scholarly journals The Geographic, Environmental and Phylogenetic Evolution of the Alveolinoidea from the Cretaceous to the Present Day.

2020 ◽  
Author(s):  
Marcelle Boudagher-Fadel ◽  
Geoffrey David Price
Keyword(s):  
Sea Level ◽  
Convergent Evolution ◽  
Systematic Analysis ◽  
Larger Benthic Foraminifera ◽  
Shallow Marine ◽  
Marine Carbonates ◽  
New Material ◽  
Phylogenetic Evolution ◽  
Global Sea Level ◽  
First Time

The superfamily Alveolinoidea is a member of the Order Miliolida, and is comprised of three main families, the Alveolinidae, the Fabulariidae and the Rhapydioninidae. They are examples of Larger Benthic Foraminifera (LBF), which are single cell organisms with specific characteristic endoskeletons. Alveolinoids are found globally from the Cretaceous to present day and are very important biostratigraphic index fossils in shallow-marine carbonates. They are often associated with significant hydrocarbon reservoirs, and exhibit provincialism with characteristic genera often confined to one of the American, Tethyan or Indo-Pacific provinces. Previously, the systematic study of the global interrelationship between the various alveolinoid lineages has not been possible because of the absence of biostratigraphic correlation between the geographically scattered assemblages, and the scarcity of described material from the Indo-Pacific province. Here we use the literature and new material from the Americas, the French Alps, Iran, Tibet, India and SE Asia, coupled with the use the planktonic foraminiferal zonal (PZ) correlation scheme to put forward, for the very first time, a comprehensive, global, systematic analysis of the biostratigraphic, phylogenetic and palaeogeographic evolution of the alveolinoids. The alveolinoids originated in the Cretaceous in the Tethyan province. During a global sea-level low-stand, a westward migration of some alveolinoids species to the Americas occurred in this period, a behaviour also seen in previous studies of contemporaneous orbitolinid LBF. After the K-P event, which saw the extinction of all Cretaceous alveolinoids, rare new forms of alveolinoids evolved again, first in the Americas and later independently in Tethys. As found in previous studies of rotalid LBF, sea-level low-stands in the Paleocene also allowed some alveolinoid forms to migrate, but this time in an eastward direction from the Americas to Tethys, and from Tethys on to the Indo-Pacific. Alveolinoids still exist today ( Borelis and Alveolinella ), the former of which is cosmopolitan, while the latter is restricted to the Indo-Pacific province. Throughout their phylogenetic history alveolinoids characteristically exhibit convergent evolution, with the repeated re-occurrence of certain morphological features. Understanding this propensity to homoplasy is essential in understanding and constructing the phylogenetic relationships within the alveolinoid superfamily.

scholarly journals The Geographic, Environmental and Phylogenetic Evolution of the Alveolinoidea from the Cretaceous to the Present Day.

2020 ◽  
Author(s):  
Marcelle Boudagher-Fadel ◽  
Geoffrey David Price
Keyword(s):  
Sea Level ◽  
Convergent Evolution ◽  
Systematic Analysis ◽  
Larger Benthic Foraminifera ◽  
Shallow Marine ◽  
Marine Carbonates ◽  
New Material ◽  
Phylogenetic Evolution ◽  
Global Sea Level ◽  
First Time

The superfamily Alveolinoidea is a member of the Order Miliolida, and is comprised of three main families, the Alveolinidae, the Fabulariidae and the Rhapydioninidae. They are examples of Larger Benthic Foraminifera (LBF), which are single cell organisms with specific characteristic endoskeletons. Alveolinoids are found globally from the Cretaceous to present day and are very important biostratigraphic index fossils in shallow-marine carbonates. They are often associated with significant hydrocarbon reservoirs, and exhibit provincialism with characteristic genera often confined to one of the American, Tethyan or Indo-Pacific provinces. Previously, the systematic study of the global interrelationship between the various alveolinoid lineages has not been possible because of the absence of biostratigraphic correlation between the geographically scattered assemblages, and the scarcity of described material from the Indo-Pacific province. Here we use the literature and new material from the Americas, the French Alps, Iran, Tibet, India and SE Asia, coupled with the use the planktonic foraminiferal zonal (PZ) correlation scheme to put forward, for the very first time, a comprehensive, global, systematic analysis of the biostratigraphic, phylogenetic and palaeogeographic evolution of the alveolinoids. The alveolinoids originated in the Cretaceous in the Tethyan province. During a global sea-level low-stand, a westward migration of some alveolinoids species to the Americas occurred in this period, a behaviour also seen in previous studies of contemporaneous orbitolinid LBF. After the K-P event, which saw the extinction of all Cretaceous alveolinoids, rare new forms of alveolinoids evolved again, first in the Americas and later independently in Tethys. As found in previous studies of rotalid LBF, sea-level low-stands in the Paleocene also allowed some alveolinoid forms to migrate, but this time in an eastward direction from the Americas to Tethys, and from Tethys on to the Indo-Pacific. Alveolinoids still exist today ( Borelis and Alveolinella ), the former of which is cosmopolitan, while the latter is restricted to the Indo-Pacific province. Throughout their phylogenetic history alveolinoids characteristically exhibit convergent evolution, with the repeated re-occurrence of certain morphological features. Understanding this propensity to homoplasy is essential in understanding and constructing the phylogenetic relationships within the alveolinoid superfamily.

