New answers tagged geology
0
The oldest radioactive dating is uranium lead quantities and zircon. Oceanic fossils and minerals give us a estimate of height of primitive oceans. And the oxide mineral contents of geologic strata give us estimate of how much carbon and oxygen were in our primitive atmosphere.
2
I know a young geologist using his smartphone as a compass. When we were in the field doing structural measurements together, I would:
Record a waypoint using my hiking GPS
Take the measurement with my compass
Write it all down in my field notebook
Given the time to take all the things out, and put them away afterwards, it was at least 2$-$3 minutes per ...
-3
Unknown, namely because most scientists in "Earth science" related spectrum largely work in the public sector i.e. tax payer funded research (museums, smithsonian, various universities, USGS, etc) hense bias to human anthropological warming tends to be "Yay". You don't receieve funding for a circumstance you don't take as inherently ...
0
Take a look at the work of John Valley at the University of Wisconsin. He has dated zircons from the Jack Hills in Australia. Now, he is analyzing glassy inclusions in zircons. The inclusions are unaltered siliceous magma that formed the crust of the early earth. The American Geophysical Union published a volume of papers you should see. The book "...
2
Part of the answer lies in where the geologist will be working and if there will be coverage by cellular/mobile telephone networks.
It is my experience that a number of geologists, particularly exploration geologists, may work in remote regions where there is are no cellular/mobile telephone networks - parts of Africa, central Asia, Australia, South America, ...
1
To begin with, the formation of the Himalayas was never volcanic which is why you don't find volcanic rocks in the Himalayas. As for the subducting Indian oceanic plate (which contained Indian continental crust) that volcanism can be found in Tibet and the eastern Himalayas, in far northern Myanmar. This would suggest an oblique component to the subduction ...
4
We don't know for sure because A. the evidence has almost all been erased by the continued crustal shortening of the area where the volcanic arc(s) would have been. B. the region is huge and volcanism will have varied in duration greatly across the range as a whole. The "core range" of the Himalaya has lost on the order of 6000km (~2500 miles) of ...
1
For dating old geological material, zircon dating is sometimes used. Also see Uranium-lead dating. There is also data from Antarctic and Greenland ice cores.
Other things you could look are Earth formation theories - the core accretion model & the disk instability model as well as plate tectonics and continental drift.
There are also the theories about ...
1
From the readme.doc file, it looks that 1, 2 and 3 following AF and the other soil symbols in the excel files you mention are about this:
Texture classes reflect the relative proportions of clay (fraction
less than 0.002mm), silt (0.002 - 0.05mm) and sand (0.05 - 2mm) in the
soil. Three textural classes are recognized: coarse (1): sands, loamy
sands and ...
0
They might be looking at the problem backward. It is now believed that new world monkeys are the descendants of old world monkeys that floated on mats of trees across a much narrower Atlantic tens of millions of years ago. Even then, the Atlantic was much wider than any gap in the Indonesian area. So Borneo is an exception in that it has a marsupial, the ...
Top 50 recent answers are included