CaltechAUTHORS
  A Caltech Library Service

Evolution of the Malvinas Plate South of Africa

Marks, K. M. and Stock, J. M. (2001) Evolution of the Malvinas Plate South of Africa. Marine Geophysical Researches, 22 (4). pp. 289-302. ISSN 0025-3235 . https://resolver.caltech.edu/CaltechAUTHORS:20140416-090645328

Full text is not posted in this repository. Consult Related URLs below.

Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20140416-090645328

Abstract

We confirm that a Malvinas Plate is required in the Agulhas Basin during the Late Cretaceous because: (1) oblique Mercator plots of marine gravity show that fracture zones generated on the Agulhas rift, as well as the Agulhas Fracture Zone, do not lie on small circles about the 33o-28y South America-Africa stage pole and were therefore not formed by South America-Africa spreading, (2) the 33o-28y South America-Africa stage rotation does not bring 33o magnetic anomalies on the Malvinas Plate into alignment with their conjugates on the African Plate, and (3) errors in the 33o-28y South America-Africa stage rotation cannot account for the misalignment. We present improved Malvinas-Africa finite rotations determined by interpreting magnetic anomaly data in light of fracture zones and extinct spreading rift segments (the Agulhas rift) that are clearly revealed in satellite-derived marine gravity fields covering the Agulhas Basin. The tectonic history of the Malvinas Plate is chronicled through gravity field reconstructions that use the improved Malvinas-Africa finite rotations and more recent South America-Africa and Antarctica-Africa finite rotations. Newly-mapped triple junction traces on the Antarctic, South American, Malvinas, and African Plates, combined with geometric and magnetic constraints observed in the reconstructions, enable us to investigate the locations of the elusive western and southern boundaries of the Malvinas Plate.


Item Type:Article
Related URLs:
URLURL TypeDescription
http://link.springer.com/article/10.1023/A:1014638325616PublisherArticle
http://dx.doi.org/10.1023/A:1014638325616DOIArticle
ORCID:
AuthorORCID
Stock, J. M.0000-0003-4816-7865
Additional Information:© 2002 Kluwer Academic Publishers. Received 20 March 2001; accepted 2 October 2001. This revised version was published online in November 2006 with corrections to the Cover Date. The comments of two anonymous reviewers greatly improved this manuscript. We thank Steve Cande for digital magnetic anomaly identifications in the South Atlantic Ocean. J. Stock’s participation was supported by NSF grant OPP-9814579. California Institute of Technology, Division of Geological and Planetary Sciences, contribution 8839. Images of the reconstructions are available on the Worldwide Web site http://ibis.grdl.noaa.gov/SAT/kmm/pubs.kmm.html.
Group:Seismological Laboratory
Funders:
Funding AgencyGrant Number
NSFOPP-9814579
Subject Keywords:Agulhas Basin, gravity anomalies, Late Cretaceous, Malvinas Plate, plate tectonics, reconstruction, South Atlantic Ocean.
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Caltech Division of Geological and Planetary Sciences8839
Issue or Number:4
Record Number:CaltechAUTHORS:20140416-090645328
Persistent URL:https://resolver.caltech.edu/CaltechAUTHORS:20140416-090645328
Official Citation: Evolution of the Malvinas Plate South of Africa K.M. Marks, J.M. Stock Pages 289-302
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:44971
Collection:CaltechAUTHORS
Deposited By: Ruth Sustaita
Deposited On:16 Apr 2014 16:54
Last Modified:03 Oct 2019 06:24

Repository Staff Only: item control page