scholarly journals The Geographic, Environmental and Phylogenetic Evolution of the Alveolinoidea from the Cretaceous to the Present Day.

2021 ◽  
Author(s):  
Marcelle Boudagher-Fadel ◽  
Geoffrey David Price
Keyword(s):  
Sea Level ◽  
Convergent Evolution ◽  
Systematic Analysis ◽  
Larger Benthic Foraminifera ◽  
Shallow Marine ◽  
Marine Carbonates ◽  
New Material ◽  
Phylogenetic Evolution ◽  
Global Sea Level ◽  
First Time

The superfamily Alveolinoidea is a member of the Order Miliolida, and is comprised of three main families, the Alveolinidae, the Fabulariidae and the Rhapydioninidae. They are examples of Larger Benthic Foraminifera (LBF), which are single cell organisms with specific characteristic endoskeletons. Alveolinoids are found globally from the Cretaceous to present day and are very important biostratigraphic index fossils in shallow-marine carbonates. They are often associated with significant hydrocarbon reservoirs, and exhibit provincialism with characteristic genera often confined to one of the American, Tethyan or Indo-Pacific provinces. Previously, the systematic study of the global interrelationship between the various alveolinoid lineages has not been possible because of the absence of biostratigraphic correlation between the geographically scattered assemblages, and the scarcity of described material from the Indo-Pacific province. Here we use the literature and new material from the Americas, the French Alps, Iran, Tibet, India and SE Asia, coupled with the use the planktonic foraminiferal zonal (PZ) correlation scheme to put forward, for the very first time, a comprehensive, global, systematic analysis of the biostratigraphic, phylogenetic and palaeogeographic evolution of the alveolinoids. The alveolinoids originated in the Cretaceous in the Tethyan province. During a global sea-level low-stand, a westward migration of some alveolinoids species to the Americas occurred in this period, a behaviour also seen in previous studies of contemporaneous orbitolinid LBF. After the K-P event, which saw the extinction of all Cretaceous alveolinoids, rare new forms of alveolinoids evolved again, first in the Americas and later independently in Tethys. As found in previous studies of rotalid LBF, sea-level low-stands in the Paleocene also allowed some alveolinoid forms to migrate, but this time in an eastward direction from the Americas to Tethys, and from Tethys on to the Indo-Pacific. Alveolinoids still exist today ( Borelis and Alveolinella), the former of which is cosmopolitan, while the latter is restricted to the Indo-Pacific province. Throughout their phylogenetic history alveolinoids characteristically exhibit convergent evolution, with the repeated re-occurrence of certain morphological features. Understanding this propensity to homoplasy is essential in understanding and constructing the phylogenetic relationships within the alveolinoid superfamily.

scholarly journals The geographic, environmental and phylogenetic evolution of the Alveolinoidea from the Cretaceous to the present day

2021 ◽  
Vol 2 ◽  
Author(s):  
Marcelle K. BouDagher-Fadel ◽  
Geoffrey David Price
Keyword(s):  
Sea Level ◽  
Convergent Evolution ◽  
South East Asia ◽  
Systematic Analysis ◽  
Larger Benthic Foraminifera ◽  
Shallow Marine ◽  
Marine Carbonates ◽  
New Material ◽  
Phylogenetic Evolution ◽  
Global Sea Level

