Download The Agulhas – Karoo Geoscience Transect: from a sheared margin

2.2 Subproject
94
Sub-Project 2.2
Agulhas-Karoo Geoscience Transect: A land-sea deep crustal seismic, MT
and petrological transect across the Agulhas Plateau, the Agulhas Fracture
Zone, the Agulhas Bank, the Cape Fold Belt and into the Karoo Province
Participants
* Coordinators
Institutions
Names
Email addresses
Alfred Wegener Institute
(AWI)
K. Gohl*
G.Uenzelmann-Neben
[email protected]
[email protected]
GeoForschungs-Zentrum
Potsdam
(GFZ)
O. Ritter*
U. Weckmann
M. Weber
A. Schulze
T. Ryberg
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
University of Cape Town
(UCT)
H.E. Frimmel*
G. Viola
A.P. le Roex
Z. Ben-Avraham
M.J. de Wit
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
Council for Geoscience
E. Stettler
C. de Beer
[email protected]
[email protected]
Univ. Witwatersrand
S. Webb
[email protected]
Univ. Port Elizabeth
R. Shone
P. Booth
[email protected]
[email protected]
Univ. Natal
M. Watkeys
[email protected]
Univ. Stellenbosch
R. Scheepers
[email protected]
Petroleum Agency of SA
I. McLachlan
[email protected]
Fugro Airborne Surveys
L. Ameglio
[email protected]
Green’s Geophysics
R. Green
-
Requested Funding
Total for the 5-year duration project beginning in 2004: Euros 2381300
AWI
GFZ
RSA
Totals
2004
0
101000
62600
163600
2005
461600
618000
131400
1211000
2006
74600
418000
99600
592200
2007
72600
168000
45800
286400
2008
72600
40500
15000
128100
2.2 Subproject
95
Summary
Southern Africa and its southern continental margin offer an
unrivalled region, where continental accretion processes over a
period of more than 3.5 billion years can be studied. Along a
geoscientific transect, stretching from the offshore Agulhas Plateau
across the Agulhas Fracture and the Outeniqua Basin, continuing
across the Cape Fold Belt, the Namaqua-Natal Belt and into the
Karoo Province and the southern Kaapvaal Craton, geophysical and
geological/ geochemical data and samples will be collected in order
to build a model of the evolution and crustal accretion as well as the
continental break-up of this region. With such a single transect,
multifold significant objectives can be addressed such as the
Mesoproterozoic accretion processes along the southern margin of
the Kaapvaal Craton, the extent of Pan-African inliers in the Cape
Fold Belt, the extent and formation of the Cape Fold Belt, the sources
for the Beattie Magnetic Anomaly and the Southern Cape
Conductivity Belt, the continental/ oceanic origin of the Agulhas
Plateau, the formation of the Agulhas Fracture Zone and its
consequences for basin formation and uplift processes relevant for
the hydrocarbon producing provinces of the Outeniqua Basin. A
combined land-sea deep crustal seismic reflection and refraction
survey as well as a magnetotelluric survey along the transect will
provide detailed structures and constraints for physical parameters
from the upper crust to the upper mantle which will be integrated
with geological, petrological and geochemical analysis on rock
composition, age and alteration history to form an overarching
geodynamic model for the evolution of the region and its tectonic
units.
2.2 Subproject
96
Scientific Background
Continents are known to be made up of a collage of displaced terranes of various origins that
accumulate or accrete when continental margins are active. Today, oceanic plateaux, which
can be extinct island arcs, extinct spreading ridges, seamounts, or disrupted fragments of
continental crust, are passive features that are embedded within the oceanic lithosphere. When
large enough, they resist subduction, do not return to the mantle but accrete to existing
continents. A prime example of such an oceanic plateau is the Agulhas Plateau situated
offshore southern Africa. It can be expected that this plateau will collide with the present
African continent when the southern African margin becomes active again.
