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2021 ◽  
pp. 1-11
Author(s):  
Lívio Reily de Oliveira Gonçalves ◽  
Dermeval Aparecido Do Carmo ◽  
Maria José Salas ◽  
Rodrigo Rodrigues Adôrno ◽  
Tõnu Meidla ◽  
...  

Abstract Herein is reported the first occurrence of ostracodes from the Iapó Formation, an uppermost Ordovician unit of the Rio Ivaí Group in the Paraná basin, Brazil. Two ostracode species were identified in the Três Barras Farm section: Harpabollia harparum (Troedsson, 1918) and Satiellina paranaensis Adôrno and Salas in Adôrno et al., 2016 were recovered from dropstone-bearing shale overlying glaciogenic diamictites, a feature typical of Hirnantian (uppermost Ordovician) strata throughout Gondwana. The taxonomy of the Genus Harpabollia, as well as its type species Harpabollia harparum, was reviewed, and emended and new diagnoses were respectively proposed for each taxon. Occurrences of Harpabollia harparum and Satiellina species were common in areas influenced by cold waters. Additionally, the occurrence of Harpabollia harparum, an index species to the uppermost Ordovician of several stratigraphic units in Baltica and southern Gondwana, allowed us to infer a Hirnantian age for the deposits of the Iapó Formation. Other than being associated with Harpabollia harparum in Iapó Formation of the Paraná basin, Satiellina paranaensis is also found in lower levels of the Vila Maria Formation; therefore, these are also considered Hirnantian in age. Above these lower levels of the Vila Maria Formation, a well-dated Rhuddanian (lowermost Llandovery, Silurian) palynomorph assemblage is observed within the formation. These occurrences are evidence of a continuous process of sedimentary deposition during the Ordovician–Silurian transition in the Paraná basin.


2021 ◽  
pp. 1570-1586
Author(s):  
Maryam Al-Hassani ◽  
Salam Al-Dulaimi

The Yamama Formation was studied in three wells (Fh-1, Fh-2, and Fh-3) within Faihaa oil field, south Iraq. Thin sections were studied by using the polarizing microscope examination in order to determine microfossils and biozone. Thirty-five species of benthic foraminifera were recognized, including four index species. In addition,  twelve species of calcareous green algae were recognized, including  two index species. Other fossils that were recognized in Yamama Formation include Gastropoda, Bryozoa, Coral, Rudist, and Pelecypoda. Six biozones were observed, which are Charentia cuvillieri sp. (Range Zone of Berriasian age), Psudochryalidina infracretacea sp. (Range Zone of Berriasian age), Pseudocyclammina Lituus sp. (Range Zone of Valanginian age), Nezzazata Perforate sp.andChoffatella sp.(Assemblage Zoneof Berriasian-Valanginian age), Desycladales Green Algae- Cylindroporella sp. (Range Zone of Early Cretaceous- Berriasian age), and Desycladales Green Algae- Salpingoporella cf. circassa sp. (Range Zone of Valanginian age). According to these biozones, the age of Yamama Formation was distinguished to be the Berriasian-Valanginian.


2021 ◽  
Vol 2 (1) ◽  
pp. 191-195
Author(s):  
Olga T. Obut ◽  
Nikolay V. Sennikov ◽  
Dmitry A. Pecherichenko

New data on the conodont index species from Upper Ordovician of the Teletskoe Lakeside, Gorny Altai, are presented. For the first time for this region representatives of the genera Plectodina and Belodina were found.


Author(s):  
Tamara I. Nemyrovska

Detailed new data on paleontology and stratigraphy were obtained in the process of fulfilling the tasks of the International Carboniferous Subcommission on definition of the scopes of the Moscovian and Kasimovian global stages and the precise position of the boundary between them. The analysis of these data has shown that the position of this boundary in the type  area and in the other regions needs the revision. Recently the investigation of the conodonts from the Moscovian–Kasimovian boundary deposits in the Donets Basin revealed that the boundary between the Moscovian and Kasimovian stages in the official Ukrainian Carboniferous Stratigraphic Scheme does not correspond to this boundary in the type area of these stages in the  Moscow Basin. To correct this situation the lower boundary of the Kasimovian in the Ukrainian Scheme must be downgraded by two conodont zones — Swadelina subexcelsa and Sw. makhlinae. To update this boundary in the type area to fulfill the task of the Carboniferous Subcommission four conodont species were proposed as potential index-species for the definition of the boundary between the Moscovian and Kasimovian global stages. These conodont species are as follows Sw. subexcelsa,  Idiognathodus sagittalis, I. turbatus and I. heckeli. One of these species, which is selected, will be used as a marker of the  studied boundary. None of these species is officially selected as a marker. If Sw. subexcelsa will be selected, the position of  the Moscovian–Kasimovian boundary will remain at the present position. In this case this boundary in the Donets Basin has to be downgraded by two conodont zones. If one of three Idiognathodus will be selected, this boundary in the type area will be   upgraded by one and a half regional substage. In the Donets Basin it will be upgraded by less than a cycle. Keywords: Carboniferous, stratigraphy, conodonts, extinction event, index-­species. 


