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Palynology of the Devonian
Jauf Formation from the
northern part of Saudi Arabia
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Mansour Al-Ruwaili, Saudi Aramco, Saudi Arabia
Pierre Breuer, University of Liège, Belgium
Ken Higgs, University of Cork, Ireland
Philippe Steemans, University of Liège, Belgium
Charles Wellman, University of Sheffield, UK
Location of the boreholes
After Loboziak, 2000
1700 feet or 520 m
Stratigraphic position of the
boreholes
Y1
Y3
Y4
X1
X2
After Loboziak, 2000
After Al-Hajri et al., 1999
Palynological assemblages
Palynological assemblages
Continental palynomorphs
• Palynological
assemblages are
strongly dominated by
miospores (abundant
trilete/monolete
spores, and less
frequent cryptospores)
Palynological assemblages
Marine palynomorphs
• Rare acritarchs
• One level contains
numerous
chitinozoans
• Some levels contain
large palynomorphs
related to algae, or
prasinophyceae?
• D3b (leiospheridia
bloom)
140 µm in diameter
Biostratigraphy
1. Verrucosisporites polygonalis
2. Dictyotriletes subgranifer
3
2
3. Camarozonotriletes sextantii
1
After Streel et al., 1987
1. Synorisporites papillensis
2. Knoxisporites riondae
AB or FD = early to
middle Emsian
?
After Streel et al., 1987
1. Rhabdosporites minutus
After Streel et al., 1987
1. Clivosispora verrucata
2. Dictyotriletes emsiensis
late FD or earliest AP
= late Emsian
After Streel et al., 1987
2. Grandispora protea
1. Acinosporites apiculatus
2
1
After Streel et al., 1987
1. Clivosispora verrucata
1
AP-Pro = latest Emsian
After Streel et al., 1987
4. Geminospora lemurata
3. Grandispora velata
4
3
2
1
2. Grandispora gabesensis
After Streel et al., 1987
1. Grandispora protea
Biostratigraphic results
Givetian
?
Eifelian
?
Emsian
?
Emsian
?
Pragian
Biostratigraphic results
?
?
7 - 8 meters
thick
?
?
D3b
Biostratigraphic results
?
?
D3b
?
?
Endemic species
Examples of new species
Examples of new species
Examples of new species
?
Cymbosporites n. sp.
Dictyotriletes n. sp.
A possible phylogeny?
A possible phylogeny?
A possible phylogeny?
A possible phylogeny?
A possible phylogeny?
A possible phylogeny?
A possible phylogeny?
FD-Min
Classe 4
FD-Pre Min
Classe 4
Y4
Classe 1
Classe 2
Classe 3
Classe 4
Classe 3
Classe 2
Classe 1
2
3
A possible
phylogeny?
1
4
Min
AB + FD pre Min
AB and FD
Monolete species
Previous records of the oldest
monolete species
• Arkhangelskaya 1985
- Devonomonoletes
microtuberculatus n. g. & n. sp
Limbomonoletes lenis n. g. & n. sp
- Russia - late Emsian.
• Kemp 1972
- Reticuloidosporites antarcticus n.
g. & n. sp.
- Antarctica – early Emsian
Palaeogeography
Palaeogeographic distribution of
miospores
Saudi Arabia
Palaeogeographic distribution of
K. riondae
Palaeogeographic distribution of
C. dammamensis
Palaeogeographic distribution of
miospores
Saudi Arabia
Conclusions
• The Jauf Formation is Emsian in age.
• The Emsian / Eifelian boundary is probably within the
lowest part of the Jubah Formation.
• The D3b event in north-western Saudi Arabia is precisely
placed in the west European Min interval Biozone (mid
Emsian).
• The assemblages contain monolete spores which are
among the oldest known with those from Antarctica.
• A possible phylogeny could be defined ranging from a
new Cymbosporites species to a new Dictyotriletes
species.
• Numerous new species have been observed. Some may
allow definition of a north-western Gondwanan
paleophytogeographic province.