Southern Africa offers an unrivalled region, where continental accretion processes over a
period of more than 3.5 billion years can be studied: A composite Archean (>2.5 Ga) craton
(Kaapvaal Craton) is flanked by progressively younger crust (Fig. 2.2.1), recording four main
stages of continental lithosphere formation: 2.06 - 1.80 Ga (Eburnian) Kheis Belt, 1.2 - 1.0
(Grenvillian) Namaqua Natal Belt, 0.58 - 0.48 (Pan-African) Saldania Belt, and the 0.25
(Gondwanide) Cape Fold Belt. Large areas of the Namaqua-Natal Belt are covered by
Mesozoic Karoo sediments, and most of the Saldania Belt is overlain by rocks of the younger
Cape Fold Belt. Only a few exposures in form of basins such as the Kangoo and the Kaaimans
Inlier can provide reliable data on tectonism which are vital for the understanding of accretion
and collision in southern South Africa.
The eastern margin of the craton has been reworked by Mesozoic Gondwana tectonic
processes. This left a sharp break, manifest at the surface by the Lebombo monocline (a
priority target of Subproject 2.3, see below). The best region to study the successive
accretions of continental lithosphere onto the Kaapvaal Craton since its stabilisation around
2.0 Ga is its southern margin. The proposed geophysical (seismic and magnetotelluric)
transect cuts across all of the above <2.0 Ga tectonic belts and thus also at least three major
continental suture zones of vastly different age. The same area also hosts two of Earth’s
largest known geophysical anomalies, the Beattie Magnetic Anomaly (BMA) and the
Southern Cape Conductive Belt (SCCB). Both anomalies extend for almost 1000 km in eastwest direction across the whole of southern South Africa (Fig. 2.2.2). The surface expressions
of these anomalies seem to coincide with the mapped boundaries of the Cape Fold Belt and
the Namaqua Natal Belt. The nature of both geophysical anomalies remains enigmatic; they
have been interpreted as a slice of paleo-oceanic lithosphere or alternatively as thrust zones,
but neither their relative age nor their extent to depth and internal structure are known. A
better understanding of their geometry and origin is essential for any meaningful
reconstruction of the subsequent break-up processes.
By extending the transect offshore to the Agulhas Plateau (Fig. 2.2.3), not only can the
question of continent formation, but also that of the demise of continents be addressed. Late
Mesozoic basins, both onshore and offshore, formed subsequent to Gondwana break-up.
Today they are important exploration targets for the petroleum industry. The nature and origin
of the Agulhas Plateau are poorly known and this project promises to provide major new
insights into this oceanic plateau. Finally, the southern tip of South Africa, though surrounded
by passive continental margins, displays a considerable relief. This gives rise not only to
spectacular landscapes, but also to the recognition that southernmost Africa is affected by
active neotectonic activity. Both causes and hazards as well as the utilization potential of this
neotectonic activity are not fully understood. The proposed project, in conjunction with the
other Working Groups, offers an opportunity to address these issues.
2.2 Subproject
97
Figure 2.2.1. Distribution of tectonic units around the Archaean Kaapvaal Craton in southern Africa. Large parts of the
Namaqua Natal Belt and the southern segment of the Kaapvaal Craton are covered with Karoo sediments.
Fig. 2.2.2. The Beattie Magnetic Anomaly (red and magenta colours and white dots) and the Southern Cape Conductive
Belt (SCCB, black and white dashed lines) are continental scale geophysical anomalies. They stretch from east to west
for more than 1000 km across the whole of southern South Africa (after Harvey et al., 2001).
2.2 Subproject
98
Fig. 2.2.3. (Top) Proposed offshore seismic transects across the Agulhas Plateau and the southern margin of the African
plate. (Bottom) Proposed geophysical transects across the SCCB and the BMA. (Yellow: onshore/offshore seismic
experiment, blue: near vertical reflection seismic, red: magnetotelluric profiles)
2.2 Subproject
99
Key references
Allen, R.B., Tucholke, B.E. (1981). Petrography and implications of continental rocks from the
Agulhas Plateau, southwest Indian Ocean. Geology, 9, 463-468.
Bauer, K., Schulze, A., Ryberg, T., Sobolev, S. V. and Weber, M. (2003): Classification of lithology
from seismic tomography. A case study from the Messum igneous complex, Namibia. Journ.
