Research paper
Climate-controlled palynofacies and miospore stratigraphy of the Jauf Formation, Lower Devonian, northern Saudi Arabia

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Abstract

The Jauf Formation miospore succession is synthesized in terms of palaeoenvironments and sequence stratigraphy. The data set for this study is obtained from four overlapping, continuously cored, and extensively sampled, boreholes that form a 940 ft (287 m) composite section. The Jauf Formation ranges in age from late Pragian to latest Emsian. The palynological assemblages, recognized herein, provide the basis for recognizing depositional environments present in the Lower Devonian of northern Saudi Arabia. Transgressive–regressive cycles are indicated not only by lithology, but also by marked changes in the marine to terrestrially dominated palynological assemblages, which are described in detail. Flooding events are recognized by the replacement of spore-dominated assemblages by organic-walled microphytoplankton and could be climate-controlled. The maximum flooding interval for the Jauf Formation is reinterpreted based on a correlative event consisting of diverse acritarchs and abundant chitinozoans. The sequence of palynological assemblages corresponds to fourth order cycles in the Hammamiyat Member. The new northern Gondwanan biozonation developed by Breuer and Steemans (2013) and used here allows a high-resolution regional biozonation for the Arabian Plate and larger-scale correlation of the Jauf Formation with other Gondwanan and Euramerican localities. One new spore genus (Zonohilates) and four new spore species (Insculptospora maxima, Camarozonotriletes alruwailii, Devonomonoletes crassus and Zonohilates vulneratus) are proposed.

Introduction

Dispersed plant spores are the primary tool used for biostratigraphic age determination and correlation of the Devonian deposits of Saudi Arabia supplementing marine faunas that are confined to Jauf Formation outcrops (e.g. Boucot et al., 1989, Forey et al., 1992). More than a decade ago, Saudi Aramco drilled a number of shallow core holes in northern Saudi Arabia with the intention of studying the Devonian deposits of this area and correlating them to the nearby outcrops. Leszczyński et al. (2010) described the sedimentology of two pairs of core holes located ca. 350 km apart (Fig. 1), and documented the bioturbation and sedimentological structures present in the Jauf Formation (Fig. 2, Fig. 3). The JNDL-3 and JNDL-4 core holes are located in the vicinity of Domat Al-Jandal while BAQA-1 and BAQA-2 are near the town of Baq'a. The Jauf Formation in northern Saudi Arabia is divided into five members based on lithofacies. The lower part of formation occurs in the BAQA core holes whereas its upper part occurs in JNDL-3 and JNDL-4. Stratigraphic overlap of the cores gives a complete composite Jauf Formation succession (942 ft/287 m thick) and includes all members (Fig. 4).

These core holes were studied palynologically to establish a detailed Devonian biostratigraphy and correlate with subsurface sections from eastern Saudi Arabia (Breuer et al., 2005, Breuer et al., 2007, Breuer and Steemans, 2013). Palynological slides from previous studies were re-examined and complemented by newly processed samples and observations. This paper represents the synthesis for the spore-based stratigraphy of the Jauf Formation in northern Saudi Arabia. Although the majority of spore species from the studied assemblages were described by Breuer et al. (2007) and Breuer and Steemans (2013), some are new and described below in the Systematic Palaeontology. Finally the results of the quantitative study carried out on palynological assemblages are presented herein and palaeoenvironments are discussed regarding the detailed sedimentological study of the sections by Leszczyński et al. (2010).

Section snippets

Jauf Formation

The Jauf Formation is exposed in northern Saudi Arabia (Powers, 1968). The formation is described in the explanatory notes of several geological quadrangle maps where it is present (Vaslet et al., 1987, Wallace et al., 1996, Wallace et al., 1997, Janjou et al., 1997a, Janjou et al., 1997b, Lebret et al., 1999). The Jauf Formation in outcrop was also studied by Helal (1965), Bahafzallah et al. (1981), Al-Laboun, 1982, Al-Laboun, 1986 and Al-Husseini and Matthews (2006). Macrofauna from the Jauf

Review of palynological studies

Loboziak and Streel (1995) were the first to publish palynological results from the Jauf Formation in northern Saudi Arabia. Based on taxa common to Euramerica, they applied the Devonian spore zonation developed for Western Europe by Streel et al. (1987) for the TRBH-1 borehole. They assigned the spore assemblages from the uppermost Tawil and lower Jauf formations to the Emsian, while the lower part of the Tawil Formation was dated as Late Silurian to Early Lochkovian (Steemans, 1995). Higher

Description of the palynological assemblages

Abundant and well-preserved palynomorphs were recovered from throughout the investigated Jauf sections. Most assemblages contain a mixture of terrestrial (spores, phytodebris and freshwater algae) and marine elements (acritarchs, prasinophytes, scolecodonts and very rarely chitinozoans). Some assemblages are dominated by spores and phytodebris, with marine elements generally rare or totally absent. Others are dominated by sphaeromorphs and/or acritarchs. In rare instances freshwater coenobial

Biostratigraphy

Most studied assemblages have an abundant and diverse spore component. Spores are the most useful biostratigraphic tool for dating and correlation of the Saudi Arabian Early Devonian deposits, although the rare occurrences of chitinozoans are also useful. Acritarchs, however locally abundant, were not studied in detail and will be the subject of a future paper.

