Aptian-Albian eustatic sea-levels

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doi: 10.1002/9781444304879.ch6
Author(s): Röhl, U.; Ogg, J. G.
Author Affiliation(s): Primary:
Bremen University, Geosciences Division, Bremen, Federal Republic of Germany
University of Sydney, Australia
Purdue University, United States
Volume Title: Reefs and carbonate platforms in the Pacific and Indian oceans
Volume Author(s): Camoin, G. F., editor; Davies, P. J.
Source: Reefs and carbonate platforms in the Pacific and Indian oceans, edited by G. F. Camoin and P. J. Davies. Special Publication of the International Association of Sedimentologists, Vol.25, p.95-136. Publisher: Blackwell, Oxford, International. ISSN: 0141-3600. ISBN: 978-1-444-30487-9 CODEN: SPISDS
Note: In English. Includes appendix. 82 refs.; illus., incl. 2 tables, sketch map
Summary: Carbonate banks record rapid falls of relative sea-level as emergent surfaces and rapid rises as deepening or drowning events. During the combined Ocean Drilling Program Legs 143 and 144, four carbonate banks of Aptian-Albian age were drilled on top of seamounts ('guyots') that span a large region of the north-western Pacific. Simultaneous episodes of emergence ('sequence boundary') or deepening at these guyots must be the result of major eustatic sea-level events. From a combination of cored lithologies and downhole geophysical and geochemical logs we identified depositional sequences. A general geological age framework was assigned from biostratigraphical datum levels and chemo-stratigraphical (carbon and strontium isotope) curves. Compensation for thermal subsidence rates allowed assignment of relative durations of the array of sequences within each stage. The number of upward-shallowing cycles or parasequences was also used to compare relative durations of sequences among sites. These Pacific carbonate banks record 12 Aptian and 12 Albian significant shallowing events, of which a third were associated with major episodes of emergence. The major events on the guyots can be correlated easily with Aptian-Albian relative sea-level changes observed in European shelf successions, and both regions display the same number of minor events. Therefore, we can apply the relative timing of these events from the thermal subsidence compensation and parasequence counts within the Pacific banks to construct an improved scaling of the associated ammonite zones and biostratigraphical datum levels within the Aptian-Albian interval. Abstract Copyright (1998), International Association of Sedimentologists.
Year of Publication: 1998
Research Program: ODP Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Albian; Allison Seamount; Ammonites; Ammonoidea; Aptian; Biogenic structures; Biostratigraphy; Biozones; Carbonate banks; Carbonate platforms; Cephalopoda; Cores; Cretaceous; Downhole methods; Geophysical surveys; Invertebrata; Leg 143; Leg 144; Lower Cretaceous; MIT Seamount; Mesozoic; Mid-Pacific Mountains; Mollusca; North Pacific; ODP Site 865; ODP Site 866; ODP Site 878; ODP Site 879; Ocean Drilling Program; Ocean floors; Pacific Ocean; Resolution Seamount; Sea-level changes; Seamounts; Sedimentary structures; Sequence stratigraphy; Shallow-water environment; Surveys; Takuyo-Daisan Seamount; Tetrabranchiata; West Pacific
Record ID: 2001044113
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute.

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