GEOclips Volume 57 June 2019

VOLUME 57 . JUNE 2019

INSIDE: Embracing multidisciplinary

Embracing mul�disciplinary mapping mapping in Griqualand West

in Griqualand West I 1 Mapping in the Griqualand West area of creation of maps and databases which,
the Northern Cape Province is one of the as outputs, will be integrated to develop
Nick Baglow flagship projects of the Integrated and various thematic products that will be
Multidisciplinary Geoscience Mapping responsive to outcomes linked to land
CGS Drone Programme I 4 Programme of the Council for Geoscience, use planning, geohazard assessments,
and is used to integrate multidisciplinary hydrogeological and geoenvironmental
Christo Craill geoscience research, development and management, and economic growth
skills transfer. This multiyear project, through minerals and energy.
The CGS applauds its Master’s initiated in the 2018/2019 mapping
season, involves the acquisition of high- The Griqualand West project is composed
graduates I 5 quality digital geoscience datasets, the of six tasks which are correlated with

Nontobeko Scheppers a. View eastwards of the Ghaap Plateau underlain by dolomites, with Kuruman Formation BIF hosting old
asbestos workings. b. Fe deposit of Doornfontein conglomerate/breccia north of Wolhaarkop. The knee-high
Using thermal images to find polished surface on the boulder is attributable to repeated rubbing by rhinoceros in the area.

unknown water sources I 6

Henk Coetzee

New Sheba West orebody in

Barberton I 7

Nosiseko Bala

2nd Interna�onal Symposium on

Medical Geology in Africa I 8

Portia Munyangane

Career outreach programme in

Thomo Village, Limpopo Province I 9

Ponani Mthembi

The journey of a geoscien�st in
geoscience mapping and allied

research I 10

Neo Moabi

Sandstone sources of the Union

Buildings I 11

Rehan Opperman

Preliminary results from the 60 km MT survey line southeast of Prieska. The conductive zone is interpreted
as the terrane boundary.

2 I GeoClips

different scientific disciplines in the Council Environmental groundwater issues in the Kuruman area: refuse dumping (a); graveyards established in
for Geoscience. Within these tasks, there stream courses (b).
are numerous activities focussed on
largely overlapping areas. In this regard, execution of the Geological Mapping hydrogeological resources. Environmental
the current mapping programme marks task commenced in the vicinity of Prieska health issues included investigating the
a significant shift from former seasons, and continued towards the Kuruman– types and characteristics of sites regarded
which were often characterised by loosely Postmasburg region. This work has as potential polluters of groundwater
connected stand-alone activities, to a resulted in significant improvements to resources, and relating the land uses to
coordinated and streamlined approach the existing lithological and structural water chemistry.
taking cognizance of the interconnectivity databases and regional interpretations
of the various disciplines. The statutory of both basin and Cenozoic deposits. Geotechnical Mapping over three
Griqualand West project exemplifies these Some of the world’s largest economically sheet areas where there is township
multidisciplinary and integrated processes important iron and manganese deposits development revealed the prevalence of a
and addresses National Development are concentrated in this area. Geological number of geotechnical factors, including,
Plan imperatives by embracing three of mapping will specifically investigate inter alia, excavatibility problems, sinkhole
the Geoscience Mapping Programme the knowledge gaps of the stratigraphy formation, collapsible soils and inundation/
themes, namely: Geoscience for mineral and structural geology that control flooding. Although mapping at this
and energy resources, infrastructure and hydrothermal mineralisation (e.g. Cu- scale is not a substitute for site-specific
land use, and health, groundwater and Pb-Zn and Fe-Mn), and thus, the task is investigations (especially dolomite stability
the environment. All tasks undertook clearly linked to the Economic Geology studies), as it does not provide sufficient
fundamental mapping in the first season, task which seeks to understand the detail for in-depth planning, it can be used
and in this second 2019 season, field geological history and associated mineral for broader planning during the preliminary
mapping will primarily interrogate and genesis of the area to optimise the stages of investigation.
model existing data by means of the exploration and mining potential of the
targeted acquisition of further geological area. In addition to the above base metals, Beyond the familiar geoscience
and mineral deposit data. the Griqualand Basin is endowed with disciplines, the project seeks to embrace
primary and alluvial diamonds, tiger’s eye, the broader social context, including
Within the Geophysics and Remote limestone, travertine and dolomite, natural cultural heritage, biodiversity and tourism
Sensing task, previously flown regional aggregates, asbestos, diatomite and perspectives, as, for example, captured
airborne magnetic/radiometric data small-scale salt resources. Geochemical in the recently established provincial Go
were interpreted in support of ground surveys were undertaken over the non-BIF Ghaap! Route. The Geological Society
mapping activities. Cluster analysis was lithologies across a number of sheet areas of America Position Statement of 2014
successfully used to interpret these in the east. In addition, eight preliminary states that “earth science should be
large geophysical datasets. Remote geochemical atlases were produced from incorporated into all land and natural
sensing interferometric synthetic aperture existing geochemical data (23 elements resources management decisions to
radar (InSAR) data were used to map per sample with an improved 66 elements enhance their integrity and sustainability”.
and validate surface deformation and to be obtained from samples collected in The multidisciplinary approach to the
subsidence possibly associated with the 2018 season). Geoscience Mapping Programme is
sinkhole development in the dolomitic certainly the first step in unlocking the full
terrains of the Daniëlskuil and Kuruman In terms of the Hydrogeology value of the obtained geoscience data.
areas. In addition, standard geotechnical perspective, interrogating the existing
work was carried out in these two areas. and newly generated hydrocensus data For more information contact:
Additional acquired and interpreted led to the delineation of aquifer types and Nick Baglow
geophysical datasets included a ground- the production of hydrogeological maps Geoscience Mapping
based magnetotelluric (MT) survey, a when integrating lithological and structural +27 (0)15 295 3471
time-domain electromagnetic (TDEM) data, including identifying lithologies that [email protected]
survey, ground-based seismic refraction, are prone to rapid erosion and/or that
a reflection survey and remote sensing. control the flow and concentration of
Ground surveying was based on specific
problems and represented the first level of
a multidisciplinary mapping approach.

