CRETACEOUS PALYNOLOGY (SPORES, POLLEN AND DINOFLAGELLATE CYSTS) OF THE SIQEIFA 1-X BOREHOLE, NORTHERN EGYPT

Diverse and well preserved palynofloras were recognized in the Lower Cretaceous succession penetrated by well Siqeifa 1-X in northern Egypt. Dinoflagellate cysts such as Subtilisphaera senegalensis was regarded, with the spores Impardecispora apiverrucata and Aequitriradites spinulosus, as important...

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Main Authors: MAGDY S. MAHMOUD, AMR S. DEAF
Format: Article
Language:English
Published: Milano University Press 2007-07-01
Series:Rivista Italiana di Paleontologia e Stratigrafia
Subjects:
Online Access:https://riviste.unimi.it/index.php/RIPS/article/view/5871
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author MAGDY S. MAHMOUD
AMR S. DEAF
author_facet MAGDY S. MAHMOUD
AMR S. DEAF
author_sort MAGDY S. MAHMOUD
collection DOAJ
description Diverse and well preserved palynofloras were recognized in the Lower Cretaceous succession penetrated by well Siqeifa 1-X in northern Egypt. Dinoflagellate cysts such as Subtilisphaera senegalensis was regarded, with the spores Impardecispora apiverrucata and Aequitriradites spinulosus, as important Berriasian to Barremian species. Afropollis operculatus/zonatus pollen and spores such as Balmeisporites holodictyus, Trilobosporites laevigatus and Duplexisporites generalis are diagnostic of Aptian. The lowest occurrences of the pollen Afropollis jardinus, the spore Crybelosporites pannuceus and elaterates such as Elaterosporites klaszii, Elaterocolpites castelainii and Elateroplicites africaensis characterize the Albian/lower Cenomanian interval. The palynofloras enabled the recognition of five spore-pollen and four dinoflagellate zones, which are correlated with regional records, mainly from Egypt and Libya. The vertical distribution of terrestrial and marine palynomorphs, along with palynodebris, reflects two regressive marginal marine cycles during Berriasian-Barremian and Albian-lower Cenomanian times whereas the Aptian witnessed a transgressive open marine (inner shelf) environment. A warm humid palaeoclimate was inferred during deposition of the investigated succession of the borehole, in contrast to the known warm arid to semi-arid climate, suggested for the Northern Gondwana Realm during Early Cretaceous times. This is probably due to the palaeogeographic position of Egypt during Early Cretaceous times or, to a local reason. Palynofloras from Siqeifa 1-X borehole, with Afropollis pollen and elaterates, are of North African aspect and share the broad characteristics of the "Albian-Cenomanian Elaterates Province" of Herngreen et al. (1996). Abundance of spores and araucariacean pollen are transitional features between those in North Gondwana and Southern Laurasia but, unlikely, typical transitional assemblages lack bisaccates conifers and have Gleicheniaceae spores.
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spelling doaj.art-aaa8539017c846b2a22677b8b35588dc2023-09-02T12:44:13ZengMilano University PressRivista Italiana di Paleontologia e Stratigrafia0035-68832039-49422007-07-01113210.13130/2039-4942/58715187CRETACEOUS PALYNOLOGY (SPORES, POLLEN AND DINOFLAGELLATE CYSTS) OF THE SIQEIFA 1-X BOREHOLE, NORTHERN EGYPTMAGDY S. MAHMOUDAMR S. DEAFDiverse and well preserved palynofloras were recognized in the Lower Cretaceous succession penetrated by well Siqeifa 1-X in northern Egypt. Dinoflagellate cysts such as Subtilisphaera senegalensis was regarded, with the spores Impardecispora apiverrucata and Aequitriradites spinulosus, as important Berriasian to Barremian species. Afropollis operculatus/zonatus pollen and spores such as Balmeisporites holodictyus, Trilobosporites laevigatus and Duplexisporites generalis are diagnostic of Aptian. The lowest occurrences of the pollen Afropollis jardinus, the spore Crybelosporites pannuceus and elaterates such as Elaterosporites klaszii, Elaterocolpites castelainii and Elateroplicites africaensis characterize the Albian/lower Cenomanian interval. The palynofloras enabled the recognition of five spore-pollen and four dinoflagellate zones, which are correlated with regional records, mainly from Egypt and Libya. The vertical distribution of terrestrial and marine palynomorphs, along with palynodebris, reflects two regressive marginal marine cycles during Berriasian-Barremian and Albian-lower Cenomanian times whereas the Aptian witnessed a transgressive open marine (inner shelf) environment. A warm humid palaeoclimate was inferred during deposition of the investigated succession of the borehole, in contrast to the known warm arid to semi-arid climate, suggested for the Northern Gondwana Realm during Early Cretaceous times. This is probably due to the palaeogeographic position of Egypt during Early Cretaceous times or, to a local reason. Palynofloras from Siqeifa 1-X borehole, with Afropollis pollen and elaterates, are of North African aspect and share the broad characteristics of the "Albian-Cenomanian Elaterates Province" of Herngreen et al. (1996). Abundance of spores and araucariacean pollen are transitional features between those in North Gondwana and Southern Laurasia but, unlikely, typical transitional assemblages lack bisaccates conifers and have Gleicheniaceae spores.https://riviste.unimi.it/index.php/RIPS/article/view/5871SporesPollenDinoflagellate cystsAge assessmentsPalynologyLower CretaceousEgypt
spellingShingle MAGDY S. MAHMOUD
AMR S. DEAF
CRETACEOUS PALYNOLOGY (SPORES, POLLEN AND DINOFLAGELLATE CYSTS) OF THE SIQEIFA 1-X BOREHOLE, NORTHERN EGYPT
Rivista Italiana di Paleontologia e Stratigrafia
Spores
Pollen
Dinoflagellate cysts
Age assessments
Palynology
Lower Cretaceous
Egypt
title CRETACEOUS PALYNOLOGY (SPORES, POLLEN AND DINOFLAGELLATE CYSTS) OF THE SIQEIFA 1-X BOREHOLE, NORTHERN EGYPT
title_full CRETACEOUS PALYNOLOGY (SPORES, POLLEN AND DINOFLAGELLATE CYSTS) OF THE SIQEIFA 1-X BOREHOLE, NORTHERN EGYPT
title_fullStr CRETACEOUS PALYNOLOGY (SPORES, POLLEN AND DINOFLAGELLATE CYSTS) OF THE SIQEIFA 1-X BOREHOLE, NORTHERN EGYPT
title_full_unstemmed CRETACEOUS PALYNOLOGY (SPORES, POLLEN AND DINOFLAGELLATE CYSTS) OF THE SIQEIFA 1-X BOREHOLE, NORTHERN EGYPT
title_short CRETACEOUS PALYNOLOGY (SPORES, POLLEN AND DINOFLAGELLATE CYSTS) OF THE SIQEIFA 1-X BOREHOLE, NORTHERN EGYPT
title_sort cretaceous palynology spores pollen and dinoflagellate cysts of the siqeifa 1 x borehole northern egypt
topic Spores
Pollen
Dinoflagellate cysts
Age assessments
Palynology
Lower Cretaceous
Egypt
url https://riviste.unimi.it/index.php/RIPS/article/view/5871
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