2014 Diary: Day 19 - Goodbye

By Nick Baglow:

As another Field School draws to a close, with just the Polokwane crowd to actually return home, one can reflect on a few highlights of the last few weeks. One of course has been the inauguration of the blog itself! Another was this year’s group of young participants; they gelled  well  throughout and were an example of coming from different competencies and offices within the repositioned Council and functioning effectively together, scientifically and socially. Besides the obvious learning of geological mapping techniques this has always been a component of the Field School; to recognize that geology is cool and geologists/colleagues are fun people (when liberated from the confines of the office!). We had a larger group than in previous years, but retained the successful model of having three rotating participants per trainer to ensure personal attention and development, and the interest maintained by the group to the very end once again  justified this approach.

On the journey across South Africa a diverse assemblage of exposures across the stratigraphic spectrum was  visited and these have  been documented in earlier blogs. As a follow-up the Field School participants have now been allocated individual research topics (related to that journey) that collectively will enhance the group’s broader understanding of the geological context of what they encountered. This research will be included as addenda to their reports on the actual mapping area in the Richtersveld.

The topics are:

1 Snowball Earth (Shane)

2 Dinosaurs; definition, extinction at the K-T boundary (Penester)

3 Aeolian sands, red beds (Eveline)

4 Mafic dyke swarms in SA (Ndidi)

5 Continental flood basalts (Ntsundeni)

6 Greenstone Belts…what are they? (Belindah)

7 Orange River diamondiferous gravels (Mpumelelo)

8 Stromatolites, biomats…modern and ancient (Khaya)

9 Pillow lavas … modern and ancient (Olma)

10 Whitehill Formation… shale gas potential (Haajirah)

11 Dwyka  Group across continents (Tebogo)

12 Tidal sandstones, ripples and palaeocurrents (Ngqondi)

2014 Diary: Day 18 - Exit, pursued by a Bear

Goodbye Sendelingsdrift! The team finally departed our favourite trans-frontier National Park amid sunshine and cloudy skies. This mixture of light and dramatically rugged mountains provided a grand scene for our exit. In fact, the beauty was way too intense to be photographed! Our final order of business in this region was to once more visit the Johan Hein School in Kuboes. Here we had an official hand over of some school equipment (pens, pencils, erasers, bags, etc – Thank you Council for Geoscience, may you always remember the less fortunate and continue to strive in upliftment and development).

Top: View of Kuboes, Bottom: Nick explaining Kate's groundwater poster and Tshimane performing an official hand over of the poster and school supplies to Mr de Wet

 As mentioned in earlier posts, groundwater is essential to the survival of much of these communities, however is rather poorly understood. Information on groundwater stems from years of natural understanding, however with factors such as climate change and the changing in the intensity of weather patterns, it would be highly beneficial for these communities to be informed on these factors. This may potentially aid in sustainability and avoid vulnerability of the largely herding community.  With this in mind, one of our expert hydrogeologists, and fellow Richtersveld mapping geologist class of 2009, Miss Kate Robey produced an immaculate poster highlighting groundwater and its relationship with the surrounding geology. These posters were really welcomed and received by a senior staff member, Mr de Wet. It is envisioned that this simple gesture of information sharing may spark the hunt toward understanding a changing climate and how we might have to evolve as consequence to it. This also ended the Richtersveld Science Week! During this time we managed to have a townhall meeting in Eksteenfontein, also meeting/workshop with the local educators; school lecture in Kuboes and once more meeting/workshop with the educators. We were also fortunate to create several information posters and hand over some stationary and teaching aids. This is a minor step toward something we hope could grow into a larger outreach programme. Once more, if there are any suggestions, comments or if you would like to be involved, please do not hesitate to contact us (tdhansay@geoscience.org.za).

2014 Diary: Day 17 - Tillites are not a girl's best friend

Today was the final mapping day of the Field School 2014! Our participants were visibly upset and some even chose to stay out in the field for longer than usual. A large team that included Taufeeq, Ngqondi, Sims, Eve, Judy, Ndidi and Olma set out to answer some questions and recap the Gariep Belt history. This team travelled the top of the basal thrust zone, exposed within the Western region of the mapping area. This zone includes the tectonic melange, recently mentioned and comprises of large (meter-thick) thrust faults that have stacked diamictite and quartzite in a repetitive nature along at least five noticeable thrust packages. Based on the steepness of these faults, the team opted to spend some time practising their 4X4 skills before trying to quell some lithostratigraphic issues.

4X4 training was done with the basal thrust packages as a backdrop, literally. Participants engaged the low-range gear of our VW Amarok and attempted to crawl gently up the steep, rock slopes. All of this before having to perform a three-point turn and crawl back down. This is vital skill needed when driving in this kind of terrain and since we’re all alive now, everybody passed this test with flying colours!

Slow and steady, keeps you alive! Low-range crawl down a slope

Now, problem number one: what is a diamictite; what is a tillite:

A diamictite is essentially a sedimentary rock that has a matrix (fine-medium grained) and at least two different kinds of clast. This is as opposed to a conglomerate that mostly has one type of clast, commonly quartz pebbles. Now, a tillite is a diamicitite (i.e. matrix with at least two different kinds of clasts), but it has been deposited through glacial processes. Moreover, how do we distinguish these two rock types in the field?! Well, without the presence of proper drop stones (clasts that have “dropped” into sediment and caused soft-sediment deformation) this is very difficult- thus geology.com recommends diamictite as a safe name for “careful” geologists.  It will be interesting to see how our team handles this based on what they've seen in the field and what the literature elucidates to.

Spot the Diamicite/Tillite? Notice the dropstone!

Tomorrow further fears and questions will be quelled as we slowly make our exit from the Richtersveld!

