Papers by Mansoureh Ghobadipour
WOGOGOB-2004 8th Meeting on the Working Group on the Ordovician Geology of Baltoscandia May 13–18, 2004, Tallinn and Tartu, Estonia Organising Comittee, 2004
In the abandoned Aluvere quarry near Rakvere, south of the Tallinn–Narva road, the limestone succ... more In the abandoned Aluvere quarry near Rakvere, south of the Tallinn–Narva road, the limestone succession of the Kahula Formation, Haljala Stage (Caradoc) is exposed. In the southern wall of the quarry 6 m of limestone can be studied, characterising the Aluvere and Pagari members of the Kahula Formation (Jõhvi Substage of the Haljala Stage; Fig. 1). The limestone can be classified as wackestone to packstone with a varying content (10–25%) of siliciclastic mud. This siliciclastics content varies rhythmically, as 10–20 cm thick cycles, ...
Estonian Journal of Earth Sciences
The Late Devonian (late Famennian) phacopid trilobites represented by Omegops tilabadensis sp. no... more The Late Devonian (late Famennian) phacopid trilobites represented by Omegops tilabadensis sp. nov. are described and illustrated from the Khoshyeilaq Formation, eastern Alborz Mountains, North Iran. The species formed a monotaxic trilobite association inhabiting a shallow shelf together with diverse brachiopod communities dominated by the athyridides and spiriferides. Constant differences in pygidial morphology between the geographically separated Omegops species from the Middle East, Northwest China (Junggar) and West Europe plus the North African sector of Gondwana may suggest the existence of two geographically isolated Omegops lineages which diverged in pre-Strunian time. The occurrence of conodonts not older than the Bispathodus costatus Zone and the brachiopod Rhipidomella michelini gives a sufficient proof of the Strunian to early Tournaisian age of the uppermost part of the Khoshyeilaq Formation.
Lethaia
Exceptionally preserved, silicified and articulated complete shells of the rhynchonelliform kutor... more Exceptionally preserved, silicified and articulated complete shells of the rhynchonelliform kutorginate brachiopod Nisusia sulcata are redescribed from the middle Cambrian (Series 3) Marjum Limesto ...
Review of current progress in Mid to Late Ordovician astrochronological studies exposes some impo... more Review of current progress in Mid to Late Ordovician astrochronological studies exposes some important issues related to cyclostratigraphical studies, including the completeness and correlation of successions, and the connection between inferred astronomical cycles and geological events recorded in the sedimentary record. While bulk, low-field, mass specific magnetic susceptibility methods are widely applied in studies of high resolution cyclostratigraphy, they require close support from sequence stratigraphy and biostratigraphy, and should be linked back to outcrop patterns. Otherwise they risk distortion in the calibration against geological time, through lack of anchoring to well-defined biostratigraphical horizons and unrecognised condensed intervals and larger hiatuses. A significant limitation currently is that few high-resolution radio-isotope ages are linked to well-defined biostratigraphical boundaries. Nevertheless, fourth order sedimentary sequences linked to 405 ky orbit...
The National fossil Day (NFD) was first established in the United States (October 13, 2010) to en... more The National fossil Day (NFD) was first established in the United States (October 13, 2010) to endorse the value of fossils in science and education. Since that time, different partners including research institutions, universities, museums and other groups come together to share their activities and celebrate the NFD in the United States. Recently, the International Palaeontological Association (IPA), as the coordinator of international cooperation and activities in palaeontology, promotes the NFD and has invited museums, universities and other scientific institutions of the world to celebrate this day. The Iranian Paleontological Society (IPS), as a member of IPA, acknowledged this event by celebrating and promoting the importance of fossils and actions on their protection for people on October, 25, 2017.
