Lithofacies and Palynostratigraphy of Some
Cretaceous and Paleocene Rocks, Surghar and Salt Range Coal Fields, Northern
Pakistan
By Peter D. Warwick, Shahid Javed, S. Tahir A.
Mashhadi, Tariq Shakoor, Asrar M. Khan, and A. Latif Khan
[Note: The following are excerpts from two unpublished
reports by Asrar M. Khan of the Hydrocarbon Development Institute of Pakistan.
These reports have been edited by Peter D. Warwick to reflect only palynological
results from the Surghar Range area. The original reports contained
palynological results from other northern Pakistan coal fields. The locations of
samples are given in text-table 1 and appendix I. The stratigraphic position of
samples with age dates are shown on text-figure 4]
By ASRAR M. KHAN
JUNE 1991
INTRODUCTION
Eight field samples (PW-90-1 to PW-90-8) from the Makarwal
area were received from Peter Warwick, USGS, for palynostratigraphy. Only two
samples, PW-90-1 and PW-90-3, yielded palynomorphs and age has been assigned,
whereas six samples (PW-90-2, PW-90-4 to PW-90-8) were barren of palynomorphs.
PALYNOSTRATIGRAPHY
Sample PW-90-1.--The sample yielded abundant organic matter
and a quantitatively and qualitatively rich microfloral assemblage. The
assemblage includes Inaperturopollenites spp., Zonalapollenites turbatus, Z.
trilobatus, Zonalapollenites spp. Ginkgocycadophytus nitidus, Gleicheniidites
senonicus, Deltoidospora juncta, Stereisporites antiquasporites, Trilobosporites
apiverrucatus, Contignisporites glebulentus, bisaccate pollen, Vitereisporites
sp., Podocarpidites sp., Cingutriletes clavus, Cycadopites sp.?,
Hymenozonotriletes sp., Cyathidites minor, C. crassingulatus, Leiotriletes sp.,
Lycopodiumsporites sp., Taurocusporites sp., Appendicisporites sp.,
Equisetosporites sp., Ephedripites sp., Concavissimisporites punctuates,
Cicatricosisporites hallei, and Appendicisporites sp.
Age.--The above assemblage indicates an Early Cretaceous age
for the sample.
Sample PW-90-2.--The sample yielded moderately rich black,
carbonized organic particles. The sample is barren of palynomorphs.
Age.--Cannot be assigned.
Sample PW-90-3.--The sample is abundantly rich in dark
organic matter and has yielded a rich palynoflora. The assemblage includes
Proxapertites operculatus, P. cursus, Spinizonocolpites bacculatus, S.
echinatus, Araucariacites sp., Echitriporites sp., Longapertites vaneendenburgi,
Verrutriletes sp., Echiperiporites sp., Tricolpites sp., Spinizonocolpites sp.,
Echitriporites trianguliformis, Ephedripites sp., Crassoretitriletes sp.,
Gemmatricolpites sp., Ischyosporites sp., Liliacidites sp., Psiladiporites sp.,
Polypodiisporites sp., Cyathidites australis, Retistephanocolpites williamsi,
Triorites minutipori, Dandotiasporites sp., Foveotricolpites perforatus,
Trisaccites sp., and Dyadosporites sp. (fungal).
Age.--The above assemblage indicates a Paleocene age for the
sample.
Sample PW-90-4.--The sample yielded a very low quantity of
organic matter. The sample is barren of palynomorphs.
Age.--Cannot be assigned.
Sample PW-90-5.--The sample yielded sporadic particles of
black organic matter. The sample is barren of palynomorphs.
Age.--Cannot be assigned.
Sample PW-90-6.--The sample yielded rich organic matter.
Single occurrence of Spinizonocolpites sp. and Triorites sp.
Age.--Cannot be assigned.
Sample PW-90-7.--The sample yielded a very low quantity of
organic matter. The sample is barren of palynomorphs.
Age.--Cannot be assigned.
Sample PW-90-8.--The sample yielded abundant dark-brown,
unstructured organic matter. The sample is barren of palynomorphs.
Age.--Cannot be assigned.
OBSERVATIONS
Sample PW-90-1 appears to be of the same horizon as sample
K-SH-5 or K-SH-1 of Early Cretaceous age, and sample PW-90-3 appears to be of
the same horizon as K-SH-2 of Paleocene age.
By ASRAR M. KHAN
MARCH 1990
INTRODUCTION
Of the 10 samples studied, 3 were barren of palynomorphs
(SH-MK-HT-2, K-SH-3, and K-SH-4). The remaining seven samples yielded reasonably
good mico-floral assemblage.
Sample SH-MK-HT-1.--The sample yielded abundant dark-colored
organic matter. Only a few miospores, such as Spinizonocolpites baculatus,
Spinizonocolpites echinatus, a monocolpote pollen, and a trilette spore were
recovered.
The Spinizonocolpites spp. may indicate a Paleocene age.
Sample SH-MK-HT-2.--The sample yielded rich dark-colored,
mostly unstructured organic matter. The sample is barren of palynomorphs.
Age cannot be assigned to this sample.
