Montanari, Alessandro et al. (1983): Spheroids at the Cretaceous-Tertiary boundary are altered impact droplets of basaltic composition

Leg/Site/Hole:
DSDP 62
DSDP 62 465
Identifier:
1983-061203
georefid
Creator:
Montanari, Alessandro
Univ. Calif., Dep. Geol. and Geophys., Berkeley, CA, United States
author
Hay, Richard L.
Univ. Amsterdam, Netherlands
author
Alvarez, Walter
author
Asaro, Frank
author
Michel, Helen V.
author
Alvarez, Luis W.
author
Smit, Jan
author
Identification:
Spheroids at the Cretaceous-Tertiary boundary are altered impact droplets of basaltic composition
1983
Geology (Boulder)
Geological Society of America (GSA), Boulder, CO, United States
11
11
668-671
Spheroids of K-feldspar in boundary clay at Caravaca, southern Spain. Sand-size spheroids of K-feldspar, glauconite, and magnetite-quartz have been found in the C-T boundary clay in northern Italy, and spheroids of K-feldspar and pyrite were found in the boundary clay at Deep Sea Drilling Project Site 465A, in the central Pacific. Textures are similar to those of rapidly crystallized feldspar and mafic silicates. Diagenetically altered microcrystalline spherules of basaltic composition produced by the impact of a large asteroid in an ocean basin at the end of the Cretaceous. Analogous to the glassy microtektites produced by impacts on more siliceous target rocks.--Modified journal abstract.
English
Serial
Coverage:Geographic coordinates:
North:45.3642
West:-2.2000East: 12.3842
South:32.0000
Stratigraphy; alkali feldspar; basaltic composition; Caravaca Spain; Cenozoic; clastic sediments; clay; Cretaceous; Deep Sea Drilling Project; diagenesis; DSDP Site 465; Europe; feldspar group; framework silicates; glauconite; Hess Rise; Iberian Peninsula; impact features; impacts; IPOD; Italy; K-feldspar; Leg 62; lithostratigraphy; lower Tertiary; magnetite; Mesozoic; mica group; mineral composition; Murcia Province; Murcia region; Murcia Spain; North Pacific; Northwest Pacific; oceanography; oxides; Pacific Ocean; Paleocene; Paleogene; Petriccio; pyrite; quartz; sedimentary petrology; sediments; sheet silicates; silica minerals; silicates; Southern Europe; Spain; spherules; stratigraphic boundary; stratigraphy; sulfides; Tertiary; textures; Upper Cretaceous; Veneto Italy; West Pacific;
.