper Cr...

The Botevgrad basin is one of the numerous Late Pliocene-Quaternary basins developed over the Balkanide orogen. The basin is developed in the West Balkan tectonic zone and on the northern slopes of the Stara Planina Mountain along the Plakalnitsa fault zone, the front of the orogen. The basin was interpreted as half-graben formed on the SW block of...

The Panagyurishte strip of Central Srednogorie Zone, Bulgaria is a part of the Upper Cretaceous magmatic arc belt Apuseni-Banat-Timok-Srednogorie. At the end of the Cretaceous the basin evolution is controlled by transpressive deformation as a result of the oblique southward rejuvenating subduction with retreat and roll-back of the slab of the Neot...

Object of this instrumental research and the archeological characteristic are the samples, which are divided into the following groups: denudated rocks, serving for the base of tectonic clay formation, and used for inorganic temper; clays – tectonic and alluvial; ceramics - pottery fragments and burnt remains of stationary equipment; organic filler...

The Balkan fold-thrust belt, exposed in Bulgaria and north-east Serbia, is part of the north-east vergent segment of the bi-vergent Eastern Mediterranean Alpine orogen. It was formed during two distinct compressional stages; the first one lasted from the Middle Jurassic to the Early Cretaceous and the second from Late Cretaceous to the Paleogene. A...

Along the southern slopes of the Stara Planina Mnt between the villages Bunovo and Anton were described series of brittle N-vergent fault zones (Dimitrov, 1936; Nikolaev, 1947; Kulaksazov, 19571; Milanov et al., 19642; Kuykin et al., 1971; Antonov, Jelev, 2001, 2002). Z. Ivanov (unpublished data) defined “Bebresh- Mirkovo dextral fault zone”. These...

The existence of NW-SE and NNW-SSE trending, regional-scale faults is well-known feature in the area of Tran and Breznik (West Bulgaria). Despite the numerous studies in the area, there is a lack of direct data about the kinematics of the main fault zones. Our investigations allow to define three groups of faults and also demonstrate the dominant d...

The Santonian–Paleocene carbonate sediments exposed in Yankovo section (Eastern Fore-Balkan, NE Bulgaria) are subdivided into six formations: MurnaMiddle Paleocene). Seven microfacies types (MFT 1–7) were distinguished and described in these rocks: very fine-grained bioclastic wackestone/packstone (MFT 1), bioclastic wackestone/float-stone (MFT 2),...

The Santonian–Paleocene carbonate sediments exposed in Yankovo section (Eastern Fore-Balkan, NE Bulgaria) are subdivided into six formations: MurnaMiddle Paleocene). Seven microfacies types (MFT 1–7) were distinguished and described in these rocks: very fine-grained bioclastic wackestone/packstone (MFT 1), bioclastic wackestone/float-stone (MFT 2),...

. High-grade metamorphic rocks from the core of the Variscan orogen on the Bulgarian territory are exposed along the margins of both Zlatitsa and Kamartsi grabens. Here, they are involved into an intense ductile deformation along the regional-scale Stargel-Boluvanya tectonic zone, coinciding with the contact between high-grade basement and the low-...

. High-grade metamorphic rocks from the core of the Variscan orogen on the Bulgarian territory are exposed along the margins of both Zlatitsa and Kamartsi grabens. Here, they are involved into an intense ductile deformation along the regional-scale Stargel-Boluvanya tectonic zone, coinciding with the contact between high-grade basement and the low-...

The Early Neolithic site of Yabalkovo originated from the end of the 7 th , or the very beginning of the 6 th mill. BC. Its life thrives for a few hundred years till the end of the 6 th mill. BC. In the same place, attracted by the favourable natural environment, people settled in the mid. 5 th , 3 rd and 1 st mill. BC. Life here ends in the beginn...

The Balkan Fold-Thrust Belt is a part of the northern branch of the Alpine-Himalayan orogen in the Balkan Peninsula and represents a Tertiary structure developed along the southern margin of the Moesian Platform. The thrust belt displays of two clearly distinct parts: an eastern one dominated exclusively by thin-skinned thrusting and a western part...

Various in age, metamorphic overprint and rock compositions high-grade metamorphic complexes are exposed in the southern parts of the Balkan Peninsula. Until recently all the complexes were presumed to be Precambrian in age. Despite of this groundless assumption, the current geochronological data have shown that the Precambrian age clusters are qui...