PalZ ◽  
2021 ◽  
Author(s):  
Jörg Maletz ◽  
Chuanshang Wang ◽  
Wei Kai ◽  
Xiaofeng Wang

AbstractThe Tielugou section, Shennongjia Anticline, Hubei Province (China) includes a relatively complete succession of Hirnantian (latest Ordovician) to basal Telychian (Llandovery, early Silurian) graptolite faunas. The section shows the first record of a fauna of the late Aeronian Stimulograptus halli Biozone from South China, even though the index species was not reported. The Stimulograptus sedgwickii Biozone may not be represented, indicating a possible gap at the base of the Stimulograptus halli Biozone. The interval yields a number of taxa that are elsewhere reported to originate only in the Stimulograptus halli Biozone. The youngest graptolitic levels are included in the Spirograptus guerichi Biozone based on specimens of Parapetalolithus dignus and Parapetalolithus palmeus not known from earlier intervals. Spirograptus guerichi is not represented in the section. The Tielugou section provides the first detailed information on the faunas and thickness of the encountered biostratigraphic units for the Shennongija region.


2021 ◽  
Vol 16 (1) ◽  
pp. 65-85
Author(s):  
Hadinoto Hadinoto ◽  
Eni Suhesti

Birds are one of the ecosystem components that have an important role in supporting the life cycle of organisms. The research objectives were to calculate the diversity of bird species and identify sources of bird feed in mixed gardens. Bird data were analyzed using Species Diversity Index, Species Richness Index, Species Abundance Index, dominance analysis, bird distribution analysis and species encounter level analysis, for vegetation analyzed based on the type and part eaten by the birds. In the mixed garden of Pandau Jaya Village, 27 species of birds were found consisting of 15 families. The types of birds that were frequently present were the Cucak Kutilang (Pycnonotus aurigaster) with 44 individuals and the Perkutut Jawa (Geopelia striata) with 37 individuals. Bird species diversity (H) in mixed gardens was relatively moderate with a value of 2.90, the Evenness Index (E) of 0.88 and the Reachennes Index (R) of 4.40. Vegetation types as a source of food: Mahogany, Jengkol, Jackfruit, Jambu Air, Acacia mangium, Rubber, Matoa, Salam, Angsana, Mango, Breadfruit, Rambutan, Longan, Starfruit, Sengon, Kersen, Lamtoro, Beringin, Ketapang, Mahang, Palm Oil , Coconut, Areca, Palm, Cassava, Sweet Potatoes, Corn, Taro, Eggplant, Chili, Tekokak, Lengkuas, Sugarcane, Long Beans, Banana, Papaya, Flowers,Grasses.


Stratigraphy ◽  
2020 ◽  
pp. 213-278
Author(s):  
Christopher J. Hollis ◽  
Kristina M. Pascher ◽  
Annika Sanfilippo ◽  
Akiko Nishimura ◽  
Shin-ichi Kamikuri ◽  
...  

ABSTRACT: We have integrated southern mid- and high-latitude (Austral) radiolarian biozonations with the well-established low-latitude (Tropical) biozonation using new biostratigraphic and magnetostratigraphic constraints on radiolarian bioevents in the Southwest (SW) Pacific, Southeast (SE) Indian and Northwest (NW) Atlantic Oceans. Our primary study sites include Mead Stream, New Zealand, and DSDP Sites 277 and 207 (SW Pacific; 45-54 degrees South at 50 Ma), ODP Site 752 and IODP Site U1514 (SE Indian; 50 degrees South at 50 Ma), and IODP Site U1403 (NW Atlantic; 30 degrees North at 50 Ma). The Austral and Tropical zonal schemes have been calibrated to GPTS2020. We introduce new zonal codes to rectify current confusion surrounding use of "RP" zones. Austral zones are codified as "RPA" zones and Tropical zones are codified as "RPT". Our study finds that radiolarian datums are generally isochronous within the mid-latitude SW Pacific and SE Indian Oceans from Paleocene to middle Eocene and are also isochronous in the high-latitude Southern Ocean (>60 degrees South paleolatitude) over the late middle Eocene to Oligocene interval of overlap. Older radiolarian assemblages are not known from the Southern Ocean. Early to middle Paleocene radiolarian assemblages in the SE Indian Ocean (zones RPA2-RPA5) differ from coeval SW Pacific assemblages by lacking significant numbers of Cretaceous survivors. The reasons for this difference are uncertain. Although the late Paleocene to Eocene radiolarian assemblages in the SW Pacific and SE Indian Ocean lack many low-latitude index species, the timing of Indian Ocean bioevents agrees better with low-latitude biozonations than the SW Pacific, suggesting a stronger connection with low-latitude watermasses. Assemblages from NW Atlantic IODP Site U1403 include numerous low-latitude index species and can be correlated with zones RPT6-RPT13. Many of the species transitions in biostratigraphically important Eocene lineages, however, occur later than in lower latitudes.


2020 ◽  
Vol 28 (2) ◽  
pp. 135-156 ◽  
Author(s):  
P. Yu. Parkhaev ◽  
Yu. E. Demidenko ◽  
M. A. Kulsha
Keyword(s):  

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