The superfamily Alveolinoidea is a member of the Order Miliolida, and comprises three main families, the Alveolinidae, the Fabulariidae and the Rhapydioninidae. They are examples of Larger benthic foraminifera (LBF), which are single-celled organisms with specific characteristic endoskeletons. Alveolinoids are found globally from the Cretaceous to the present day, and are important biostratigraphic index fossils in shallow-marine carbonates. They are often associated with hydrocarbon reservoirs, and exhibit provincialism with characteristic genera often confined to one of the American, Tethyan or Indo-Pacific provinces. Previously, the systematic study of the global interrelationship between the various alveolinoid lineages has not been possible because of the absence of biostratigraphic correlation between the geographically scattered assemblages, and the scarcity of described material from the Indo-Pacific province. Here we use the literature and new material from the Americas, the French Alps, Iran, Tibet, India and South East Asia, coupled with the use of the planktonic foraminiferal zonal (PZ) correlation scheme to propose a comprehensive, global, systematic analysis of the biostratigraphic, phylogenetic and paleogeographic evolution of the alveolinoids. The alveolinoids originated in the Cretaceous in the Tethyan province. During a global sea-level low stand, a westward migration of some alveolinoids species to the Americas occurred, a behaviour previously reported in contemporaneous orbitolinid LBF. After the Cretaceous/Palaeogene (K–P) event, which saw the extinction of all Cretaceous alveolinoids, rare new forms of alveolinoids evolved again, first in the Americas and later independently in Tethys. As was found in previous studies of rotalid LBF, sea-level low stands in the Paleocene also allowed some alveolinoid forms to migrate, but this time in an eastward direction from the Americas to Tethys, and from Tethys on to the Indo-Pacific province. Alveolinoids still exist today (BorelisandAlveolinella), the former of which is cosmopolitan, while the latter is restricted to the Indo-Pacific province. Throughout their phylogenetic history, alveolinoids characteristically exhibit convergent evolution, with the repeated re-occurrence of certain morphological features. Understanding this propensity to homoplasy is essential in understanding and constructing the phylogenetic relationships within the alveolinoid superfamily.

A new molluscan assemblage from the pre-evaporitic Messinian of Crete (Greece)

2020 ◽  
Author(s):  
Efterpi Koskeridou ◽  
Danae Thivaiou
Keyword(s):  
Seagrass Beds ◽  
Shallow Marine ◽  
Environmental Consequences ◽  
Environmental Perturbation ◽  
New Material ◽  
Molluscan Fauna ◽  
First Time ◽  
Molluscan Assemblage ◽  
Hard Substrates ◽  
Normal Salinity

<p>The Messinian Salinity Crisis (MSC) was an environmental perturbation with dramatic environmental consequences that greatly affected marine organisms. Messinian deposits are found in several locations around the Mediterranean, but few offer marine faunas rich in molluscs. A section near Heraklion, central Crete, has provided new material that contains a well preserved and rich molluscan fauna that includes many micromorphic species. The section is of early Messinian age, belongs to Agios Miron Formation, and bears several layers of fossiliferous marly sands.</p><p>Molluscs from a fossiliferous bed of the section are presented here for the first time. Gastropods and bivalves are most common, but scaphopods and chitons are not infrequent. The assemblage seems to be composed of transported elements from nearby environments and the most frequent species are present in comparable abundances for gastropods and bivalves. The gastropod fauna is represented by <em>Bittium</em> sp. and <em>Gibbula </em>sp., accompanied by <em>Diodora</em> cf. <em>graeca</em>, <em>Turritella</em> sp., <em>Jujubinus</em> sp., species of Pyramidellidae and rarer <em>Homalopoma</em> sp. and Haliotis sp. The presence of <em>Bittium</em> sp. together with <em>Jujubinus</em> sp. suggests vegetated environments. Bivalves are represented by species dwelling mostly in sandy environments such as <em>Glycymeris</em> cf. <em>inflata</em> (also occurring in larger specimens), <em>Spisula</em> sp., <em>Timoclea</em> sp. and various cardiids. Exceptionally well-preserved chitons indicate the presence of hard substrates such as rocks, pebbles or roots of seagrass beds. This is confirmed by the presence of the gastropods <em>Diodora</em> cf. <em>graeca</em> and <em>Haliotis</em> sp.</p><p>The assemblage points towards normal salinity shallow marine conditions of sandy bottoms with patches of seagrass-type vegetation before the onset of the MSC.</p>