The Paleozoic low-grade metamorphic rocks in Shipka Stara Planina Mountains (Fig. 1) comprise a major part of the pre-Mesozoic basement in this area. They have been an object of interest of quite a few studies (Kostov, 1949; Kalvacheva, Prokop, 1988; Yanev et al., 1995). Unsolved problems concerning their tectonic position, stratigraphy and deforma...

The Mesozoic and Cenozoic geodynamic evolution of the fold-and-thrust belt of the Balkanides was related to Early and Late Alpine compressional stages. During the late Alpine collisional stage in Bulgaria the main vergence of the orogen was to the south whereas in its external parts, along Stara Planina Mountain, northward thrusting occurred. The B...

Analysis of structural and sedimentologic data from onshore outcrops, offshore wells, and offshore seismic profiles indicates that the thrust belt geometry in eastern Bulgaria from the Paleocene to the Holocene is characterized by a southeastward plunge toward the western Black Sea Basin. This plunge was caused by (1) a combination of eastward-thin...

The Moesian Platform is well known as a prolific and mature petroleum province on the western margin of the Black Sea. As the promontory of the European Platform, the Moesian Platform is bordered to the north and to the west by the South Carpathians, and to the south by the Balkanides. The vast thickness (>10 km) of Cambrian to Recent sedimentary c...

The pre-Permian basement of Central Stara Planina Mountain consists of two types of rock units – a low-grade dominantly metasedimentary unit (LGMU) and a suite of syn-to postkinematic plutons. Until recently the only known metaigneous rocks within the low-grade metamorphic unit were rarely occurring bodies of metabasic rocks (Cheshitev et al., 1994...

Brittle tectonics analysis and stress tensor reconstructions allow us to better depict the Mesozoic and Cenozoic geodynamical evolution of the Eastern Balkanides which is characterized by a series of overimposed basin-systems. The Late Permian-Triassic corresponds to a wide carbonate platform with local embryonic troughs. During the Jurassic-Early...

After more than 40 years break in the detailed studies of Central Stara Planina an extensive �eld research on the pre-Permian basement in the area was carried out. The newly gathered data require substantial modi�cation of the existing models. Within the basement we are distinguishing two pre-Variscan rock units: low-grade Lower Paleozoic complex a...

After more than 40 years break in the detailed studies of Central Stara Planina an extensive field research on the pre-Permian basement in the area was carried out. The newly gathered data require substantial modification of the existing models. Within the basement we are distinguishing two pre-Variscan rock units: low-grade Lower Paleozoic complex...

After more than 40 years break in the detailed studies of Central Stara Planina an extensive field research on the pre-Permian basement in the area was carried out. The newly gathered data require substantial modification of the existing models. Within the basement we are distinguishing two pre-Variscan rock units: low-grade Lower Paleozoic complex...

In the area of Central Stara Planina Mountain and northernmost parts of Central Sredna Gora the pre-Mesozoic basement of Balkanides is largely exposed. Despite Alpine tectonic overprint the area provides unique chance to deciphering the Variscan history. Of greatest interest is the contact juxtaposing two contrastingly different units (terrains): i...

Along the southern foot of Central Stara Planina Mountain the contact between the high-grade and low-grade metamorphic complexes marks an impor-tant Variscan structure with an orogenic-scale sig-nificance. Interpreted for years as Late Alpine fault, in fact the contact represents a km-scale ductile shear zone. Kinematic data indicate both top-to th...

The Cretaceous-Tertiary (K-T) transition in eastern Bulgaria (Bjala) was analyzed in terms of lithology, mineralogy, stable isotopes, trace elements, and planktic foraminifera. The sequence represents a boreal-Tethyan transitional setting, spans from the last 300 k.y. of the Maastrichtian (zone CF1) through the early Danian (zones P0-Plc), and cont...

The Cretaceous-Tertiary (K-T) transition in eastern Bulgaria (Bjala) was analyzed in terms of lithology, mineralogy, stable isotopes, trace elements, and planktic foraminifera. The sequence represents a boreal-Tethyan transitional setting, spans from the last 300 k.y. of the Maastrichtian (zone CF1) through the early Danian (zones P0-Plc), and cont...