The Griqualand West area is underlain by
a complex sequence of interbedded, low-
grade, metamorphosed and structurally
deformed sediments, chemical sediments
and volcanic rocks which were extruded
in palaeoenvironments ranging from
terrestrial to shallow and deep water. The

Geoclips - Volume 57 - June 2019 GeoClips I 3

The Griqualand West project area depicting the 1:50 000-scale sheets covered by the various tasks in 2018/2019 and geological mapping to be
undertaken in 2019/2020.

4 I GeoClips

CGS Drone Programme

The Council for Geoscience has The DJI Matrice 600 Pro drone (left) and the smaller Geophysics and Remote Sensing Unit
embarked on a programme to establish DJI Phantom 4 Pro drone on the right. took the drones to Donkerhoek to
its capability for drone surveying. test the sensors. The reason for this
This programme will complement The DJI Matrice 600 Pro currently initiative was to introduce more people
the existing aircraft (fixed wing and allows access to optical and thermal to the drones and to identify individuals
helicopter), which will be equipped with sensors. This drone can take a who may be interested in being trained
the latest geophysical equipment for maximum payload of up to 6 kg and in flying them. The afternoon was a
future CGS surveys. was designed for industrial use. Not huge success, not only for testing the
only can it take a heavy payload in sensors, but for the individuals who
The Council for Geoscience is in the drone terms, but it also has a longer- tried their hand at piloting the drones.
process of obtaining a drone licence than-average flight time for its size. Project leaders are urged to make use
from the Civil Aviation Authority (CAA). The payload attachment fittings are of this mapping platform and to share
This licence will allow the Council for designed to incorporate a variety their needs and expectations to assist
Geoscience to use the drones for more of different payloads, is dustproof in establishing drones as a standard
scientific work by adding a variety of and can handle light rain or fog. The mapping tool.
sensors to the drones. The immediate procurement of a LiDAR sensor is in
administrative objectives, of which progress, while a hyperspectral sensor Two images showing the difference between a normal
some are regulatory requirements, and geophysical equipment will follow photo (top) and a thermal image (bottom), both taken
include an approved operating in the near future. by a drone. A shows a water tank that radiates much
manual, accepted standard operating less heat than its surroundings. B is a big tree that
procedures (SOP) and keeping the The planned geophysical equipment still radiates heat that was absorbed during the day.
licence up to date. The first group of that will be used on the drone will be a C shows an area with very little plant growth. The
pilots to obtain a remote pilot licence, magnetic system and/or a radiometric ambient temperature at the time the thermal image
as required by the CAA for a drone system. In order to ensure that the was taken was about 16 °C, just after sunset.
licence, will be sent for training in geophysical equipment is used
June and a second group will follow optimally and to the required standard For more information contact:
soon after. Currently, the Council for of the Geophysics Unit, the need for a Christo Craill
Geoscience is operating under a hobby drone with a bigger payload has been Geophysics and Remote Sensing
licence, which only allows use of the suggested. The planned geophysical +27 (0)12 841 1236
drones for observations with a normal drone will require a payload in the order [email protected]
camera and restricts the areas where of 35 kg.
flying is allowed.
On a late Friday afternoon, just
The Council for Geoscience currently before sunset, staff members of the
owns two multirotor drones, the DJI
Phantom 4 Pro Plus and the bigger DJI Drone pilot in training — Mihlali Hobo trying her
Matrice 600 Pro. hand at the controls of the small drone under the
watchful eye of Noluvuyo Dudumashe.
The DJI Phantom 4 Pro Plus has a
built-in optical camera and can only
take an additional payload of about
0,5 kg. This drone has been designed
for photographic purposes and the
quality of the photographs and videos
that have been taken in the field is
proof of the extraordinary observation
capabilities of this small drone. The
main purposes of drones of this
size are for general reconnaissance
surveys, to obtain a better view of a
specific area, to gather observations
of inaccessible areas such as marshy
and wetland areas, and the CGS drone
will also be used for the training of
future pilots.

