File:Shatterconed sandstone (Mississagi Formation, Paleoproterozoic, ~2.3-2.4 Ga; Ramsey Lake Road outcrop, Sudbury, Ontario, Canada) 1 (40800830493).jpg

From Wikimedia Commons, the free media repository
Jump to navigation Jump to search

Original file (4,000 × 3,000 pixels, file size: 9.2 MB, MIME type: image/jpeg)

Captions

Captions

Add a one-line explanation of what this file represents

Summary

[edit]
Description

Shatterconed sandstone in Ontario, Canada.

Shattercones are striated conical structures in rocks formed by a powerful shock wave or pressure front moving through during an impact event. They have a three-dimensional cone-like structure, with the points of the cones directed toward the shock wave origination site. Undisturbed shatterconed rocks will have the apex of the cones pointing toward the direction of the incoming object (i.e., upward - toward space).

The host rocks here consist of ~2.3 to 2.4 billion year old fluvial sandstones of the Mississagi Formation. Notice that the shattercones are pointing downward, indicating that the impact event also overturned the beds.

This outcrop is in the Sudbury Impact Structure, the site for one of the largest impact events in Earth history. The impact structure, located in southeastern Ontario, is ovoid in shape, about 37 miles long by 19 miles wide. It was originally ~circular, but has since been laterally compressed by tectonic deformation. Before erosion and structural deformation, the structure may have been between 60 and 120 miles across. The impacting object is estimated to have been about 6 miles in size. The impact event itself occurred at 1.85 billion years ago. At that time, this part of Ontario was ocean. Computer modeling indicates that the splash wave generated by the Sudbury Impact may have reached about 30 miles high and generated a ~300 feet high megatsunami that radiated away from the target area for up to ~1800 miles. The impact punched a hole down into underlying mantle rocks.

Abundant evidence indicates that the Sudbury, Ontario area was indeed the site of an impact long ago. This includes impact breccias, shattercones, and extensive syn-formational sulfide mineralization. The sulfides are rich enough for mining to occur. In fact, the Sudbury Mining District targets the # 1 most productive nickel deposit on Earth.


This is a no-hammer outcrop.


Stratigraphy: Mississagi Formation, upper Hough Lake Group, Huronian Supergroup, Paleoproterozoic, ~2.3 to 2.4 Ga

Locality: Ramsey Lake Road outcrop - roadcut on the southern side of Ramsey Lake Road, ~0.9 miles east of Paris Street (a.k.a. Long Lake Road; a.k.a. Route 80), southern side of the city of Sudbury, Sudbury Impact Structure, Ontario, southeastern Canada (46° 28’ 06.97" North latitude, 80° 58’ 46.21" West longitude)
Date
Source Shatterconed sandstone (Mississagi Formation, Paleoproterozoic, ~2.3-2.4 Ga; Ramsey Lake Road outcrop, Sudbury, Ontario, Canada) 1
Author James St. John

Licensing

[edit]
w:en:Creative Commons
attribution
This file is licensed under the Creative Commons Attribution 2.0 Generic license.
You are free:
  • to share – to copy, distribute and transmit the work
  • to remix – to adapt the work
Under the following conditions:
  • attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
This image was originally posted to Flickr by James St. John at https://flickr.com/photos/47445767@N05/40800830493 (archive). It was reviewed on 10 October 2019 by FlickreviewR 2 and was confirmed to be licensed under the terms of the cc-by-2.0.

10 October 2019

File history

Click on a date/time to view the file as it appeared at that time.

Date/TimeThumbnailDimensionsUserComment
current01:20, 10 October 2019Thumbnail for version as of 01:20, 10 October 20194,000 × 3,000 (9.2 MB)Ser Amantio di Nicolao (talk | contribs)Transferred from Flickr via #flickr2commons

There are no pages that use this file.

Metadata