Geophys. Res., 108(B3), 2152, doi: 10.1029/2001JB001073 .
Ben-Avraham, Z., Hartnady, C.J.H., Malan, J.A. (1993) Early tectonic extension between the Agulhas
Bank and the Falkland Plateau due to the rotation of the Lafonia microplate. Earth Planet. Sci.
Lett. 117, 43-58.
Ben-Avraham, Z., Hartnady, C.J.H., le Roex, A.P. (1995) Neotectonic activity on continental
fragments in the southwest Indian Ocean: Agulhas Plateau and Mozambique Ridge. J. Geophys.
Res., 100, 6199-6211.
Ben-Avraham, Z. (1995) Neotectonic activity offshore southeast Africa and its implications, S. Afr. J.
Geol., 98, 202-207.
Ben-Avraham, Z., Hartnady, C.J.H., Kitchin, K.A. (1997) Tectonics of the Agulhas-Falkland
transform. Tectonophys.,282, 83-98.
Frimmel, H.E., Hartnady, C.J.H., Koller, F. (1996) Geochemistry and tectonic setting of magmatic
units in the Pan-African Gariep Belt, Namibia. Chem. Geol., 130, 101-121.
Frimmel, H.E., Frank, W. (1998) Neoproterozoic tectono-thermal evolution of the Gariep Belt and its
basement, Namibia/South Africa. Precambr. Res., 90, 1-28.
Frimmel, H.E., Fölling, P.G., Diamond, R. (2001) Metamorphism of the Permo-Triassic Cape Fold
Belt and its basement, South Africa. Mineral. Petrol., 73, 325-346.
Frimmel, H.E., Fölling, P.G., Eriksson, P. (2002) Neoproterozoic tectonic and climatic evolution
recorded in the Gariep Belt, Namibia and South Africa. Basin Research, 14, 55-67.
Frimmel, H.E. (in press a) Neoproterozoic sedimentation rates and timing of glaciations - a southern
African perspective. - In: Condie, K C, Veenstra, F (eds.) Tempos and Events in Precambrian
Time, Elsevier (Amsterdam).
Frimmel, H.E. (in press b) Formation of a late Mesoproterozoic supercontinent: The South Africa East Antarctica connection. In: Condie, K.C., Veenstra, F. (eds.) Tempos and Events in
Precambrian Time, Elsevier (Amsterdam).
Gohl, K. & Uenzelmann-Neben, G. (2001). The crustal role of the Agulhas Plateau, southwest Indian
Ocean: evidence from seismic profiling. Geophys. J. Int., 144, 632-646.
Hartnady, C.J.H., Ben-Avraham, Z., Rogers, J. (1992) Deep-ocean basins and submarine rises off the
continental margin of southeastern Africa: new geological research developments. South African
J. Sci., 88, 534-539.
Harvey, J.D., de Wit, M.J., Stankiewicz, J., and Doucouré, M. (2001). Structural variations of the
crust in the southwestern Cape derived from seismic receiver functions. S A Journal Geology,
104, 231-242.
Lyakhovsky, V., Ben-Avraham, Z., Reznikov, M. (1994) Stress distribution over the Mozambique
Ridge. Tectonophys., 240, 21-27.
McMillan, I.K., Brink, G.J., Broad, D.S. & Maier, J.J. (1997). Late Mesozoic sedimentary basins off
the south coast of South Afrika. In: Selley, R.C. (Ed.), Sedimentary Basins of the World: The
African Basins. Elsevier, Amsterdam, 319-376.
Niemi, T.M., Ben-Avraham, Z., Hartnady, C.J.H. (2000) Post-Eocene seismic stratigraphy of the deep
ocean basin adjacent to the southeast African continental margin: a record of geostrophic bottomcurrent systems. Marine Geology, 162, 237-258.
Raith, J.G., Cornell, D.H., Frimmel, H.E., de Beer, C.H. (2003) New insights into the geology of the
Namaqua Tectonic Province, South Africa, from ion microprobe dating of detrital and
metamorphic zircon. J. Geol., in press.
