Oceanography The Official Magazine of
The Oceanography Society
Volume 32 Issue 01

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Volume 32, No. 1
Pages 120 - 134

Ocean Drilling Perspectives on Meteorite Impacts

Christopher M. Lowery Joanna V. MorganSean P.S. GulickTimothy J. BralowerGail L. Christesonthe Expedition 364 Scientists
Article Abstract

Extraterrestrial impacts that reshape the surfaces of rocky bodies are ubiquitous in the solar system. On early Earth, impact structures may have nurtured the evolution of life. More recently, a large meteorite impact off the Yucatán Peninsula in Mexico at the end of the Cretaceous caused the disappearance of 75% of species known from the fossil record, including non-avian dinosaurs, and cleared the way for the dominance of mammals and the eventual evolution of humans. Understanding the fundamental processes associated with impact events is critical to understanding the history of life on Earth, and the potential for life in our solar system and beyond.

Scientific ocean drilling has generated a large amount of unique data on impact processes. In particular, the Yucatán Chicxulub impact is the single largest and most significant impact event that can be studied by sampling in modern ocean basins, and marine sediment cores have been instrumental in quantifying its environmental, climatological, and biological effects. Drilling in the Chicxulub crater has significantly advanced our understanding of fundamental impact processes, notably the formation of peak rings in large impact craters, but these data have also raised new questions to be addressed with future drilling. Within the Chicxulub crater, the nature and thickness of the melt sheet in the central basin is unknown, and an expanded Paleocene hemipelagic section would provide insights to both the recovery of life and the climatic changes that followed the impact. Globally, new cores collected from today’s central Pacific could directly sample the downrange ejecta of this northeast-southwest trending impact.

Extraterrestrial impacts have been controversially suggested as primary drivers for many important paleoclimatic and environmental events throughout Earth history. However, marine sediment archives collected via scientific ocean drilling and geochemical proxies (e.g., osmium isotopes) provide a long-term archive of major impact events in recent Earth history and show that, other than the end-Cretaceous, impacts do not appear to drive significant environmental changes.


Lowery, C.M., J.V. Morgan, S.P.S. Gulick, T.J. Bralower, G.L. Christeson, and the Expedition 364 Scientists. 2019. Ocean drilling perspectives on meteorite impacts. Oceanography 32(1):120–134, https://doi.org/10.5670/oceanog.2019.133.


Adams, J.B., M.E. Mann, and S. D’Hondt. 2004. The Cretaceous-Tertiary extinction: Modeling carbon flux and ecological response. Paleoceanography 19, PA1002, https://doi.org/​10.1029/2002PA000849.

Alegret, L., E. Thomas, and K.C. Lohmann. 2012. End-Cretaceous marine mass extinction not caused by productivity collapse. Proceedings of the National Academy of Sciences of the United States of America 109:728–732, https://doi.org/10.1073/pnas.1110601109.

Alroy, J. 2008. Dynamics of origination and extinction in the marine fossil record. Proceedings of the National Academy of Sciences of the United States of America 105:11,536–11,542, https://doi.org/​10.1073/pnas.0802597105.

Alvarez, L.W., W. Alvarez, F. Asaro, and H.V. Michel. 1980. Extraterrestrial cause of the Cretaceous–Tertiary extinction. Science 208:1,095–1,108, https://doi.org/10.1126/science.208.4448.1095.

Alvarez, W., L.W. Alvarez, F. Asaro, and H.V. Michel. 1982. Current status of the impact theory for the terminal Cretaceous extinction. Pp. 305–315 in Geological Implications of Impacts of Large Asteroids and Comets on the Earth. GSA Special Paper 190, L.T. Silver and P.H. Schultz, eds, Geological Society of America, Boulder, Colorado, https://doi.org/10.1130/SPE190-p305.

Alvarez, W., P. Claeys, and S. Kieffer. 1995. Emplacement of Cretaceous-Tertiary boundary shocked quartz from Chicxulub crater. Science 269:930–935, https://doi.org/10.1126/science.269.5226.930.

Argyle, E. 1989. The global fallout signature of the K-T bolide impact. Icarus 77:220–222, https://doi.org/​10.1016/0019-1035(89)90018-3.

Artemieva, N., and J. Morgan. 2009. Modeling the formation of the K-Pg boundary layer. Icarus 201:768–780, https://doi.org/10.1016/​j.icarus.2009.01.021.

Artemieva, N., J. Morgan, and the Expedition 364 Science Party. 2017. Quantifying the release of climate-​active gases by large meteorite impacts with a case study of Chicxulub. Geophysical Research Letters 44(20):10,180–10,188, https://doi.org/​10.1002/​2017GL074879.

Baker, D.M.H., J.W. Head, G.S. Collins, and R.W.K. Potter. 2016. The formation of peak-ring basins: Working hypotheses and path forward in using observations to constrain models of impact-basin formation. Icarus 273:146–163, https://doi.org/​10.1016/j.icarus.2015.11.033.

Bermúdez, H.D., J. García, W. Stinnesbeck, G. Keller, J.V. Rodrígez, M. Hanel, J. Hopp, W.H. Schwarz, M. Trieloff, L. Bolivar, and F.J. Vega. 2016. The Cretaceous-Palaeogene boundary at Gorgonilla Island, Colombia, South America. Terra Nova 28:83–90, https://doi.org/10.1111/ter.12196.

Bernaola, G., and S. Monechi. 2007. Calcareous nannofossil extinction and survivorship across the Cretaceous-Paleogene boundary at Walvis Ridge (ODP Hole 1262C, South Atlantic Ocean). Palaeogeography, Palaeoclimatology, Palaeoecology 255:132–156, https://doi.org/​10.1016/j.palaeo.2007.02.045.

Birch, H.S., H.K. Coxall, P.N. Pearson, D. Kroon, and D.N. Schmidt. 2016. Partial collapse of the marine carbon pump after the Cretaceous-Paleogene boundary. Geology 44:287–290, https://doi.org/​10.1130/G37581.1.

Bohor, B.F., E.E. Foord, P.J. Modreski, and D.M. Triplehorn. 1984. Mineralogic evidence for an impact event at the Cretaceous-Tertiary boundary. Science 224:867–869, https://doi.org/10.1126/science.224.4651.867.

Bohor, B.F., E.E. Foord, and W.J. Betterton. 1989. Trace minerals in K-T boundary clays. Meteoritics 24:253.

Bohor, B.F., and W.J. Betterton. 1993. Arroyo el Mimbral, Mexico, K/T unit: Origin as debris flow/turbidite, not a tsunami deposit. Proceedings of the Lunar and Planetary Science Conference 24:143–144.

Bohor, B.F., W.J. Betterton, and T.E. Krogh. 1993. Impact-shocked zircons: Discovery of shock-​induced textures reflecting increasing degrees of shock metamorphism. Earth and Planetary Science Letters 119:419–424, https://doi.org/​10.1016/0012-821X(93)90149-4.