Gondwana Research
Limestones of the Xihaoping Member of the Dengying Formation in the Xiaoyangba section, South Chi... more Limestones of the Xihaoping Member of the Dengying Formation in the Xiaoyangba section, South China, yield the oldest known Cambrian brachiopod-trilobite association. In this member, the trilobite Parabadiella cf. huoi co-occurs with the new brachiopod species Eoobolus incipiens sp. nov. The association provides potential for correlation of lower Cambrian successions and gives novel insights into the origin, palaeobiogeographic distribution and early evolution of linguliform brachiopods. Parabadiella occurs in shallow marine clastic and carbonate rocks in South China, demonstrating a broad distribution for this taxon. The new discovery indicates an early Chiungchussuan age (Parabadiella trilobite Zone, Cambrian Age 3) for the longstanding problematic Xihaoping Member. Furthermore, this earliest Parabadiella-Eoobolus association helps to establish close links with the oldest known trilobite-brachiopod assemblage from the upper Micrina etheridgei Zone (Parabadiella huoi trilobite Zone) in Australia. Eoobolus incipiens represents one of the earliest known linguliform brachiopods, with a distinctive mixture of characters shared with both problematic tommotiids, as well as paterinide, lingulide and acrotretide brachiopods, indicating that these features may be plesiomorphic for the Linguliformea. An ageconstrained dispersal mode for early lingulate brachiopods is proposed, indicating that the Subphylum Linguliformea may have originated in East Gondwana and South China during Cambrian Age 3, and only subsequently dispersed to other major Cambrian palaeocontinents (e.g. Siberia, Laurentia, Antarctica, Baltica, Avalonia, West Gondwana, North China) during the late stage of the Cambrian evolutionary radiation of animals.
Bulletin of Geosciences
In the Mid to Late Ordovician the area of the Ougarta Range in northwest Africa occupied a positi... more In the Mid to Late Ordovician the area of the Ougarta Range in northwest Africa occupied a position in relative proximity to the South Pole. Eight successive low diversity brachiopod faunas, including the lingulide association dominated by unnamed species of Lingulobolus, the Darriwilian ?Sivorthis fraterna and Tissintia convergens, the Sandbian to early Katian Drabovinella regia and Tafilaltia destombesi-Rostricellula ambigena associations, the mid Katian Drabovinella maxima and Svobodaina cf. havliceki associations and the late Hirnantian Plectothyrella crassicostis chauveli Association are recognised. The brachiopod based correlation with the Middle to Upper Ordovician succession of the Anti-Atlas in Morocco, suggests the presence of some gaps in the Ougarta section. The occurrence of Svobodaina cf. havliceki in the Bou MʼHaoud Formation Upper Member suggests its correlation with the upper part of the Lower Ktoua Formation of the Anti-Atlas. Among the other brachiopod taxa Drabovinella regia, Orbiculothyris cf. costellata, Tafilaltia destombesi, Rostricellula ambigena, together with the genera Fehamya, Mezotreta and Leptaena were previously unknown from Algerian Sahara.
Estonian Journal of Earth Sciences, 2018
The Late Devonian (late Famennian) phacopid trilobites represented by Omegops tilabadensis sp. no... more The Late Devonian (late Famennian) phacopid trilobites represented by Omegops tilabadensis sp. nov. are described and illustrated from the Khoshyeilaq Formation, eastern Alborz Mountains, North Iran. The species formed a monotaxic trilobite association inhabiting a shallow shelf together with diverse brachiopod communities dominated by the athyridides and spiriferides. Constant differences in pygidial morphology between the geographically separated Omegops species from the Middle East, Northwest China (Junggar) and West Europe plus the North African sector of Gondwana may suggest the existence of two geographically isolated Omegops lineages which diverged in pre-Strunian time. The occurrence of conodonts not older than the Bispathodus costatus Zone and the brachiopod Rhipidomella michelini gives a sufficient proof of the Strunian to early Tournaisian age of the uppermost part of the Khoshyeilaq Formation.
Papers in Palaeontology
A moderately diverse assemblage of micromorphic linguliform brachiopods, including Tapuritreta gr... more A moderately diverse assemblage of micromorphic linguliform brachiopods, including Tapuritreta gribovensis sp. nov., Wahwahlingula? pankovensis sp. nov., Acrothele sp., Anabolotreta? sp., Orbithele? sp. and Stilpnotreta sp., is for the first time described from the Cambrian Karpinsk Formation (Miaolingian, Guzhangian) of the South Island of Novaya Zemlya. The morphology of the metamorphic shell in Acrothele and Wahwahlingula? suggest that both taxa had a single pair of larval setal sacs, similar to the recent discinids, but their metamorphosis was completed only at the end of the pelagic stage and shows that they did have direct development, which is characteristic of all recent lingulides. The biogeographical signature of the new Cambrian brachiopod fauna from Novaya Zemlya is discussed, and the new fauna gives new information on the poorly known Cambrian margins of the Baltica palaeocontinent.
