Geology news

New Zealand earthquake

At http://phys.org/print398327283.html ... is about the threat of tsunamis from earthquakes while at http://phys.org/print398327221.html ... the focus is on the earthquake itself, magnitude 7.5 - and a plate boundary situation is being blamed (and the inevitable subduction zone). However, it was not as simple as that it would seem as lateral slop on a strike-slip fault is also involved - and a thrusting within the Pacific plate (close to the epicentre). In other words the epicentre of the earthquake was not at the plate boundary (or a subduction zone).

Australia on the Move

At http://phys.org/print398016399.html ... Australia shifts and tilts back and forth by several millimetres each year because of changes to the Earth's centre of mass (Journal of Geophysical Research, Nov 2016). Measuring millimetres must be subject to some scepticism but presumably it involves GPS. The centre of mass is thought to be in the core but what is it they think causes changes - ice and water during winter months.

proving subduction is ...

Presumably the theory of subduction (plates sliding beneath other plates and causing mountains to form) is still a theory - and has not been verified (or observed) which is why it has now received the modelling treatment in earnest. A paper in Nature Geoscience (Nov 2016) seeks to show carbon in the Mantle is derived from subducted crust - see http://phys.org/print397921452.html

Magma Lake

At www.dailygalaxy.com/my_weblog/2016/11/colossal-body-of-magma-discovered-... ... Scientists have discovered the existence of a huge magmatic lake (composed of magma and water) 15km across below a dormant volcano in Bolivia. The body of water, which is dissolved into partially molten rock at a temperature of 1000 degrees celsius is comparable in size to some of the world's biggest lakes on the surface. The water may go some way to explain how and why volcanoes erupt - if water is commonly found beneath volcanoes.

Fossil Trees

Fossilised wood from trees, such as branches, twigs, stumps, broken trunks, and all manner of pieces of woody material which even include whole woodland floor flora are fairly common in the geological record. At www.mining.com/50-million-year-old-tree-fossil-found-in-canadian-diamond... ... where we have a stump of a giant redwood tree found in a diamond mine in the North West Territories of northern Canada. It is fossilised redwood - a tree that now grows in California. It illustrates perfectly the manner in which climate has moved across the globe, from one epoch to the next.

Altiplano Uplift

The topography of the central Andes is the subject at http://phys.org/print396589441.html ... geologists have been investigating why so much uplift has occurred in that region since the end of the Pleistocene - uplift on a scale contrary to the mainstream consensus regards how long these processes take. For example, it is widely recognised that  Lake Titicaca was a coastal lagoon but now it is elevated at several thousand feet.

missing crust

At www.dailymail.co.uk/sciencetech/article-3824268/Mystery-missing-Earth-cr... ... (link provided by Gary Gilligan), an interesting article that can also be found at http://phys.org/print394869722.html ... in which University of Chicago geoscientists have concluded that half the original mass of India and a large portion of Euroasia must have disappeared into the earth's interior before the two continents began their slow motion collision 60 million years ago that led to the uplift of the Himalayas.

scotland asteroid strike

This one is geology rather than catastrophism as a geologist is at the heart of the discovery. Channel 4 Had a TV programme about it last week which you can see if you missed it at www.channel4.com/programmes/walking-through-time ... (and see also https://toriherridge.com/2016/09/23/walking-through-time-scotlands-lost-...

fossils in clay

Clays are formed by water action. You can say it is meltwater from draining ice sheets or tsunami like waves pouring over the surface of the earth (usually via river valleys). The exact interpretation is not easy to resolve but it is increasingly clear that in the Pleistocene there was a succession of watery events in some locations (especially at the bottom of ice sheets). Melt waters from the last Ice Age played a significant role in the levels of the Black Sea - and presumably the Caspian Sea also. It reached these locations by water flow along river valleys - such as the Danube.

Reef gets bigger

At http://phys.org/print391425744.html ... the Great Barrrier Reef has grown in size due to findings by the Australian Navy. They have discovered a massive extension of the reef that exists behind the more visible Great Barrier Reef that is seen by the public at large - on the deeper sea floor. Enviros worried about the reef being in its death throes were recently shut up for a while by a survey which showed only a very small percentage of the reef is damaged by bleaching (which appears to be a recurring natural process and nothing to do with human activity).