2014 Diary: Day 17 - Diamictites are a girl's best friend

By: Nick, Tebogo, Penester and Khaya

Tebogo showing that the diamictites can be your friend in certain circumstances!

Well only in the Richtersveld perhaps, and only on another sun-drenched day, but after the singular (but expected!) non-success in earlier diamond quests among Orange River gravels, team attention went beyond the terraces to the rocks just above the basement of the last few days. The barren landscape is often almost surreal with quartz-covered plains contrasting with the dark desert varnish-covered outcrop ridges, though the geology today was relatively consistent overall. Largely Kaigas diamictite, with variably-sized clasts throughout, in this area the largest being carbonates along with various granitoids. The fine-grained matrix is generally sheared, with spaced phyllitic zones a feature, forming knife-edged outcrops protruding through the prevailing scree. The contact zone with the basement granodiorites and conglomerates and siltstones of the Vredefontein Formation is however marked by a gap in outcrop rather than spectacular thrust.

Clockwise from top left: the thorn among the roses; the contact between the basement granodiorites in the left foreground and the metasediments of the Vredefontein Formation; the zone proximal to the thrust though is marked by numerous quartz veins; a drawback of removing your boots during lunch break is that they may disappear!; you’re not looking for these boots are you? 

2014 Diary: Day 16 - Decollement

Our other team (Taufeeq, Olma, Khaya and Michelle) went out looking for big thrust faults, specifically around the basal thrust zone of the Gariep Belt. After the deposition of the Gariep Belt rocks (associated with the breakup of Rodinia ca. 750 Ma); this package was obducted onto the basement Vioolsdrift rocks during the amalgamation of Gondwana. In order to better understand the scale of this process, Olma, Khaya and Michelle (our esteemed guest from the office of the COO) traversed across one of the major thrust faults in a zone of major faults separating the Gariep from the basement. This was no easy feat, and highly dangerous- we of course maintain the highest levels of safety and security (and not just when we have guests from the office of the COO…). 

The entire fault zone extends for several kilometres and increases in topographically high peaks toward the top of the thrust succession. This provides some idea of the thrust direction, kinematics and strain partitioning throughout this sequence. Ductile deformation was present in the diamicitite, with now rotated clasts illustrating thrust transport direction along a top-to-the-west sense of motion. In addition, the quartzite of the Stinkfontein suffered under the strain partitioning and displayed very high levels of shearing and the formation of thin foliated layers. Finally, within each thrusted block (bounded by metre-thick vein quartz brecciation), a tectonic melange was present, where rocks buckled under the immense pressures.

Jumping for Joy: Olma and Khaya hunt for thrust tectonics. Bottom left: Olma showing one of the thrusts

With the temperature reaching above 40 degrees Celsius the team did not attempt trying to get down the steep thrust. Did not try to get down today, I should add. Tomorrow is a new day and likely to be a better day to attempt this! This will unfortunately have to be done without Michelle, who will return to Pretoria tomorrow. Michelle admitted that she enjoyed her visit to the Field School: “I would love to come back…” she said. And she will always be welcomed!

Until tomorrow- the final day of field mapping, here’s hoping to go out with a Bang!

2014 Diary: Day 16 - The Low's Revisited

By Nick and his team (Penester, Haajiera and Ndidi)

Today saw the return to the previous area in the north, partly necessitated by travelling for just over 3 hours to the last outcrop of yesterday to recover Nick’s hammer…a small sacrifice in comparison to the effort of procuring a new one! Plus a worthwhile exercise in GPS navigation, so all was good. The day was once again spent in basement, but this time with more variety in that extensive development of largely intermediate to felsic volcaniclastic metasediments was encountered along with the granodiorite. Dykes of the Gannakouriep suite are widespread, with dykes intruding earlier bodies being a subject of interest. A quick escape down to the Orange River (the juxtaposition of river and desert is a highlight of the Richtersveld) to cool down was successful; the search for a possible diamond in the river gravels was not!

Clockwise from top left: ‘Hand of God’ eroded into the sheared basement metavolcanics; team scale perspective; Gannagariep dyke-intruding-dyke exposure; Nick at the granitoid contact with his re-claimed hammer, Haajirah getting her chance to develop 4x4 skills in the real environment; Nick, Ndidi, Penester and Haajirah escaping the 40+ deg desert heat today; Penester overcoming one of her field ‘fears’ (spot the little bird) :)

2014 Diary: Day 16 - Neo-gee

By Neo and his team (Ngqondi, Tebogo and Shane)

Clockwise from the top: Ngqondi and Tebogo standing on a contact between the Tillite belonging to the Numees Formation Group and the Meta-Pelite of the Holgat Formation; Neo describing the intersection of a foliation plane perpendicular  to bedding - possible fold axis in the phyllitic shales of the Holgat subgroup and An outcrop of metapelite rock interlayerd with shales and wackes beloning to the Holgat subgroup of the Port Noloth Group.

2014 Diary: Day 15 - And the Lows

From Nick and his Team

One of the other teams did the opposite; traversing the low country in the north of the area. Michelle was visiting from Head Office and we were out to impress: the search was for basement volcanic rocks, but these proved rather to be rather enigmatic and sparse. Penester (Economic Geologist mind you!) summed it up: ”I’ve seen enough granodiorites to last a lifetime”. We couldn’t really disagree…

Clockwise from top left; Basement Granodiorites of the Vioolsdrif Suite, locally highly sheared but still the same unit; Shane and Penester capturing the details, contemplating the more varied geology on the Namibian side of the Orange River, “you can’t fool me, these are still sheared granodiorites!”

