Tags: science

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 […]

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Borehole Grapher/Mapper

As part of AEON‘s baseline study in the Karoo, a group of my colleagues are undertaking a large scale hydrocensus in the area near the Western Cape/Eastern Cape boundary. At the moment, this entails visiting a large number of boreholes, recording some general information about them, and, where possible, recording the electro-conductivity of the borehole. They are also going to be doing other tests. The ultimate goal of this is to narrow down which boreholes we will be monitoring on a recurring basis. This has lead to a large amount of readings, associated with a given depth, being recorded. Excel is painful to use, because there is no consistency in the depth of boreholes, so while some tests may only have 20 readings, there is one with nearly 300. This precludes automated graphing in Excel. So, I have written a Python script to do this for me (mostly as practice, but hey, this will be pretty useful for the people actually working on it). I got this working adequately, and then realised that since I have coördinates for each borehole, I could graph the results. Looking around, I settled on leaflet.js to do the mapping part of it. As such, […]

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But we already have that: Nature’s link sharing

There has been much written recently about Nature’s new link-sharing initiative. I am not going to go in depth into how it works, but essentially this allows for the sharing for links by people who already have access to them to those without access. A good summary, with links to numerous other posts (none of which are overly positive) has been written by Jon Tennant. As a friend[1] put it when I described it: “But we already have that”. And that is one of the problems that I have with this. It is not a major step forward. You still need to get a link from someone with access. The only difference is that this is officially sanctioned by the publisher, and can be tracked by them, unlike emailing the author or getting it from a friend. (Cue sarcastic “thank you for letting us share our own research, paid for with government money, for people not lucky enough to have a subscription”?) The addition of some news outlets in the list of people who can generate links is a good move, in my opinion, which I will talk about later. However, why should people need to ask for a link? […]

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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.

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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 […]

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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 […]

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