The stratigraphic palynology of the Jauf Formation presented in Breuer et al., 2005, Breuer et al., 2007 was principally based on

Data

In the Early Devonian section represented by the BAQA-1 and BAQA-2 core holes the secondary dolomitic portion of the Qasr Member contains numerous acritarch specimens and the number of miospore species is drastically reduced compared to the assemblages from the Sha'iba Member. The environment of deposition for this dolomitic interval is interpreted to be lagoonal. Among the miospore species that disappear during Qasr time, many reappear progressively in the overlying siliciclastic sediments,

Conclusions

This paper synthesizes the results of palynological studies begun some time ago (Breuer et al., 2005, Breuer et al., 2007, Breuer and Steemans, 2013) to refine the age of the Jauf Formation in northwestern Saudi Arabia. The new northern Gondwanan biozonation developed in Breuer and Steemans (2013) allows a fine regional correlation and larger-scale correlation with Gondwanan and Euramerican localities. Troth et al. (2011) showed that key spore used zonally in both Laurussia and Gondwana do not

Acknowledgments

The authors would like to express their gratitude to management of the Saudi Arabian Ministry of Petroleum and Mineral Resources and the Saudi Arabian Oil Company (Saudi Aramco) for granting permission to publish this paper. They also acknowledge M. Giraldo-Mezzatesta and Prof. F. Boulvain (Liège University, Belgium) respectively for the preparation of palynological slides and comments on the depositional model presented herein. Thanks are especially expressed to Dr. B. Owens and an anonymous

References (74)

  • S.A. Al-Hajri et al.

    Stratigraphic Palynology of the Palaeozoic of Saudi Arabia

  • S.A. Al-Hajri et al.

    Stratigraphy and operational palynology of the Devonian System in Saudi Arabia

    GeoArabia

    (1999)
  • M.I. Al-Husseini et al.

    Arabian orbital stratigraphy: second-order sequence boundaries?

    GeoArabia

    (2005)
  • M.I. Al-Husseini et al.

    Devonian Jauf Formation, Saudi Arabia: orbital second-order Depositional Sequence 28

    GeoArabia

    (2006)
  • A.A. Al-Laboun

    The subsurface stratigraphy of the pre-Khuff formations in central and northwestern Arabia

    Faculty of Earth Sciences

    (1982)
  • A.A. Al-Laboun

    Stratigraphy and hydrocarbon potential of the Paleozoic succession in both Tabuk and Widyan basins, Arabia

  • K.C. Allen

    Lower to Middle Devonian spores of North and Central Vestspitsbergen

    Palaeontology

    (1965)
  • A.D. Arkhangelskaya

    Zonal spore assemblages and stratigraphy of the Lower and Middle Devonian in the Russian Plate

  • A. Bahafzallah et al.

    Stratigraphy and facies of the Devonian Jauf Formation, Saudi Arabia

    N. Jb. Geol. Paläont. (Monatsh.)

    (1981)
  • B.E. Balme et al.

    Upper Devonian spores from the Canning Basin, Western Australia

    Micropaleontology

    (1962)
  • A.J. Boucot et al.

    New Devonian fossils from Saudi Arabia and their biogeographical affinities

    Senckenb. Lethaea

    (1989)
  • P. Breuer

    Devonian miospore palynology in Western Gondwana: an application to oil exploration

    (2007)
  • P. Breuer et al.

    Devonian spore assemblages from northwestern Gondwana: taxonomy and biostratigraphy

    Spec. Pap. Palaeontol.

    (2013)
  • P. Breuer et al.

    Stratigraphic palynology of Devonian boreholes from northern Saudi Arabia

  • N.D. Burgess et al.

    Silurian cryptospores and spores from the type Wenlock area, Shropshire, England

    Palaeontology

    (1991)
  • P.L. Forey et al.

    Lower Devonian fishes from Saudi Arabia

    Bull. Br. Mus. Nat. Hist. (Geol.)

    (1992)
  • Y. Grahn

    Devonian chitinozoan biozones of Western Gondwana

    Acta Geol. Pol.

    (2005)
  • Y. Grahn et al.

    The Furnas/Ponta Grossa contact and the age of the lowermost Ponta Grossa Formation in the Apucarana Sub-basin (Paraná Basin, Brazil): integrated palynological age determination

    Rev. Bras. Paleontol.

    (2010)
  • D. Grignani et al.

    Palaeozoic and Mesozoic subsurface palynostratigraphy in the Al Khufrah Basin, Libya

  • A.H. Helal

    General geology and lithostratigraphic subdivision of the Devonian rocks of the Jauf area, Saudi Arabia

    N. Jb. Geol. Paläont. (Monatsh.)

    (1965)
  • A.C. Ibrahim

    Sporenformen des Ägirhorizontes des Ruhrreviers

    (1933)
  • A.M. Ishchenko

    Atlas of the microspores and pollen of the Middle Carboniferous of the western part of the Donetz Basin

  • Janjou, D., Halawani, M.A., Al-Muallem, M.S., Robelin, C., Brosse, J.-M., Courbouleix, S., Dagain, J., Genna, A.,...
  • Janjou, D., Halawani, M.A., Brosse, J.-M., Al-Muallem, M.S., Becq-Giraudon, J.F., Dagain, J., Genna, A., Razin, P.,...
  • G. Konert et al.

    Paleozoic stratigraphy and hydrocarbon habitat of the Arabian Plate

    GeoArabia

    (2001)
  • E.P. Lanninger

    Sporen-Gesellschaften aus dem Ems der SW-Eifel (Rheinisches Schiefergebirge)

    Palaeontogr. Abt. B

    (1968)
  • Lebret, P., Halawani, M.A., Memesh, A., Bourdillon, C., Janjou, D., Le Nindre, Y.-M., Roger, J., Shorbaji, H., Kurdi,...
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