Mihai Emilian Popa

University of Bucharest | Unibuc · Doctoral School of Geology

The Hateg and Rusca Montana basins (South Carpathians, Romania) yield a rich Late Cretaceous (Maastrichtian) compressive megafloral assemblage represented by ferns, conifers, onocotyledons and dicotyledons. This paper focuses on the dicotyledons of these basins, based on recently collected material as well as on historical collections of the Univer...

The Upper Cretaceous (Maastrichtian) formations of the Rusca Montană and Haţeg basins (Romania) yield a compressive fossil flora including the genera Sabalites and Pandanites. The Rusca Montană and Haţeg basins represent very important areas for Cretaceous palms, due to the remarkable density of foliar material and to their palaeogeographic signifi...

The Romanian Early Jurassic (Hettangian–Sinemurian) floras represent a key element of the Eurosinian Province in which the Williamsoniaceae (Bennettitales) are well represented by vegetative remains (leaves, stems, roots) and reproductive structures. Up to the present, Early Jurassic bennettitalean reproductive structures have been found at only tw...

Newly collected Rhaetian plant compressions of the seed fern Ptilozamites nilssonii Nathorst 1878 from Jameson Land, Eastern Greenland, revealed both simple and forked, unipinnate and bipinnate morphologies, indicating a closer relationship between the genera Ptilozamites Nathorst 1878 and Ctenozamites Nathorst 1886 than previously documented. Cuti...

The aim of this study is to evaluate the thermal maturity of Upper Badenian (Middle Miocene) petroleum source rocks of the Getic Depression, Romania, and to characterize the dispersed organic matter using organic petrography associated with Rock-Eval pyrolysis. A total of 33 core samples of Upper Badenian source rocks from the central–southern part...

The end‐Triassic mass extinction is considered one of the “Big Five” extinction events in the Phanerozoic. However, whether the terrestrial ecosystem began to deteriorate or even collapse prior to the Triassic–Jurassic (Tr‐J) transition remains controversial. Compared with the documented data from the western Tethyan region, evidence from the easte...

Global climate and environmental changes were the main causes of the end-Triassic mass extinction. However, direct sedimentological evidence of environmental catastrophes is rare in Triassic – Jurassic interval, especially in the eastern Tethys region. The newly discovered in-situ trunk fossils in paleosol surface and a set of unique branch-support...

Iron Gates Natural Park. Monograph An invitation to Iron Gates Natural Park: Maria Pătroescu, Laurențiu Rozylowicz, Marian C. Jiplea Iron Gates Natural Park. Administrative and legal aspects: Mihai R. Niță, Marian C. Jiplea, Diana A. Onose, Maria Pătroescu The Geography of Iron Gates Natural Park: Steluța Manolache, Iulian M. Niculae, Simona R. Gr...

Ptilozamites Nathorst 1878 is one of the most widespread genera of Mesozoic seed ferns, reaching its highest diversity during the Late Triassic. As a palaeogeographic and biostratigraphic marker restricted to the Late Triassic of the Southern Floristic Province in China, Ptilozamites chinensis Hsü 1950 had once been transferred to the genus Pseudoc...

Well-preserved fruit remains of the genus Sloanea Linné 1753 (Elaeocarpaceae) are reported for the first time in Romania, from the Oligocene Dâlja-Uricani Formation of the Petroșani Basin, South Carpathians. Six fructifications, collected from a sterile dump of the Paroșeni coal mine, are associated on four hand specimens. The fossils are assigned...

Parcul Natural Porţile de Fier: monografie; Invitație în Parcul Natural Porțile de Fier Maria Pătroescu, Laurențiu Rozylowicz, Marian C. Jiplea; Parcul Natural Porțile de Fier. Repere administrative și legislative Mihai R. Niță, Marian C. Jiplea, Diana A. Onose, Maria Pătroescu; Potențialul ecologic al Parcului Natural Porțile de Fier Stelu...

Determining the diversity of past floras helps with interpreting both the history and predicting the future of vegetation change. For global-scale and regional-scale diversity studies especially, secondary data are often used but local-scale studies tend to be based on survey data that require rigorous sampling. The correct sampling strategies depe...

Based on field outcrop data, the effects of cyclic change of astronomical orbit and volcanic activity on organic carbon accumulation during the Late Ordovician – Early Silurian in the Upper Yangtze area were studied using cyclostratigraphic and geochemical methods. δ¹³C and chemical index of alteration (CIA) were used to filter the astronomical orb...