2014 Diary: Day 15 - Reaching New Heights

Today some our team members reached new heights, literally. Here we follow Ngqondi, Haajiera and Ndidi as they summit some of the higher peaks within the Richtersveld, all in the name of geology. The day started relatively simple with a short section into what’s fast becoming quite the controversy, namely the difference between a sheared tillite, or sheared diamictite. Tillite being a diamictite (conglomeratic rock with at least bimodal clast type) deposited by a glacier, and a dimictite deposited by any other means. A short section to the west of the main gravel road outside the National Park gates would show a simple stratigaphic change from diamicite/tillite to carbonaceous shales and dolomite, likely being part of the upper Hilda Subgroup (Wallekraal into Dabie River formations).

Some ptygmatic folding within the Phyllite units, and the team doesn't look to phased by the altitude

Later in the day, this team then began a section through, what they would later discover, a tectonic melange. This section involved climbing some 500 m through a thrust stacked sequence of phyllite, dolomite and siliclastic sediments. Several sequences were found to be repeated due to repetitive thrusting. These thrusts were clearly marked with the presence of thick brecciated vein quartz and an increase in the foliation. The dramatic topography was also discovered to be as consequence to the immense thrusting in this region with the upper peaks thrust-bounded with breccia. Lower diamicitite and phyllite had undergone ductile shearing and developed clear shear sense indicators. These all illustrated a top-to-the-west sense of shear, maintaining consistency with the regional shearing direction. This was a structure-heavy section and will really test the team’s abilities of interpreting the field relations and illustrating it on their geological maps.

High, but Haajiera getting even higher!

After the hike the team felt good. Ndidi was asked about her experience and said: “Haai, no this was too much…”. Rest will be well deserved this evening, and they’ll need it before tomorrow!

2014 Diary: Day 14 - The Sea That Took the Old Man Away

Every now and then the field school has one day off; and that was today as the team travelled to Port Nolloth to do some shopping and spend some time at the beach. The shopping was however, unsuccessful as we were chased away from the local Spar. Having arrived just on closure time (Spar in Port Nolloth closes at 12h00 on Sunday’s) the team was unfortunately turned away by the manager: “NO WAYS…” he roared as the team begged to buy food (meat and vegetables). “Safety Reasons” we were told. I suppose that must mean that we’re looking a bit rough after a few days in the field; and that must mean that we’re doing something right?! In any case, the team was quite disappointed in the way we were treated and had to leave empty handed; and empty stomached.

Port Nolloth has long been known as the gateway to the Richtersveld. From Port Nolloth the road north passes through Alexander Bay and the Orange River mouth (a long way from the Gariep Dam). This is of course of special interest with regard to alluvial diamonds that have travelled across South Africa along the Orange River. Following Alex Bay, the road enters one of the most scenic parts of South Africa, the desert setting around Groot Derm and into southern Richtersveld. Originally, Port Nolloth was the major exporting point for copper (from the Okiep District) and diamonds (Orange River mouth).

After the Spar incident, moods were lightened with Tebogo’s second ever visit to the beach! And, this time she was duly dumped into the ocean (All in good fun). Sand castles were built, ball games played and plenty of time given for sun bathing. Dark clouds quickly loomed, and must mean that it’s time to get back to the field…

Field School looks like way too much fun

2014 Diary: Day 13 - Gannakouriep in 60 seconds

As we near the end of the first week of field work, it's becoming very clear that our teams are very well set in their mapping. The rock descriptions and structural measurements are of the highest quality and we'll be expecting great results at the end of this year's field school. Of course, slight complications do arise in the field. Today, we follow Penester, Shane and Eveline. This team traveled deep into the Richtersveld in an attempt to complete one of the more isolated sheets. This journey was long and arduous, and could have easily warranted a fly camp. In the end, the planned traverse was not possible, due to current soil rehabilitation programme in an exceptionally long drive.

Team putting the Amarok to the extremes of its capabilities

Subsequently, this team did some regional mapping. Firstly, looking at some of the Gannakouriep dykes and later extrusive felsic volcanic rocks. The Gannakouriep dykes were emplaced during the early stages of the Gariep Orogeny, ca. 717 Ma; and represents the maximum age of this orogenic event. In addition, these dykes show evidence of deformation in places, related to syntectonic emplacement; and displays a very strong foliation. In places, the Gannakouriep could be seen near bright felsic volcanics, together these bounded within the Vioolsdrift basement gneisses.

Despite the lack of intense geology, the team did manage to test a VW Amarok along some of the moderately challenging tracks within the Richtersveld National Park. With a low ground clearance (approximately 205 mm - with 265/70/16R BF Goodrich AT) and a 2.0 liter Bi-turbo engine, producing only 132 KW of torque (enough the carry passengers and rock samples), the Amarok does not necessarily convince relative to bigger Toyota's. However, it managed surprisingly well (just needing to be taken very slowly over the tricky sections, to avoid scratching the undercarriage). Dragging the towbar could not be avoided though - the approach angle is simply not sufficient (due to the bling-bling nudge bar). Off-roading gadgets are plentiful: hill assist, electronic differential lock and anti-slip regulation, all of which goes a long way to making the drive as comfortable as possible. 

Geology-wise, note that there are lots of steeply foliated carbonates and quartz-rich shears along most of these roads. These develop razor sharp edges that will slice through the relatively soft rubber compound of the BFG's. It's worth noting that this particular Amarok had BFG tyres fitted 3 months ago and are now horribly gutted and pitted. Luckily, the team hikes most of the time and are well prepared for any potential quagmire-situation.

Final assessment: 6/10.... Until you get stuck, of course.