Benthic foraminifera from the Albian shallow-marine limestones in the Geyik Dağı area (Central Taurides), southern Turkey

2021 ◽  
pp. 1-21
Author(s):  
Cemile Solak ◽  
Kemal Taslı ◽  
Hayati Koç
Keyword(s):  
Benthic Foraminifera ◽  
Carbonate Platform ◽  
Larger Benthic Foraminifera ◽  
Shallow Marine ◽  
Southern Turkey ◽  
Lowermost Part ◽  
First Time ◽  
High Diversity ◽  
Open Shelf

Abstract Cretaceous carbonates in the Geyik Dağı area (Central Taurides, southern Turkey) are represented by two successions with different paleoenvironmental settings: open shelf to slope succession of Cenomanian to Danian age and inner platform succession of Albian to Maastrichtian age, which is interrupted by a post-Cenomanian disconformity. Outcropped lowermost part of the platform-type one is composed of rudistid limestones corresponding to the Urgonian-type carbonates and belongs to the Geyik Dağı Unit (=Anamas-Akseki Carbonate Platform). It contains a rich assemblage of larger benthic foraminifera including orbitolinid, chrysalidinid, cuneolinid, nezzazatid, and miliolid taxa, which has been illustrated and documented here for the first time from the upper Albian of the Tauride Carbonate Platform. The occurrence of such a diversified foraminiferal fauna indicates a prominent high diversity that took place in the Tauride Carbonate Platform during the late Albian time, which corresponds to a major emersion period in some parts of the platform.

scholarly journals An assessment of the influence of orbital forcing on Late Pliocene global sea-level using a shallow-marine sedimentary record from the Wanganui Basin, New Zealand

2021 ◽  
Author(s):  
◽  
Juliet Perry Sefton
Keyword(s):  
New Zealand ◽  
Sea Level ◽  
Benthic Foraminifera ◽  
Volume Changes ◽  
Shallow Marine ◽  
Late Pliocene ◽  
Ice Volume ◽  
Global Ice Volume ◽  
Global Sea Level ◽  
Water Depths

<p>Classical Milankovitch Theory suggests variance in the orbital cycles of precession (21,000 year) modulated by eccentricity (~100,000 year) and obliquity (41,000 year) should have a profound influence on polar insolation and ice volume. However, the globally-integrated ice volume proxy record (benthic δ¹⁸O) during the Late Pliocene (3.0-2.6 Ma) is dominated by obliquity-paced cycles, and lacks a significant precession component. A number of conceptual hypotheses have been proposed to explain this “41,000 year problem”, but palaeoclimate records independent of the benthic δ¹⁸O record are required to test these hypotheses.  The Wanganui Basin, New Zealand, contains a well-dated, shallow-marine Neogene sedimentary succession that is widely recognised as an important site for examining sea-level/ice volume changes at orbital frequencies. In this study, the shallow-marine Late Pliocene Mangaweka Mudstone is examined at an orbital-scale resolution (~3-5 kyr sampling) along a continuous 672 metre thick (true thickness) outcropping road section on Watershed Road between the Rangitikei and Turakina River valleys.  Two modern analogue-calibrated water depth proxies were used to evaluate palaeobathymetric changes: (i) sediment texture and (ii) benthic foraminifera census data. An overall trend of shallowing to inner-shelf water depths occurs up-section, but is superimposed by higher frequency fluctuations. For the lowermost ~400 metres of the section, in situ benthic foraminifera assemblages indicate water depths >100 metres. As wave-induced sand transport does not occur on the modern Manawatu-Wanganui outer-shelf, and modern wave climates are assumed to be analogous to the Pliocene, it is concluded that the sediment grainsize approach is not an appropriate proxy for reconstruction water depth changes in the lower ~400 metres of section.  An integrated magneto-, bio- and tephrostratigraphy was developed that constrains the outcrop succession to between ~3.0 Ma and 2.58 Ma. Nine distinct cycles spanning ~400,000 years are identified in the grainsize and benthic foraminifera assemblages. Within the uncertainty of the age model, the Mangaweka Mudstone grainsize cycles can be matched one-for-one to the δ¹⁸O glacial-interglacial cycles, as they display a similar pattern in terms of frequency and amplitude. The frequency of the Mangaweka Mudstone cycles (and the corresponding interval in the benthic δ¹⁸O record) are dominated by the ~40,000 year obliquity cycle, but with a subordinate eccentricity component. Therefore, the fluctuations in the grainsize and benthic foraminifera proxies likely represent an indirect response to global sea-level fluctuations via their effect on continental shelf sediment transport mechanisms (non-wave) with the orbitally-paced transgression and regression of the shoreline on a restricted palaeo- continental shelf.  The implications for the orbital theory of the ice ages are that during the Late Pliocene, global ice volume changes responded primarily to obliquity, and the precession influences were either: (i) too low in amplitude to have influenced the grainsize and benthic foraminifera assemblages in the Mangaweka Mudstone depositional environment, or (ii) cancelled-out in global ice volume and sea-level changes because precession forcing is anti-phased between the hemispheres.</p>