Bohor, B.F., and B.P. Glass. 1995. Origin and diagenesis of K/T impact spherules: From Haiti to Wyoming and beyond. Meteoritics & Planetary Science 30:182–198, https://doi.org/​10.1111/​j.1945-5100.1995.tb01113.x.

Bottomley, R., R. Grieve, D. York, and V. Masaitis. 1997. The age of the Popigai impact event and its relation to events at the Eocene/Oligocene boundary. Nature 388:365–368, https://doi.org/10.1038/41073.

Bourgeois, J., T.A. Hansen P.L. Wiberg, and E.G. Kauffman. 1988. A tsunami deposit at the Cretaceous-Tertiary boundary in Texas. Science 241:567–570, https://doi.org/10.1126/science.241.4865.567.

Bown, P. 2005. Selective calcareous nannoplankton survivorship at the Cretaceous-Tertiary boundary. Geology 33:653–656.

Bown, P.R., J.A. Lees, and J.R. Young. 2004. Calcareous nannoplankton evolution and diversity through time. Pp. 481–508 in Coccolithophores. H.R. Thierstein and J.R. Young, eds, Springer.

Bralower, T., C.K. Paull, and R.M. Leckie. 1998. The Cretaceous-Tertiary boundary cocktail: Chicxulub impact triggers margin collapse and extensive gravity flows. Geology 26:331–334, https://doi.org/10.1130/0091-7613(1998)026​<0331:TCTBCC>2.3.CO;2.

Bralower, T.J., I.P. Silva, and M.J. Malone. 2002. New evidence for abrupt climate change in the Cretaceous and Paleogene: An Ocean Drilling Program expedition to Shatsky Rise, northwest Pacific. GSA Today 12:4–10.

Buffler, R.T., W. Schlager, and K.A. Pisciotto. 2007. Introduction and explanatory notes. In Initial Reports of the Deep Sea Drilling Project vol. 77. R.T. Buffler, W. Schlanger, et al., US Government Printing Office, Washington, DC, https://doi.org/​10.2973/dsdp.proc.77.1984.

Brugger, J., G. Feulner, and S. Petri. 2017. Baby, it’s cold outside: Climate model simulations of the effects of the asteroid impact at the end of the Cretaceous. Geophysical Research Letters 44:419–427, https://doi.org/​10.1002/2016GL072241.

Chenet, A.L., V. Courtillot, F. Fluteau, M. Gérard, X. Quidelleur, S.F.R. Khadri, K.V. Subbarao, and T. Thordarson. 2009. Determination of rapid Deccan eruptions across the Cretaceous-Tertiary boundary using paleomagnetic secular variation: Part 2. Constraints from analysis of eight new sections and synthesis for a 3500-m-thick composite section. Journal of Geophysical Research: Solid Earth 114, B06103, https://doi.org/​10.1029/2008JB005644.

Christeson, G.L., S.P.S. Gulick, J.V. Morgan, C. Gebhardt, D.A. King, E. Le Bar, J. Lofi, C. Nixon, M. Poelchau, A.S.P. Rae, and others. 2018. Extraordinary rocks from the peak ring of the Chicxulub impact crater: P-wave velocity, density, and porosity measurements from IODP/ICDP Expedition 364. Earth and Planetary Science Letters 495:1–11, https://doi.org/10.1016/​j.epsl.2018.05.013.

Cintala, M.J., and R.A. Grieve. 1998. Scaling impact melting and crater dimensions: Implications for the lunar cratering record. Meteoritics & Planetary Science 33:889–912, https://doi.org/​10.1111/​j.1945-5100.1998.tb01695.x.

Claeys, P., W. Kiessling, and W. Alvarez. 2002. Distribution of Chicxulub ejecta at the Cretaceous Tertiary boundary. Pp. 55–68 in Catastrophic Events and Mass Extinctions: Impacts and Beyond. C. Koeberl and K.G. MacLeod, eds, Geological Society of America Special Paper 356.

Collins, G.S., N. Patel, A.S. Rae, T.M. Davies, J.V. Morgan, S.P.S. Gulick, and Expedition 364 Scientists. 2017. Numerical simulations of Chicxulub crater formation by oblique impact. Lunar and Planetary Science Conference XLVII, abstract #1832.

Coxall, H.K., S. D’Hondt, and J.C. Zachos. 2006. Pelagic evolution and environmental recovery after the Cretaceous-Paleogene mass extinction. Geology 34:297–300, https://doi.org/10.1130/G21702.1.

Croskell, M., M. Warner, and J. Morgan. 2002. Annealing of shocked quartz during atmospheric reentry. Geophysical Research Letters 29:1,940–1,944, https://doi.org/​10.1029/​2001GL014382.

Culver, S.J. 2003. Benthic foraminifera across the Cretaceous-Tertiary (K-T) boundary: A review. Marine Micropaleontology 47:177–226, https://doi.org/​10.1016/S0377-8398(02)00117-2.

D’Hondt, S., and G. Keller. 1991. Some patterns of planktic foraminiferal assemblage turnover at the Cretaceous-Tertiary boundary. Marine Micropaleontology 17:77–118, https://doi.org/​10.1016/​0377-8398(91)90024-Z.

D’Hondt, S., P. Donaghay, J.C. Zachos, D. Luttenberg, and M. Lindinger. 1998. Organic carbon fluxes and ecological recovery from the Cretaceous-Tertiary mass extinction. Science 282:276–279.

D’Hondt, S. 2005. Consequences of the Cretaceous/Paleogene mass extinction for marine ecosystems. Annual Reviews of Ecology, Evolution, and Systematics 36:295–317, https://doi.org/10.1146/annurev.ecolsys.35.021103.105715.

Denne, R.A., E.D. Scott, D.P. Eickhoff, J.S. Kaiser, R.J. Hill, and J.M. Spaw. 2013. Massive Cretaceous-Paleogene boundary deposit, deep-water Gulf of Mexico: New evidence for widespread Chicxulub-induced slope failure. Geology 41:983–986, https://doi.org/​10.1130/G34503.1.

Ebel, D.S., and L. Grossman. 2005. Spinel-bearing spherules condensed from the Chicxulub impact-vapor plume. Geology 33:293–296, https://doi.org/10.1130/G21136.1.

Ekholm, A.G., and H.J. Melosh. 2001. Crater features diagnostic of oblique impacts: The size and position of the central peak. Geophysical Research Letters 28:623–626, https://doi.org/​10.1029/2000GL011989.

Fraass, A.J., D.C. Kelly, and S.E. Peters. 2015. Macroevolutionary history of the planktic foraminifera. Annual Review of Earth and Planetary Sciences 43:139–166, https://doi.org/10.1146/annurev-earth-060614-105059.

Glass, B.P., C.A. Burns, J.R. Crosbie, and D.L. DuBois. 1985. Late Eocene North American microtektites and clinopyroxene-bearing spherules. Journal of Geophysical Research: Solid Earth 90:175–196, https://doi.org/10.1029/JB090iS01p00175.