Ritter, O., Weckmann, U., Vietor, T. and Haak, V. (2003) A magnetotelluric study of the Damara Belt
in Namibia 1. Regional scale conductivity anomalies, Phys. Earth Planet. Inter., 138:71-90, 2003,
doi:10.1016/S0031-9201(03)00078-5
Ritter, O., Ryberg, T., Weckmann, U., Hoffmann-Rothe, A., Abueladas, A., and Garfunkel, Z., (2003)
Geophysical images of the Dead Sea Transform in Jordan reveal an impermeable barrier for fluid
flow, Geophys. Res. Lett., 30(14):1741-1744, 2003, doi:10.1029/2003GL017541
2.2 Subproject
100
Tucholke, B.E., Houtz, R.E., Barrett, D.M. (1981). Continental crust beneath the Agulhas Plateau,
southwest Indian Ocean. Journal of Geophysical Research, 86, 3791-38061.
Uenzelmann-Neben, G., Gohl, K., Ehrhardt, A. & Seargent, M.J. (1999). Agulhas Plateau, SW Indian
Ocean: New evidence for excessive volcanism. Geophys. Res. Lett., 26, 1941-1944.
Uenzelmann-Neben, G. (2001). Seismic characteristics of sediment drifts: An example from the
Agulhas Plateau, southwest Indian Ocean. Marine Geophysical Researches, 22, 323-343 .
Uenzelmann-Neben, G. (2003). Contourites on the Agulhas Plateau, SW Indian Ocean: Indications for
the evolutions of currents since Paleogene times. In: Stow, D., Pudsey, C., Howe, J., Faugeres,
J.C., Viana, A.R. (eds), Deep-water contourite systems: Modern drifts and ancient series.
Geological Society of London, Memoir, 22, 271-288.
Weckmann, U., Ritter, O. and Haak, V. (2003) A magnetotelluric study of the Damara Belt in
Namibia 1. MT phases over 90° reveal the internal structure of the Waterberg Fault/Omaruru
Lineament, Phys. Earth Planet. Inter., 138:91-112, 2003, doi:10.1016-S0031-9201(03)00079-7
Key questions arising are:















Does the Mesoproterozoic crust continue from the Namaqua Belt in the west to the Natal
Belt in the east? If yes, what is the geometry of this belt along the southern flank of the
Kaapvaal Craton?
How much and what type of Neoprotererozoic crust exists to the south of the Kaapvaal
Craton?
Are some (and if yes, which) of the Pan-African inliers in the Cape Fold Belt synorogenic intramontane molasse basins?
What is the Pan-African kinematic history of these inliers and how does it relate to that of
the Gariep Belt and the Ross Orogen?
What is the subsurface geometry of major tectonic and stratigraphic boundaries within the
Cape Fold Belt; how do the features mapped on the surface continue to depth?
To what extent can the Cape Fold Belt be followed off-shore to the south?
Do the Beattie magnetic anomaly and the Southern Cape Conductivity Belt (SCCB) have
the same source?
Can we resolve structural details within the SCCB and its depth extent?
Is the SCCB caused by partially serpentinized rocks or is it connected with tectonic
processes of the orogenic front (Cape Fold Belt)?
Is the Agulhas Plateau oceanic or continental?
What is the age and the source of the volcanics of the Agulhas Plateau and how can the
magmatic volume added to the Agulhas Plateau and its surroundings be quantified?
Under what geodynamic process did the sheared margin of South Africa evolve?
What is the origin of the Agulhas Fracture Zone?
Has any magmatism been associated with break-up along the Agulhas Fracture Zone, and
has the Fracture Zone been reactivated through present times?
How did the Outeniqua Basin form and what is the nature of the underlying basement and
deep crust?
Objectives
Ten main objectives to be addressed within a number of sub-projects are briefly explained
below in a sequence that reflects the progressively younger ages of geological phenomena of
interest:
2.2 Subproject
101

Nature of the basement to the Karoo Supergroup rocks and the extent to which it fits into
a postulated contiguous Namaqua-Natal Belt: The new geophysical data are expected to
provide new insights into the geometry of the main Mesoproterozoic crustal structures and
thus yield crucial information for the modelling of Mesoproterozoic accretion processes
along the southern margin of the Kaapvaal Craton.