Geoclips - Volume 57 - June 2019 GeoClips I 5

The CGS applauds its Master’s graduates

The Council for Geoscience wishes modern coastal processes. The results
to congratulate Wilhelm van Zyl, Zahn indicate a low-relief seafloor consisting of
Nel and Brian Zulu for obtaining their Malmesbury Group rocks in the north. To
Master’s degrees. the south, the seafloor consists of high-
relief Cape Granite reefs interspersed
with fine- to medium-grained sand and
bioclastic (shelly) gravel. Sediment
transport is generally northwards, by
longshore drift. In the south, the high-
relief granite reef and headlands form
sediment traps, resulting in several
large pocket beaches and offshore
sediment deposits. In the north, the
low-relief Malmesbury bedrock is largely
free of sediment, except within narrow
erosional gullies. Most sediment rapidly
passes through to the north resulting in a
sediment-starved rocky seafloor.

Wilhelm van Zyl The three principal sources of beach Zahn Nel
sand are aeolian fine sand transported
Wilhelm van Zyl received an MSc in by the Karbonkelberg headlands bypass Zahn Nel obtained an MPhil in Extractive
Geology from the University of Cape dune entering the sea at Sandy Bay, Industry Policy, Management and
Town, focussing on the geological biogenic carbonate production along the Regulation from the Faculty of Law,
mapping of the inner shelf off Cape coast, and weathering of Table Mountain University of Pretoria. This was the first
Town’s Atlantic Seaboard, South Group sandstone and granite bedrock. year that the faculty had opened the
Africa. The Atlantic Seaboard is an A fourth source is sediment entering the course to non-law students and Zahn
18 km stretch of coastline located on system via longshore drift from the south was one of the first two graduates of the
the Cape Peninsula, South Africa, of Duiker Point. The water depth around MPhil course. The course comprised an
roughly between the Cape Town the Duiker Point headland is too deep at (elective) online module and coursework
suburbs of Mouille Point in the north present for sediment to be transported components which culminated in
and Hout Bay in the south. The area easily through longshore drift, other than examinations and a minidissertation
borders heavy shipping traffic and during large storm events, but during (in addition to compulsory training in
contains a mix of urban and natural past sea-level lowstands this would have research methodology). Zahn chose
environments, including up-market played an important part in supplying to do an online module charting the
seaside neighbourhoods, and is part sediment to the coast. course of mining legislation in South
of the Table Mountain National Park. Africa — providing a perspective on the
The predominantly rocky coastline has Changes in sea level play an important various iterations of the MPRDA and
a northeast–southwest orientation with part in shaping the geomorphology of the the Mining Charter, in particular. The
interspersed sandy pocket beaches. A coastline. Beach deposits, both sandy coursework modules saw leading industry
narrow, low-lying coastal plain (marine and boulder beaches, have been left at representatives from various fields of the
terrace) in the north merges with coastal various elevations along the coast, both Extractive Industries presenting on their
cliffs further south. The geomorphology offshore and onshore. Although today the fields of expertise — covering issues
and sedimentology of the coast are Sea Point area is protected by sea walls relating to the rights to, and regulation
closely linked to the underlying geology, and man-made structures, a higher sea of, natural resources and sustainability
influencing the shape of coastal level was responsible for shaping the issues surrounding the extractive
embayments and promontories, as well narrow coastal plain. Increasing rates of industries. Zahn’s minidissertation was
as the composition and distribution of global sea-level change are becoming an entitled From building legitimacy to
sediment. important issue all over the world and the building networks: reconceptualising
Atlantic Seaboard coast is not immune the social licence to operate in the
Hydrographic, geophysical and to the effects of sea-level rise. The context of deep offshore mining. Given
sedimentological techniques were used frequency and magnitude of storm events the importance of the social licence to
to collect high-resolution bathymetry, that breach the sea defences erode operate in terrestrial mining operations
seafloor geology and sediment beaches and sea cliffs, and damage to — identified by EY as the most significant
distribution data to better understand private and public property is likely to business risk facing mining operations
increase in the future. in 2019–2020 — Zahn investigated