Glass, B.P., and C.A. Burns. 1988. Microkrystites: A new term for impact-produced glassy spherules containing primary crystallites. Pp. 455–458 in Proceedings of 18th Lunar and Planetary Science Conference, March 16–20, 1987, Houston, Texas.

Glass, B.P. 2002. Upper Eocene impact ejecta/spherule layers in marine sediments. Chemie der Erde-Geochemistry 62(3):173–196, https://doi.org/​10.1078/0009-2819-00017.

Gohn, G.S., C. Koeberl, K.G. Miller, W.U. Reimold, J.V. Browning, C.S. Cockell, J.W. Horton Jr., T. Kenkmann, A. Kulpecz, D.S. Powars, and others. 2008. Deep drilling into the Chesapeake Bay impact structure. Science 320:1,740–1,745, https://doi.org/​10.1126/science.1158708.

Goldin, T.J., and H.J. Melosh. 2007. Interactions between Chicxulub ejecta and the atmosphere: The deposition of the K/T double layer. Paper presented at the 38th Lunar and Planetary Science Conference, 2114, #1338.

Goldin, T.J., and H.J. Melosh. 2008. Chicxulub ejecta distribution, patchy or continuous? Paper presented at the 39th Lunar and Planetary Science Conference, #2469.

Gulick, S.P.S., P.J. Barton, G.L. Christeson, J.V. Morgan, M. McDonald, K. Mendoza-Cervantes, Z.F. Pearson, A. Surendra, J. Urrutia-Fucugauchi, P.M. Vermeesch, and M.R. Warner. 2008. Importance of pre-impact crustal structure for the asymmetry of the Chicxulub impact crater. Nature Geoscience 1:131, https://doi.org/10.1038/ngeo103.

Gulick, S.P.S., G.L. Christeson, P.J. Barton, R.A.F. Grieve, J.V. Morgan, and J. Urrutia-Fucugauchi. 2013. Geophysical characterization of the Chicxulub impact crater. Reviews of Geophysics 51:31–52, https://doi.org/10.1002/rog.20007.

Grajales-Nishimura, J.M., E. Cedillo-Pardo, C. Rosales-Domínguez, D.J. Morán-Zenteno, W. Alvarez, P. Claeys, J. Ruíz-Morales, J. García-Hernández, P. Padilla-Avila, and A. Sánchez-Ríos. 2000. Chicxulub impact: The origin of reservoir and seal facies in the southeastern Mexico oil fields. Geology 28:307–310, https://doi.org/10.1130/0091-​7613(2000)28<307:CITOOR>2.0.CO;2.

Hart, M.B., T.E. Yancey, A.D. Leighton, B. Miller, C. Liu, C.W. Smart, and R.J. Twitchett. 2012. The Cretaceous-Paleogene boundary on the Brazos River, Texas: New stratigraphic sections and revised interpretations. GCAGS Journal 1:69–80.

Harwood, D.M. 1988. Upper Cretaceous and lower Paleocene diatom and silicoflagellate biostratigraphy of Seymour Island, eastern Antarctic Peninsula. Geological Society of America Memoirs 169:55–130, https://doi.org/10.1130/MEM169-p55.

Henehan, M.J., P.M. Hull, D.E. Penman, J.W. Rae, and D.N. Schmidt. 2016. Biogeochemical significance of pelagic ecosystem function: An end-Cretaceous case study. Philosophical Transactions of the Royal Society B 371(1694), https://doi.org/10.1098/rstb.2015.0510.

Hildebrand, A.R., G.T. Penfield, D.A. Kring, M. Pilkington, A.Z. Camargo, S.B. Jacobsen, and W.V. Boynton. 1991. Chicxulub Crater: A possible Cretaceous/Tertiary boundary impact crater on the Yucatán Peninsula, Mexico. Geology 19:867–871, https://doi.org/10.1130/0091-7613(1991)019​<0867:​CCAPCT>2.3.CO;2.

Hilting, A., L.R. Kump, and T.J. Bralower. 20078. Variations in the oceanic vertical carbon isotope gradient and their implications for the Paleocene-Eocene biological pump. Paleoceanography 23, PA3222, https://doi.org/10.1029/2007PA001458.

Hollis, C.J. 1997. Cretaceous-Paleocene radiolaria from eastern Marlborough, New Zealand. Institute of Geological & Nuclear Sciences Monograph 17:1–152.

Hollis, C.J., and C.P. Strong. 2003. Biostratigraphic review of the Cretaceous/Tertiary boundary transition, mid-Waipara river section, North Canterbury, New Zealand. New Zealand Journal of Geology and Geophysics 46(2):243–253, https://doi.org/​10.1080/00288306.2003.9515007.

Hollis, C.J., C.P. Strong, K.A. Rodgers, and K.M. Rogers. 2003. Paleoenvironmental changes across the Cretaceous/Tertiary boundary at Flaxbourne River and Woodside Creek, eastern Marlborough, New Zealand. New Zealand Journal of Geology and Geophysics 46:177–197.

Hsü, K.J., and J.A. McKenzie. 1985. A “Strangelove” ocean in the earliest Tertiary. Pp. 487–492 in The Carbon Cycle and Atmospheric CO: Natural Variations Archean to Present. AGU Geophysical Monograph Series, vol. 32, E.T. Sundquist and W.S. Broecker, eds, https://doi.org/10.1029/GM032p0487.

Huber, B.T., R.W. Hobbs, K.A. Bogus, and the Expedition 369 Scientists. 2018. Expedition 369 Preliminary Report: Australia Cretaceous Climate and Tectonics. International Ocean Discovery Program, https://doi.org/10.14379/iodp.pr.369.2018.

Hull, P.M., and R.D. Norris. 2011. Diverse patterns of ocean export productivity change across the Cretaceous-Paleogene boundary: New insights from biogenic barium. Paleoceanography 26(3), https://doi.org/10.1029/2010PA002082.

Hull, P.M., R.D. Norris, T.J. Bralower, and J.D. Schueth. 2011. A role for chance in marine recovery from the end-Cretaceous extinction. Nature Geoscience 4:856–860, https://doi.org/10.1038/ngeo1302.

Jiang, M.J., and S. Gartner. 1986. Calcareous nannofossil succession across the Cretaceous/Tertiary boundary in east-central Texas. Micropaleontology 32(3):232–255, https://doi.org/​10.2307/1485619.

Jiang, S., T.J. Bralower, M.E. Patzkowsky, L.R. Kump, and J.D. Schueth. 2010. Geographic controls on nannoplankton extinction across the Cretaceous/Palaeogene boundary. Nature Geoscience 3:280–285, https://doi.org/10.1038/ngeo775.

Kamo, S.L., C. Lana, and J.V. Morgan. 2011. U-Pb ages of shocked zircon grains link distal K-Pg boundary sites in Spain and Italy with the Chicxulub impact. Earth and Planetary Science Letters 310:401–408, https://doi.org/10.1016/j.epsl.2011.08.031.

