Sequence stratigraphic and sedimentologic significance of the trace fossil Rhizocorallium in the Upper Triassic Nayband Formation, Tabas Block, Central Iran

2018 ◽  
Vol 491 ◽  
pp. 196-217 ◽  
Author(s):  
Aram Bayet-Goll ◽  
Carlos Neto de Carvalho ◽  
Mehdi Daraei ◽  
Paolo Monaco ◽  
Mahmoud Sharafi
Keyword(s):  
Upper Triassic ◽  
Trace Fossil ◽  
Central Iran ◽  
Sequence Stratigraphic ◽  
Nayband Formation

Stenolaemate bryozoans from the upper triassic (Norian-Rhaetian) Nayband Formation, Central Iran

Facies ◽  
2003 ◽  
Vol 48 (1) ◽  
pp. 135-150 ◽  
Author(s):  
Priska Schäfer ◽  
Baba Senowbari-Daryan ◽  
Ali Hamedani
Keyword(s):  
Upper Triassic ◽  
Central Iran ◽  
Nayband Formation

First hexactinellid sponge reported from the Upper Triassic Nayband formation of central Iran

2007 ◽  
Vol 81 (6) ◽  
pp. 1538-1542 ◽  
Author(s):  
J. Keith Rigby ◽  
B. Senowbari-Daryan
Keyword(s):  
Scleractinian Corals ◽  
Upper Triassic ◽  
Central Iran ◽  
Hexactinellid Sponge ◽  
Nayband Formation ◽  
Hexactinellid Sponges

Sponges, along with scleractinian corals, are among the main reef-building organisms in Triassic reefs. Hypercalcified groups, including the chambered sphinctozoans, and the unchambered inozoans, chaetetids, and spongiomorphids, represent the most abundant Triassic reef-building sponges. Earlier workers have described elements of the latter group as “hydrozoans.” Hexactinellid sponges, abundant in some Permian reefs (e.g., in Texas, Finks, 1960), are rarely known from similar Triassic deposits, in general (Tichy, 1975), and particularly from Upper Triassic stratigraphic units. Hexactinellid sponges have been sporadically reported from well-investigated Upper Triassic reefs in the western Tethyan region (e.g., Keupp et al., 1989). However, a variety of hexactinellid sponges have been reported from Upper Triassic deposits and reefal limestones of the northern and central Tethyan realm (Boiko, 1990; Wu, 1989; Wu and Xiao, 1989; Rigby et al., 1998).

scholarly journals Wildfire Events at the Triassic-Jurassic Boundary of the Tabas Basin, Central Iran

2020 ◽  
Author(s):  
Majid M Alipour ◽  
Bahram Alizadeh ◽  
AmirAbbas Jahangard ◽  
AhmadReza GandomiSani
Keyword(s):  
Major Change ◽  
Lower Jurassic ◽  
Upper Triassic ◽  
Central Iran ◽  
Sharp Boundary ◽  
Depositional Settings ◽  
Run Off ◽  
Clastic Sediments ◽  
Nayband Formation ◽  
Microscopic Charcoal

Abstract This paper presents organic geochemical evidence pointing to the occurrence of wildfire events at the Triassic-Jurassic boundary in Central Iran. The studied outcrop section (the Kamarmacheh Kuh section) is comprised of the Upper Triassic Nayband Formation which passes conformably into the Lower Jurassic Ab-e-Haji Formation with no sharp boundary. Organic petrographical studies reveal a higher concentration of semi-fusinite macerals and microscopic charcoal at the boundary between studied formations. This observation can be an evidence for widespread wildfire events at the Triassic-Jurassic boundary of the studied area. Following these fires, vast areas of land were exposed for erosion and large volumes of clastic sediments were provided due to increased run-off. This agrees well with previous sedimentological and stratigraphical studies suggesting a major change in the depositional conditions from marine to non-marine at the Triassic-Jurassic boundary of the Tabas Basin. These findings can have important implications about paleo-depositional settings of the studied formations and the nature of the associated organic matter.