Papers in Palaeontology
A comprehensive review and phylogenetic analysis of genera and species presently assigned to the ... more A comprehensive review and phylogenetic analysis of genera and species presently assigned to the rhynchonelliform superfamily Nisusioidea and family Nisusiidae suggests that this short-lived but important group of brachiopods first appeared in peri-Gondwana during the second half of the Cambrian Series 2, before going extinct by the end of Drumian times. Nisusiides achieved their maximum morphological disparity and geographical distribution during the Wuliuan Age, and Laurentia was probably the major centre of their dispersal. A new phylogenetic analysis suggests an early separation of the lineages of spinose and non-spinose nisusiids. The non-spinose nisusiids probably evolved in Laurentia by the end of Cambrian Series 4. The new nisusiid genus Bellistrophia is described. The new species Nisusia multicostata represents the first documented rhynchonelliform (kutorginide) brachiopod from the Miaolingian (Drumian) of the Alborz Mountains, Iran.
Alcheringa: An Australasian Journal of Palaeontology
Ghobadi Pour, M., 21 June 2019. Ordovician trilobites from Deh-Molla, eastern Alborz, Iran. Alche... more Ghobadi Pour, M., 21 June 2019. Ordovician trilobites from Deh-Molla, eastern Alborz, Iran. Alcheringa 43, 381–405. ISSN 0311-5518 Seventeen species from 14 genera of Tremadocian and Darriwilian trilobites, plus two taxa recognizable only down to family level, have been documented from the Lower to Middle Ordovician succession of the Deh-Molla area, southeast of Shahrud in northern Iran. Two species, Asaphellus intermedius and Conophrys multituberculatus, are new to science. Unlike previously documented Iranian faunas, the early Tremadocian trilobite assemblage is characterized by proliferation of the olenid Chungkingaspis sinensis, which is also known as the eponymous taxon of the basal Ordovician trilobite biozone in South China. This is the first record of the occurrence of the olenid biofacies in the Ordovician of Iran. Overall, both the Tremadocian and Darriwilian trilobite assemblages show distinct similarity to the contemporaneous faunas of South China down to species level. Trilobite-based correlation with the Ordovician succession of South China confirms the existence of a hiatus at the base of the Ordovician succession in the eastern Alborz and a significant gap, with the upper Tremadocian, Floian and Dapingian parts of the succession completely missing in Deh-Molla. Mansoureh Ghobadi Pour [[email protected] and [email protected]], Department of Geology, Faculty of Sciences, Golestan University, Gorgan 49138-15739, Iran. *Also affiliated with Department of Natural Sciences, Natural Museum of Wales, Cardiff, Cathays Park, Cardiff CF10 3NP, UK.
The Tremadocian (Early Ordovician) is currently considered a time span of greenhouse conditions w... more The Tremadocian (Early Ordovician) is currently considered a time span of greenhouse conditions with tropical water surface temperature estimates, interpolated from oxygen isotopes, approaching 40°C. In the high-latitude Baltoscandian Basin, these data are in contrast with the discovery of glendonite, a pseudomorph of ikaite (CaCO3·6H2O) and valuable indicator of near-freezing bottom-water conditions. The massive precipitation of this climatically sensitive mineral is associated with transgressive conditions and high organic productivity. Surprisingly, the precipitation of glendonite is contemporaneous with the record of conodonts displaying low δ values, which would suggest high temperatures (>40°C) in the water column. Therefore, the early Tremadocian sediments of Baltoscandia contain both 'greenhouse' pelagic signals and near-freezing substrate indicators. This apparent paradox suggests both the influence of isotopically depleted freshwater yielded by fluvial systems, ...