Kasting, J.F. 1993. Earth’s early atmosphere. Science 259:920–926, https://doi.org/10.1126/science.11536547.

Keller, G. 1986. Stepwise mass extinctions and impact events: Late Eocene to Early Oligocene. Marine Micropaleontology 10:267–293. https://doi.org/​10.1016/0377-8398(86)90032-0.

Keller, G., T. Adatte, W. Stinnesbeck, M. Rebolledo-Vieyra, J. Urrutia-Fucugauchi, U. Kramar, and D. Stüben. 2004. Chicxulub impact predates the K-T boundary mass extinction. Proceedings of the National Academy of Sciences of the United States of America 101:3,753–3,758, https://doi.org/10.1073/pnas.0400396101.

Keller, G., T. Adatte, Z. Berner, M. Harting, G. Baum, M. Prauss, A. Tantawy, and D. Stueben. 2007. Chicxulub impact predates K-T boundary: New evidence from Brazos, Texas. Earth and Planetary Science Letters 255:339–356, https://doi.org/​10.1016/j.epsl.2006.12.026.

Keller, G., P. Mateo, J. Punekar, H. Khozyem, B. Gertsch, J. Spangenberg, A.M. Bitchong, and T. Adatte. 2018. Environmental changes during the Cretaceous-Paleogene mass extinction and Paleocene-Eocene Thermal Maximum: Implications for the Anthropocene. Gondwana Research 56:69–89, https://doi.org/10.1016/​j.gr.2017.12.002.

Kennett, D.J., J.P. Kennett, A. West, C. Mercer, S.Q. Hee, L. Bement, T.E. Bunch, M. Sellers, and W.S. Wolbach. 2009. Nanodiamonds in the Younger Dryas boundary sediment layer. Science 323:94, https://doi.org/10.1126/science.1162819.

Kirchner, J.W., and A. Weil. 2000. Delayed biological recovery from extinctions throughout the fossil record. Nature 404:177–180, https://doi.org/​10.1038/35004564.

Klaus, A., R.D. Norris, D. Kroon, and J. Smit. 2000. Impact-induced mass wasting at the K-T boundary: Blake Nose, western North Atlantic. Geology 28:319–322, https://doi.org/​10.1130/​0091-7613​(2000)28​<319:IMWATK>​2.0.CO;2.

Koeberl, C. 1998. Identification of meteoritic component in impactites. Pp. 133–153 in Meteorites: Flux with Time and Impact Effects. M.M. Grady, R. Hutchinson, G.J.H. McCall, and R.A. Rothery, eds, The Geological Society, London.

Koeberl, C., B. Milkereit, J.T. Overpeck, C.A. Scholz, P.Y.O. Amoako, D. Boamah, S. Danuor, T. Karp, J. Jueck, R.E. Hecky, and others. 2007. An international and multidisciplinary drilling project into a young complex impact structure: The 2004 ICDP Bosumtwi impact crater, Ghana, drilling project: An overview. Meteoritics and Planetary Science 42:483–511, https://doi.org/​10.1111/​j.1945-5100.2007.tb01057.x.

Koutsoukos, E.A.M. 2014. Phenotypic plasticity, speciation, and phylogeny in Early Danian planktic foraminifera. Journal of Foraminiferal Research 44:109–142, https://doi.org/10.2113/gsjfr.44.2.109.

Kring, D.A. 2000. Impact events and their effect on the origin, evolution, and distribution of life. GSA Today 10:1–7.

Kring, D.A. 2003. Environmental consequences of impact cratering events as a function of ambient conditions on Earth. Astrobiology 3:133–152, https://doi.org/10.1089/153110703321632471.

Kring, D.A., P. Claeys, S.P.S. Gulick, J.V. Morgan, G.S. Collins, and the IODP-ICDP Expedition 364 Science Party. 2017. Chicxulub and the exploration of large peak-ring impact craters through scientific drilling. GSA Today 27:4–8, https://doi.org/10.1130/GSATG352A.1.

Krogh, T.E., S.L. Kamo, and B.F. Bohor. 1993. U-Pb ages of single shocked zircons linking distal K/T ejecta to the Chicxulub crater. Nature 366:731–734, https://doi.org/10.1038/366731a0.

Kyte, F.T., J. Smit, and J.T. Wasson. 1985. Siderophile inter-element variation in the Cretaceous-Tertiary boundary sediments from Caravaca, Spain. Earth and Planetary Science Letters 73:183–195, https://doi.org/10.1016/0012-821X(85)90067-6.

Kyte, F.T., and J. Smit. 1986. Regional variations in spinel compositions: An important key to the Cretaceous/Tertiary event. Geology 14:485–487, https://doi.org/10.1130/0091-7613(1986)14​<485:RVISCA>2.0.CO;2.

Kyte, F.T., and J.A. Bostwick. 1995. Magnesioferrite spinel in Cretaceous/Tertiary boundary sediments of the Pacific basin: Remnants of hot, early ejecta from the Chicxulub impact? Earth and Planetary Science Letters 132:113–127, https://doi.org/​10.1016/​0012-821X(95)00051-D.

Kyte, F.T. 1998. A meteorite from the Cretaceous/Tertiary boundary. Nature 396(6708):237–239, https://doi.org/10.1038/24322.

Kyte, F.T. 2004. Primary mineralogical and chemical characteristics of the major K/T and Late Eocene impact deposits. American Geophysical Union Fall Meeting, abstract #B33C-0272.

Li, L., and G. Keller. 1998. Abrupt deep-sea warming at the end of the Cretaceous, Geology 26(11):995–998, https://doi.org/10.1130/​0091-​7613(1998)026​<0995:ADSWAT>​2.3.CO;2.

Liu, S., B.P. Glass, F.T. Kyte, and 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, GSA Special Paper 452, 37-70, https://doi.org/​10.1130/​2009.2452(04).

Lowery, C.M., T.J. Bralower, J.D. Owens, F.J. Rodríguez-Tovar, H. Jones, J. Smit, M.T. Whalen, P. Claeys, K. Farley, S.P.S. Gulick, and others. 2018. Rapid recovery of life at ground zero of the end Cretaceous mass extinction. Nature 558:288–291, https://doi.org/10.1038/s41586-018-0163-6.

Lowery, C.M., and A.J. Fraass. 2018. Explanation for delayed recovery of species diversity following the end Cretaceous mass extinction. PaleorXiv Papers, https://doi.org/10.31233/osf.io/wn8g6.

Luck, J.M., and K.K. Turekian. 1983. Osmium-187/Osmium-186 in manganese nodules and the Cretaceous-Tertiary boundary. Science 222:613–615, https://doi.org/10.1126/science.222.4624.613.

Luterbacher, H.P, and I. Premoli Silva. 1964. Biostratigrafia del limite Cretaceo-Terziario nell’Apennino Centrale. Rivista Italiana di Paleontologia 70:67–128.