6 I GeoClips

the consequences of extrapolating this Brian Zulu was awarded an MSc in Period B. The highest estimated peak
concept to the domain of deep offshore/ Geophysics by the University of the ground acceleration (PGA) value was
marine mining. In particular, her research Witwatersrand. His MSc entailed a time- approximately 0.250 g for a return
focussed on a mining operation offshore dependent probabilistic assessment period of 475 years in the western part
of Papua New Guinea, mooted to of the seismic hazard along the of the region in Period A, while the
become the world’s first commercial- densely populated northern rim of the corresponding estimated PGA value was
scale deep sea/offshore mine. Witwatersrand Basin of the Gauteng 0.206 g for a return period of 475 years in
Province, South Africa. Seismicity in the same region in Period B. The spectral
Brian Zulu this region is mainly induced by deep acceleration values also decreased from
gold mining and flooding of worked- Period A to Period B. It was observed
out mines. To date, seismic hazard that the Far West Rand seismic zone
assessment in the gold mining regions contributes the most to the hazard in the
has not been incorporated in global study region, followed by the West Rand
projects such as the Global Seismic seismic zone and the East Rand seismic
Hazard Assessment Program (GSHAP), zone. The Central Rand seismic zone
although seismicity related to gold mining is the least active and is thus the lowest
activities accounts for about 90 % of contributor to the hazard of the study
seismicity in South Africa. region. The hazard estimates are higher
in the western parts of Johannesburg
Time-dependent seismic hazard than in the eastern parts of the city.
estimates are given in terms of peak
ground acceleration and 5 % damped For more information contact:
response spectra at periods of 0.1 s, Nontobeko Scheppers
0.5 s, 1.0 s and 2.0 s for 10 % probability Human Resources
of exceedance in 50 years (475 +27 (0)12 841 1201
year return period) for two different [email protected]
periods, namely Period A (1970–2004)
and Period B (2005–2015). Seismic
hazard estimates are higher in Period
A owing to higher activity rates than in

Using thermal images to find unknown water sources

On a misty morning, with the temperature warmer air from the moisture below will project team. The rainy season and
a chilly 8 °C on arrival, the thermal sensor come through the leaves and expose the the significant volume of water did not
on the DJI Matrice 600 Pro drone (see moisture below. allow for this point to be sealed. The
p. 4) was put to use in the Benoni area known ingress point is shown in the top
for the Mine and Environmental Water A drone was used to survey the area of lefthand corner of the image, where
Management Project (MEWMP). The aim interest and many images were taken readings show the highest temperature
of the field trip was to determine whether with the thermal camera. Areas that could (the white area). Just to the right of
unknown water sources would show up not easily be accessed and observed
on the thermal images. before on foot were observed from the Photograph showing the positions of images A and
sky and more information was gathered B. Image A depicts the location of past ingress
If a person were to think of a normal in three hours than would have been points that have since been closed. Image B shows
thermal image taken during the day, possible in a few days. a known ingress point that has not yet been closed
where the water would be cold and the owing to the high volume of water in the area.
ground and buildings would be warm, The thermal images distinctly show
this scenario will be reversed early in the waterbodies, even where some
the morning, when the air is still cold. areas are hidden under vegetation. In
Early in the morning waterbodies may be image A, there used to be an ingress
covered by a layer of mist just above the point of surface water, known as the
water. During the warmer part of the day, Modderbee crack. This point has been
plants will bake in the sun and radiate sealed off and there are no signs of
this heat. Early in the morning, however, water disappearing into the crack
the thermal sensor will pick up that the visible from the surface. Image B
plants have not warmed up yet, and the shows a point of ingress known to the