Acta Geologica Polonica
The Silurian biostratigraphy, lithostratigraphy, and facies of Central Iran including the Kashmar... more The Silurian biostratigraphy, lithostratigraphy, and facies of Central Iran including the Kashmar (Boghu Mountains), Tabas (Derenjal Mountains, Ozbak-Kuh), Anarak (Pol-e Khavand) and Kerman regions is reviewed and updated. The current state of knowledge of the Silurian in the Zagros Basin, Alborz, Kopet-Dagh and Talysh regions, as well as in a few areas scattered across the Sabzevar Zone, and the Sanandaj-Sirjan terranes is also reviewed. Silurian volcanism in various parts of Iran is briefly discussed. The end of the Ordovician coincided with a widespread regression across Iran synchronous with the Hirnantian glaciation, and only in the Zagros Basin is there a continuous Ordovician-Silurian transition represented by graptolitic black shales of the Sarchahan Formation. In the Central-East Iranian Platform marine sedimentation re-commenced in the early to mid Aeronian. By the Sheinwoodian, carbonate platform depositional environments were established along its north-eastern margin. I...
Papers in Palaeontology, 2017
Ordovician (Darriwilian to Sandbian) micromorphic linguliform lingulate brachiopods are described... more Ordovician (Darriwilian to Sandbian) micromorphic linguliform lingulate brachiopods are described from the Guniutan Formation at the Fenxiang section in Hubei province, and the Maocaopu and Cili sections in Hunan province of south-central China, situated on the Yangtze Platform. A total of 7560 specimens from 155 limestone samples (within the interval of Lenodus variabilis-Pygodus anserinus biozones) are assigned to 22 species, representing a low taxonomic diversity and low abundance fauna. The fauna is dominated by the Acrotretoidea, mainly species of the Torynelasmatidae, with Torynelasma the most abundant (more than 40% of total number of specimens), along with the Eoconulidae and Eoconulus (18% of total) representing the second most common forms. Species of the Ephippelasmatidae are also common (16% of total) diverse, and include representatives of Myotreta and Numericoma, as well as Ephippelasma, whereas species of the Scaphelasmatidae are somewhat less common (13% of total). All three investigated sections represent outer shelf environments, but the Maocaopu section is situated in a relatively deeper position, in proximity of the southeastern outer margin of the Upper Yangtze Platform, close to its boundary with the Jiangnan Slope. A quantitative analysis of the relative abundance data was carried out in order to investigate the biofacies distribution of the micromorphic brachiopod communities across the Yangtze Platform, something that has not been attempted before with Palaeozoic linguliforms. Six lingulate microbrachiopod communities could be recognized in the sections. The major biofacies shift, which occurred in the Cili section in the upper part of the Microzarkodina ozarkodella Zone, at the time of the onset and initial rise of the Mid Darriwilian Carbon Isotope Excursion (MDICE) suggests that these biofacies may have been depth controlled.
Bulletin de la Société Géologique de France, 2005
Two echinoderm assemblages are described in the Middle Ordovician of Iran (Darriwilian). The Sime... more Two echinoderm assemblages are described in the Middle Ordovician of Iran (Darriwilian). The Simeh Kuh section (Damghan area, eastern Alborz range) has yielded a rich and diverse blastozoan fauna consisting of fistuliporite (Echinosphaerites, Heliocrinites) and dichoporite rhombiferans (cheirocrinids indet., hemicosmitids indet.), as well as aristocystitid (Sinocystis) and sphaeronitid diploporites (Glyptosphaerites, Tholocystis). Heliocrinites, cheirocrinids, hemicosmitids, Glyptosphaerites, and Tholocystis are reported for the first time in the Ordovician of Iran. A less diverse assemblage was collected in the Shirgesht section (Tabas area, Derenjal Mountains), and represents the first report of Ordovician echinoderms in east-central Iran. The Shirgesht fauna includes fistuliporite rhombiferans (Heliocrinites), aristocystitid and sphaeronitid diploporites. The new Iranian material documents some of the earliest known assemblages of diploporites and rhombiferans, and thus, brings i...