Depositional history and sequence stratigraphy of central Tethyan from the Upper Triassic Nayband Formation, Central Iran

2020 ◽  
Vol 35 (1) ◽  
Author(s):  
Asghar Etesampour ◽  
Asadollah Mahboubi ◽  
Reza Moussavi-Harami ◽  
Nasser Arzani ◽  
Hoseinali Bagi
Keyword(s):  
Sequence Stratigraphy ◽  
Upper Triassic ◽  
Central Iran ◽  
Depositional History ◽  
Nayband Formation

The palynology of the Nayband Formation (Upper Triassic) of the Tabas Block, Central Iran

2020 ◽  
Vol 282 ◽  
pp. 104308
Author(s):  
Hossein Sabbaghiyan ◽  
Mohammadreza Aria-Nasab ◽  
Ebrahim Ghasemi-Nejad
Keyword(s):  
Upper Triassic ◽  
Central Iran ◽  
Nayband Formation

Surface to subsurface correlation of the Middle-Upper Triassic Shublik Formation within a revised sequence stratigraphic framework

2020 ◽  
Vol 8 (2) ◽  
pp. SJ1-SJ16
Author(s):  
William A. Rouse ◽  
Katherine J. Whidden ◽  
Julie A. Dumoulin ◽  
David W. Houseknecht
Keyword(s):  
Large Scale ◽  
Gamma Ray ◽  
Upper Triassic ◽  
North Slope ◽  
Depositional Sequences ◽  
Sequence Stratigraphic ◽  
The North ◽  
Depositional Patterns ◽  
Resource Exploration ◽  
Unconventional Resource

Recent work on cores and outcrops of the Middle-Upper Triassic Shublik Formation has facilitated surface to subsurface correlation of depositional sequences across the Alaska North Slope. Five transgressive-regressive depositional sequences have been defined within three large-scale stratigraphic units. Outcrop spectral gamma-ray (GR) profiles were used to correlate observed stacking patterns with nearby exploration wells, and GR logs from 161 exploration wells were used to correlate the three large-scale stratigraphic units across the North Slope and nearby offshore. Interpretations of depositional facies and sequence stratigraphy in cores from 26 wells were used to corroborate regional correlations. Isochore maps constructed for each of the three stratigraphic units illustrate the influence of accommodation on depositional patterns and suggest reactivation of several older tectonic elements during Shublik deposition. An isochore map of the richest, oil-prone interval of the Shublik Formation reveals a thick pod south of Harrison Bay, the eastern part of which lies beneath a recent giant Shublik-sourced oil discovery in the Cretaceous Nanushuk Formation. In addition, when integrated with thermal maturity, this isochore map may provide leads for areas that are optimal for unconventional resource exploration.

The Fish River Subgroup in Namibia: stratigraphy, depositional environments and the Proterozoic–Cambrian boundary problem revisited

2005 ◽  
Vol 142 (5) ◽  
pp. 465-498 ◽  
Author(s):  
G. GEYER
Keyword(s):  
Trace Fossils ◽  
Global Scale ◽  
Depositional Environments ◽  
Trace Fossil ◽  
Braided River ◽  
Shallow Marine ◽  
Sequence Stratigraphic ◽  
Marine Habitats ◽  
Short Period ◽  
Distinct Sequence

The Fish River Subgroup of the Nama Group, southern Namibia, is restudied in terms of lithostratigraphy and depositional environment. The study is based on partly fine-scaled sections, particularly of the Nababis and Gross Aub Formation. The results are generally in accordance with earlier studies. However, braided river deposits appear to be less widely distributed in the studied area, and a considerable part of the formations of the middle and upper subgroup apparently were deposited under shallowest marine conditions including upper shore-face. Evidence comes partly from sedimentary features and facies distribution, and partly from trace fossils, particularly Skolithos and the characteristic Trichophycus pedum. Environmental conditions represented by layers with T. pedum suggest that the producer favoured shallow marine habitats and transgressive regimes. The successions represent two deepening-upward sequences, both starting as fluvial (braided river) systems and ending as shallow marine tidally dominated environments. The first sequence includes the traditional Stockdale, Breckhorn and lower Nababis formations (Zamnarib Member). The second sequence includes the upper Nababis (Haribes Member) and Gross Aub formations. As a result, the Nababis and Gross Aub formations require emendation: a new formation including the Haribes and Rosenhof and possibly also the Deurstamp members. In addition, four distinct sequence stratigraphic units are deter-minable for the Fish River Subgroup in the southern part of the basin. The Proterozoic–Cambrian transition in southern Namibia is most probably located as low as the middle Schwarzrand Subgroup. The environmentally controlled occurrence of Trichophycus pedum undermines the local stratigraphic significance of this trace fossil which is eponymous with the lowest Cambrian and Phanerozoic trace fossil assemblage on a global scale. However, occurrences of such trace fossils have to be regarded as positive evidence for Phanerozoic age regardless of co-occurring body fossils. Other suggestions strongly dispute the concept of the formal Proterozoic–Cambrian and Precambrian–Phanerozoic boundary. Carbon isotope excursions and radiometric datings for the Nama Group do not help to calibrate precisely the temporal extent of the Fish River Subgroup. Fossil content, sequence stratigraphy and inferred depositional developments suggest that this subgroup represents only a short period of late orogenic molasse sedimentation during the early sub-trilobitic Early Cambrian.

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