2014 Diary: Day 12 - Curious Kids of Kuboes

The Richtersveld Science Week continued today as the team travelled to the Johan Hein lower grade school in Kuboes. Here the learners are currently busy with their end of year exams and will be writing Astronomy and Geography soon. With this, a special lecture and crash course by Conrad Groenewald (the unofficial Burgermeester in many parts of South Africa) was exactly what the learners needed! Kuboes is particularly isolated with the community relying almost entirely on tourism (Richtersveld National Park), farming (small-scale nomadic sheep and goat farming) and mining (alluvial diamond mining). Being this isolated, the school and learners were extremely appreciative and welcomed the team (with participants from all over South Africa) warmly as nearly a hundred learners packed the school meeting room. Children from grade 4-7 were all enthralled and actively participated in the very hands-on approach by Conrad.

Conrad explaining the universe to the learners of Johan Hein school, Kuboes. Some of the kids weren't easily persuaded and didn't mind challenging Conrad! A great Science Day! 

The lecture began with an overview of the Earth and it’s interaction with the sun and the moon. Thereafter the learners were taught how to remember all the planets, in Afrikaans:

Meneer Van As, My Jas Sal U Nie Pas! (Let’s see if you can translate that!)

With a solid backing on the stars, planets and universe, the talk shifted to the Earth and covered various topics on geology, geomorphology and geography. Incredibly, Conrad managed to squeeze all these topics into a short period of 90 minutes and kept the children entirely entertained the whole way through. The children were also allowed to ask questions, some of which almost managed to stump the team! Quite a surprise; and proving that brilliant minds come in all forms and in all locations.

After the lecture, the team interacted and spent some time with the children. The kids were especially interested to meet fellow South Africans from as far afield as Venda, a meeting that neither party will easily forget. Simple interactions like these allows us a chance to look back upon our own lives and makes us realise that there’s so much out there. So much to explore, experience, and give back. Even the most simplest of gestures can make a wonderful difference.

The Richtersveld Science Week will go down as a major success. If we were able to ignite curiosity in just one of the young minds in Eksteenfontein and Kuboes, then the team of this year can feel extremely proud. Future plans will now be to try and build from here and expand the Richtersveld Science Week 2015 into a grand science affair! If you have any ideas, suggestions or contributions, do let us know! It will be greatly appreciated!

2014 Diary: Day 11 - A lesson learnt, is a lesson remembered

A special post by Nick Baglow and his group:

Today was a day of lessons. Some in the manual, some not:

Lesson 1 is fundamental, oft-repeated but temporarily forgotten in the enthusiasm of the moment: don’t wander into the desert without your water. Okay, not quite wandering, but that 10 minute foray up the little hill to check out the ‘simple’ quartz vein may turn out to be not quite that straightforward. Instead try 3 hours and returning to the vehicle with somewhat parched throats and more questions than answers. But at the same time you’re already planning what to do, where to look or who to speak to to solve the problem. Typical real life fieldwork scenario – great stuff!

Lesson 2 is also elementary in nature. Don’t get fixated on predicting what you are going to find as that’s a sure way of ensuring that some curveball will cross your path. Though today the curveballs were linear in nature with more than our fair share of thrust faults thrown in to repeat and remove stratigraphy almost at will. Fun, but not ideal when trying to learn stratigraphic principles perhaps!

Lesson 3 also fell into the unexpected category. Did you, for example, know that sticking a small square of paper on your forehead will end a bout of hiccups? Well now you do; it works, and much like with water-divining we just have to accept and move on….well, after much discussion that is, which contributed to the previously-mentioned 3 hour extended foray!

Clockwise from top left: Shane, Penester and Eveline clambering up the sheared basement granidiorites, curing hiccups at the mobile field clinic, no going back to camp until you all agree on the younging direction, and entering data into the field toughbooks at the last outcrop of the day

Tomorrow the lessons will be more formal as we head back to primary school; we're visiting the school in Kuboes to discuss stars, planets rocks and other exciting stuff J 

2014 Diary: Day 10 - First Day at School

Today the team split into smaller groups and started mapping individual areas across the Gariep Belt. All teams began within the Richtersveld National Park following the southern route along the Hellshoogte Pass. This road provides some interesting scenery straddling tall quartzitic and dolomitic lithologies. The Field School of 2014 has split the final portion of the Gariep Belt into several smaller sheets (approximately 5 X 6 km). It is envisioned that everybody within the team will have their own sheet to complete, however with geological data being shared across all completed sheets. With this, team members will aim to ensure and motivate their partners to collect the data of the highest quality (not knowing who might be providing the bulk of their data).

Today we follow the progress of Tebogo, Belinda and Haajiera. This team aimed to complete a section across Zone 20. Preliminary remote sensing suggested that this would be a relatively simple sheet, however it was anything but. This team started in a strange clast-supported diamictite (previously not seen by this group). This is highly foliated and coarse-grained (ca. 1-2 cm), with clasts of quartzite, arenite and dolomite. Of further interest was the presence of basaltic dykes cutting across, and being entrained within this unit. The dyke had phenocrysts of plagioclase, showing a strong mineral elongation lineation and in some places amygdaloidal texture. This unit bares remarkable similarities to the volcanics within the Vredefontein, however provided this group with a few things to consider: 1. If this was older (Vredefontein being older than the Numees/Kaigas), why does this show no foliation/evidence for strong deformation; 2. If this was younger, why are there also rafts of dyke entrained in the foliated diamicitite?

Clockwise: Basaltic dyke entrained and cutting across a highly sheared, clast-supported diamictite; Kaigas-proper dimictite and Numees-proper varved carbonaceous shale with dropstone; our team hard at work

Thereafter, they proceeded to climb some mountains and encountered the Wallekraal, within the Hilda Subgroup. This unit, similar to what was seen during day 2 of the show-and-tell displays both a bedding plane and foliation plane. This is possible due to the bedding being preserved at the contact between the carbonate and phyllite layers. Deformation was concentrated due to strain partitioning in the phyllite, thus forming a prominent foliation in this rock while the carbonate would simply recrystallise in response.

