Finding the right pollen to find the oil
The role of palynology
in the onshore exploration
programme of Suriname
uGEO 059-05-2009
In Suriname, palynology plays an important role in
hydrocarbon exploration. In onshore prospecting,
large-scale palynological analyses are carried out. The
paleoenvironmental information derived from palynology is
combined with detailed log response and sedimentological
analyses. The combined data serve as input for the 3D
paleogeographic maps that are the starting point for the
further development of the field. In addition, the maps
have powerful predictive value for locating ‘sweet spots’ in
the immediate vicinity of the field.
Figure 1Location of the Tambaredjo and Calcutta oil fields near Paramaribo, the capital of Suriname.
The Suriname-Guyana basin holds high
promise of hydrocarbons. This passivemargin basin has a thick, predominantly
clastic sedimentary cover and contains a firstclass source rock, the Cenomanian-Turonian
Canje Formation. The expectations for the
near future are high, with major seismic
programmes being executed and many
exploration wells being spudded or planned.
Yet, despite decades of exploration activity
in the area, the only hydrocarbon reserves
to be found so far are the onshore Calcutta
and Tambaredjo oil fields in Suriname (Fig.
1). Combined, the proven reserves of these
fields exceed more than one billion barrels
of oil. The oil in these fields is trapped
stratigraphically in coastal reservoir sands at
relatively shallow depths, but oil exploration
in the onshore area is more complicated than
it seems. While oil shows are quite common
in wildcats, finding and developing new
fields is more of a challenge. Recently, the
state-owned Staatsolie company developed
a play concept for the onshore called the
“Palaeocene-Eocene Fairway”.
Proxapertites cursus
Foveotriletes margaritae
Estuary
Bombacacidites annae
Lagoon
Potential Reservoirs!
Mudflat
Tidal Inlet
Apectodinium sp.
Figure 2 3D representation of the Paleocene-Eocene paleogeography of the Suriname-Guyana Basin margin. Clays predominate in the tidal flats (indicated in brown-grey), the estuarine and shallow marine environments are dominated by sands (indicated in yellow).
For each environment, characteristic palynomorphs are displayed.
Psilatricolporites crassus
Adnatosphaeridium multispinosum
Mudflat
No Seal!
In this play concept, palynology fulfils
an important role. In brief, the concept
predicts that hydrocarbon accumulations
are restricted to those areas where clay is
sufficiently represented in the sedimentary
column. Typically, these clays are found
within tidal flat settings, away from major
river systems (Fig. 2). The play concept
assumes that the palaeo-valleys of the
major river systems from the Palaeocene
and Eocene ran from South to North and
were situated at the same locations as the
present-day large rivers. This is supported
by the sandy nature and lack of seal in
wells drilled near the Nickerie and Corantijn
rivers. In between these rivers, mud flats
with tidal inlet complexes are expected.
These mud flats stretch out in a narrow
belt parallel to the palaeo coastline (Fig.
3). When studied in detail, the belt can be
subdivided in separate patches (Fig. 4), each
of which is represented by an intricate 3D
network of sands and clays. Once a patch has
been acknowledged as a prospect, detailed
sediment-petrographical and palynological
studies are carried out. Log responses are
used to establish high-resolution correlations
between the closely spaced wells and
palynology is then used to map, both in time
and space, the outline and distribution of the
various palaeoenvironments.
Figure 3 Cross section of the onshore basin margin against the stratigraphy. The prospective mud flats are restricted to the narrow belt between the red lines. Sand is indicated in yellow, clay in black
and oil is indicated in green.
Geo Energy and Geo Information
TNO Built Environment and Geosciences
Geological Survey of the Netherlands is the
central geoscience centre in the Netherlands
for information and research to promote the
sustainable management and use of the subsurface and its natural resources.
TNO Built Environment and Geosciences
Geological Survey of the Netherlands
Princetonlaan 6
PO Box 80015
3508 TA Utrecht
The Netherlands
Figure 4 Play map of the Paleocene – Eocene Fairway, developed by the state-owned Staatsolie Maatschappij Suriname NV. Prospective areas are indicated in green, sand-prone areas in yellow
and the producing Tambaredjo and Calcutta oil fields in purple. The dotted line represents the
Suriname-Guyana Basin margin.
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