Geoclips - Volume 57 - June 2019 GeoClips I 7

Image A — The blue to green parts represent the In this photograph, only grass is visible in the area Possible moisture showing up in the thermal image.
solid ground, whereas the yellow to red/white parts indicated by the arrow. The arrow shows the central On the normal photo, only grassland is visible, with
represent the waterbody. point of the thermal image on the right. no appearance of water seepage.

the white area, where the white and information that was unknown before.
red colours become intermingled, Scientists are encouraged to make use of
mud is depicted. The area is currently this mapping platform, not only to obtain
covered in vegetation and, had a more information from photographs,
normal camera been used, all the water but also to obtain more information
flowing underneath the mud would over larger areas and to reach better
have gone unnoticed. Areas of concern conclusions.
were identified and will be further
investigated.

Image B — The blue to green parts represent With this new technology, areas that used For more information contact:
the solid ground, whereas the yellow to red/white to be difficult and dangerous to access Henk Coetzee
parts represent the waterbody. The areas where or that may even have been hidden from Water and Environment
green and yellow are mixed represent mud. The plain sight can now be discovered and +27 (0)12 841 1398
white colour in the top lefthand corner of the image captured with photographs or a video. [email protected]
represents a known ingress point. Thermal imagery produces not only
spectacular images to enhance a report
or presentation, but also serves to reveal

New Sheba West orebody in Barberton

The Sheba West ore deposit is processing techniques to exploit these
located west of the Sheba Mine in orebodies in an efficient and profitable
Barberton, Mpumalanga. The Council manner. The industry is expected
for Geoscience is participating in a increasingly to partner with universities
programme of geometallurgical studies and research companies to assist with
on selected ore deposits across South the research and development of new
Africa. This Economic Geology research gold recovery technologies.
programme falls under the CIMERA
Centre of Excellence umbrella. The Identification of ore minerals using microscope
aim of the project is to boost research studies.
and develop new technologies for gold
recovery in South Africa.

The increasing worldwide demand for The CGS team embarked on underground reef The identification and characterisation
metals and growing pressures of the sampling at the new Sheba West Mine located in of ores are important for metallurgical
global economic downturn on the mining Barberton, Mpumalanga Province, South Africa. processing. The detailed characterisation
industries necessitate the economic of ores will contribute to the
extraction of metals from lower grade establishment of an efficient beneficiation
ores, which in turn requires efficient system. Ore mineralogy must address the
beneficiation methods. The current geological and engineering challenges
under-exploration of high-grade ores of a mine, as well as beneficiation
has resulted in the need to enhance and metallurgical treatment options.

8 I GeoClips

Therefore, careful mineralogical analysis geometallurgy of South African ores. For more information contact:
of ore is necessary to determine the The results of the study will be published Nosiseko Bala
feasibility of the ore for metal extraction. in scientific journals and be presented Economic Geology and
at conferences, both locally and Geochemistry Unit
The project involves a collaboration internationally. This research will extend +27 (0)12 841 1402
between the Council for Geoscience, the life of mine and create prolonged [email protected] 
Barberton Mines, the University of employment opportunities for mining
the Witwatersrand and the University communities, while contributing to the
of Limpopo, and focusses on the eradication of poverty.

