SI
SI
discoversearch

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor.  We ask that you disable ad blocking while on Silicon Investor in the best interests of our community.  If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.
Gold/Mining/Energy : Flag Resources (FGR.A A)
 Public ReplyPrvt ReplyMark as Last ReadFilePrevious 10Next 10PreviousNext  
To: sinclair99 who wrote (2783)3/11/2000 12:59:00 AM
From: Natedog  Read Replies (1) of 4269
 
very cool, thank you.

The partially circular lake-filled structure on the right (east) is the 8 km (5 mile) wide Wanapitei crater estimated to have been formed 34 m.y. ago. The far larger Sudbury structure is evidenced by a pronounced elliptical pattern, more strongly expressed by the low hills to the north. This huge impact crater (some argue it was at least 245 km [150 miles] across when it was circular) was created about 1800 million years ago. It was subsequently deformed by the strong northwestward thrusting of the Grenville Province terrane against the Superior Province (containing Sudbury) more than 900 million years later. After Sudbury was initially excavated, magmas from deep in the crust invaded the breccia filling to emplace against its walls (some investigators think that the resulting norite rocks are actually melted target rocks). This igneous rock is host to vast deposits of nickel and copper, making this impact structure a multi-billion dollar source of ore minerals.

Radar can sharpen the appearance of an impact structure, as demonstrated with this aerial radar image of the Haughton crater (24 km; 15miles wide) in Canada. Although about 23 million years old, much of the crater's morphology has survived erosion.
Report TOU ViolationShare This Post
 Public ReplyPrvt ReplyMark as Last ReadFilePrevious 10Next 10PreviousNext  

HomeMailHotSubjectMarksPeopleMarksKeepersSettings
Terms Of UseContact UsCopyright/IP PolicyPrivacy PolicyAbout UsFAQAdvertise on SI
© 2025 Knight Sac Media.  Data provided by Twelve Data, Alpha Vantage, and CityFALCON News