Chesapeake Bay Impact Crater(en.wikipedia.org)
en.wikipedia.org
Chesapeake Bay Impact Crater
http://en.wikipedia.org/wiki/Chesapeake_Bay_impact_crater
25 comments
It amazes me that these events seem "frequent" when you look at them overall, but then extremely rare when you realise how far apart some of them are (millions and millions of years). It really makes you realise just how small a window of time human existence has been given. We may see one or two major geological events in all of human histroy if we're lucky (or unlucky, depending on what they are!).
Not wishing to be a smart-arse, but I can't think of any major geological event that we would consider ourselves lucky to observe.
I bet many geologists would consider themselves lucky to observe some major geological events. Just as long as it's safe enough for their person.
The problem with the really big geological events is that they have no safe observation distance anywhere on Earth.
I mean, I'd love to see a 3 mile asteroid strike the Earth, just for the sake of observing so many cascading disaster effects...... so long as I could do it from space, while viewing an alternate version of the Earth, in which I don't have to live afterwards.
I mean, I'd love to see a 3 mile asteroid strike the Earth, just for the sake of observing so many cascading disaster effects...... so long as I could do it from space, while viewing an alternate version of the Earth, in which I don't have to live afterwards.
Fair enough. Maybe it depends on the definition of "major"
[deleted]
Debris from the impact made it all the way to Texas! https://en.wikipedia.org/wiki/Bediasite
I live just along the outer rim area. What’s amazing is that I have yet to run into anyone in this area who knows about the crater structure beneath their feet!
This may have contributed to the immiseration and decline of the Jamestown colony, some thirty-five million years later:
"Chesapeake Bay is the remains of a giant meteor crater. The impact shattered rock for miles, letting seawater infiltrate. Few Indian groups lived in the saltwater wedge, presumably for just that reason. Jamestown was bordered and undergirded by bad water. That bad water, the geographer Carville V. Earle argued, led to 'typhoid, dysentery, and perhaps salt poisoning.' By January 1608, eight months after landfall, only thirty-eight [of the original 144] English were left alive."
From Charles Mann's "1493", which is a fantastic read; it's full of satisfying connections between environmental and historical forces like the above.
"Chesapeake Bay is the remains of a giant meteor crater. The impact shattered rock for miles, letting seawater infiltrate. Few Indian groups lived in the saltwater wedge, presumably for just that reason. Jamestown was bordered and undergirded by bad water. That bad water, the geographer Carville V. Earle argued, led to 'typhoid, dysentery, and perhaps salt poisoning.' By January 1608, eight months after landfall, only thirty-eight [of the original 144] English were left alive."
From Charles Mann's "1493", which is a fantastic read; it's full of satisfying connections between environmental and historical forces like the above.
Haven't read 1493 yet, but looking forward to it. Read 1491 about a decade ago and it blew my mind. You just pushed 1493 back up towards the top of my "to read" list :)
I think it was 1491 where I first encountered the idea that red earthworms are invasive and the real reason "great forests" are in decline.
I think it was 1491 where I first encountered the idea that red earthworms are invasive and the real reason "great forests" are in decline.
Looking at this map[1] of known impact craters, it looks like of the landmasses, eastern Canada, (western) Australia and northern Eurasia have experienced the most impacts and Africa, China and South America have experienced the fewest (Antarctica largely unknown).
Now one thing which the map doesn’t represent is the position (coöperdinates) of the affected landmass at time of impact.
[1]https://upload.wikimedia.org/wikipedia/commons/c/cc/Earth_Im...
Now one thing which the map doesn’t represent is the position (coöperdinates) of the affected landmass at time of impact.
[1]https://upload.wikimedia.org/wikipedia/commons/c/cc/Earth_Im...
The results are affected by the density of geologists.
What’s interesting is the lack of “discoveries” in the Middle East, given the amount of drilling and geological work going on there. I guess when the oil is easy, there’s no motivation to look too hard.
It may also be that the area is geologically newer. (Disclaimer: I have no idea if it is.)
Yep, just like dinosaur fossils.
Africa, China and South America have wonderful geologists and people just like America and Europe. What are you trying to say?
There have been more geologists per area in the places where lots of astroblemes have been found. It's a selection effect, not a real effect.
> Africa, China and South America have wonderful geologists and people just like America and Europe.
Sure, but geology was largely created by Christians looking for proof that the bible was true, and then was later developed by people looking to prove that Christianity was false. So you have more geologists in areas with lots of people who have an axe to grind one way or the other with respect to that religion.
Sure, but geology was largely created by Christians looking for proof that the bible was true, and then was later developed by people looking to prove that Christianity was false. So you have more geologists in areas with lots of people who have an axe to grind one way or the other with respect to that religion.
I like that the Carancas impact event is listed as .000007 mya. I happened in 2007.
Could be related to age of crust?
All the continents have very old parts.
https://en.wikipedia.org/wiki/List_of_shields_and_cratons
https://en.wikipedia.org/wiki/List_of_shields_and_cratons
Caught in a wave of post-war growth, white flight, threatened by annexation, and discontent with having to buy local water from their neighbors, counties in this part of Virginia started becoming cities. In Virginia, cities are independent from counties -- the federal government therefore considers Virginia cities to be county-equivalent -- and cities are protected from annexation by adjacent cities.
Counties turned into cities, then merged with an adjacent friendly city to avoid annexation by a rival city; Princess Anne County merged into the City of Virginia Beach; Norfolk County merged with the City of South Norfolk and renamed itself to Chesapeake; Nansemond County changed into a city, then a year and half later merged into the City of Suffolk; the county surrounding the City of Hampton merged back into it; and the City of Newport News eventually merged by mutual agreement with the City of Warwick, even though 6 years prior Warwick changed from a county to a city to avoid that exact fate.
After experiencing major growth, Virginia Beach wanted to have a better negotiating position with Norfolk over water supply. It build a long interbasin transfer [1][2] to withdraw water from Lake Gaston on the Roanoke River, adjacent to the North Carolina border. Chesapeake joined as a minority partner. The resulting water is delivered into to Norfolk's system, who filters and treats it, and distributes it to Norfolk, Virginia Beach, the most urbanized areas of Chesapeake, and most military bases in the area.
[1] http://www.virginiaplaces.org/watersheds/lakegaston.html [2] https://www.vbgov.com/government/departments/public-utilitie...