A combination of petrological, structural and geochemical studies, combined with the
geophysical data, are aimed at assigning the various tectono-stratigraphic units of the
Saldania Belt (Fig. 2.2.4) to the different stages of Pan-African basin development and to
place them into a regional, intercontinental framework of Gondwana assembly.
Particularly their relationship to other Pan-African units along the western margin of
southern Africa (Gariep, Damara, Kaoko Belt and equivalents in South America) and the
Ross Orogen in Antarctica will be tested.

The expected geophysical data will be supplemented by systematic ground gravimetric
measurements on the George Pluton and surrounding rocks in order to delineate the shape
of the pluton at depth, calculated by gravity data inversion, and also its spatial
relationships with the surrounding rocks.

The accretion process that gave rise to the Cape Fold Belt remains enigmatic, as no highgrade metamorphic core complexes or syn-orogenic igneous activity are known. The new
geophysical data, combined with extensive structural and stratigraphic studies, will serve
as basis on which to establish the geometry of major tectonic features by tracing tectonic
and stratigraphic boundaries from surface outcrops into depth through the crust.

The up to 200 km wide SCCB was mapped in the late 1960s by means of magnetometerarray studies with stations separated by tens to hundreds of kilometers. A common source
for the BMA and the SCCB has been proposed by several authors but remains uncertain
because direct observations are missing. Preliminary seismic work across the BMA
indicates zones of high reflectivity in the upper crust, while receiver functions studies
identify sharp crustal discontinuities at depths of 8 and 18 km which are interpreted as a
10km thick block of altered Mesoproterozoic mafic-ultramafic rocks. However, this is by
no means the only possible interpretation and we note that in some cases, low-resolution
geophysical data sets are more a hindrance than a help for geodynamic understanding. For
example the interpretation of the SCCB, as a serpentinized slice of paleo-oceanic crust is
doubtful in view of recent magnetotelluric investigations with a much higher resolution
from the Damara Mobile Belt in Namibia (Ritter et al., 2003). This new data set resolves
the internal structure of a comparable high conductivity belt and shows clearly that
conductive zones correlate with deep reaching fossil shear zones.

Thermo-mechanical forward modelling of the terrane accretion/ continental collision will
investigate the geodynamic significance of the BMA and SCCB geophysical anomalies.
One process we wish to model is the progressive magnetisation of crustal rocks as they
pass the Curie isotherm during syntectonic and posttectonic exhumation. Additionally, the
distribution of strain within the models will shed light on the distribution of the shear
zones and their final geometry in the eroded orogen. The results will be applicable to
collisional settings in general.

The extensional history of the Cape Fold Belt related to the break-up of Gondwana during
the Mesozoic will form part of the study, where normal faults and related structures can be
identified along the planned transect through the Cape Fold Belt.
2.2 Subproject
102

The nature of the Agulhas Plateau (oceanic versus continental) and the amount of
magmatic material added to it at various times is a premier target of the offshore studies.
Recent deep seismic surveying of the southern central Agulhas Plateau indicates very high
P-wave velocities (>7 km/s) in the lower two-thirds of the 25 km thick crustal column,
suggesting an oceanic crustal affinity. However, this is in conflict with the interpreted
continental origin of quartzo-feldspathic samples dredged from the plateau. It is uncertain
if the observed velocity-depth distribution is symptomatic for the entire plateau or if
continental crustal fragments are embedded in the plateau. An important aim is to
understand the role of young volcanism near the northern Agulhas Plateau.

Origin of the Agulhas Fracture Zone and its relationship to the separation of the Falkland
Plateau. Furthermore, the question of any magmatism having been associated with breakup and the tectonic as well as magmatic consequences of possible repeated re-activation of
the fracture zone along the continental margin will be addressed.

On the Outeniqua Basin of the Agulhas Bank, the nature and position of the crust-mantle
boundary will be examined, as well as the development of the oil-producing sedimentary
basin and its deep-seated fractures during break-up.