scholarly journals Foraminiferal Biostratigraphy and Palaeoenvironmental Analysis of the Mid-cretaceous Limestones in the Southern Tibetan Plateau

2017 ◽  
Vol 47 (2) ◽  
pp. 188-207 ◽  
Author(s):  
Marcelle K. BouDagher-Fadel ◽  
Xiumian Hu ◽  
G. David Price ◽  
Gaoyuan Sun ◽  
Jian-Gang Wang ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Planktonic Foraminifera ◽  
Level Variation ◽  
Larger Benthic Foraminifera ◽  
Sedimentary Sequences ◽  
Sea Level Variation ◽  
Southern Tibetan Plateau ◽  
Global Sea Level ◽  
First Time ◽  
Almost Continuous

Abstract This study of mid-Cretaceous foraminifera from the Linzhou, the Coqen and the Xigaze Basins in the southern Tibetan Plateau has provided the first high resolution biostratigraphic description of these limestones and interpretation of their paleoenvironmental settings. The fossil assemblages are dominated primarily by orbitolinid larger benthic foraminifera. We reassessed the identification of many taxa, dividing the South Tibetan sedimentary successions of Aptian to Early Cenomanian age into eight new foraminiferal biozones (TLK1 a–h): (i) (TLK1a) a shallow reefal environment corresponding to planktonic foraminifera zone (PZ) Aptian 1–2, dominated by Palorbitolina and Praeorbitolina spp.; (ii) (TLK1b) a transgressive, reefal to forereefal environment corresponding to PZ Aptian 3, characterized by the first appearance of Mesorbitolina parva; (iii) (TLK1c) a shallow reefal to backreef environment of Late Aptian (PZ Aptian 4) age, characterized by the first appearance of Mesorbitolina texana; (iv) (TLK1d) a transgressive phase of forereef to an inner neritic environment of Albian (PZ Albian 1) age, characterized by the first appearance of Cuneolina pavonia; (v) (TLKe) an open-marine reefal environment of Albian (PZ Albian 2) age, with assemblages dominated by flat to slightly conical orbitolinids, characterized by the first appearance of Palorbitolinoides hedini; (vi) (TLK1f) a shallow, open-marine reefal to forereef environment of Middle Albian (PZ Albian 3) age, dominated by flat and convex orbitolinids, and characterized by the first appearance of Mesorbitolina aperta; (vii) (TLK1g) a reefal to forereef environment of end Albian (PZ Albian 4) age, characterized by the appearance of Conicorbitolina cf. cuvillieri and Pseudochoffatella cuvillieri, and in which Early Aptian species of Praeorbitolina cf. wienandsi have been recorded for the first time from the Late Albian; (viii) (TLK1h) a shallow reefal environment of Early Cenomanian age characterized by the first appearance of Conicorbitolina sp. A and Nezzazata conica. The eight new biozones provided biostratigraphic correlation of the Langshan, Sangzugang and Takena Formations in the Lhasa terrane, while the observed evolution of the environmentally controlled microfacies corresponds closely with the current, inferred global sea-level variation of the period. The almost continuous sedimentary sequences studied allowed previously defined orbitolinid phylogenetic linages to be confirmed.

scholarly journals The Paleogeographic Evolution of the Orthophragminids of the Paleogene

2017 ◽  
Vol 47 (4) ◽  
pp. 337-357 ◽  
Author(s):  
Marcelle K. BouDagher-Fadel ◽  
G. David Price
Keyword(s):  
South Africa ◽  
South African ◽  
Planktonic Foraminifera ◽  
Late Eocene ◽  
Larger Benthic Foraminifera ◽  
The Pacific ◽  
West African Coast ◽  
New Material ◽  
Global Sea Level ◽  
Definition Of