MacLeod, N., P. Rawson, P. Forey, F. Banner, M. Boudagher-Fadel, P. Bown, J. Burnett, P. Chambers, S. Culver, S. Evans, and others. 1997. The Cretaceous-Tertiary biotic transition. Journal of the Geological Society 154:265–292, https://doi.org/​10.1144/gsjgs.154.2.0265.

MacLeod, K.G., D.L. Whitney, B.T. Huber, and C. Koeberl. 2007. Impact and extinction in remarkably complete Cretaceous-Tertiary boundary sections from Demerara Rise, tropical western North Atlantic. Geological Society of America Bulletin 119:101–115, https://doi.org/10.1130/B25955.1.

Mateo, P., G. Keller, J. Punekar, and J.E. Spangenberg. 2017. Early to Late Maastrichtian environmental changes in the Indian Ocean compared with Tethys and South Atlantic. Palaeogeography, Palaeoclimatology, Palaeoecology 478:121–138, https://doi.org/10.1016/j.palaeo.2017.01.027.

McDonald, M.A., H.J. Melosh, and S.P.S. Gulick. 2008. Oblique impacts and peak ring position: Venus and Chicxulub. Geophysical Research Letters 35, L07203, https://doi.org/10.1029/2008GL033346.

Meisel, T., U. Kraehenbuehl, and M.A. Nazarov. 1995. Combined osmium and strontium isotopic study of the Cretaceous-Tertiary boundary at Sumbar, Turkmenistan: A test for an impact versus a volcanic hypothesis. Geology 23(4):313–316, https://doi.org/10.1130/0091-7613(1995)023​<0313:COASIS>2.3.CO;2.

Melles, M., J. Brigham-Grette, P.S. Minyuk, N.R. Nowaczyk, V. Wennrich, R.M. DeConto, P.M. Anderson, A.A. Andreev, A. Coletti, T.L. Cook, and others. 2012. 2.8 million years of Arctic climate change from Lake El’gygytgyn, NE Russia. Science 337:315–320, https://doi.org/10.1126/science.1222135.

Melosh, H.J. 1977. Crater modification by gravity: A mechanical analysis of slumping. Pp. 76–78 in Impact and Explosion Cratering: Planetary and Terrestrial Implications. D.J. Roddy, R.O. Pepin, and R.B. Merrill, eds, Proceedings of the Symposium on Planetary Cratering Mechanics, Flagstaff, AZ, September 13–17, 1976, Pergamon Press.

Melosh, H.J., N.M. Schneider, K.J. Zahnle, and D. Latham. 1990. Ignition of global wildfires at the Cretaceous-Tertiary boundary. Nature 343:251–254, https://doi.org/​10.1038/​343251a0.

Meredith, R.W., J.E. Janecka, J. Gatesy, O.A. Ryder, C.A. Fisher, E.C. Teeling, A. Goodbla, E. Elzirik, T.L.L. Simão, T. Stadler, and others. 2011. Impacts of the Cretaceous terrestrial revolution and KPg extinction on mammal diversification. Science 334(6055):521–524, https://doi.org/10.1126/science.1211028.

Montanari, A., R.L. Hay, W. Alvarez, F. Asaro, H.V. Michel, L.W. Alvarez, and J. Smit. 1983. Spheroids at the Cretaceous-Tertiary boundary are altered impact droplets of basaltic composition. Geology 11:668­–671, https://doi.org/10.1130/0091-7613(1983)11​<668:SATCBA>2.0.CO;2.

Montanari, A., F. Asaro, H.V. Michel, and J.P. Kennett. 1993. Iridium anomalies of late Eocene age at Massignano (Italy), and ODP site 689B (Maud Rise, Antarctic). Palaios 8:420–437.

Montanari, A., and C. Koeberl. 2000. Impact Stratigraphy: The Italian Record. Lecture Notes in Earth Sciences, vol. 93, Springer-Verlag, Berlin, 364 pp.

Morgan, J., M. Warner, J. Brittan, R. Buffler, A. Camargo, G. Christeson, P. Denton, A. Hildebrand, R. Hobbs, H. Macintyre, and others. 1997. Size and morphology of the Chicxulub impact crater. Nature 390:472–476, https://doi.org/​10.1038/37291.

Morgan, J., and M. Warner. 1999. Chicxulub: The third dimension of a multi-ring impact basin. Geology 27:407–410, https://doi.org/10.1130/0091-​7613(1999)027<0407:CTTDOA>2.3.CO;2.

Morgan J.V., C. Lana, A. Kearsley, B. Coles, C. Belcher, S. Montanari, E. Díaz-Martínez, A. Barbosa, and V. Neumann. 2006. Analyses of shocked quartz at the global K–P boundary indicate an origin from a single, high-angle, oblique impact at Chicxulub. Earth and Planetary Science Letters 251:264–279, https://doi.org/10.1016/j.epsl.2006.09.009.

Morgan, J.V. 2008. Comment on “Determining chondritic impactor size from the marine osmium isotope record.” Science 321:1158, https://doi.org/​10.1126/science.1159174.

Morgan, J.V., M.R. Warner, G.S. Collins, R.A.F. Grieve, G.L. Christeson, S.P.S. Gulick, and P.J. Barton. 2011. Full waveform tomographic images of the peak ring at the Chicxulub impact crater. Journal of Geophysical Research: Solid Earth 116, B06303, https://doi.org/10.1029/2010JB008015.

Morgan, J., N. Artemieva, and T. Goldin. 2013. Revisiting wildfires at the K-Pg boundary. Journal of Geophysical Research 118(4):1,508–1,520, https://doi.org/10.1002/2013JG002428.

Morgan, J.V., S.P.S. Gulick, T. Bralower, E. Chenot, G. Christeson, P. Claeys, C. Cockell, G.S. Collins, M.J.L. Coolen, L. Ferrière, and others. 2016. The formation of peak rings in large impact craters. Science 354:878–882, https://doi.org/10.1126/​science.​aah6561.

Morgan, J.V., S.P.S. Gulick, C.L. Mellet, S.L. Green, and Expedition 364 Scientists. 2017. Chicxulub: Drilling the K-Pg Impact Crater, Proceedings of the International Ocean Discovery Program, 364. International Ocean Discovery Program, College Station, TX, https://doi.org/10.14379/​iodp.proc.364.2017.

Murray, J.B. 1980. Oscillating peak model of basin and crater formation. The Moon and the Planets 22:269–291, https://doi.org/10.1007/BF01259285.

Nisbet, E.G., and N.H. Sleep. 2001. The habitat and nature of early life. Nature 409:1,083–1,091, https://doi.org/10.1038/35059210.

Norris, R.D., J. Firth, J.S. Blusztajn, and G. Ravizza. 2000. Mass failure of the North Atlantic margin triggered by the Cretaceous-Paleogene bolide impact. Geology 28:1,119–1,122, https://doi.org/10.1130/0091-7613(2000)28​<1119:MFOTNA>2.0.CO;2.

Officer, C.B., and C.L. Drake. 1985. Terminal Cretaceous environmental events. Science 227:1,161–1,167, https://doi.org/10.1126/science.227.4691.1161.