The end-Triassic mass extinction (ETME) is considered to be one of the five most severe extinction events in Earth history and caused the disappearance of ca. 80% of all species. The terrestrial ecosystems were also greatly affected by this extinction, but the severity of the land plant diversity loss is not well understood. Ferns are once a princi...

Anthrophyopsis Nathorst 1878 is a representative Late Triassic foliar genus with uncertain systematic affinities and poorly understood morphology and anatomy. Since its earliest report by Nathorst in 1878, 16 species have been documented worldwide. However, the taxonomic statuses of some taxa remain questionable. Out of 16 reported species, only th...

Palaeobotany and palynology are the main direct sources of evidence for studying vegetation diversity dynamics through geological time. However, plant fossil diversity is affected by various factors other than vegetation diversity, which need to be taken into account in such studies. The use of fossil-taxa will potentially inflate perceived plant d...

Successful evolutionary forms are characterized by their longevity in the fossil record. There are many plant groups that exhibit these traits; here we have selected the ferns as one acknowledged evolutionary model. Ferns are the most successful cryptogamic plants in geologic history and are known from nearly all fossil floras since their first app...

The sequence of Permian volcanic and volcaniclastic rocks (up to 2 km thick) in the Sirinia Basin (Svinița-Svinecea Mare sedimentary zone) of the Upper Danubian Units, South Carpathians, is considered to be the product of subaqueous volcanism passing into a subaerial volcanism and subsequent deposition by debris flow. The investigated volcano-sedim...

The bennettitalean male reproductive structure Weltrichia Braun 1849 emend. Harris 1969 (Family Williamsoniaceae) is discussed from several points of view, including anatomy and morphology, species diversity and validity, phytogeographical and stratigraphical distribution, and reproduction strategy. A very rare fossil, genus Weltrichia includes 25...

Cercidiphyllum crenatum (Unger 1850) R. Brown 1935 (Magnoliophyta, Cercidiphyllaceae Engl.) is reported from the Badenian coal-bearing deposits of the Bozovici Basin, South Carpathians. Although it is a common species in the European Mio-Pliocene deposits, Cercidiphyllum crenatum is a rare species in the Romanian fossil flora, as it was previously...

The end-Triassic mass extinction is one of the five big extinction events in the Phanerozoic, and its impact on marine organisms has been extensively studied. However, whether the terrestrial ecosystem had begun to deteriorate or even collapsed prior to the end-Triassic mass extinction remains controversial and the related studies in Asia are very...

Prezentarea Trilogiei Resursele minerale ale României (coord. E.Constantinescu și N.Anastasiu). Cuprinsul celor trei volume: 2015-Minerale industriale și roci utile; 2017 - Minerale metalice și minereuri; 2019-Resurse energetice.

Pronephrium stiriacum (Unger) Knobloch et Kvaček 1976 (Filicales, Thelypteridaceae Holttum 1971) is reported from the Oligocene Petroșani Basin and from the Miocene Bozovici Basin in Romania. Morphological variations of this species, such as size of the leaves, venation and marginal teeth, in the Oligocene–Miocene time interval in Romania are descr...

The aims of this study include the evaluation and interpretation of Oligocene source rocks from the Central-Western part of the Getic Depression, Romania, and the identification of their maturation and their hydrocarbon potential. 24 argillite samples belonging to the source rocks were studied using organic petrography and geochemistry methods, inc...

This paper is a contribution to the coal geology, coal petrology and end products of coal utilization in Romania. Romanian coals are approached from geological, petrographical and industrial use points of view. This research surveys all Romanian basins yielding terrestrial, coal bearing formations in relation to their stratigraphy, palaeobotany, co...

This paper aims to provide an up-to-date, realistic picture of the Romanian coal sector based on four interconnected perspectives: geological, economical, energy, and strategical. It reviews the latest data, evaluations, and reassessments regarding the potential of current resources and reserves, geological and petrographic aspects, current status...

The Lower Jurassic (Hettangian–Sinemurian) continental deposits of the Mehadia area (Caraş–Severin County) belong to the Presacina Basin, Upper Danubian Units of the South Carpathians, Romania. This un-named succession is exposed along large areas within the Greaţca Quarry where deposits of a complex braided river system can be seen. Nine clastic f...

