Geology news

oceanic crust

Most oceanic crust is thought to be no more than 200 million years of age. This is necessary if Plate Tectonics is a reality, the idea being that oceanic crust is continually being subducted under newly created sea floors. The idea of course assumes the planet has always been the same size as it is now in spite of the universe expanding and gas planets expanding and all kinds of other things in the universe expanding.

Yellowstone Biggy

Jovan Kesic has come up trumps again. He provides the link to www.scientificamerican.com/article/yellowstone-s-supervolcano-gets-a-lid/ ... simmering beneath the hot springs and geysers it is claimed lurks a dormant volcano.

Ancient Tsunami

At http://phys.org/print390032709.html .... work on the M4/M5 junction just outside Bristol (south Gloucestershire) has revealed a couple of bone beds going back 200 million years ago. A Kentucky undergraduate at the University of Worcester analysed samples taken 25 years ago (when the motorway junction was built or upgraded) and she has discovered they were not caused by a single flooding event, as previously deduced, but by more than one transgression event.

Wren Problem

At http://phys.org/print388832074.html ... a DNA analysis of living and extinct species of New Zealand wrens have upset geological theories as it has been claimed New Zealand was completely submerged around 21 to 25 million years ago. It is thought the various species are only distantly related and ancestry may go back prior to 25 million years ago. This is using a uniformitarian time scale of geology and a uniformitarian time scale of evolutionary change.

Greenland's Rivers

   Under the Greenland glacier radar has revealed a web of canyons caused by former rivers. Live Science provided the image on the left and scientists are saying the rives go back over 3 million years ago, when glaciation is thought to have set in. There are of course problems with this idea as the canyons are V shaped (which is why they are attributed to rivers and streams rather than ice melt or glaciers that carve out a U shaped valley).

Plate Tectonics

At http://phys.org/print386928085.html ... in 1966 J Tuzo Wilson published 'Did the Atlantic Close and Reopen?' in the journal Nature, introducing geologists to the idea continents and oceans are in constant motion across the surface of the Earth. This idea became known as Plate Tectonics - a sort of halfway house between the idea of continental drift as espoused by Alfred Wegener and the idea of rigid continents. It ws used to explain earthquakes and mountain building, a sort of all things for everyone, addressing a number of controversies in one fell swoop.

Dinosaur Movements

Scientists at Leeds University used computer modelling of the fossil record to work out the movements of dinosaurs. They used a palaeobiology database to work out migration patterns and it seems in the early Cretaceous period they found evidence (declining fossil numbers and varieties) in Europe and the inference is they were moving out of Europe to elsewhere in the world.

not up to scratch

The alternative geological journal New Concepts in Global Tectonics has some exciting stuff to read. The latest issue can be downloaded at www.ncgt.org/newsletter.php and one article is highly critical of Plate Tectonics. Has it served its purpose, and is it now out of date and due for retirement? It seems a study of dinosaur migration patterns reveal possible land bridges that don't really fit into the Plate Tectonics paradigm. This appears to be a new angle for mavericks to attack mainstream - and may have some traction.

Sand Rippler

At http://phys.org/print386572617.html ... Curiosity Rover has been looking at samples of sand and at sand dunes and presumably sandstones on Mars. A paper in the journal Science (this week) notes that some of these ripples are sinuous and resemble sand ripples that form under moving water on Earth (as you might encounter paddling in the tidal water at the sea side). Superimposed on these larger ripples are ripples the same size and shape as impact ripples on Earth - caused by the wind etc.

water on Mars

The water on Mars story is getting interesting. Is this another example of water as part of planetary make-up (even perhaps subterrranean water) (see post yesterday on Primary Water). Some interesting information is being beamed back to earth from Curiosity Rover on Mars, as it probes and analyses rock samples on the red planet. It has found manganese oxide in Martian rocks and scientists say this suggests the planet once had higher levels of oxygen (in order to facilitate the process of oxidisation).