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66

Has tuff found amongst the deposits at the Dinosaur National Monument? Yes. The most famous section of the rocks in Morrison Formation in Dinosaur National Monument, the Brushy Basin Member, is chock full of volcanic ash beds that have long since been converted to rock (1, 2, 3). It's also chock full of dinosaur fossils, which is what makes it so famous. ...


64

...but China only has 37% of the world's reserves Michael Karnerfors has provided evidence that China produces 95% of the world's rare earth elements. However, China does not hold that much of the world's reserves of such metals. The US Geological Survey mineral commodity summary for 2017 for rare earths gives China's 2016 rare earth's production at 105,...


56

I could not find any scientific evidence that the earth was once completely covered by water (not lava). However, Australian scientists have hypothesized that the land share on a planet 2.5 billion years ago was only 2-3%. If it is true, then the largest percentage of the Earth that was ocean is 98%. Also: According to the modern scientific views, the ocean ...


28

TL;DR The majority of the Earth's iron was around when the planet formed. Calculations of the mass deposited by subsequent impacts show that these impacts were comparatively insignificant in changing Earth's iron levels, making the claim false. Additionally, those impacts came from bodies originating within the Solar System - not around other stars. In the ...


24

The title of this 2011 paper pretty much answers the question by itself: Global risk of big earthquakes has not recently increased. (For the record: Peter M. Shearer and Philip B. Stark, doi: 10.1073/pnas.1118525109 PNAS January 17, 2012 vol. 109 no. 3 717-721) They noted that there had been an increase in large earthquakes in 2004-2011, and some other ...


23

The story is slightly less dramatic than it sounds. The runways themselves are not being "shifted" (i.e. construction crews getting out and laying tarmac), but just renamed and signposted. From a Livescience report Runways are designated according to the points on a compass, and the drifting magnetic north means that they, periodically, need to be ...


22

There is induced seismicity in Oklahoma. There were 623 earthquakes above magnitude 3.0 in 2016. Some of these have been much stronger than 3.0, including a 5.8 magnitude earthquake in September 2016. The induced earthquakes appear to have begun around 2009, and the problem has grown since then: However, according to the US Geological Survey and other ...


21

I've long thought this graphic gives a good idea of the issue The problem at an airport is variation in local magnetic declination, not the variation in location of the magnetic north pole. Due to local magnetic anomalies, magnetic compasses rarely point at any magnetic north pole. As others have noted, Runway naming is mostly based on local magnetic north ...


20

The paper that sparked the news story states in its conclusion: Considering the historical documents attesting the occurrence in the “Old Jerusalem” of a disastrous earthquake in 33 A.D., the authors assume that a seismic event with magnitude ranging from the 8th to the 9th degree in the Richter scale could have produced a thermal neutron flux of up to ...


19

To restate your question, How can we statistically describe the intervals between mega-volcano eruptions? Do they follow a particular probability distribution with known parameters? Can we use this to make any conclusions at all about Yellowstone? We know of three eruptions 2.1 million years ago (mya), 1.2 mya, and 0.64 mya. This is an interval of 900,000 ...


15

No, continental rocks are not the same as ocean floor. Continents are mostly made up of minerals like granite, which are lighter than ocean floor minerals like basalt (sima, short for Silicon/Magnesium). Continental material is mostly sial (short for Silicon/Aluminium) which is lighter. Partially molten mantle material is pushed up at mid-ocean ridges, ...


15

According to Essentials of Oceanography (2012) at page 13 The physical expanse and distribution of the early ocean is a matter of some controversy. Most researchers hold that masses of rock have always protruded through the ocean surface to form continents. However, some recent studies suggest that water may have covered Earth's entire surface for some ...


13

China holds 95% of the world production of Rare-earth Elements When the letter says... The rare metals [...]. More than 85% of the world’s supply comes from China ...I believe the author means Rare-earth Elements/Rare-earth Metals. REMs are necessary elements in the production of electronics, computer chips of all kinds, computer/phone displays, solar ...