Further along, the group encountered Vioolsdrift basement rocks of this area. This mostly comprised of metavolcanics and granite-gneisses. The metavolcanics in particular displayed strain markers highlighting a top-to-the-west sense of shearing. There were also several large thrust faults, forming tectonic contacts with the Rosyntjieberg quartzites; and shear zones forming a prominent crenulation cleavage in places.

In total this group consolidated their knowledge of identifying and measuring structural elements expressed in the various lithologies, in addition to completing thorough rock descriptions and producing detailed field sheets. They will now look forward to sharing/learning from others tomorrow as the groups will continue to vary and complete the respective sheets.

Click here to see the mapping route of the group: Mapping 1

2014 Diary: Day 9 - Cooking the Kuboes

As temperatures increase, so too does the level of geological knowledge being exchanged during the field school. Today was the second part of the show-and-tell day and the team began by looking at the Kuboes pluton. This large (ca. 35 km wide) pluton formed during the Pan-African (ca. 507 Ma) after the closure of the Adamaster Ocean and the amalgamation of Gondwana. The team closely examined the minerals and did a mineral proportion analysis. Once in agreement, they plotted this on a QAP diagram. A QAP (quartz, alkali-feldspar, and plagioclase) provides a mechanism for accurately labelling intrusive/extrusive rocks. Based on their assessment, the team decided that the Kuboes is a quartz-bearing monzonite. In addition, they noticed the interesting Rapakivi texture. This texture is formed after the exsolution of plagioclase along the grain boundary of the alkali-feldspar.

Clockwise: Kuboes quartz-monzonite with Rapakivi texture; Numees tillite, Wallekraal phyllite-carbonate layers; Kaigas diamictite

The team then moved on and described the Numees formation tillite. This was of particular interest to the group following their visit to the Dwyka, near Laingsburg. The Numees displays well-preserved varved sediments with many exotic clasts and drop stones. The Numees was deposited during the Marinoan glaciation where most of the Earth was covered in ice. The Numees within the contact aureole with the Kuboes pluton (consider that the Kuboes would have been emplaced with temperatures up to ca. 1200 degrees Celcius) underwent contact metamorphism to upper hornfels conditions. This, together with large quantities of fluids passing through the Numees made it highly prospective for gold and fluorite, however no economically viable commodities was ever located. Deformation is clear in the Numees with the presence of numerous shear sense indicators (i.e. rotated porphyroblasts), highlighting top-to-the-east sense of direction. A sense of direction that highlights the regional thrust direction.

 The Pickelhaube (Hilda Subgroup) was thereafter investigated. This relates to a period when glacial conditions had subsided, allowing for the introduction of shallow-marine conditions. During this time the limestone of the Pickelhaube were deposited; characteristically showing elephant-skin weathering. There are also two particular variations within this unit, a lighter variety and darker variety. This highlights changes in the mineral chemistry and concentration of iron in these rocks.

 The Wallekraal (together with the Pickelhaube) also within the Hilda Subgroup was the final unit investigated today. This was of most interest to the team since it showed bedding and foliation planes. Here the team had an opportunity to test their abilities with the new Silva compasses and attempt measuring both these features.

In addition to the rocks, the team also visited the Primary School in the town of Kuboes, a short visit to deliver some posters. The team will return on Friday to continue the Richtersveld Science Day and continue a lecture series and workshop.

Some of the guys and girls in the field: Clockwise: Ndidi measuring lineation; note taking; sisters Belinda and Tebogo share a joke; Neo and Shane capturing data using the Geotac field computer

Tomorrow the team will split into smaller groups and start the mapping programme, under the supervision of our team of experts!

2014 Dairy: Day 7/8 - Home Sweet Home

Our arrival into the Richtersveld was marked by a lack in communications, namely no internet! Thus my inability to update our followers on the team’s progress over the last two days. I’m sure there were many worried people out there (family and friends), but I can assure everyone that the team is still alive and well, and we have not vanished into the wild!

Yesterday (Sunday 16 Nov) the team hit the road once more. As usual, they left promptly a few hours late and headed north toward Malmesbury; then onto the N7 toward Springbok. Along the route, the team followed the northern Limb of the Cape Fold Belt (showing very little signs of the impressive folding seen earlier along the eastern limb- why do you think this is the case?), starting along the rolling hills of the Malmesbury shales. These shales underlie the famous swarland (home of Weetbix) and a lot of the Cape Wine lands. After driving up the escarpment, near Pickenierskloof there was a drastic change in scenery as the geomorphology was dominated by a flat-lying terrain. This naturally makes the long drive seem even more arduous and never-ending, but respite was on offer near Springbok where the team entered majestic granite domes within the Okiep District. Springbok was a welcome relief where the team did some last minute shopping, realising that this is “lamb country” (no beef to many a dismay) and headed off the final destination, saying goodbye to the city life for a while.

Click here to download the route: Day 7

Eksteenfontein. Located on a major tectonic contact, of the Gariep and basement Vioolsdrift gneiss, Eksteenfontein was founded near the source of the Stinkfontein spring. Stinkfontein or “stink fountain”, referring to the sulphurous odour associated with the spring. This of course relates to the influence of the mineral chemistry after fluid-rock interactions beneath the spring, rendering the water hard, but drinkable. Eksteenfontein also formed the starting point of the Richtersveld Science Day/week. Today, the team watched in awe as Conrad lead a town hall meeting and lecture on Astronomy and the universe. This enthralled a large crowd at the Eksteenfontein community hall, most of which were avid star gazers already (since there’s nothing much else to do in Eksteenfontein). Simultaneously, there was a hand over of several posters and a short round table discussion with the teachers of the local primary school. Unfortunately, the lecture series intended for the school kids in Eksteenfontein had to put on hold due to the examinations having started. I was however told by several of the kids that “the exams are going okay…”

Clockwise: Nick at Nicky's, Conrad and Neo using some useful props to explain the solar system and some of the attendees at the Astronomy lecture

The Richtersveld Science Day/Week will most certainly be a major success. After today’s start, we have had several requests by the teachers to extend it to Alexander Bay and Steinkopf, including two of the large high schools. This is something we very much look forward to and will keep all duly informed. Do let us know if you’d like to be involved in any way!