C
dt
e
an
err
e
ran
ter
rg
nd
rbe e
ge an
Ty terr
33 S
l an
Bo
la
art
Sw
o
A
P
E
Mid-Palaeozoic to Cenozoic cover
Gamtoos Group
Cape Granite Suite
Klipheuwel Group
Kaaimans Group
Kansa Subgroup
Kango
Goegamma Subgroup Group
Boland Subgroup
Malmesbury
Tygerberg Subgroup
Group
Swartland Subgroup
Kango inlier
Worcester
FOL
D
Gamtoos
inlier
Oudtshoorn
BELT
Cape Town
34oS
Port
Elizabeth
Kaaimans inlier
Atlantic
Ocean
o
18 E
N
Indian Ocean
o
20 E
22oE
o
24 E
Fig. 2.2.4. Distribution of Pan-African units within the Cape Fold Belt.
Methodologic approach and techniques
Seismic onshore/offshore experiments
Two offshore multichannel reflection and refraction/wide-angle seismic profiles will be
conducted (see Fig. 2.2.3). While both profiles cross the sheared margin of the Agulhas
Fracture Zone, one profile is primarily aimed for imaging the deep structure of the Agulhas
Plateau, and the other profile targets the Outeniqua Basin and the transition to the Cape Fold
Belt. The latter profile will be supplemented by a simultaneous onshore wide-angle seismic
line (WRR) which extends for approximately 300 km into the Cape Fold Belt. From the
2.2 Subproject
103
combined experiment we intend to resolve structural details of the Agulhas Fault Zone and
the velocity structure of the ocean continent transition. This marine part of the project will be
conducted in cooperation with Working Group 3, Sub-Project “Neogene evolution of the
southern African margin related to tectonism, ocean currents and changes in sea-level”. A
proposal (AISTEK-I) for shiptime on RV Sonne was submitted to PTJ-BMBF (Germany).
The positive review resulted in a recommendation that this project be included in the next RV
Sonne cruise schedule.
Combined near vertical reflection (NVR) seismic and magnetotelluric (MT)
experiments.
Two combined high resolution seismic and MT experiments (MT1, MT2 and NVR1 and
NVR2) are planned to resolve the crustal constitution of the Cape Fold and Namaqua-Natal
mobile belts. The first profile coincides with the onshore part of the onshore/offshore line
from the coast across the Cape Fold Belt. This profile will be continued northwards in a
second field experiment. Focus of this experiment will be the deep structures of the NamaquaNatal Mobile belt and particularly the Beattie Magnetic Anomaly. The combined length of
these onshore profiles is approximately 300 km. They cross major accretionary complexes
and the above mentioned continental scale geophysical anomalies (see Fig. 2.2.2). Along this
profile we plan to extend the already successfully tested method of so-called petrotomography (Bauer et al., 2003) to greater depths. This gives a unique opportunity to map the
subsurface distribution of petrological units to depths as much as approx. 10 km.
The electrical image of the Namaqua-Natal Belt to Kaapvaal Craton transition
Most of the Namaqua-Natal Mobile Belt and particularly its northern boundary into the
Kaapvaal Craton are obscured by the Karoo sedimentary cover (see Fig. 2.2.1).
Magnetotelluric measurements can potentially identify large scale paleo-shear zones and may
be able to resolve the craton boundary at depth. Acquiring seismic and magnetotelluric data
along coincident profiles is an excellent opportunity to utilize the combined imaging power of
the two methods. The coverage of the craton boundary will require a continuation the
magnetotelluric profiles mentioned above in a northeastern direction for approximately 200
km.
Geochemical/geochronological studies
Provenance and geochronological studies of surface samples from the Pan-African inliers
within the Cape Fold Belt for establishing their stratigraphic position within the regional
framework of Pan-African belts. Collecting (dredging) samples from outcropped basement of
several sites of the Agulhas Plateau will provide data on the composition and age of the
volcanics as well as potential continental rocks. The geochemical analysis will be integrated
with the geophysical data for build a consistent evolutionary model.
Structural Geology
Structural geological studies to delineate the lateral distribution of stratigraphic and tectonic
units within the Cape Fold Belt.
