Tags: geology

AfricaArray Geophysical Field School – Day 1, Vredefort Dome

I am currently attending the AfricaArray field school, hosted by [http://wits.ac.za](Wits University). The first day was a relaxed one to allow for the international students to recover from jetlag. Accordingly, we wandered off to visit the Vredefort Dome. This is one of the largest, and the oldest impact structures in the world, so we are very lucky that we can wander around it. It is also a UNESCO world heritage site. This is a world famous site and it was good to get an over view of the area. We started by getting an overview of the area, and the basic geology. Some of the most significant evidence is the presence of pseudotachylite within the basement granites of the Witwatersrand Basin. These formed under frictional melting due to the impact causing nearby rocks to move extremely rapidly. These are spectacularly exposed in some of the quarries in the area: These quarries are abandoned now, since the current fashion is for the use of very fine-grained, black facing stone, rather than textured rock. After that, we stopped next to the Vaal River for lunch, which was pretty idyllic. The work did not stop, since we worked out that the quartzite rocks […]


New Adventures

And breaking the silence. So, most people who know me as someone not on the other side of a computer screen (and even many of those) know that I recently relocated to Port Elizabeth. Why? Well, I am starting my MSc. The project is an interesting mix of computer science and geology, in which I will be processing a variety of geophysical datasets to provide baseline geological information on basin architecture. Settling in has gone well, and I am currently eyeing the rapidly growing pile of readings I have accumulated and need to sift through. The variety of subfields that I need to assimilate and synthesise is rather daunting, but, we shall overcome. I hope to keep this blog at least vaguely up-to-date on my progress, but it will take a bit of time until I have anything concrete to show.


Open South African Geological Data

In the last couple of years, I have had a growing interest in the open data and open access movement. I have not really done too much yet, being located on the periphery of what might be done, and with a lack of a specific project/problem to tackle. That said, I think that I have found one: Open geological data in South Africa. I have a vested interest in being able to use geological data freely, most regularly useful for me would be a digital map of the boundaries between different rock units as found on geological maps. Since a large portion of South Africa’s economy is reliant directly on mineral resources, it makes sense to have information pertaining to it to be available. While lithological data is available, much of it is at too high a scale to be very useful for looking at specific sites. 1:1 000 000 scale data is available, provided that you have a log-in at ESRI and can run ArcReader. That information can be found from this page. The link to the more detailed 1:250 000 scale maps is broken. The people responsible for collecting this data in South Africa are the Council for […]


Why Dinosaurs?

This may be a bit of a whiny post, but I am wondering about the prevalence of dinosaurs as the archtypical fossils. I mean, many small boys who have no inclination to learning anything can still rattle off a string of dinosaur names. Or at least they could when I was one. But why dinosaurs? They are not the only interesting fossilised things. Trilobites seem to be common, especially as tattoos, but beyond that there seems to be little variety. Why does no one talk about therapsids in the press? Why are pterosaurs and pre-dinosaurs like dimetrodon considered dinosaurs by many? Why are the many different non-dinosaur marine reptiles considered dinosaurs (mosasaurs, plesiosaurs, icthyosaurs &c)? I suspect part of it is due to the majority of US fossils (that I have heard of at least, feel free to correct me) being dinosaurs. This, combined with movies such as the Jurassic Park franchise, have brought them to the fore when considering fossils, in the same way as the dodo is the archtypical extinct animal due to direct human causes. In addition, there are some amazing fossils coming out of the fine-grained Jurassic- and Cretaceous-aged limestones that other fossils just can not hold […]


Where on Google Earth #355

Where on Google Earth is this?

Since I was able to locate the brilliant blue waters of the Bahamas in Felix Bossert’s #354, it falls to me to give you somewhere to look for. As a newcomer, I have chosen something quite (very?) easy, but apparently the pace of the game is slow right now, so the Schott Rule is not in effect. Where is this:  This should be a quick game, so good luck. EDIT: (2012-09-30) It appears that my judgement was off, so here is a bit of a hint: This is found on the edge of a major structure in the southern hemisphere. EDIT2: (2012-10-07) The structure is in Africa. It is easily found using your favourite search-engine, should you know what to search for.


Geology on the Interwebses

I have been upping the number of people I am following on Twitter recently. This has a bit of a snowball effect, in that following more people brings the people that they follow into your view and you start following them. The vast majority of people I have followed in the last few weeks have been scientists, specifically geologists/palæontologists/earth scientists or societies for them. While this is good, in that I genuinely find this stuff interesting, it also brings home how little I am keeping up with the field. What I do find worthwhile is that I am able to hear about interesting stuff, like Where on (Google) Earth. WoGE is a bit of a puzzle/treasure hunt, wherein an image (or images) of a geologically interesting place are posted and the first person to respond with the coördinates of the place shown (and something about the geology) posts the next image. Another, vaguely related, event is the Accretionary Wedge, whereby a number of bloggers within the earth sciences write on a particular theme each month. The range of views is an interesting overview on just how broad the earth sciences are: you get geophysicists, geologists, climatologists, palæontologists, planetary ecologists…. In […]