Later in the day, the team then began the field introductory course. This was done while making their way to our field base in Sedelingsdrift, within the Richtersveld National Park. Here, the team was made familiar with the different rock types that they’ll be mapping and taught how to describe and measure structural/sedimentary indicators from these rocks. The temperature soared to 42 degrees Celsius, bringing new meaning to a warm welcome! The day saw the team covering the Stinkfontein Group and the Gannakouriep dykes. Paleocurrent directions, younging determination and measuring of forest beds all made up for a very successful day in the field.

It's getting hot in the kitchen: Some scenes of the show-and-tell day in the field

Tomorrow the Richtersveld Science Day/Week will continue to Kuboes with another town hall meeting and a visit to the local primary school. Once again, posters will be handed over and the team will have a chance to interact with the community. Something enjoyed and being looked forward to by all!

Some toys to play with-while getting structural measurements. Neo distributes brand new Silva Compasses to the team

View the day’s route here: Day 8

2014 Diary: Day 6 - Cape Peninsula

Unfortunately due to the inclement weather the original plan of hiking up Table Mountain was not possible, this of course saddened the team tremendously. So much that they seemed to refuse to wake up and get out of bed. This is surely signs of depression we thought, and thus had to make speedy alternative plans. None better than taking a drive across the Cape Peninsula to take in all the sites and perhaps a bit of geology along the way.

Muizenberg from the vantage point of the shark spotter. From here, a spotter sits and keeps a lookout for any sharks, and if seen, swimmers and surfers are called out of the surf

The Cape Peninsula is mostly made up of the Table Mountain Group. This includes the Peninsula Formation quartzites, which comprises most of the mountains around this region. The Peninsula Formation is further underlain by the Graafwater Formation shales. The latter is a highly fissile and an easily weathered unit; its inept ability to handle weathering results in many rock falls of the more weather resistant quartzites above! As was seen in along the Chapmans Peak Drive. The oldest unit in the Peninsula is the Namibian-aged Malmesbury shales. This makes up most of the underlying sediment in the Northern Suburbs, and is prominently exposed along Table Mountain, Lions Head and Signal Hill. Also very noticeable is the intrusion of the ca. 550 Ma Cape Granites, prominent especially while sunbathing on Camps Bay or Boulders Beach.

Nom Nom Nom- Kalkies Fish and Chips, and Calamari

The geology made our team very hungry and thus we went off to find the best fish and chips! Our hunt ended at Kalkies, in Kalk Bay where not only did the team get to enjoy a well-deserved lunch, but also play with a feisty seal and buy some little mementos from the fair Cape. One of the members was overheard saying: "I wish we could eat this everyday at the Canteen in Head Office..."

Eve and Nox striking a pose

Our “Big Deal” of the day was that it was Tebogo’s first day at the beach! She was understandable over-excited, so excited that she did not show any signs of the said excitement. Also, just too excited that she forgot to bring a bathing suit! Luckily, Nox was on hand to sweep her off her feet and almost throw her into the deep end of Fish Hoek! Tebogo was reported saying that: “I am very excited, it’s just that I don’t show it…” Maintaining the highest levels of modesty!

Tebogo's first day at the beach, keeping clear of the waves, way clear

Tomorrow the team is off again, this time to Eksteenfontein, prediction: Heat Wave…

2014 Diary: Day 5 - Remote Sensing

Remote Sensing 

Today the team spent the day with Dr Paul Macey from Mapping Geosciences (Western Cape) learning all about remote sensing techniques and how these are used to do preliminary investigations of their mapping areas. Dr Macey has substantial experience in geological mapping throughout Africa and the applications and uses of advanced remote sensing techniques to aid in the geological investigations.

Example of remote sensed ASTER imagery using various band ratio combinations to highlight possible variations in the geology. Typically different colours relate to different rock/soil chemistry

Remote Sensing stems from the manipulation of band ratio combinations of aerial imagery to delineate various geological units. The imagery is obtained from passive sources such as satellites or airborne photographic sensors, or active sensors such as radar or lasers. The material (e.g. rocks, soil, forestry, oceans) being captured by the sensors will absorb certain amount of light and reflect according to several factors, most notably, the chemistry of the material. Through the use of various band ration combinations, rocks high in certain chemistries will reflect a specific colour. Remote Sensing techniques can make estimations of what the chemistry of these different colours are and further relate that to possibly geological units. Through this mechanism, a preliminary geological polygon map can be created and be cross checked while performing field work. This is particularly useful once all different colour-coded polygon have been cross checked and can aid in the production of an accurate geological map if 100 % field coverage is not possible during the mapping.

2014 Diary: Day 4 - Duplexing

The team completed the first section of the Field School today as they travelled from the overnight stop of Laingsburg to Cape Town. They will now swap the nomadic lifestyle of uncovering the geology of South Africa for a short course on remote sensing, further preparation for looming field work and last, but not least, a closer look at the fairest Cape’s geology.