Orth, C.J., J.S. Gilmore, J.D. Knight, C.L. Pillmore, R.H. Tschudy, and J.E. Fassett. 1981. An iridium abundance anomaly at the palynological Cretaceous-Tertiary boundary in northern New Mexico. Science 214:1,341–1,343, https://doi.org/​10.1126/​science.214.4527.1341.

Paquay, F.S., G.E. Ravizza, T.K. Dalai, and B. Peucker-Ehrenbrink. 2008. Determining chondritic impactor size from the marine osmium isotope record. Science 320:214–218, https://doi.org/10.1126/science.1152860.

Paquay, F.S., S. Goderis, G. Ravizza, F. Vanhaeck, M. Boyd, T.A. Surovell, V.T. Holliday, C.V. Haynes Jr., and P. Claeys. 2009. Absence of geochemical evidence for an impact event at the Bølling–Allerød/Younger Dryas transition. Proceedings of the National Academy of Sciences of the United States of America 106:21,505–21,510, https://doi.org/​10.1073/pnas.0908874106.

Pegram, W.J., S. Krishnaswami, G.E. Ravizza, and K.K. Turekian. 1992. The record of sea water 187Os/186Os variation through the Cenozoic. Earth and Planetary Science Letters 113:569–576, https://doi.org/10.1016/0012-821X(92)90132-F.

Penfield, G.T., and A. Camargo-Zanoguera. 1981. Definition of a major igneous zone in the central Yucatan platform with aeromagnetics and gravity. P. 37 in Technical Program, Abstracts and Bibliographies, 51st Annual Meeting, Society of Exploration Geophysicists, Tulsa, OK.

Perch-Nielsen, K. 1977. Albian to Pleistocene calcareous nannofossils from the western South Atlantic, DSDP Leg 39. Pp. 699–823 in Initial Reports of the Deep Sea Drilling Project, vol. 39. P.R. Supko, K. Perch-Nielsen, and others, eds, US Government Printing Office, Washington, DC, https://doi.org/​10.2973/dsdp.proc.39.131.1977.

Perch-Nielsen, K., J. McKenzie, and Q. He. 1982. Biostratigraphy and isotope stratigraphy and the ‘catastrophic’ extinction of calcareous nannoplankton at the Cretaceous/Tertiary boundary. Pp. 353–371 in Geological Implications of Impacts of Large Asteroids and Comets on the Earth. L.T. Silver and P.H. Schultz, eds, GSA Special Paper, vol. 190, https://doi.org/10.1130/SPE190-p353.

Percival, S.F., and A.G. Fischer. 1977. Changes in calcareous nanno-plankton in the Cretaceous-Tertiary biotic crisis at Zumay, Spain. Evolutionary Theory 2:1–35.

Peucker-Ehrenbrink, B., and G. Ravizza. 2000. The marine osmium isotope record. Terra Nova 12:205–219, https://doi.org/​10.1046/j.1365-3121.2000.00295.x.

Peucker-Ehrenbrink, B., and G. Ravizza. 2012. Osmium isotope stratigraphy. Pp. 145–166 in The Geologic Time Scale. F.M. Gradstein, J.G. Ogg, M.D. Schmitz, and G.M. Ogg, eds, Elsevier, https://doi.org/10.1016/B978-0-444-59425-9.00008-1.

Poag, C.W., D.S. Powars, L.J. Poppe, and R.B. Mixon. 1994. Meteoroid mayhem in Ole Virginny: Source of the North American tektite strewn field. Geology 22:691–694, https://doi.org/10.1130/0091-7613(1994)022<0691:​MMIOVS>2.3.CO;2.

Poirier, A., and C. Hillaire-Marcel. 2009. Os-isotope insights into major environmental changes of the Arctic Ocean during the Cenozoic. Geophysical Research Letters 36, https://doi.org/​10.1029/2009GL037422.

Poirier, A., and C. Hillaire-Marcel. 2011. Improved Os-isotope stratigraphy of the Arctic Ocean. Geophysical Research Letters 38, L14607, https://doi.org/10.1029/2011GL047953.

Pollastro, R.M., and B.F. Bohor. 1993. Origin and clay-mineral genesis of the Cretaceous-Tertiary boundary unit, western interior of North America. Clays and Clay Minerals 41:7–25, https://doi.org/​10.1346/CCMN.1993.0410102.

Pospichal, J.J., and S.W. Wise. 1990. Paleocene to Middle Eocene calcareous nannofossils of ODP Sites 689 and 690, Maud Rise, Weddell Sea. Pp. 613–638 in Proceedings of the Ocean Drilling Program, Scientific Results, vol. 113, #37, College Station, TX.

Premoli Silva, I., and H. Bolli. 1973. Late Cretaceous to Eocene planktonic foraminifera, and stratigraphy of Leg 15. Pp. 499–547 in Initial reports of the Deep Sea Drilling Project, vol. 15, Government Printing Office, Washington, DC.

Punekar, J., P. Mateo, and G. Keller. 2014. Effects of Deccan volcanism on paleoenvironment and planktic foraminifera: A global survey. Geological Society of America Special Papers 505:91–116, https://doi.org/​10.1130/2014.2505(04).

Pospichal, J.J., and T.J. Bralower. 1992. Calcareous nannofossils across the Cretaceous/Tertiary boundary, Site 761, northwest Australian margin. Pp. 735–751 in Proceedings of the Ocean Drilling Program, Scientific Results 122.

Rampino, M.R., and R.B. Stothers. 1984. Terrestrial mass extinctions, cometary impacts and the Sun’s motion perpendicular to the galactic plane. Nature 308:709–712, https://doi.org/​10.1038/308709a0.

Raup, D.M., and J.J. Sepkoski. 1982. Mass extinctions in the marine fossil record. Science 215:1,501–1,503, https://doi.org/10.1126/science.215.4539.1501.

Ravizza, G., J. Blusztajn, and H.M. Prichard. 2001. Re–Os systematics and platinum-group element distribution in metalliferous sediments from the Troodos ophiolite. Earth and Planetary Science Letters 188:369–381, https://doi.org/10.1016/S0012-821X(01)00337-5.

Reimold, W.U., L. Ferrière, A. Deutsch, and C. Koeberl. 2014. Impact controversies: Impact recognition criteria and related issues. Meteoritics and Planetary Science 49:723–731, https://doi.org/10.1111/maps.12284.

Renne, P.R., A.L. Deino, F.J. Hilgen, K.F. Kuiper, D.F. Mark, W.S. Mitchell, L.E. Morgan, R. Mundil, and J. Smit. 2013. Time scales of critical events around the Cretaceous-Paleogene boundary. Science 339:684–687, https://doi.org/10.1126/science.1230492.

Renne, P.R., I. Arenillas, J.A. Arz, V. Vajda, V. Gilabert, and H.D. Bermúdez. 2018. Multi-proxy record of the Chicxulub impact at the Cretaceous-Paleogene boundary from Gorgonilla Island, Colombia. Geology 46:547–550, https://doi.org/10.1130/G40224.1.