Evaluation – Integration – Interpretation Oligocene source rock: - types of macerals, random of vitrinite reflectance Ro%, Thermal Alteration Index (TAI), quantity, quality and thermal maturity of organic matter, the interpretation of depositional environment

The Filipesti de Padure lignite is thermally immature with the maximum temperature (Tmax) of Rock-Eval pyrolysis ranging from 339.5 °C to 414 °C. The presence of high TOC values and HI values between 163 and 241mg HC/gTOC, with mixed Type II/III kerogen suggest that the Filipesti de Padure lignite has the potential to generate both oil and gaseous...

The organic matter is identified as being predominantly Type II kerogen (oil - prone) grading it in mixed Type II-III kerogen (oil and gas – prone) as indicated by hydrogen index values (115 – 311 mg HC/gTOC). This is supported by the presence of the significant amounts of oil-prone liptinite macerals.

Coals from Paroseni have a humic composition dominated by vitrinite macerals with significant amounts of liptinite and minor inertinite macerals.

The Bozovici Basin is an intramontaineous basin occurring in the South Carpathians, generated during post-laramian times.

Very large, sparsely distributed, sinuous, gently dipping and occasionally branching tunnels with subordinate swells, as well as possible chambers and scratches, are described from the Hettangian Dealul Budinic Member of the Lower Jurassic continental Steierdorf Formation at Anina in the South Carpathians, Romania, and are interpreted as tetrapod b...

A specimen of Alethopteris zeilleri from Stephanian deposits of Secu, Reşiţa Basin of South Carpathians, Romania, provides additional evidence that these medullosalean pteridosperms bore ovules laterally attached to rachises, probably in the proximal part of the frond. Alethopteris zeilleri foliage is associated with Pachytesta incrassata ovules wi...

Two Early Jurassic localities, the Mecsek Mts in Hungary and Anina in Romania, are similarly significant and both floras are of autochthonous/paraautochthonous origin. In the Early Jurassic the Hungar-ian locality was a delta plain; the Romanian locality was an intramontane depression filled predominantly by a braided river system. The floristic co...

Three main principles lay to the foundations of robust and healthy national scientific research, development, innovation (R&D) and higher education systems: adequate funding, correct assessment of scientific results (individual, institutional, national, peer-review of financing applications, post-grant monitoring) and continuity of R&D and higher e...

Volumul al III-lea Resurse energetice încheie Trilogia Resursele minerale ale României, care cuprinde Minerale industriale şi roci utile – volumul I şi Minerale metalice şi minereuri – volumul al II-lea. Conținutul volumului al III-lea abordează probleme legate de I - hidrocarburi (petrol și gaze naturale), II - cărbuni, III - resurse neconvenționa...

The Jurassic floras of Europe show considerable diversity. To examine the extent of this diver-sity and its possible causes we used multivariate statistical methods (cluster analysis, PCA, NMDS) to com-pare all significant Jurassic floras in Europe. Data were based on 770 taxa from 46 fossiliferous occurrences (25 units) from and the United Kingdom...

The Carboniferous Cucuiova Formation of the Sirinia Basin, Danubian Units, in Almăj Mountains, South Carpathians, yields a highly diverse yet rare compressive flora representing significant heritage values of the “Iron Gates” Natural Park. This flora includes pteridophytes (lycopsids, sphenopsids, filicopsids) and gymnosperms (pteridosperms and con...

Kędzior, A. and Popa, E.M. 2013. Sedimentology of the Early Jurassic terrestrial Steierdorf Formation in Anina, Colonia Cehă Quarry, South Carpathians, Romania. Acta Geologica Polonica, 63 (2), 175-199. Warszawa. The continental, coal bearing Steierdorf Formation, Hettangian - Sinemurian in age, is included in the Mesozoic cover of the Reşiţa Basi...

The Cucuiova Formation is a Pennsylvanian (late Carboniferous) coal-bearing unit in the intramontane Sirinia Basin, which was formed in the Danubian Units of the South Carpathians. The main coal seam in the Cucuiova Formation was worked at Baia Nouă (Nové Doly) and this locality has yielded a typical adpression coal flora. Previous studies have sug...

A new occurrence of the Schizaeaceous fern Klukia exilis (Philips 1829) Raciborski 1890 emend. Harris 1961 is identified in Ahan Sar, a new fossiliferous locality in the Amol area, Mazandaran Province, in Alborz Mountains, Northern Iran. These fossils were collected from a section close to a coal mine in Ahan Sar, included in the Triassic-Jurassic...