13

The mass of the Earth is approximately 5.98×10²⁴ kg. In bulk, by mass, it is composed mostly of iron (32.1%), oxygen (30.1%), silicon (15.1%), magnesium (13.9%), sulfur (2.9%), nickel (1.8%), calcium (1.5%), and aluminium (1.4%); with the remaining 1.2% consisting of trace amounts of other elements. Source: Abundance of the chemical elements The proto-...


12

In addition to @hdhondt's answer (+1) The evidence for the existence of Pangea lies in the existence of matches between fossil records and rock formations in continents that are now thousands of miles apart, in addition to Wegener's observation that the (continental shelves) of the existing continents match quite closely like a jigsaw. If Pangea did not ...


12

I cannot confirm the numbers in the original image, although some of the recent numbers appear to be roughly consistent with USGS numbers. However, the general point seems to be correct: the number of earthquakes has been increasing per year. But, the pastor is not correct: the number of "great" earthquakes is not increasing (see the response by ...


12

No, lithium scarcity is not a barrier to the take-up of electric vehicles. From Bloomberg: The world’s largest untapped lithium reserve -- containing enough of the lightest metal to make batteries for more than 4.8 billion electric cars ... according to the U.S. Geological Survey.


11

The claimed air density is about 520 times higher than air denisty now. This means that, according to the ideal gas law, you need 520 times the air pressure - roughly 520 bar. Now the critical point of nitrogen (main consituent of air) is about 33bar, the critical point of oxygen about 50 bar. Both critical temperatures are far below 0°C. So at this density,...


10

Upon closer inspection, such claims appear to actually state that diamonds cost more than their abundance alone would account for. Sources that outright claim that diamonds are common don't seem to have anything to back it up with. In terms of where diamonds can be found, this is true. Note that I believe a comparison of diamond production to gold ...


10

Esker has no evidence to support the idea of the Earths atmosphere being more dense in the Jurrasic than it is now, other than the assertion that dinosaurs are too large to have existed otherwise. However this assertion has little support, as evolutionary adaptions (such as the unidirectional breathing discussed in the previous question) are able to explain ...


10

Yes, some of them clearly were, for example whale fossils have been found in the Sahara at the Wadi al-Hitan. However, while some deserts were once oceans/seas, that doesn't mean all deserts were once oceans.


10

Based on an CNBC piece with similar claims, the Guardian letter seems to be talking about cobalt: For example, China controls 80 percent of the market in chemical cobalt, a crucial ingredient in lithium-ion batteries, [Benchmark Mineral Intelligence analyst Caspar Rawles] he said. Oddly enough a techcruch piece is somewhat contradictory Approximately ...


10

Nuclear fusion is the mechanism by which most atom nucleii have been formed from the original plasma present after the Big Bang. It requires incredibly hot temperatures not found in outer space. Since the Big Bang, nucleii have been formed in stars and then ejected in outer space at the end of the life of those stars. See for instance: Nasa's Cosmicopia ...


9

By the very definition offered in the article: Geo means Earth and Patho means suffering. It means suffering from the earth which causes stress in the form of illness. The Earth has no nervous system and is not scientifically known to suffer, although we can certainly imagine it doing so. That's a feature of human psychology, which is what this boils ...


8

There wasn't initially a problem with the Oxygen being released as the quantity of Iron on earth reacted with the Oxygen forming Fe2+ and Fe3+ compounds first. Only once all the available Iron had reacted with Oxygen did the Oxygen start building up in the atmosphere, but the rate of Oxygen production from all the Cyanobacteria on the planet by that stage ...


8

The original paper1 explains how the prints were dated: Here we report on a footprint surface found in Early Pleistocene estuarine muds at Happisburgh, UK, [...] The estuarine sediments at Happisburgh are part of the Hill House Formation (HHF) and are Early Pleistocene in age, dating to between 1 and 0.78 My. In other words, the footprints were made in ...


8

Here is a paper which was written to refute Gentry's theory: "Polonium Haloes" Refuted A Review of "Radioactive Halos in a Radio-Chronological and Cosmological Perspective" by Robert V. Gentry by Thomas A. Baillieul Copyright © 2001-2005 [Last Updated: April 22, 2005] It introduces rocks as follows. About the Rocks Geologists classify ...


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