Stratigraphy
A continuous succession comprising upper Cambrian (Furongian) to Lower Ordovician (Tremadocian) c... more A continuous succession comprising upper Cambrian (Furongian) to Lower Ordovician (Tremadocian) conodont biozones is reported for the first time from the Kopet-Dagh Region of northeastern Iran. Seven biostratigraphical units are recognized, including the Proconodontus tenuiserratus and Proconodontus posterocostatus zones; these two lowermost biostratigraphical units are defined by euconodont species which have not been previously reported from Iran and temperate latitude peri-Gondwana. The conodont diversity and abundance decreased significantly above the Eoconodontus notchpeakensis Zone; the conodont faunas of the succeeding Cordylodus proavus, Cordylodus lindstromi (sensu lato) and Cordylodus angulatus zones are characterised by oligotaxic to monotaxic associations dominated by species of Cordylodus. In the absence of diagnostic conodont species, the position of the lower boundary of the Ordovician System in the Kalat Valley Section can be placed somewhat below the first occurrenc...
Stratigraphy
The Pole Khavand area southeast of the town of Anarak preserves important clues for understanding... more The Pole Khavand area southeast of the town of Anarak preserves important clues for understanding geological evolution of Central Iran during the Palaeozoic. New observations confirm the non-conformable relationship between Doshakh metamorphites and overlying unmetamorphosed Lower Palaeozoic sediments, suggesting accretion of the volcanic arc in front of the Yazd block sometime in the late Cambrian to early Ordovician. The newly introduced volcano-sedimentary Polekhavand Formation preserves evidence of a ?Late Cambrian to Early Ordovician post-collisional bimodal volcanism and related extensional regime in the Pole Khavand area during that time. The Middle to Upper Ordovician interval of the studied succession is assigned to the newly introduced Chahgonbad Formation. The Darriwilian age of the base of this lithostratigraphical unit is demonstrated by the brachiopods Tritoechia and Yangtzeella which co-occur with a diverse a cephalopod assemblage. The low diversity fauna including br...
To assess biogeographic affinity of the Late Cambrian (Furongian) and the Early Ordovician (Late ... more To assess biogeographic affinity of the Late Cambrian (Furongian) and the Early Ordovician (Late Tremadocian) faunas of Eastern Alborz, a multivariate cluster analysis using the pair-group Raup-Crick similarity index has been applied. The Late Cambrian fauna of Alborz shows clear Gondwanan signatures with the closest affinities to the contemporaneous faunas of temperate latitude peri-Gondwana (Central Iran, Oaxaquia terrane in southern Mexico) and in slightly lesser degree with low latitude faunas of the Karatau Naryn microplate (southern Kazakhstan) and the Australasian segment of Gondwana. Thus, outcome of the analysis suggests that by the second half of the Furongian, which was the time of proliferation of the early euconodonts, the Alborz terrane approached and probably entered temperate latitudes. In the Late Tremadocian links of Alborz conodont faunas with temperate latitudes faunas of Gondwana and Baltica became more evident. Assessment of the Cambrian (Furongian) and Early Ordovician (Late Tremadocian) conodont faunas of the Alborz are in favor of its isolated position at some distance the western Gondwanan coast.
Estonian Journal of Earth Sciences, 2015
Restudy of the Cambrian-Ordovician boundary beds, traditionally assigned to the Mila Formation Me... more Restudy of the Cambrian-Ordovician boundary beds, traditionally assigned to the Mila Formation Member 5 in Mila-Kuh, northern Iran, for the first time provides convincing evidence of the Early Ordovician (Tremadocian) age of the uppermost part of the Mila Formation. Two succeeding trilobite assemblages typifying the Asaphellus inflatus-Dactylocephalus and Psilocephalina lubrica associations have been recognized in the uppermost part of the unit. The Tremadocian trilobite fauna of Mila-Kuh shows close similarity to contemporaneous trilobite faunas of South China down to the species level, while affinity to the Tremadocian fauna of Central Iran is low. The trilobite species Dactylocephalus levificatus and brachiopod species Tritoechia tenuis from the Tremadocian of Mila-Kuh are new to science.
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Papers by Mansoureh Ghobadipour