Purgatory Conglomerate

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Purgatory Conglomerate
Stratigraphic range: Carboniferous (Pennsylvanian)
Type Formation
Unit of Narragansett Bay Group
Informal: Rhode Island Group (RI) [1]
Lithology
Primary"near metamorphic" conglomerate
Location
Region New England (Rhode Island) [1]
Country United States
Type section
Named forPurgatory, Middletown, Newport, RI

Dating to the Carboniferous period, the Purgatory Conglomerate is a geologic formation in Rhode Island. [1] [2] [3] [4] [5] [6]

Purgatory Chasm

Purgatory Chasm in Middletown Purgatory Chasm in Middletown, Rhode Island.jpg
Purgatory Chasm in Middletown

Purgatory Chasm, at the intersection of Tuckerman Avenue and Purgatory Road in Middletown (often mis-identified as being in Newport), is a narrow cleft on the east side of Easton Point which splits the Purgatory Conglomerate in a dramatic fashion. [7] [8] The chasm is 120 feet long, 10 feet wide at the top, and over 150 feet deep. [9]

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References

  1. 1 2 3 "Geologic Unit: Purgatory". National Geologic Database. Geolex — Significant Publications. United States Geological Survey . Retrieved 2021-03-26.
  2. August 29, 2016 Chris Watson (August 29, 2016). "KVH Tackles Difficult Problems – Even Coastal Pollution Near its RI Headquarters". Company. KVH Mobile World. Retrieved 2021-03-27. Scientists are intrigued by the formation. Geologists cite the significance of Purgatory Chasm – Purgatory Conglomerate is their name for it – as an important example of erosion due to wave action and as an illustration of rock compression millions of years ago.{{cite web}}: CS1 maint: numeric names: authors list (link)
  3. S Mosher (1987). "Pressure-solution deformation of the purgatory conglomerate, rhode island (u.s.a.): quantification of volume change, real strains and sedimentary shape factor". Journal of Structural Geology. 9 (2): 221–232. doi:10.1016/0191-8141(87)90027-7 . Retrieved 2021-03-27. Pressure solution has caused substantial volume redistribution within the Purgatory Conglomerate from Rhode Island.
  4. Yvette D. Kuiper, Boston College. "Deformation Mechanisms and History of the Purgatory Conglomerate, Rhode Island". Annual Report on Research. 54th (47487–GB8). ACS Petroleum Research Fund. Retrieved 2021-03-27. The Purgatory Conglomerate of Rhode Island experienced two generations of Alleghanian folding, and subsequent local shearing.
  5. "Pebbles of Purgatory Chasm". Events. Audubon Society of Rhode Island. Retrieved 2021-03-27. Purgatory Chasm in Newport cuts into one of Rhode Island's most spectacular rock formations: the Purgatory conglomerate.
  6. McPherren, Eric D.; Kuiper, Yvette D. (June 2013). "The effects of Dissolution-Precipitation Creep on quartz fabrics within the Purgatory Conglomerate, Rhode Island". Journal of Structural Geology . 51: 105-117. Bibcode:2013JSG....51..105M. doi:10.1016/j.jsg.2013.03.002 . Retrieved 2021-03-27.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  7. Berman, Eleanor (2010). DK Eyewitness Travel Guide: New England. Penguin. p. 181. ISBN   0756666724 . Retrieved 22 April 2024.
  8. "Pebbles of Purgatory Chasm - Newport". Audubon Society of Rhode Island. Rhode Island: Audubon Society of Rhode Island. Archived from the original on 9 June 2013. Retrieved 22 April 2024. Purgatory Chasm in Newport cuts into one of Rhode Island's most spectacular rock formations: the Purgatory conglomerate
  9. Clunan, Natalie (23 July 2018). "The Shortest Hike In Rhode Island Leads To The Most Amazing Natural Wonder". Only in Your State. Archived from the original on 26 September 2023. Retrieved 22 April 2024.