Monthly Archives: September 2017
Volcanism and sea level fall
If there were decompression melting of magma in the West Antarctic volcanic province as the icesheet thinned, that would not be good news.
If the geological Society link in the article doesn’t work for you, try this one; http://sp.lyellcollection.org/content/early/2017/05/26/SP461.7
Most volcanic activity stems from the rise of hot, deep rock, usually within the mantle. Pressure suppresses partial melting, so as hot rock rises the greater the chance that it will begin to melt without any rise in its temperature. That is the reason why mantle plumes are associated with many volcanic centres within plates. Extension at oceanic ridges allows upper mantle to rise in linear belts below rift systems giving rise to shallow partial melting, mid-ocean ridge basalts and sea-floor spreading. These aren’t the only processes that can reduce pressure to induce such decompression melting; any means of uplift will do, provided the rate of uplift exceeds the rate of cooling at depth. As well as tectonic uplift and erosion, melting of thick ice sheets and major falls in sea level may result in unloading of the lithosphere.
During Messinian Stage of the late Miocene up to 3 km…
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Is a good science talk really a bad science talk?
Engagement, suspense, and dramatic denouement; I wish someone had told me the importance of these at the beginning of my career, instead of leaving me to discover it half way through
One of the mantras drilled into the heads of graduate students as they prepare their oral meeting presentations is “tell them what you are going to tell them, then tell them, then tell them what you told them.” The point being to make sure that the audience knows what you think is important. And at a meeting, this can be pretty significant as folks wander in and out of a room or are distracted. That first part tells them what they should really look for (and it helps to remind the student what they are emphasizing), the last is to reaffirm that the desired goal was in fact met.
But this is probably a lousy format for a colloquium talk and even lousier for a public talk. Think of the storytellers out there and how their stories go. Does Hans Christian Anderson tell you what happens to the Little Mermaid…
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What do Christians really believe about evolution?
Most people in the UK think that religious people believe in six-day creationism. Fortunately, they are wrong.
Less than one in six UK believers prefer separate creation to evolutionA new YouGov poll conducted in Canada and the UK shows two contrasting facts. Among those who call themselves “believers or spiritual”, only 16%, under one in six, rejected evolution in favour of separate creation. A much larger group (39%) thught that “Humans and other living things evolved over time, in a process guided by God”. As an advocate of evolution science, I regard such people as potential allies. “Guided by God” is so vague an expression that it could be taken to include God having set up the laws of nature, which was actually Darwin’s own position, according to his autobiography (here, pp 92-3), when he wrote Origin of Species. (Caveat: the options offered were
- Humans and other living things were created by God and have always existed in their current form
- Humans and other living things evolved over time, in a process guided by God
- Humans and other living things evolved over time as a result of natural selection, in which God played no part
- I have another view of the origin of species and development of life on Earth which isn’t included in this list
- I don’t know / I do not have a view on the origin of species and the development of life on Earth