![]() Spotting fossils can be easy in some cases where the bones are a distinctive texture and colour compared to the surrounding rocks, but this is not always so and there are many things that look like bone and are not. Apart from the GPS it is all extremely low tech. This is one reason why researchers keep going back to the same sites, not only can it take years to excavate large specimens but there are new things available to find each trip. If the rocks and soils are eroding, then buried bones will come to the surface where they can be found – searching in areas where there is little or no erosion will never reveal anything new. Hunts are also focussed on regions of high erosion. Entire formations can be traced for hundreds of kilometres to find new areas to look for specimens and of course areas that have been productive before are likely to be so again. Dinosaurs do turn up in marine sediments occasionally but there’s generally little point hunting for them in rock laid down in the sea. Palaeontologists do not just roam around at random but obviously start with areas that are geologically of the correct age and rock type to hold the fossils we are looking for. Such a process may be low tech (or even no-tech, for some finds you don’t even need a geological hammer) though these days a GPS kit is pretty much standard. If you find something good then great, and if it needs a bit of digging to see the condition of the specimen or identify what it is, well that’s not big hardship and you are unlikely to waste days or months making a huge hole to find that there are a lot of bones correctly detected with your radar, but they are in too poor condition to collect. ![]() Looking for fossils on the surface, or ideally, just starting to erode out of the ground is quick and effective. In contrast the traditional methods still do well. There’s also a pure practicality aspect – you might detect a fossil deep underground but it’s not going to be worth the huge time and effort to excavate a giant hole to reach it (compared to something that is at or near the surface) not least when there is still a risk it will turn out to be something of no great interest. An expert fossil hunter can cover far more ground far more effectively than most of these machines and can get to areas up hills or in valleys that machines cannot. The costs in time, effort and money massively outweigh the benefits. Given that most of the best fossil hunting sites are in remote and inaccessible places like Badlands and deserts, taking machines like this out fossil hunting becomes a real issue. They also work only fairly locally, covering a small area at a time. These are expensive machines that can be large and unwieldy, require electricity and might need skilled technicians to use them or interpret the data. In both cases though there are further fundamental issues. This is in poor shape but it marks an area worth exploring. But this only works for relatively large bones that are near the surface which are also radioactive.Ī shattered pterosaur wing bone on a slope. In the right circumstances, fossils can have a higher level of radioactivity than the background levels and bones can be found. Similarly, some bones have been found with Geiger counters. You could do a lot of digging to find nothing more than a rock or a cavity in the ground. Moreover, fossils are often small and so a level of resolution is required that cannot normally be produced and there are plenty of variations and quirks to local geology that could throw up false negatives. ![]() Ground penetrating radar has been used, but the fundamental problem is that fossil bones are generally of very similar densities to the rocks in which they sit, so getting a measurable difference between them which would show you where to dig is difficult. A number of technologically driven techniques have been developed to try and improve the process, but they have had limited success and the rewards have not outweighed costs.
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