Glass from the Cretaceous/Tertiary boundary in Haiti

  title={Glass from the Cretaceous/Tertiary boundary in Haiti},
  author={Haraldur Sigurdsson and Steven D’Hondt and Michael A. Arthur and Timothy J. Bralower and James C. Zachos and Mickey C. Van Fossen and James E. T. Channel},
Tektite-like glasses preserved at the Cretaceous/Tertiary boundary at Beloc in Haiti provide clear evidence of an impact event. The glass composition suggests that the impact occurred on a continental shelf region, generating a silica-rich glass with chemical composition that reflects the melting of continental crustal rocks, and a calcium-rich glass produced by the fusion of marl sediments. These findings indicate that catastrophic release to the atmosphere of 1015 moles of C02 from vaporized… 

Geochemical constraints on source region of Cretaceous/Tertiary impact glasses

THE 50-cm-thick Cretaceous/Tertiary boundary layer at Beloc in Haiti contains spherules of silicic black glass, 1–8 mm in diameter, which have been attributed to impact fusion of continental crust1.

Oxygen Isotope Constraints on the Origin of Impact Glasses from the Cretaceous-Tertiary Boundary

Detailed laser-extraction oxygen isotope and major element analyses of individual glass spherules from Haitian Cretaceous-Tertiary boundary sediments indicate that the glasses are a mixture of carbonate and silicate rocks and exclude derivation of the glasses either by volcanic processes or as mixtures of sulfate-rich evaporated rocks.

Complex tsunami waves suggested by the Cretaceous-Tertiary boundary deposit at the Moncada section, western Cuba

The Moncada Formation in western Cuba is an 2-m-thick weakly metamorphosed complex characterized by repetition of calcareous sandstone units that show overall upward fining and thinning. The Moncada

40Ar/39Ar Age of Cretaceous-Tertiary Boundary Tektites from Haiti

40Ar/39Ar dating of tektites discovered recently in Cretaceous-Tertiary (K-T) boundary marine sedimentary rocks on Haiti indicates that the K-T boundary and impact event are coeval at 64.5 � 0.1

Sferule z granicy Kreda-Paleogen (Lechówka, Polska) – wstępne dane

: Samples of boundary clay from Cretaceous–Paleogene deposits from Lechówka, Poland were examined for spherules to confirm the impact origin of the sediment. The chemical composition of investigated

Emplacement of Cretaceous-Tertiary Boundary Shocked Quartz from Chicxulub Crater

Shock devolatilization and the expansion of carbon dioxide and water from impacted wet carbonate, producing a warm, accelerating fireball after the initial hot fireball of silicate vapor, may explain all three problems.



Mineralogic Evidence for an Impact Event at the Cretaceous-Tertiary Boundary

A thin claystone layer found in nonmarine rocks at the palynological Cretaceous-Tertiary boundary in eastern Montana contains an anomalously high value of iridium, suggesting a high velocity impact between a large extraterrestrial body and the earth.

Trace element patterns at a non-marine Cretaceous–Tertiary boundary

At the fossil-pollen-defined Cretaceous–Tertiary boundary in the Raton Basin of New Mexico and Colorado, an iridium abundance anomaly and excess scandium, titanium, and chromium are associated with a

Late Cretaceous and paroxysmal Cretaceous/Tertiary extinctions

The various geological signatures at Cretaceous/ Tertiary time including iridium and other associated elements, microspherules, and shock deformation features are compatible with the suggestion that

Sanidine spherules at the Cretaceous–Tertiary boundary indicate a large impact event

The hypothesis that a catastrophic impact of an extraterrestrial body caused the terminal Cretaceous mass extinctions of dinosaurs, planktonic foraminfera and other species is now accepted as

Proximal Cretaceous-Tertiary Boundary Impact Deposits in the Caribbean

Trace element, isotopic, and mineralogic studies indicate that the proposed impact at the Cretaceous-Tertiary (K-T) boundary occurred in an ocean basin, although a minor component of continental

Authigenic “spherules” in K-T boundary sediments at Caravaca, Spain, and Raton Basin, Colorado and New Mexico, may not be impact derived

The K-T boundary interval at Barranco del Gredero, Caravaca, Spain, consists of three units: a light gray Cretaceous marl, a 1- to 3-mm-thick ferruginous clay called the “K-T boundary impact layer”

Probing the evolving Andean Lithosphere: Mid‐Late Tertiary magmatism in Chile (29°–30°30′S) over the modern zone of subhorizontal subduction

In the mid-late Tertiary (27–6 m.y. ago), volcanism diminished, then ceased in the main Andean Cordillera in Chile between 29° and 30°30′S. Over the same time span the subduction angle shallowed