2.2 Subproject
104
Drilling of the Agulhas Plateau and the Beattie Magnetic Anomaly
In addition to dredging rock samples off the sea-floor, drilling into the basement at several
sites of the Agulhas Plateau would provide invaluable information about the origin and
evolutionary process of the plateau’s crust. Participation in the IODP proposal ISOLAT with
a site on the plateau or even a separate drill proposal is aimed for within this project.
Continental deep drilling of the Beattie magnetic anomaly, accompanied with intensive
geophysical, petrological and geochemical analyses may be the only way to really understand
(in situ) the true nature of this major anomaly.
Thermo-mechanical numerical modelling of continental collision
Forward models of collisional settings simulate the progressive magnetisation of crustal rocks
while they pass the Curie isotherm during syn-tectonic and post-tectonic exhumation.
Modelling strain distribution will shed light on the distribution and geometry of shear zones in
the eroded orogen.
Logistic/equipment requirements






Access to a suitable research vessel for conducting new seismic reflection and refraction
lines and petrological sampling (RV Sonne approval for seismic work is pending);
Access to existing seismic lines of Agulhas Bank (Petroleum Agency of SA);
Access to existing seismic lines across the Cape Fold Belt and southern Natal Belt
(Council for Geoscience);
Access to gravity and magnetic data acquisition equipment;
Drilling facilities (on- and offshore);
Access to analytical facilities for petrological, geochemical and geochronological studies
(EMPA, SHRIMP or equivalent single mineral grain dating facility, XRF, ICP-MS).
Expected outcomes/deliverables





Better understanding of the nature and significance of lithospheric structures in
continental break-up processes.
Documentation of the crustal architecture of southern Africa and its continental margins;
Improved understanding of the relation of geophysical anomalies to geodynamics of
accretion/collision
Significant improvement in the understanding and quantification of asthenospherelithosphere mass transfer;
Reconstruction of Mesozoic paleo-geography;
2.2 Subproject
105
Estimated Funding Requirements
Manpower:
(all salaries are based on the German public service scale (BAT))
1 post-doc for marine deep crustal seismic data
geodynamic modelling
Administrative:
AWI
Salary group: BAT IIa (€ 4800/month)
Duration:
01/2005 – 12/2005
01/2006 – 12/2006
01/2007 – 12/2007
01/2008 – 12/2008
processing, modelling and interpretation;
€
€
€
€
57,600
57,600
57,600
57,600
subtotal:
€ 230,400
1 post-doc for wide-angle reflection/refraction seismic (WRR) data processing, modelling and
interpretation; lithospheric evolution of southern African continent
Administrative:
GFZ
Salary group: BAT IIa-O (€ 4250/month)
Duration:
01/2005 – 12/2005 € 51,000
01/2006 – 12/2006 € 51,000
01/2007 – 12/2007 € 51,000
subtotal:
€ 204,000
1 PhD student for near vertical reflection seismic (NVR) data processing, modelling and
interpretation; lithospheric evolution of southern African continent
Administrative:
GFZ
Salary group: BAT IIa-O/2 (€ 2125/month)
Duration:
01/2005 – 12/2005 € 25,500
01/2006 – 12/2006 € 25,500
01/2007 – 12/2007 € 25,500
subtotal: € 76,500
1 post-doc for magnetotelluric surveys MT1, MT2 and MT3; experiment coordination; data
acquisition, processing, modelling
Administrative:
GFZ
Salary group: BAT IIa-O (€ 4250/month)
Duration:
07/2004 – 12/2004 € 25,500
01/2005 – 12/2005 € 51,000