Our team of young intrepid geologists aligning and scrambling like crazy to see the Matjiesfontein Chert Bed (in lower left corner)  in the Laingsburg region

After having looked at the top of the Karoo on day 3 (e.g. in the Golden Gate Highlands National Park), the team had an opportunity to now investigate its lowermost successions. This was of major interest because some of these units include the highly prospective black carbonaceous shale. After scrambling to the top of one of the many hills around the Laingsburg region, the team had a look at the Matjiesfontein Chert bed. This ca. 60 cm chert bed forms a prominent marker horizon separating the White Hill from the overlying Collingham Formation. Below the Whitehill we found the Prince Albert. Together these three units share relatively high total organic carbon content, with the lions share going to the White Hill. The team further considered various aspects of structural geology at play, with the fissile black shale showing peculiar pencil cleavage planes. The intersection of these planes results in the shale breaking apart into needle-like splinters. Tiny crystal of the mineral pyrite was common in most of the black shale. This signifies the effect of sulphur-releasing bacteria assisting in deconstructing of organic material (i.e. plant and animals reducing in anoxic deep marine environments). The release sulphur would ultimately react with iron in the sediment and form pyrite.

After three days, the final stop within the Karoo Supergroup was symbolically, to the bottom Dwyka Group. The team initially thought that it looked very much like a volcanic rock of some sort, similar ideas shared with some of the first geologists who had interpreted this rock many years ago. However, the team would soon realise that the Dwyka was not volcanic, nor the result of cataclysmic meteorite impact, but rather deposited by a glacier. Polar wander theory would show that the South Pole was located near the location where the Dwyka would have been deposited, with global-scale ice sheets advancing and retreated, picking up foreign clasts from several thousand kilometres away; eventually forming the famous Dwyka Tillite. This was also of particular interest because in the Gariep the team will be seeing a similar tillite of different age. Several ice-ages?

Exquisite folding of within the Cape Fold Belt 

When one door closes, another opens, and behind the second door was the Cape Supergroup. There was no respite for the team as they were thrown into the deep end of classical structural geology. Driving south, along the Seweweekspoort Pass, the team entered the Witteberg (i.e. the topmost of the Cape Supergroup) and were once again totally awestruck by the level of deformation shown. As we continued south, and west toward Cape Town we were really treated to some of the best Alpine-style continental building demarking thrusting and immense folding along the way. The Cape Fold Belt (CFB) was formed as a consequence to the amalgamation of Gondwana. Of interest is the fact that the CFB is located more than 1000 km away from the continental margin, however strain was able to accumulate substantially enough to form the exceptionally large mountains seen. How would this have happened?

Kogmanskloof, now geoheritaged in the Western Cape

Within the CFB, the team noted several hot springs aligned major thrust faults. This provides evidence suggesting that this mountain belt has high heat flows. Groundwater aquifers are recharged from the high mountains and circulated by an intricate fault network. The groundwater is heated thanks to the effect of the Cape Granite. Being relatively young ca. 550 million years old, the granite provided a rich abundance of heat producing elements (i.e. uranium, thorium and potassium). These elements would slowly undergo radiogenic decay and emit heat. Heat, now enjoyed by thousands visiting the various spas in the southern Cape!

The team will now focus on the mapping to come. Tomorrow will be spent performing remote sensing and trying to delineate different potential geological units in the Gariep Field area prior to arriving there on Sunday.

Check out todays route here: Day 4 

2014 Diary: Day 3 - Great Karoo

Our team continued in their journey across South Africa today entering the Western Cape and also making a symbolic stop in the Eastern Cape. The night was short for most, but all remained very eager to get on the road and learn some geology. Our overnight stop was at the Gariep Dam, near the source of the Orange River. This is the largest water reservoir in South Africa, capable of storing more than 5 billion litres of water and covering an aerial extent of more than 370 cubic kilometres. Water from the Gariep Dam is also released into the Vanderkloof dam. The latter has 4 hydroelectricity generators capable of producing up to 360 MW of electricity when needed (which is most of the time these days).

 The Gariep-Vanderkloof dam and hydroelectricity plant

Today, the geology was completely dominated by the Beaufort Group. From the Gariep Dam, to Fraserburg the team was treated to various mudrock and sandstones of the Adelaide Subgroup. An extra treat was the witnessing of a Karoo flash-flood that caught the team by surprise. In an instant, all dry river beds were awash with raging torrents that devoured roads and everything in its path. In another instant, it was all over and blue skies and sunshine prevailed. It is worth noting here that the present day Karoo is very much an arid landscape, however more than 200 million years ago, this was a lush and fertile land similar to the today’s tropical regions.

Flash flood in the central Karoo

The highlight of the day was a visit to Fraserburg and the Gansfontein Paleosurface. This represents a pool-like environment where various creatures gathered and left remarkably many trace fossils for the team to ponder over. This paleosurface is located in the Abrahamskraal Formation within the Beaufort Group, a unit that covers the infamous Permian-Triassic (PT) boundary. Infamous of course, because this period in geological history relates to a major extinction event that resulted in approximately 90 % of life to be erased! Question: What are the possible causes for this extinction? Luckily, the Paleosurface at Gansfontein provides a memoir of some of these creatures. This most notably includes a mammal-like reptile, or tetrapod, known as a Bradysaurus, part of the Pareiasaur group. This is also thought to be an ancient ancestor to the modern day tortoise. This is based on similar morphology of the skull and evidence of bony plates that could be precursors of the tortoise shell. This was a herbivore that reached up to 3 metres long and weighed more than half a ton! For more information about the Gansfontein Paleosurface, click here to download a short report and detailed description: 1986_deBeer

Bradysaurus tracks on the Gansfontein Paleosurface

Reconstruction of Bradysaurus (http://en.m.wikipedia.org/wiki/Bradysaurus)

There are many other spectacularly exposed sedimentary features and arthropod trace fossils on this Paleosurface. This makes is something that is most definitely worth visiting that next time you're anywhere near Fraserburg. To visit the paleosurface, simply go to the Fraserburg Museum and ask and a guide will accompany you and show you around! Tomorrow the team can look forward to a trip across the Cape Fold Belt and consider elements of continental building and structural geology.