Halimeda-bearing deposits of the Middle Atlas Mountains and of the southern rim of the central High Atlas, bordering the Neogene Quarzazate Basin, east of Asseghmon (Morocco), were studied with regard to their lithostratigraphy, biostratigraphy, sequence stratigraphy and carbonate microfacies (Herbig, 1991; Trappe, 1992, Kuss and Herbig, 1993 and D...

Bennettites are an abundant and frequently well-preserved component of many Mesozoic fossil floras, often playing an important ecological role in flood plain vegetation communities. During a recent study focusing on stomatal indices of Triassic–Jurassic fossil plants, it became evident that the leaf fragments of two bennettite genera Anomozamites S...

Early Jurassic (Hettangian–Sinemurian) rare insect ovipositories occurring on Pterophyllum sp. bennettitalean (cycadeoidalean) leaves are described from Pregheda, a former open cast mine for bituminous coals belonging to the Sirinia Basin, Danubian Units of the South Carpathians, Romania. These ovipositories are represented by groups of 2-3 ellipti...

This paper presents and discusses field and laboratory techniques applied to fossil plant compressions, with examples and details related to the the current practice at the Laboratory of Paleobotany within the Research Centre of Coal Geology and Environmental Sciences, University of Bucharest. Field techniques include plant collecting, while labora...

The new species Pecopteris ticleanui sp. nov. is described and figured from Secu, Reșiţa Basin, South Carpathians, Romania, from the Pennsylvanian deposits of the Reșiţa Formation. The studied material included both mature and im-mature frond fragments. The species is rare in both the Reșiţa Basin and generally in the South Carpathians. Pecopteris...

The geological heritage of the South Carpathians is exquisitelly represented by the unique outcrops of the central area of the Reşiţa Basin (Reşiţa-Moldova Nouă sedimentary zone), grouped maily around the Anina (Steierdorf) fossile-Lagerstätte locality, a former coal mining center with highly significant industrial architecture and historical herit...

The dinosaur footprints cf. Parabrontopodus isp. Lockley, Farlow et Meyer, 1994, attributed to sauropods, have been found in Hettangian (earliest Jurassic) alluvial deposits in Anina (Colonia Cehǎ Quarry, Reşita Basin), belonging to the Getic Nappe in the Southern Carpathians, Western Romania. Heteropodous pes-manus sets and one short, narrow-gauge...

The magnitude and pace of terrestrial plant extinction and macroecological change associated with the Triassic/Jurassic (Tr/J) mass extinction boundary have not been quantified using paleoecological data. However, tracking the diversity and ecology of primary producers provides an ideal surrogate with which to explore patterns of ecosystem stabilit...

Palaeobiogeography plays an important role in the evolution of continental plants. This has been demonstrated mainly for modern biota and for past biota on a very large scale only. During the Jurassic–Early Cretaceous Mid-Eastern Europe was an archipelago, thus a particularly suitable area for a more detailed study. We investigated the area's plant...

2 Abstract: New preliminary ichnological results regarding the Lower Jurassic Steierdorf Formation of the Resita Basin (South Carpathians) are discussed in this paper, with emphasis on structures considered as tunnels dug by vertebrates in the basalmost sequences of this formation in Anina, the Czech Colony open cast mine respectively, an exception...

The Upper Carboniferous formations from the Resita and Sirinia Basins (South Carpathians) are described and discussed from palaeobotanical, palynological and sedimentological points of view. Both the Resita and the Cucuiova Formations are continental, detritical, coal bearing sequences with significant macro- and microfloras. Unfortunately, the sta...

Exceptional plant and animal fossils were recorded from Anina, formerly known as Steierdorf, a well known fossiliferous, coal mining locality in the South Carpathians, Resita Basin. The Steierdorf Formation, Hettangian - Middle Toarcian in age, yields a highly diverse and exceptionally preserved land flora, known since the XIX-th Century. The Early...

Exceptional preservation of extinct Pachypteris extra-epidermal cuticle enabled the first detailed statistical measurements of its ultrastructure using transmission electron microscopy. Pachypteris is a leaf genus of the Mesozoic belonging to seed fern foliage of the order Corystospermales. The species studied in this paper is Pachypteris gradinaru...

The Middle Jurassic deposits from Anina area bear rich bivalve assemblages belonging to the Aalenian - Lower Callovian interval. Fourteen bivalve species described and illustrated in this paper were collected from the Ponor and Colonia Ceha quarry, within the Dealul Zanei Marls Formation (Toarcian - Lower Callovian). Facies affinities and paleoecol...