Geology news

bone beds

Bone beds. What are they? It is rare to come across a complete dinosaur skeleton - or even a partial skeleton. These are what scientists like which is why the recent discoveries in China and Argentina have taken such a prominent position in various pieces of research in journals etc. The media of course also like dinosaur skeletons and most of us have been impressed by specimens in natural history museums.

Olivine

At http://phys.org/print400858229.html .... apparently, ocean bottom crust in the modern world is thinner than it was prior to the break up of the supercontinent of Pangea. Plate tectonics has subsequently caused the crust to cool and at the same time thin it. All that heat and plate activity after  170 million years ago is being blamed for a thicker ocean floor crust at that time. The study involves computer modelling.

Atacama

This is the second time we have had a post on the Atacama desert in Chile. In this post we learn that the desert hosted lakes during the last Ice Age and these may have survived long enough to provide sustenance for humans in their journey from NE Asia to the tip of South America. See http://phys.org/print400939325.html

Sea Level change

In the journal Geology (28th July 2015) doi:10.1130/G36914.1 ... there is an article that seeks to establish a synchronicity in key Holocene chronologies by extracting evidence from Irish bog pines - by Max Torbenson, et al. (a collaboration between scientists from Queens University in Belfast, Gottingen in Germany and the University of Alabama). It was described as an opportunity to test the stability of the Greenland Ice Cor chronology against IntCa (C14 calibration curve) and the idea was to see if there was any corresponding evidence of the 6200BC event.

Roger Higgs

Roger Higgs featured at the Geological Society of America annual meeting in Denver (2016) a few weeks ago, and presented a paper that claimed there was historic evidence for a 5m rise in global sea levels in the Late Roman/early Saxon era. Higgs, who lives in Bude, famous for its surfers on the north Cornish coast, runs his own company and is a busy man, as they say. At face value this idea would seem to support the climate change position as the inference is that the Roman Warm period was responsible for the rapid and steep rise in sea levels (at least around Britain).

Ghawar

At http://phys.org/print399653135.html ... the origin of Saudi Arabia's Ghawar giant oil field is the subject of this link. It would take a massive amount of vegetation to be transformed into the massive oil field - virtually dense tropical vegetation. Plate Tectonics doesn't seem to be the answer. It is too slow. The vegetation must have been converted much more quickly - or this is the thrust of the article. Of course, quickly in geological terms is nothing like instantaneous - but reading between the lines we may wonder why not.

Caribbean Sea Change

At http://phys.org/print399180551.html ... scientists looking at the K/T boundary crater off the coast of Yucatan have discovered it was dry land at the height of the Late Glacial Maximum, between 23,000 and 18,000 years ago. How can this be? The obvious mainstream answer is that a lot of ocean water was locked up in the hypothetical ice sheet that covered a great deal of the northern hemisphere. An outside the box answer might involve a change in the earth's geoid - but that would require a rise in sea levels somewhere else.

NZ Earthquake

At https://tallbloke.wordpress.com/2016/11/19/new-zealand-quake-ruptured-6-... ... the recent earthquake in New Zealand affected up to six faults - and uplifted significant portions of coastal New Zealand

   During the earthquake bystanders took images on their cell phones of earthquake lights (see www.livescience.com/56869-what-are-earthquake-lights.html)

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.