2nd International Symposium on Medical Geology in
Africa

The second International Symposium Portia Munyangane represented the Council for elements that may either be potentially
on Medical Geology in Africa was harmful or beneficial at a certain level.
organised and hosted by the University Geoscience at the International Symposium on Twenty-nine (29) borehole water samples
of Johannesburg and accommodated were collected in the Giyani area, 15
more than 50 delegates from different Medical Geology in Africa. from boreholes in the community and 14
countries and scientific institutions. from primary school boreholes, and these
The main purpose of this meeting was In general, South Africa is a water-scarce samples were analysed for five potentially
to provide a platform for discussion, country with very low rainfall compared toxic trace elements: arsenic (As),
development of research and training of to global rainfall averages and, therefore, cadmium (Cd), chromium (Cr), selenium
students in medical geology, as well as the region lacks perennial streams over (Se) and lead (Pb), using Inductively
to share experiences, lessons learnt and large areas. Consequently, most rural Coupled Plasma-Mass Spectrometry (ICP-
to seek solutions to various geological communities rely on borehole water as MS). In order to determine the suitability of
and environmental health issues. The their only source of water supply. There is the borehole water for drinking purposes,
conference consisted of a two-day short a general perception that borehole water trace constituent levels were compared
course with discussions, followed by a day is pure and clean because it originates with the South African National Standard
of oral and poster presentations under from underground, but this is often not for drinking water (SANS 241-1:2011).
three symposium themes: soil and medical the case. Groundwater contains chemical
geology, environmental health and its Elevated arsenic levels were detected in
impacts, and dust toxicology and medical four boreholes. Two boreholes had arsenic
geology. concentrations more than five times that
of the South African National Standard
Portia Munyangane, from the Council for acceptable limit for drinking water of
Geoscience, presented a talk titled: Toxic 10 µg/L. Considering the spatial distribution
trace constituents in borehole drinking pattern of arsenic concentrations in
water of the rural Greater Giyani area, the study area, it appears that arsenic
South Africa, under the environmental
health theme. Her presentation is part Spatial distribution of arsenic concentrations in the Greater Giyani area in relation to the geology.
of her research work on groundwater
quality assessment in the Greater
Giyani area, Limpopo Province. The
investigation is attempting to answer the
following questions: What are the levels
of potentially harmful trace constituents
in the borehole drinking water? How are
these trace constituents distributed in the
South African environment? What are their
environmental and health implications?
These are questions which, until recently,
South African geoscientists could not
answer satisfactorily owing to little or
no attention being paid to the possible
presence of harmful trace constituents in
the environment.

Geoclips - Volume 57 - June 2019 GeoClips I 9

occurrence is highly influenced by the bladder, kidneys, lungs and skin, as well In cases where elevated levels of arsenic
underlying geology and mineralisation. as other non-cancerous health effects, are detected, the authorities should make
The boreholes with the highest arsenic such as skin tumours, hyperkeratosis, sure that alternative water sources are
concentrations are found within the Giyani hyperpigmentation, and respiratory and used or they should invest in treatment
greenstone belt, which is known to host cardiovascular illnesses. technologies for the removal of toxic trace
arsenic-containing sulphide minerals. constituents.
To protect the community in the study
This research unearthed worrisome area against arsenic exposure when For more information contact:
health concerns, suggesting that the drinking borehole water, public and Portia Munyangane
continued intake of water from boreholes private boreholes must be tested Geoscience Mapping
containing elevated levels of arsenic to ensure that they contain arsenic +27 (0)12 841 1473
may cause a wide range of adverse concentrations less than the South [email protected]
health effects including cancer of the African National Standard allowable limit.

Career outreach programme in Thomo Village,
Limpopo Province

Khomanani Thomo Forum, a non-profit feeding the poor and assisting the youth A large number of learners attended the career
organisation, was started in 2012 by a with initiatives such as career guidance. outreach programme in Limpopo Province.
group of young people who are now based This year they decided to organise
in Gauteng Province, but who hailed from something new that will become an annual also explained to the learners that there
Thomo Village under the Shiviti Traditional event in the community in the future — a are many opportunities in the geoscience
Authority in Giyani, Limpopo Province. career outreach programme. The forum field. This event provided an opportunity
The young people decided it will be good was started in 2012 but this event is the to increase community awareness around
for them to start an initiative that will be first of its kind organised by the forum. They the Council for Geoscience and its work.
able to assist their community in Limpopo. invited different stakeholders and investors Rethabile Makwela engaged with the
The aim of the forum is to encourage from government and the business sector leaners and distributed marketing material
continual relations and a learning culture to participate in the event held in the in order to increase brand visibility. A
amongst the members of the community Thomo community hall in Giyani on 11 May number of learners showed keen interest
who live in and around Thomo Village and 2019. The Council for Geoscience was in obtaining more information on bursaries
to assist with development in the village by amongst several companies who had been and career opportunities offered by the
ploughing back to the community the skills invited to attend the exhibition and was Council for Geoscience. Officials of the
and knowledge gained over time. requested to do a formal presentation to local government and the Department of
the high school learners from the area. Education were present, which increased
The forum initially considered money- the visibility of the Council for Geoscience
saving methods such as community The attendance was good, with close among its stakeholders in the area.
stokvels or burial societies, but rather opted to 200 learners attending the career
for a programme to help the children from outreach programme. The learners For more information contact:
their village by supplying school uniforms, were mostly from Hanyani Thomo High Ponani Mthembi
School, with a number of primary school Geoscience Mapping
Ponani Mthembi created awareness regarding learners attending. School uniforms +27 (0)15 295 3471 
career opportunities offered by the Council for were handed out to these learners. [email protected]
Geoscience. Companies and professionals who
presented included a pharmacologist, an
artisan, an attorney, an artist and a chief
financial officer, amongst others. Ponani
Mthembi from the Council for Geoscience
presented information on the geoscientific
opportunities and requirements needed to
follow a career in the geosciences. Most
learners had no prior knowledge about
what a geologist does, or what the field
of geology entails. Ponani gave a brief
overview of the subjects needed in high
school for admission to university and

