Oligocene sea-level falls recorded in mid-Pacific atoll and archipelagic apron settings

Drilling results from mid-Pacific atoll and archipelagic apron sites in the Line Islands and Marshall Islands provinces lead to the conclusion that Oligocene sea-level falls detected in Atlantic passive margin sequences are also recorded in a mid-plate-tectonic setting in the Pacific Basin. The mid-...

Full description

Saved in:
Bibliographic Details
Published in:Geology (Boulder) 1986-05, Vol.14 (5), p.392-395
Main Authors: Schlanger, S. O, Premoli Silva, I
Format: Article
Language:English
Subjects:
atolls
biostratigraphy
Cenozoic
Central Pacific
correlation
cyclic processes
depositional environment
Enewetak Atoll
Foraminifera
intraplate tectonics
Invertebrata
island arcs
Line Islands
Marine
marine sedimentation
marine sediments
Marshall Islands
microfossils
Micronesia
Oceania
Oligocene
Pacific Ocean
Paleogene
Polynesia
Protista
reefs
regression
sea-level changes
sedimentation
sediments
stratigraphy
Tertiary
transgression
turbidite
unconformities
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Drilling results from mid-Pacific atoll and archipelagic apron sites in the Line Islands and Marshall Islands provinces lead to the conclusion that Oligocene sea-level falls detected in Atlantic passive margin sequences are also recorded in a mid-plate-tectonic setting in the Pacific Basin. The mid-Pacific sea-level falls are recorded by (a) the presence of distinct, coarse-grained, graded beds of turbidite origin, rich in reef-derived skeletal debris of Oligocene, Eocene, and Cretaceous age, that were redeposited in deep-water archipelagic apron carbonate sequences of middle and late Oligocene age now flanking the atolls and (b) a marked stratigraphic hiatus and solution unconformity in the subsurface of Enewetak atoll which dates an Oligocene period of atoll emergence correlative with both the deposition of the turbidites and the coastal offlap events discerned in Atlantic passive margins. Correlation of the subsidence path of Enewetak atoll with the development of the Oligocene solution unconformity shows that ca. 30 Ma sea level was as much as 100 m lower than at present.
ISSN:0091-7613
1943-2682
DOI:10.1130/0091-7613(1986)14<392:OSFRIM>2.0.CO;2