Riller, U., M.H. Poelchau, A.S.P. Rae, F.M. Schulte, G.S. Collins, H.J. Melosh, R.A.F. Grieve, J.V. Morgan, S.P.S. Gulick, J. Lofti, and others. 2018. Rock fluidization during peak ring formation of large impact craters. Nature 562:511–518, https://doi.org/10.1038/s41586-018-0607-z.

Robin, E., D. Boclet, P. Bonte, L. Froget, C. Jehanno, and R. Rocchia. 1991. The stratigraphic distribution of Ni-rich spinels in the Cretaceous-Tertiary boundary rocks at El Kef (Tunisia), Caravaca (Spain) and Hole 761C (Leg 122). Earth and Planetary Science Letters 107:715–721, https://doi.org/​10.1016/​0012-821X(91)90113-V.

Robinson, N., G. Ravizza, R. Coccioni, B. Peucker-Ehrenbrink, and R. Norris. 2009. A high-resolution marine 187Os/188Os record for the late Maastrichtian: Distinguishing the chemical fingerprints of Deccan volcanism and the KP impact event. Earth and Planetary Science Letters 281:159–168, https://doi.org/​10.1016/​j.epsl.2009.02.019.

Rocchia, R., D. Boclet, P. Bonte, L. Froget, B. Galbrun, C. Jehanno, and E. Robin. 1992. Iridium and other element distributions, mineralogy, and magnetostratigraphy near the Cretaceous/Tertiary boundary in Hole 761C. Pp. 753–762 in Proceedings of the Ocean Drilling Program, Scientific Results, vol. 122, College Station, TX.

Rocchia, R., E. Robin, L. Froget, and J. Gayraud. 1996. Stratigraphic distribution of extraterrestrial markers at the Cretaceous/Tertiary boundary in the Gulf of Mexico area: Implications for the temporal complexity of the event. Pp. 279–286 in The Cretaceous-Tertiary Boundary Event and Other Catastrophes in Earth History. G. Ryder, D. Fastovsky, and S. Gartner, eds, Geological Society of America Special Paper, vol. 307, Boulder, Colorado, https://doi.org/​10.1130/0-8137-2307-8.279.

Röhl, U., J.G. Ogg, T.L. Geib, and G. Wefer. 2001. Astronomical calibration of the Danian time scale. Pp. 163–183 in Western North Atlantic Palaeogene and Cretaceous Palaeoceanography. D. Kroon, R.D. Norris, and A. Klaus, eds, The Geological Society, London, Special Publications, vol. 183, https://doi.org/10.1144/GSL.SP.2001.183.01.09.

Romein, A. 1977. Calcareous nannofossils from Cretaceous-Tertiary boundary interval in Barranco del Gredero (Caravaca, Prov-Murcia, SE Spain). Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen Series B-Palaeontology Geology Physics Chemistry Anthropology 80:256.

Sanfilippo, A., W.R. Riedel, B.P. Glass, and F.T. Kyte. 1985. Late Eocene microtektites and radiolarian extinctions on Barbados. Nature 314:613–615, https://doi.org/10.1038/314613a0.

Sanford, J.C., J.W. Snedden, and S.P.S. Gulick. 2016. The Cretaceous-Paleogene boundary deposit in the Gulf of Mexico: Large-scale oceanic basin response to the Chicxulub impact. Journal of Geophysical Research 121:1,240–1,261, https://doi.org/​10.1002/2015JB012615.

Sato, H., T. Onoue, T. Nozaki, and K. Suzuki. 2013. Osmium isotope evidence for a large Late Triassic impact event. Nature Communications 4, 2455. https://doi.org/10.1038/ncomms3455.

Schaller, M.F., M.K. Fung, J.D. Wright, M.E. Katz, and D.V. Kent. 2016. Impact ejecta at the Paleocene-Eocene boundary. Science 354:225–229, https://doi.org/10.1126/science.aaf5466.

Schaller, M.F., and M.K. Fung. 2018. The extraterrestrial impact evidence at the Palaeocene–Eocene boundary and sequence of environmental change on the continental shelf. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 376, 20170081, https://doi.org/​10.1098/rsta.2017.0081.

Schueth, J.D., T.J. Bralower, S. Jiang, and M.E. Patzkowsky. 2015. The role of regional survivor incumbency in the evolutionary recovery of calcareous nannoplankton from the Cretaceous/Paleogene (K/Pg) mass extinction. Paleobiology 41:661–679, https://doi.org/10.1017/pab.2015.28.

Schulte, P., A. Deutsch, T. Salge, J. Berndt, A. Kontny, K.G. MacLeod, R.D. Neuser, and S. Krumm. 2009. A dual-layer Chicxulub ejecta sequence with shocked carbonates from the Cretaceous–Paleogene (K–Pg) boundary, Demerara Rise, western Atlantic. Geochimica et Cosmochimica Acta 73:1,180–1,204, https://doi.org/10.1016/​j.gca.2008.11.011.

Schulte, P., L. Alegret, I. Arenillas, J.A. Arz, P.J. Barton, P.R. Bown, T.J. Bralower, G.L. Christeson, P. Claeys, C.S. Cokell, and others. 2010. The Chicxulub asteroid impact and mass extinction at the Cretaceous-Paleogene boundary. Science 327:1,214–1,218, https://doi.org/10.1126/science.1177265.

Schultz, P.H., and S. D’Hondt. 1996. Cretaceous-Tertiary (Chicxulub) impact angle and its consequences. Geology 24:963–967, https://doi.org/​10.1130/​0091-​7613​(1996)​024​<0963:​CTCIAA>​2.3.CO;2.

Scotese, C.R. 2008. The PALEOMAP Project PaleoAtlas for ArcGIS, version 2, Volume 2, Cretaceous Plate Tectonic, Paleogeographic, and Paleoclimatic Reconstructions, Maps 16–32. PALEOMAP Project, https://doi.org/10.13140/RG.2.1.2011.4162.

Shukolyukov, A., and G.W. Lugmair. 1998. Isotopic evidence for the Cretaceous-Tertiary impactor and its type. Science 282:927–929, https://doi.org/10.1126/science.282.5390.927.

Sigurdsson, H., S. D’Hondt, M.A. Arthur, T.J. Bralower, J.C. Zachos, M. van Fossen, and J.E. Channel. 1991. Glass from the Cretaceous/Tertiary boundary in Haiti. Nature 349:482–487, https://doi.org/​10.1038/349482a0.

Sigurdsson, H., R.M. Leckie, and G.D. Acton. 1997. Caribbean volcanism, Cretaceous/Tertiary impact, and ocean climate history: Synthesis of Leg 165. Pp. 377–400 in Proceedings of the Ocean Drilling Program Initial Reports, vol. 165, H. Sigurdsson, R.M. Leckie, G.D. Acton, et al., College Station, TX, https://doi.org/10.2973/odp.proc.ir.165.108.1997.