10 I GeoClips

The journey of a geoscientist in geoscience mapping
and allied research

Neo Moabi was introduced to the world Polokwane Office Neo Moabi in the field, mapping the Malmani
of the geosciences in 2004 when the
Council for Geoscience awarded him In the Polokwane Office, Neo worked Dolomites.
a bursary to study Geology at the in a wide range of geological terrains
University of Pretoria. He completed where he acquired extensive knowledge contributed to ensuring compliance
his studies well in time and was of the South African geology. During with all applicable SHE policies and
immediately appointed by the Council this time, he mapped the high-grade procedures in line with set standards
for Geoscience. For the past ten years, metasedimentary and metavolcanic and good housekeeping principles in
Neo has been a loyal and responsible rocks of the Limpopo Mobile Belt in the workplace.
employee who conducts his research the Musina area and of the Gariep
and tasks with enthusiasm and Supergroup in the Richtersveld, as In 2013–2014, he was involved in the
determination. He started his mapping well as the rocks of the Transvaal Antarctica project. The project afforded
career in the sophisticated marine unit Supergroup in the Legalametsi area. him the opportunity to study towards
of the Bellville regional office before During this field mapping period, he an MSc degree in Geology, which
he was selected to attend a year-long gained knowledge in the use of a wide he undertook and completed in good
Field Mapping course (known as the range of geological mapping tools time. During this time, he studied the
Field School) in the Polokwane regional such as the GPS for positioning, the geochemistry and palaeomagnetics
office. After completion of the field Freiberger, Brunton and Silva Ranger of the Espungabera Formation
school, he was transferred to Pretoria compasses for collecting structural lavas of Central Mozambique and
where he is currently based. measurements, ArcGIS for map the Straumsnutane Formation lavas
production, the optical microscope for in western Dronning Maud Land,
Marine Geoscience Unit petrographic studies and Grapher 7 and Antarctica. Neo presented his findings
Winrock software for geochemical plots at multiple international conferences
During 2008, in the Marine Geoscience and analysis. and published his work in international
Unit, Neo was involved in a number peer-reviewed journals. Amongst other
of marine geological surveys where Pretoria Office projects, he is currently a task leader of
he acquired skills in the collection, the Griqualand West mapping project.
processing and interpretation of side- Neo joined the Pretoria head office
scan-sonar data, marine seismic and team were he was tasked to put all the
magnetic data, and bathymetric data, acquired skills into action by executing
all thanks to the senior scientists of a wide range of mapping projects
the Marine Geoscience Unit who were while at the same time increasing his
great mentors. Non-scientific skills, knowledge of the fascinating world
such as offshore survival and helicopter of geoscience. In 2011–2012, Neo
underwater escape skills, were also was involved in the Thyspunt Nuclear
acquired. Many lessons were learned Siting project. His duties included
such as “recovering from a good night the supervision of drill sites, core
with a bit of a hangover and being sea logging and sampling, as well as
sick at the same time is not a good maintaining a healthy environment,
idea”. safe operations and practices. He

For more information contact:
Neo Moabi
Geoscience Mapping
+27 (0)12 841 1087
[email protected]

Neo Moabi collecting side-scan-sonar data (a). Suffering from sea-sickness in the boat (b).

