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How complete are Cretaceous /Tertiary boundary sections? A chronostratigraphic estimate based on graphic correlation

1991; Geological Society of America; Volume: 103; Issue: 11 Linguagem: Inglês

10.1130/0016-7606(1991)103 2.3.co;2

1943-2674

Norman MacLeod, Gerta Keller,

Hydrocarbon exploration and reservoir analysis

Research Article| November 01, 1991 How complete are Cretaceous /Tertiary boundary sections? A chronostratigraphic estimate based on graphic correlation NORMAN MACLEOD; NORMAN MACLEOD 1Department of Geological and Geophysical Sciences, Princeton University, Princeton, New Jersey 08544 Search for other works by this author on: GSW Google Scholar GERTA KELLER GERTA KELLER 1Department of Geological and Geophysical Sciences, Princeton University, Princeton, New Jersey 08544 Search for other works by this author on: GSW Google Scholar Author and Article Information NORMAN MACLEOD 1Department of Geological and Geophysical Sciences, Princeton University, Princeton, New Jersey 08544 GERTA KELLER 1Department of Geological and Geophysical Sciences, Princeton University, Princeton, New Jersey 08544 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1991) 103 (11): 1439–1457. https://doi.org/10.1130/0016-7606(1991)103 2.3.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation NORMAN MACLEOD, GERTA KELLER; How complete are Cretaceous /Tertiary boundary sections? A chronostratigraphic estimate based on graphic correlation. GSA Bulletin 1991;; 103 (11): 1439–1457. doi: https://doi.org/10.1130/0016-7606(1991)103 2.3.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract Cogent interpretations of data bearing on the Cretaceous/Tertiary (K/T) extinction controversy depend on the existence of accurate chronostratigraphic models for the various K/T boundary sections. We have employed the graphic correlation technique to summarize biostratigraphic and lithostratigraphic data from 15 intensively sampled K/T boundary sections within a common chronostratigraphic model. Our results indicate that almost all of these sections, along with 13 additional boundary sections not used to construct the model, contain prolonged and in many cases multiple hiatuses. Of these 28 boundary sections, only six were found to contain a continuous record of sediment accumulation across the K/T boundary itself. These six K/T-complete sections are El Kef (Tunisia), Agost (Spain), Caravaca (Spain), and three sections along the Brazos River (Texas).A comparative analysis of hiatus distributions among these 28 K/T boundary sections also reveals the presence of systematic differences between continental-shelf and deep-sea depositional environments. The lower Danian interval immediately following the K/T boundary, and extending into biochronozones P0 and P1a, is typically missing from the deep sea, whereas boundary sections deposited in shallower middle-neritic to upper-slope environments are in most cases complete across the K/T boundary. These shallow, neritic boundary sections, however, are in many instances disrupted by hiatuses at the P0/P1a boundary and again in the upper part of Zone P1a. These differential patterns of hiatus distribution between deep-sea and continental-shelf depositional settings appear to be linked to sea-level fluctuations. Our data suggest that the apparently sudden mass extinction of planktonic Foraminifera and anomalies in the occurrence of geochemical tracers that are characteristic of the K/T boundary in deep-sea sections may be artifacts of a temporally incomplete deep-sea stratigraphic record. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.