Eocene clinopyroxene-bearing spherule layer - Impact Deposit

Alternate Names Cpx spherule layer, Eocene microkrystite layer
Coordinates 0° 0' 0" ; 0° 0' 0" 
Notes
  1. There is an excellent figure of this strewn field in Glass, 2002; Glass et al., 1985; Liu et al., 2009
Country Mexico

Related Countries :
  1. Mexico
Region Caribbean Sea; Gulf of Mexico; equatorial Pacific; eastern equatorial Indian Ocean; western Indian Ocean; Massignano, Italy; North America
Date Confirmed 1973
Notes
  1. Donnelly and Chao, 1973
Age (Ma) ~35
Notes :
  1. The cpx layer occurs in magneton 16n.1n and lies between the last occurances of Dicoaster saipanensis and Chiasmolithus grandis. The published ages of these last occurances are 34.2 and 37.1 Ma, respectively, which is in line with age of the cpx layer (Liu et al., 2009)

Method :
  1. Biostratigraphy and magnetostratigraphy
Impactor Type Unknown

Advanced Data Fields

Notes

Local Language
N/A
Spherules
Yes
Tektites
Unknown
Indivudual Glass Clasts
Unknown
Source Crater
Popigai crater in Siberia (Whitehead et al., 2000)
Geology
Late Eocene; This layer is often associated with the North American strewn field and were once considered part of the same impact event. Further analysis has shown that they have distinct chemistry and ages
  1. Glass et al., 2004; Liu et al., 2009
Other Shock Metamorphism
Unknown
Shatter Cones
No
Planar Fractures
No
Planar Deformation Features
Yes
  1. Liu et al., 2009
Diaplectic Glass
No
Coesite
Yes
  1. Liu et al., 2009
Stisovite
No

References

Spot a missing reference? Submit Reference

T W Donnelly, E C T Chao (1973) Microtektites of late Eocene age from the eastern Caribbean Sea, Inital Reports Deep Sea Drilling Project 15, p. 1031-1037, url

B P Glass, C A Burns, J R Crosbie, D L DuBois (1985) Late Eocene North American microtektites and clinopyroxene-bearing spherules, Journal of Geophysical Research 90(S01), p. 196, American Geophysical Union (AGU), url, doi:10.1029/jb090is01p00175

J Whitehead, D A Papanastassiou, J G Spray, R A F Grieve, G J Wasserburg (2000) Late Eocene impact ejecta: Geochemical and isotopic connections with the Popigai impact structure, Earth and Planetary Science Letters 181, p. 473-487, url, doi:10.1016/S0012-821X(00)00225-9

B P Glass (2002) Upper Eocene impact ejecta/spherule layers in marine sediments, Geochemistry 62(3), p. 173-196, doi:10.1078/0009-2819-00017

B P Glass, L E Edwards, J W Horton Jr, G S Gohn (2004) Distal impact ejecta from the Chesapeake Bay impact crater, Open-File Report - U. S. Geological Survey, p. 22-23, U. S. Geological Survey, Reston, VA, url

S Liu, B P Glass, F T Kyte, S M Bohaty (2009) The late Eocene clinopyroxene-bearing spherule layer: New sites, nature of the strewn field, Ir data, and discovery of coesite and shocked quartz, The Late Eocene Earth: Hothouse, Icehouse, and Impacts 452, C Koeberl, A Montanari (ed.), p. 37-70, Boulder, Colarado: The Geological Society of America Special Paper, url