Abstract Orthophragminids are larger benthic foraminifera (LBF) and, together with the nummulitids, were the major rock-forming foraminifera from the middle Paleocene to the late Eocene. Today, porous, LBF-bearing, Paleogene limestones, which occur globally from the Pacific and Atlantic margins of the Americas to the Indo-Pacific, form potentially valuable oil reservoirs, and their biota have formed the basis of the definition of three paleobiogeographic provinces, namely those of the Americas, Tethys, and the Indo-Pacific. The orthophragminids of the western part of the Tethyan Province have been studied extensively, however, the other provinces are less well characterized, and until now the origin and paleogeographic development of this group have not been fully articulated. New material described here allows the clear definition of a fourth, South African paleobiogeographic province, and, when combined with refined biostratigraphic dating based on new material from the Americas, Europe, South Asia and SE Asia, enables their paleogeographic and biostratigraphic evolution to be determined. Critically, the occurrence of cosmopolitan planktonic foraminifera (PF) within LBF assemblages enables the first occurrences of various LBF forms within each province to be dated relative to well-calibrated planktonic zones (PZ). From this, we infer that, like the previously studied lepidocyclinids and nummulitids, the orthophragminids originated in the Americas during the Paleocene, probably between the late Danian (PZ P1c, 63.5 Ma) and the early Selandian (PZ P3a, 61.6 Ma). By the middle Paleocene, the orthophragminids had migrated across the Atlantic to the previously isolated West African coast at the extreme of Tethys, probably during global sea-level low stands at 60.3 Ma and again at 56.4 Ma. Subsequently, the American Province again became isolated. In the Tethys, the orthophragminid migrations followed two paths: northeastward through the Tethyan corridor in the late Paleo-cene (Thanetian), and south in the earliest Eocene (Ypresian) to South Africa. The Tethyan forms evolved during the Eocene into many lineages, which in turn migrated, after a few million years of their first appearances into the Indo-Pacific, where they again became isolated and diversified further. Meanwhile the South African forms remained similar to their American ancestors in both small size and external ornamentation, while their internal evolution closely followed that of Tethys forms, as exhibited by three species of Nemkovella and Discocyclina described here from South Africa (Nemkovella mcmilliana n. sp., Discocyclina davyi n. sp. and D. africana n. sp.).

scholarly journals Age, microfacies and depositional environment of the Middle to Late Paleocene shallow-marine carbonates in the Sirt Basin of Libya (Upper Sabil Formation): “Are Intisar domal structures pinnacle reefs?”

Facies ◽  
2021 ◽  
Vol 67 (4) ◽  
Author(s):  
A. Vršič ◽  
H.-J. Gawlick ◽  
F. Schlagintweit ◽  
E. Machaniec ◽  
M. Gharsalla
Keyword(s):  
Depositional Environment ◽  
Planktonic Foraminifera ◽  
Carbonate Ramp ◽  
Larger Benthic Foraminifera ◽  
Shallow Marine ◽  
Late Paleocene ◽  
Marine Carbonates ◽  
Domal Structure ◽  
Sirt Basin

AbstractIn the central-eastern Sirt Basin, enigmatic Intisar domal structures host significant hydrocarbon accumulations. These structures have been commonly interpreted as pinnacle reefs/bioherms occurring in the open-marine basinal environment. Generally, pinnacle reefs/bioherms are mainly characterized by in situ carbonates. The current study challenges the Intisar pinnacle reef/bioherm model by examining one of the domal structures in terms of biostratigraphy, microfacies and depositional environment. These structures were dated using larger benthic foraminifera, which yielded a Middle to Late Paleocene age (Selandian–Early Thanetian). Thirteen microfacies types representing different carbonate ramp environments ranging from outer ramp to inner ramp, were defined. Outer ramp deposits have been observed adjacent to the domal structure, represented mainly by wackestone with small benthic and planktonic foraminifera. The outer ramp deposits are most likely isochronous to the domal structures. The lower part of the domal structures is composed mainly of foraminiferal–algal–echinodermal packstones. The upper part is characterized by foraminiferal–algal–echinodermal packstones with intercalated microbialite–coral boundstones. The euphotic inner ramp deposits are preserved on the crest of the domal structure, consisting of grainstone and packstone rich in Glomalveolina. As a result of this study, the Intisar domal structures are seen as erosional relics of a carbonate ramp and no evidence for pinnacle reef/bioherm model was found.

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