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Based on new U–Pb zircon data, field structural analysis and a detailed petrological study of the plutonic and high-grade metamorphic rocks of the Hammar Domain (Southern Ethiopian Shield) overall geodynamic scenario was inferred, bringing broad implications for the East-African Orogeny. The structural evolution of the Hammar Domain can be summarized into four phases, D1 to D4, resulting in (a) relict compositional banding (S1), (b) flat-lying migmatite foliation (S2) defining the primary contacts of granulites and migmatites, (c) superimposed steeply dipping N–S trending compressional foliation (S3) due to regional ~E–W oriented compression and (d) later ~NW–SE trending left-lateral transpressive fabric (S4). New geochronological data point to long-lasting orogenic convergence forming the East-African Orogeny which resulted in two main geodynamic events: (a) Late Tonian to late Cryogenian episode (ca. 770 to 650 Ma) where large volcanic arc construction as the source of rock photoliths (dated at ca. 770 Ma) was followed by crustal accretion and flat-lying fabrics origin (D2 stage), intense migmatization and HT-MP metamorphism (T: 700–850 °C and P: 0.7–0.9 GPa) at depths of ~25–35 km (dated at ca. 720 and 715 Ma). (b) Late Cryogenian to early Ediacaran episode (ca. 650 to 620 Ma) as the key era of continental collision leading to the Greater Gondwana assembly. An early ~E–W oriented compression (D3 stage) resulted in ~N–S trending fabrics that have been continuously changed to the left-lateral transpression (D4 stage) forming ~NW–SE oriented foliations. The time-scale of D3 and D4 events is inferred by syn-tectonic granitoid intrusions yielded at ca. 648 Ma and ca. 630 Ma respectively. Furthermore, the syn- to post-tectonic leucogranite dike, dated at ca. 630 Ma, marks the upper limit for the ductile or brittle-ductile deformation and regional metamorphic events.

Even though major faults represent important landslide controlling factors, the role the tectonic setting in actively spreading rifts plays in the development of large complex landslides is seldom discussed. The Ameka complex landslide area is located on the eastern scarp of the Gibe Gorge, approximately 45 km to the west of the Main Ethiopian Rift and 175 km to the southwest of Addis Ababa. Investigation of the complex landslide failures required a combination of satellite and airborne data-based geomorphology, geological field survey complemented with structural analysis, radiocarbon geochronology and vertical electric sounding. The obtained observations confirmed the multiphase evolution of the landslide area. We have documented that, apart from climatic and lithological conditions, the main triggering factor of the Ameka complex landslide is the tectonic development of this area. The ~ E–W extension along the ~ NNE–SSW trending Main Ethiopian Rift is associated with the formation of numerous parallel normal faults, such as the Gibe Gorge fault and the almost perpendicular scissor faults. The geometry of the slid blocks of coherent lithology have inherited the original tectonic framework, which suggests the crucial role tectonics play in the fragmentation of the compact rock-masses, and the origin and development of the Ameka complex landslide area. Similarly, the main scarps were also parallel to the principal tectonic features. The local tectonic framework is dominated by faults of the same orientation as the regional structures of the Main Ethiopian Rift. Such parallel tectonic frameworks display clear links between the extension of the Main Ethiopian Rift and the tectonic development of the landslide area. The Ameka complex landslide developed in several episodes over thousands of years. According to the radiocarbon data, the last of the larger displaced blocks (representing only 2% of the total area) most likely slid down in the seventh century AD. The main scarps, namely the high scarps in the western part, are unstable over the long term and toppling and falling-type slope movements can be expected here in the future.

Thirty-two fossiliferous localities of the Olešná Member, a distinct unit of the Klabava Formation, are described. As we are able to find they represent all fossil sites of this unit ever been mentioned in publications. Fossil taxa from relevant papers are summarized and the historical names used for the localities are listed. Updated lists of fauna are compiled for each locality; based on them an overall list for the member is completed.

The Plinian eruption of the Wendo Koshe crater within the Corbetti Caldera occurred around 396 BC. The pumice lapilli deposit, with a thickness exceeding 10 cm, dispersed over an area of over 1000 km2 around the towns of Hawasa and Shashemene. Most of the pumice was deposited by fall-out; however, minor local pyroclastic density currents also occurred. The calculated volume of preserved pumice fall deposit (approximately 1.2 km3), combined with the estimated volume of dispersed fine ash distributed further from the volcano, corresponds to an estimated volume of 0.4 km3 (dense rock equivalent) of erupted magma. The age of the pumice eruption (396 ± 38 BC) was determined by 14C radiometric dating of a paleosoil that developed on previous pyroclastic deposits buried by the pumice. The majority of the post-caldera volcanic products are characterized by a relatively uniform chemical composition (TiO2 = 0.24–0.27 wt.%, Zr = 1300–1600 ppm, ƩREE = 920–1150 ppm) without any significant development in composition. Despite the negligible variations in composition of the magmas that erupted during the last 2500 years within the Corbetti Volcanic System, a significant change in composition was documented prior to the 396 BC Wendo Koshe younger pumice eruption. The caldera stage ignimbrite of Corbetti (TiO2 = 0.34 wt.%, Zr = 500 ppm, ƩREE = 370 ppm) and the early post-caldera obsidians are (TiO2 = 0.34 wt.%, Zr = 800 ppm, ƩREE = 410 ppm) characterized by a commenditic composition, and the character of the rhyolitic magmas shifted towards pantellerites in the post-caldera stage. The compositional contrast is confirmed also by Sr isotope ratios. The Corbetti ignimbrite is characterized by being more radiogenic (87Sr/86Sr = 0.70678) than the post-caldera obsidians (87Sr/86Sr = 0.7046–0.7047). In contrast to the trace-element concentrations, the early Chabi obsidian does not differ from younger obsidians in isotope composition. Similarly to other silicic volcanic systems of the Main Ethiopian Rift, the rhyolitic magmas of the recently active volcanoes within the Corbetti Volcanic System are most likely produced by extreme fractional crystallization of basaltic melts.

Twenty-two fossiliferous localities of the Mílina Formation described herein represent all fossil sites of this unit we have found mentioned in publications. Fossil taxa from relevant papers are summarized and historic names used for the localities are listed. Updated lists of fauna are compiled for each locality; based on these an overall list for the formation is concluded.

Twenty nine fossiliferous localities of the Třenice Formation are described. As we were able to find they represent all fossil sites ever been described from that basal unit of the Prague Basin. Based on critical evaluation of the previously published data fossil taxa from all relevant publications are summa-rized and historic names used for the localities are mentioned. Updated lists of fauna are compiled for each locality as well as for the formation as a whole.