01/2006 – 12/2006 € 51,000
01/2007 – 12/2007 € 51,000
01/2008 – 06/2008 € 25,500
subtotal: € 204,000
1 PhD student for magnetotelluric survey MT1 and MT2; integrated modelling of MT and
seismic NVR data
Administrative:
GFZ
Salary group: BAT IIa-O/2 (€ 2125/month)
2.2 Subproject
Duration:
106
01/2004 – 12/2004
01/2005 – 12/2005
01/2006 – 12/2006
€ 25,500
€ 25,500
€ 25,500
subtotal:
€ 76,500
subtotal:
€ 86,400
1 PhD student for sediment provenance/stratigraphic studies
Administrative:
RSA
Salary group: BAT IIa/2 (€ 2400/month)
Duration:
01/2004 – 12/2004 € 28,800
01/2005 – 12/2005 € 28,800
01/2006 – 12/2006 € 28,800
1 PhD student for petrology/geochemistry of Agulhas Plateau samples
Administrative:
RSA
Salary group: BAT IIa/2 (€ 2400/month)
Duration:
01/2005 – 12/2005 € 28,800
01/2006 – 12/2006 € 28,800
01/2007 – 12/2007 € 28,800
subtotal:
€ 86,400
3 MSc students for structural geological work in the Cape Fold Belt
Administrative:
RSA
Salary group: 3 x € 1200/month
Duration:
01/2004 – 12/2004 € 14,400
01/2005 – 12/2005 € 14,400
subtotal:
€ 28,800
1 MSc student for ground gravimetric study of George Pluton
Administrative:
RSA
Salary group: € 1200/month
Duration:
01/2004 – 12/2004 € 14,400
01/2005 – 12/2005 € 14,400
subtotal:
total staff:
€ 28,800
=========
€1,021,800
Field work (excluding ship costs):
Magnetotelluric surveys MT1, MT2 and MT3 (3 x 100 km profile)
Administrative:
GFZ
Duration:
02/2004 – 04/2004 € 50,000
02/2005 – 04/2005 € 50,000
02/2006 – 04/2006 € 50,000
subtotal:
€ 150,000
subtotal:
€ 380,000
Marine seismic survey (instrument operating/rental costs, freight,
consumables)
Administrative:
AWI
Duration:
02/2005 – 03/2005 € 380,000
2.2 Subproject
107
WRR seismic survey (300 km profile)
Administrative:
GFZ
Duration:
02/2005 – 03/2005
€ 200,000
subtotal:
€ 200,000
subtotal:
€ 400,000
subtotal:
€ 50,000
subtotal:
€ 10,000
NVR1 and NVR2 seismic surveys (2 x 100 km profile)
Administrative:
GFZ
Duration:
03/2005 – 04/2005 € 200,000
03/2006 – 04/2006 € 200,000
Petrological, geochemical and geo-chronological studies
Administrative:
RSA
Duration:
01/2005 – 12/2005 € 25,000
01/2006 – 12/2006 € 25,000
Structural geology studies
Administrative:
Duration:
RSA
07/2004 – 12/2004
01/2005 – 06/2005
€
€
5,000
5,000
total field work:
=========
€ 1,190,000
Travel expenses:
a) Congresses and workshops:
Participation of project scientists at scientific congresses
Basis: 1 international (2000 €), 1 national (1000 €) per year for 5 scientists
Administrative:
GFZ
Time frame:
2005-2008
€
subtotal:
€
60,000
60,000
Participation of project scientists at scientific congresses
Basis: 1 international (2000 €), 1 national (1000 €) per year for 5 scientists
Administrative:
AWI
Time frame:
2005-2008
€
subtotal:
€
60,000
60,000
Participation of project scientists at scientific congresses
Basis: 1 international (2000 €), 1 national (1000 €) per year for 5 scientists
Administrative:
RSA
Time frame:
2005-2008
€
subtotal:
€
60,000
60,000
Annual project workshops, alternately in Germany and South Africa
Basis: 10 participating scientists, 1 week duration
Time frame:
2004-2008
subtotal:
€ 100,000
€ 100,000
2.2 Subproject
108
b) Training courses for South African students:
Seismic training of one South African student at AWI (4 months)
Administrative:
AWI
Time frame:
2005
subtotal:
Seismic/MT training of one South African student at GFZ (4 months)
Administrative:
GFZ
Time frame:
2006
Subtotal
total travel:
€
€
7,000
7,000
€
€
7,000
7,000
=========
€ 366,000
2.2 Subproject
Project plan and timetable
109