Sample K-SH-1.--The sample yielded moderately rich organic
matter and also a rich microflora. The assemblage includes Gleicheniidites
cercinidites, Cyathidities australis Liliacidites sp., Lygodiumsporites sp.,
Grinkgocycadophytus nitidus, Zonalapollenites dampieri, Deltoidospora sp.,
Microcachryidites antarcticus, Matonisporites crassingulatus Cycadopites sp.,
Inaperturopollenites sp., Classopollis classoides, Sphagnites clavus,
Phyllocladites sp., Cicatricosisporites australiensis, Cedripites sp.,
Vitreisporites pallidus, Pityosporites grandis, Zonalapollenites trilobatus, and
Cingulatisporites sp.
The above assemblage indicates a Late Jurassic to Early
Cretaceous age.
Sample K-SH-2.--The sample yielded abundant organic matter,
mostly unstructured. A rich microflora was recovered from the sediments. The
assemblage includes Lycpodiumsporites sp., Spinizonocolpites echinatus (short),
Triorites sp., (Myrica type) Retistephanocoliptes sp. Monoporate, Triporate
(annulate) pollen Spinizonocolpites echinatus (medium), Ephedrepites sp.,
Spinizonocolpites echinatus (long), Proxapertites sp., Longapertites sp.
(psilate), Concavisporites sp., Tricolpopollenites sp., Spinizonocolpites
baculatus, Lygodiumsporites sp., Echitricoliptes sp., and Triporites sp.
The above angiospermic palynomorph assemblage indicates a
Paleocene age for this sample.
Sample K-SH-3.--The sample yielded abundant unstructured,
carbonized organic matter. The sample is barren of palynomorphs.
Age cannot be determined.
Sample K-SH-4.--The sample yielded abundant unstructured,
carbonized organic matter. The sample is barren of palynomorphs.
Age cannot be determined.
Sample K-SH-5.--The sample yielded abundant organic matter
and was rich in microflora. The palynofloral assemblage includes
Appendicisporites problematicus, Matonisporites crassingulatus, Tricolpites
crassimurus, Cyathidites australis, Gleicheniidites cerciniditis, Podocarpidites
sp., Camarazonosporites sp., Araucariacites australis, Zonalapollenites
segmentatus, Baculatisporites truncatus, Z. trilobatus, bisaccate pollen,
Concavisporites infirmus, Microcachryidites antarcticus, Contignisporites
cooksoni, Cycadopites sp.?, Coupereisporites complexus, Vitreisporites sp.,
Rugubivesiculites sp., Lycopodiumsporites austroclavidites,
Cicatricosisporitespotomaensis, Z. acusus, Classopolis sp., Cedripites sp.,
Acanthotriletes levendensis, Cingulatisporites sp., Pityosporites grandis,
Ischyosporites sp., and Trilobosporites sp.
The above palynofloral assemblage is indicative of a Late
Jurassic to Early Cretaceous age.
Sample K-SH-6.--The sample yielded abundant dark-colored,
unstructured organic matter. Only a few palynomorphs, such as Retitricolpites
Foveosporites sp., Lygodiumporites sp., and Cupuliferoidaeopollenites sp., were
found.
An Early Cretaceous age is assigned to this sample on the
basis of Cupuliferoidaepollenites sp.
Sample T-SH-2.--The sample yielded abundant organic matter.
The palynofloral assemblage includes Classopollis classoides, Gleicheniidites
cercinidites, Cyathidites sp., bisaccate pollen, Biretisporites sp.,
Zonalapollenites segmentatus, Cyathidites australis, Eucomiidites sp.,
Distalangulisporites perplexus, Concavisporites juriensis, Deltoidospora
psilostoma, and Cancavisporite sp.
The above palynomorph assemblage is indicative of an Early
Cretaceous age. The absence of any angiospermic pollen also suggests an Early
Cretaceous age for this sample.
Sample T-SH-3.--The sample yielded abundant organic matter.
The microfloral assemblage includes Classopollis classoides, Cyathidites sp.,
Zonalapollenites dampieri, Inaperturopollenites spp., Appendicisporites
bilateralis, Entylissa sp., Ischyosporites sp., Densoisporites sp.,
Podocarpidites sp., Cyathidites australis, Sphagnites sp., Cingulatisporites
sp., and Ginkgocycadophytus sp. A few dinoflagellates, such as Gonyaulacysta sp.
and Balisphearidium sp., were also encountered.
The above palynofloral assemblage indicates an Early
Cretaceous age for this sample.
CONCLUSIONS
Ten grab samples were palynologically studied. Three samples
(SH-MK-HT-2, K-SH-3, and K-SH-4) were barren of palynomorphs. Therefore, age
cannot be assigned to these samples.
Two samples, SH-MK-HT-1 and K-SH-2, are of Paleocene age.
The remaining five samples (K-SH-1, K-SH-5, K-SH-6, T-SH-2,
and T-SH-3) are of Late Jurassic to Early Cretaceous age. Late Jurassic and
Early Cretaceous ages can be differentiated if sampling is performed in a
continuous sequence.
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