Geoclips - Volume 57 - June 2019 GeoClips I 11

Sandstone sources of the Union Buildings

The main building stone used for the Pienaars River stone near Hammanskraal, as a cost-saving measure. Dr A.L. Hall
construction of the Union Buildings is used in the amphitheatre retaining walls, published a photograph in 1905 in
sandstone. Except for the Transvaal was of dubious quality. The exact locality Memoir 1 of the Geological Survey of
Supergroup sandstone obtained from of this quarry is not known. South Africa of the quarry on which the
Meintjeskop itself, the other sandstone Union Buildings would eventually be built.
used in the Union Buildings appears to Except for the outer walls, Balmoral This quarry was incorporated into the
have been obtained from the lower Ecca sandstone from between Pretoria and structure of the Union Buildings.
Group and the Clarens (or equivalent) eMalahleni (previously known as Witbank) During 1910, a small private quarry west
Formation of the Karoo Supergroup. was likely also used for the retaining of Ficksburg in the then Orange Free
wall in the amphitheatre as well as the
One of the best-known quarries that was lower retaining wall above the old tram Google Earth image of Steenpan, south of
a major supplier of sandstone to buildings line. Dr Kynaston mentioned in the 1910 Vereeniging.
in Johannesburg and Pretoria for many Annual Report that there were three
years is Steenpan, also referred to as quarries, one at Kleinwater and two at
Meulsteenpan/Molensteenpan (English: Kromdraai. It would seem that many of
Millstone Pan) near the Wolwehoek railway these sandstones did not weather well.
station, south of Vereeniging. This quarry
was the biggest source of sandstone Sandstone was also obtained from the
for the Union Buildings project. In the ridge on which the Union Buildings were
1910 Annual Report of the Geological built and from the excavations for the
Survey, it is mentioned that the quarry construction of the basement, probably
was originally opened around 1892 for the
northward extension of the railway line from
Bloemfontein.

Different variations of sandstone, such
as Steenpan no. 1 and 2, Klippan and
Flatpan, were worked. Various horizons in
the quarry offered differing qualities and
were allocated separate uses. Flatpan, also
referred to as Vlakpan, was considered
to be the best-quality sandstone from the
Steenpan Quarry.

The firm Rowe, Marshall & Fleming A portion of the Flatpan Quarry (Annual Report of the Geological Survey for 1910).
advertised in “The African Architect” in 1913
that they supply “freestone” (so named
because the rock can be freely cut in any
direction) from the Flatpan and Steenpan
Quarries. The company listed that it had
been contracted to supply 400 000 cubic
feet (approximately 11 300 m3) of freestone
for the construction of the Union Buildings.

Sandstone was also obtained from Red sandstone quarry, Buiskop, near Bela-Bela (Annual Report of the Geological Survey for 1910).
Buyskop/Buiskop near the town of Bela-
Bela (previously named Warmbaths). The
sandstone is a reddish equivalent of the
Clarens Formation sandstone of the upper
Karoo Supergroup. This sandstone was
used for walls, base courses, columns
and paving of the Union Buildings. It was
also used inside the Union Buildings as
decorative chequer pattern floor tiles, and
stylish staircases and walls in the two inner
courtyards.

Mining of Balmoral sandstone on the farm Kromdraai (Annual Report of the Geological Survey for 1910). State (now Free State Province) also
supplied some high-quality stone for
ornate carvings and decorations. The
same quarry still supplied stone between
1980 and 2000 for various restoration
projects at the Union Buildings.

Other known sources that produced
sandstone but that could not be
confirmed for being used for the
construction of the Union Buildings
include Eland River sandstone east of
Pretoria and Stinkwater sandstone west
of Hammanskraal. Mention is also made
in literature of quarries near Ermelo,
Brakpan and Boksburg. No reference
could be found that the well-known
Waterval sandstone from a quarry north
of Bon Accord was used.

The sandstone has stood the test of
time with varying degrees. During
restoration work, some sandstone blocks
and carvings have been replaced with
sandstone from alternative sources,
e.g. Klippan sandstone used for paving
has largely weathered away and has
been replaced with stone from the
Mookgopong (formerly Naboomspruit)
Quarry during renovations in the 1980s.
None of the Buyskop sandstone has so
far been replaced. Normal weathering
processes and pollution will require
ongoing restoration work to the Union
Buildings.

Glass negative image of a photograph by Dr Hall (Geological Survey, Memoir 1, 1905) of the quarry where For more information contact:
the Union Buildings would be built a number of years later. Rehan Opperman
Economic Geology and
Geochemistry
+27 (0)12 841 1121
[email protected]

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