Smit, J., and J. Hertogen. 1980. An extraterrestrial event at the Cretaceous-Tertiary boundary. Nature 285:198–200, https://doi.org/​10.1038/​285198a0.

Smit, J. 1982. Extinction and evolution of planktonic foraminifera at the Cretaceous/Tertiary boundary after a major impact. Pp. 329–352 in Geological Implications of Impacts of Large Asteroids and Comets on the Earth. L.T. Silver and P.H. Schultz, eds, Geological Society of America Special Paper, vol. 190, https://doi.org/10.1130/SPE190.

Smit, J., and F.T. Kyte. 1984. Siderophile-rich magnetic spheroids from the Cretaceous-Tertiary boundary in Umbria, Italy. Nature 310:403–405, https://doi.org/​10.1038/310403a0.

Smit, J., and A.J.T. Romein. 1985. A sequence of events across the Cretaceous-Tertiary boundary. Earth and Planetary Science Letters 74:155–170.

Smit, J., W. Alvarez, A. Montanari, N.H.M. Swinburn, T.M. Van Kempen, G.T. Klaver, and W.J. Lustenhouwer. 1992. “Tektites” and microkrystites at the Cretaceous–Tertiary boundary: Two strewn fields, one crater? Pp. 87–100 in 22nd Lunar and Planetary Science Conference Abstracts, March 18–22, 1991, Houston, TX.

Smit, J. 1999. The global stratigraphy of the Cretaceous-Tertiary boundary impact ejecta. Annual Review of Earth and Planetary Sciences 27:75–113, https://doi.org/10.1146/​annurev.earth.27.1.75.

Swisher, C.C., J.M. Grajales-Nishimura, A. Montanari, S.V. Margolis, P. Claeys, W. Alvarez, P. Renne, E. Cedillo-Pardo, F.J-M.R. Maurrasse, G.H. Curtis, and others. 1992. Coeval 40Ar/39Ar ages of 65.0 million years ago from Chicxulub crater melt rock and Cretaceous-Tertiary boundary tektites. Science 257:954–958, https://doi.org/10.1126/science.257.5072.954.

Thierstein, H.R., and H. Okada. 1979. The Cretaceous/Tertiary boundary event in the North Atlantic. Pp. 601–616 in Initial Reports of the Deep Sea Drilling Project, vol. 43, College Station, TX.

Thierstein, H.R. 1982. Terminal Cretaceous plankton extinctions: A critical assessment. Pp. 385–399 in Geological Implications of Impacts of Large Asteroids and Comets on the Earth. L.T. Silver and P.H. Schultz, eds, Geological Society of America Special Paper, vol. 190.

Thierstein, H.R., F. Asaro, W.U. Ehrmann, B. Huber, H. Michel, H. Sakai, H., and B. Schmitz. 1991. The Cretaceous/Tertiary boundary at Site 738, Southern Kerguelen Plateau. Pp. 849–867 in Proceedings of the Ocean Drilling Program Scientific Results vol. 119, #47.

Turekian, K.K. 1982. Potential of 187Os/186Os as a cosmic versus terrestrial indicator in high iridium layers of sedimentary strata. Pp. 243–249 in Geological Implications of Impacts of Large Asteroids and Comets on the Earth. L.T. Silver and P.H. Schultz, eds, Geological Society of America Special Paper, vol. 190.

Turgeon, S.C., and R.A. Creaser. 2008. Cretaceous oceanic anoxic event 2 triggered by a massive magmatic episode. Nature 454:323–326, https://doi.org/10.1038/nature07076.

Tyrrell, T., A. Merico, and D.I.A. McKay. 2015. Severity of ocean acidification following the end-Cretaceous asteroid impact. Proceedings of the National Academy of Sciences of the United States of America 112:6,556–6,561, https://doi.org/10.1073/pnas.1418604112.

Urrutia-Fucugauchi, J., J. Morgan, D. Stöffler, and P. Claeys. 2004. The Chicxulub Scientific Drilling Project (CSDP). Meteoritics & Planetary Science 39:787–790, https://doi.org/​10.1111/​j.1945-5100.2004.tb00928.x.

Westerhold, T., U. Röhl, I. Raffi, E. Fornaciari, S. Monechi, V. Reale, J. Bowles, and H.F. Evans. 2008. Astronomical calibration of the Paleocene time. Palaeogeography, Palaeoclimatology, Palaeoecology 257(4):377–403, https://doi.org/​10.1016/j.palaeo.2007.09.016.

Whalen, M.T., S.P.S. Gulick, Z.F. Pearson, R.D. Norris, L. Perez-Cruz, and J. Urrutia-Fucugauchi. 2013. Annealing the Chicxulub impact: Paleogene Yucatán carbonate slope development in the Chicxulub impact basin, Mexico. Pp. 282–304 in Deposits, Architecture, and Controls of Carbonate Margin, Slope and Basinal Settings. K. Verwer, T.E. Playton, and P.M. Harris, eds, SEPM Special Publications, vol. 105, https://doi.org/10.2110/sepmsp.105.04.

Vellekoop, J., A. Sluijs, J. Smit, S. Schouten, J.W.H. Weijers, J.S. Sinninghe Damsté, and H. Brinkhuis. 2014. Rapid short-term cooling following the Chicxulub impact at the Cretaceous–Paleogene boundary. Proceedings of the National Academy of Sciences of the United States of America 111:7,537–7,541, https://doi.org/10.1073/pnas.1319253111.

Vonhof, H.B., and J. Smit. 1999. Late Eocene microkrystites and microtektites at Maud Rise (Ocean Drilling Project Hole 689B; Southern Ocean) suggest a global extension of the approximately 35.5 Ma Pacific impact ejecta strewn field. Meteoritics & Planetary Science 34:747–755, https://doi.org/10.1111/j.1945-5100.1999.tb01387.x.

Vonhof, H.B., J. Smit, H. Brinkhuis, A. Montanari, and A.J. Nederbragt. 2000. Global cooling accelerated by early late Eocene impacts? Geology 28:687–690, https://doi.org/10.1130/0091-7613(2000)28​<687:GCABEL>2.0.CO;2.

Zachos, J.C., M.A. Arthur, R.C. Thunell, D.F. Williams, and E.J. Tappa. 1985. Stable isotope and trace element geochemistry of carbonate sediments across the Cretaceous/Tertiary boundary at Deep Sea Drilling Site 577, Leg 86. Pp. 513–532 in Initial Reports of the Deep Sea Drilling Project vol. 86, G.R. Heath, L.H. Burckle, et al., US Government Printing Office, Washington, DC, https://doi.org/​10.2973/dsdp.proc.86.120.1985.

Zachos, J.C., M.A. Arthur, and W.E. Dean. 1989. Geochemical evidence for suppression of pelagic marine productivity at the Cretaceous/Tertiary boundary. Nature 337:61–64, https://doi.org/​10.1038/337061a0.