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Phanerozoic Cycles of Sealevel Change
GeoArabia is an international journal that publishes leading-edge Middle East petroleum geoscience studies. The journal is quarterly and printed in Bahrain as authorized by the Directorate of Public Relations, Ministry of Information, Kingdom of Bahrain. GeoArabia is registered with the Copyright Clearing Center, Boston, and indexed in GeoRef, the 'Bibliography and Index of Geology', produced by the American Geological Institute.
The website of the Geoarabia is: http://www.gulfpetrolink.net
The charts reproduced below on may not be reproduced, stored or transmitted, without written permission from Petrolink.
Abstract:
The purpose of this note is to present revisions to the SP2 scheme resulting either from significant errors in SP2 or from newly published data that challenges SP2, or from newly published data identifying maximum flooding surfaces.
The publication of Arabian Plate Sequence Stratigraphy (Sharland et al., 2001), commonly referred to as SP2, provided a unifying stratigraphic interpretation of the Arabian Plate within a modern sequence stratigraphic framework. In 2002 revisions to the stratigraphic positions of some SP2 Cretaceous maximum flooding surfaces (MSF), and some resulting new interpretations, were presented by Davies et al. (2002) . New interpretations of mixed carbonate-clastic systems presented by these authors have applications to other parts of Middle East stratigraphy.
Since 2001, many excellent new papers have been published, and oral presentations made, containing new data and/or interpretations (e.g. Al-Eidan et al., 2001; Brew et al., 2001; Konert et al., 2001; Ziegler, 2001; Al-Suwaidi and Aziz, 2002; Nehlig et al., 2002; van Buchem et al., 2002; Boote and Mou, 2003; Prince and Fell, 2003; Stephenson et al., 2003 - to name but a few). The interpretations presented here are based on this new post-SP2 literature, as well as re-interpretations of older literature in the light of this new work.
Following discussions with Gulf PetroLink, the Neftex SP2 authors have been encouraged to provide a summary chronostratigraphic up-date based on this new literature from GEO 2004 of the SP2 interpretation, with particular emphasis on (1) revisions to the published geological timescale; (2) changes to SP2 megasequence boundaries (position and dating); (3) changes to SP2 maximum flooding surfaces (position and dating); (4) the identification and dating of any new TMS and/or MFS; and (5) any proposed changes to the SP2 sequence stratigraphic nomenclature.
This GeoArabia Stratigraphic Note and the accompanying two chronostratigraphic chart enclosures (Enclosure 1 Mesozoic and Cenozoic, and Enclosure 2 Paleozoic and Precambrian), are intended to update those in SP2. These new charts have been extended into Jordan (in the north) and southwest Oman and Yemen (in the south). Significant changes to MFS are made in the Neogene, Paleogene and Permo-Triassic sections.
Geoarabia vol. 10, no. 2, 2005: 127-160, 2 charts
Abstract:
The Arabian Plate has experienced a complex tectonic history while also being
widely influenced by eustatic sea-level changes. These diastrophic events
either affected changes in the rate and/or location of subsidence that in turn
led to the creation of significant new sedimentary accommodation, or caused
major erosional hiatuses. As a result, both eustacy and tectonics have played
important roles in the development of sedimentary sequences and in determining
the locus and characteristics of reservoir, source and seal facies on the
Arabian Platform. Here, we present a synthesis (Cycle
Chart A and Cycle Chart B) of the regional sea-level fluctuations affecting the Platform that is based on Phanerozoic epi- and peri-Platform sequence-stratigraphic data. Information used for the synthesis includes sections from Saudi Arabia, Kuwait, the Greater Gulf are, Oman and Yemen. The regional Cycle Chart incorporates interpreted sedimentary onlap patterns on the margins of the Arabian Platform, as well as models of regional sea-level fluctuations that controlled these patterns. These are compared to eustatic data that represents the 'global mean' models of sea-level changes, largely at second-order cycle level for the Paleozoic and third-order cycle level for the Mesozoic and Cenozoic eras. The comparisons reveal that Phanerozoic sediment accumulation patterns on the Platform were broadly controlled by eustacy, with a strong overprint of tectonics for several long intervals. During periods of tectonic quiescence, however, correlations with the eustatic events improve significantly. Thus, for example, during the Cambrian through early Silurian and mid Jurassic through early Paleogene intervals eustacy may have been the significant controlling factor for sedimentary patterns when long-term trends in both regional and global sea-level curves show similarities.
The use of the Cycle Chart could facilitate exploration efforts on the Arabian Platform, provide better chronostratigraphic estimates and global correlations, and prove a useful accompaniment for sequence-stratigraphic studies. This interactive effort was greatly facilitated by the recent publication of the sequence-stratigraphic synthesis of the Arabian Plate. The ages of Maximum Flooding Surfaces, however, have been recalibrated to the new (GTS 2004) time scale. This synthesis also represents a new recalibration of the Mesozoic and Cenozoic eustatic curves of Haq et al. (1988) to an up-to-date numerical time scale (GTS 2004).
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