View the days route here: Day 3

2014 Diary: Day 2 - Solid Gold

As flashes of lightning and rumbles of thunder roars in the background, I can happily report that the team survived one of the longest days in field school history. The day began with unforeseen technical difficulties resulting in the need of a locksmith and a newly cut set of keys for one of our vehicles, the rest can be left to the imagination. Thereafter, we departed the overnight stop in Ermelo and continued over rolling hills of the Karoo (Stormberg Group) before entering Kwa-Zulu Natal and being warmly welcomed by numerous speed-cops (welcomed; nothing more I should add). Our stay in KZN was a short one, as we continued into the Free State and headed toward the Golden Gate Highlands National Park (www.sanparks.co.za/parks/golden_gate/).

The Golden Gate National Park is renowned for its majestic golden cliffs of the Clarens aeolian sandstone formations (upper Stormberg Group within the Karoo Supergroup). The team was left awestruck by the spectacular views and numerous photo opportunities.  The Clarens sandstone was deposited in a desert environment where large quantities of wind-blown sediments accumulated to form the iconic cliffs of this region. In addition, oxidation processes were common and resulted in an array of rust-stained colours spread over the cliffs. A close association was the emplacement of the Karoo Igneous Province. This was of course associated with the breakup of the Gondwana Supercontinent. This igneous province covered an area of more than 100,000 square kilometres and its start overlapped with the final stages of Clarens deposition. Because of this, the Clarens is often interlayered with layers of volcanic units, as well as cut by later dolerite intrusions.

Scenic views within the Golden Gate Highlands National Park

As lightning now strikes my abode and kills the electricity, I will sign off and look forward to a palaeontological-rich day 2. No further spoilers will be given, so be sure to check soon!  

To download the days route (kml) click here: Day 2

2014 Diary: Day 1 - Time Travel

"Lambs to the Slaughter" Field School group of 2014: from left to right: Taufeeq, Khaya, Haajierah, Nick, Ndidi, Tebogo, Nox, Belinda, Penester, Eveline, Neo, Olma, Ntsundeni, Shane, Conrad, Mpumelelo

The CGS Field School of 2014 officially began today! The team departed promptly (a few hours late) from the Council for Geoscience head office (Silverton, Pretoria). The route began on the N4 highway crossing vast sediments of the Pretoria Group (Transvaal Supergroup), before entering an expansive landscape dominated by the Permian Karoo Madzaringwe Formation. The highly prospective coal seams within this unit are evident with various coal mines along this route and moreover, the large coal-fired power plants, most notably around Emalahleni (Witbank). It is worth noting here that coal powers more than 85 % of South African electricity and forms a key export commodity. Some of this will be further discussed tomorrow, as the group enters the central Karoo Basin, where discussions will also include the highly contentious shale gas issue.

Neo couldn't believe that you can find stromatolites that are bigger than him

Before entering Nelspruit (Mbombela), the team followed a slight and tremendously scenic detour toward Sabie and viewed spectacular giant stromatolites within the Malmani dolomites. These ca. 2.75 Ga stromatolites display some of the earliest evidence of life on Earth, where cyanobacteria in a shallow marine environment slowly produced oxygen through processes highly similar to modern day photosynthesis. Chert and ferrigunous layers are closely associated with these giant stromatolites, what could this tell us about early Earth processes? Modern day stromatolites can be seen along Shark Bay, Australia (http://www.sharkbay.org/stromatolites.aspx). Interestingly enough, while these rocks host some of the earliest forms of life, they also host some of the earliest signs of human life, inhabited in the nearby Sudwala Caves (http://www.sudwalacaves.com/).

Barberton Mountain Land

The team then continued further into the past and entered the Archean! The trip from near Sabie to Nelspruit forms a much quicker and more efficient way of time-travel, than having to defy relativity and attempt to construct a time machine. This change is marked by a drastic change of scenery, from the enchanted forests of the Malmani, to the colossal boulders of the Nelspruit and Kaap Valley Tonalite batholiths. To unwind and understand the stories of the past, the team began the recently opened Barberton Makhonjwa Geotrail (http://www.geotrail.co.za/). The Barberton mountain lands is one of the most well preserved fragments of early crust and speaks volumes of how the early Earth would have been and functioned. The Geotrail now offers visitors, both geologist and non-geologist a special chance to learn about this period of the Earth’s history.

From left to right: Spectacular slump folding in ferruginous sediments; Conrad explaining paleocurrent direction in the white tidal sediments; Geological explanations handed to you on a plate...we break the interns in gently! (Watch this space for the real world once we hit the Richtersveld!)

Along the Geotrail the team was treated to a brilliantly designed outdoor museum that perfectly illustrates everything that’s special about Barberton and why this is one of South Africa’s most valuable piece of geological heritage. This begins and ends with various types of volcanic rock found within the ca. 3.4 Ga Onverwacht Group. This includes pillow lavas, lapilli tuffs and komatiites. What do these rocks tell us about the conditions of early Earth? Impressive banded iron formation outcrops of the Fig Tree and various sediments of the Moodies Group was also seen, including some of the earliest tidal sediments.

Top: Typical Barberton Makhonjwa Geotrail information board, lower left: Olma excited to observe pillow lavas that are twice her size, lower right: group, maintaining health and safety regulations, observe the white tidal sediments

Download the full route here (kml): Field School Day 1, the trip continues through Kwa-Zulu Natal and the Free State tomorrow!