Skip to Main Content
GEOREF RECORD

New technique for dating igneous sills

James Trude, Joe Cartwright, Richard J. Davies and John Smallwood
New technique for dating igneous sills
Geology (Boulder) (September 2003) 31 (9): 813-816

Abstract

Three-dimensional seismic interpretation of Tertiary sills within the northeast Atlantic margin demonstrates that shallow-level (<1 km) intrusion of igneous sills below the seafloor can deform the interface between water and sediment during its early burial stage by hydraulic elevation of the overburden. We show that a group of interconnected sills forcibly "jacked up" the seafloor, contributing to the creation of a minibasin 5 km wide, 250 m deep, and >20 km long. The fill of the minibasin is dated biostratigraphically as 54.6-55 Ma, which fits well with radiometric dates for the timing of intrusion of sills around this basin (ca. 53-55 Ma). The recognition and dating of onlap-fill seismic reflector packages that are delimited by forced folds form a new and useful method for dating shallow-level igneous intrusions in sedimentary basins, a method that provides independent constraints on radiometric dating techniques. Similar forced folds are recognized from other basins that have shallow-level sills, suggesting that the technique presented here may be similarly applicable in comparable geologic settings.


ISSN: 0091-7613
EISSN: 1943-2682
Coden: GLGYBA
Serial Title: Geology (Boulder)
Serial Volume: 31
Serial Issue: 9
Title: New technique for dating igneous sills
Affiliation: Cardiff University, School of Earth, Ocean, and Planetary Sciences, Cardiff, United Kingdom
Pages: 813-816
Published: 200309
Text Language: English
Publisher: Geological Society of America (GSA), Boulder, CO, United States
References: 26
Accession Number: 2003-063132
Categories: Igneous and metamorphic petrologyStratigraphy
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. sects., sketch maps
N51°30'00" - N51°49'60", W02°19'60" - W01°53'60"
Secondary Affiliation: Amerada Hess, GBR, United Kingdom
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute. Reference includes data supplied by the Geological Society of America, Boulder, CO, United States
Update Code: 200320
Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal