|
|
 |
|||||||||||||||||
|
|||||||||||||||||
 |
|||||||||||||||||
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |
1 3DLab, School of Earth, Ocean and Planetary Sciences, Main Building, Park Place, Cardiff University, Cardiff, CF10 3YE, United Kingdom; alvest{at}cardiff.ac.uk
2 3DLab, School of Earth, Ocean and Planetary Sciences, Main Building, Park Place, Cardiff University, Cardiff, CF10 3YE, United Kingdom
3 CeREES (Centre for Research into Earth Energy Systems), Department of Earth Sciences, Durham University Science Labs, Durham, DH1 3LE, United Kingdom
Tiago is a research lecturer at Cardiff University. After completing his Ph.D. in geology at the University of Manchester, he worked in Portugal and then Greece through the umbrella of European Union projects (EURODOM and HERMES) dedicated to the study of continental margins. His research interests include the study of deep-water rift basins and overlying postrift successions. He is particularly interested in investigating the way tectonics influences sedimentation using novel statistical methods, petrophysical, and 3-D seismic data.
Joe received his B.A. and D.Phil degrees in geology from Oxford University. He is a research professor of geophysics and the director of the 3-D Lab at Cardiff University. His research interests focus on 3-D seismic interpretation in basin analysis, with special emphasis on seal integrity analysis, the genesis of polygonal faults, the emplacement of sandstone and igneous intrusions, and silica diagenesis.
Richard is a professor of petroleum geoscience and the director for the Center for Research into Earth Energy Systems at Durham University. He was formerly at ExxonMobil for 8 years. He has published more than 40 articles on the use of 3-D seismic data for understanding sedimentary, fluid flow, structural, igneous, and diagenetic processes in basins.
ABSTRACT
Three-dimensional seismic-reflection data are used in the analysis of submarine channel systems in the Espírito Santo Basin, Brazil. The exceptional quality of the studied data set allows the detailed documentation of the geometry, regional distribution, and statistical parameters of salt-related normal faults, and their effect on the Rio Doce Canyon system (RDCS). On the Espírito Santo continental slope, normal faulting was triggered during early halokinesis (stage A) but barely controlled the initial evolution of the RDCS, which incised the continental slope axially within a salt-withdrawal basin. However, in a second stage (stage B), crestal or radial faults controlled erosion over growing salt structures, whereas synclinal and channel-margin fault sets dissected overbank strata to the RDCS. In the later part of stage B, channel sinuosity decreased sharply in response to fault activity and associated sea-floor destabilization. Vertical propagation of blind faults was triggered in a third stage (stage C), in association with crestal collapse of buried salt anticlines and regional diapirism, but synclinal and channel-margin faults did not propagate vertically above a regional unconformity marking the base of stage C strata. Statistical analyses of observed fault sets demonstrate that synclinal faults are in average 2.3 times longer than the crestal or radial types but record 60% of the throw (average 83 m [272 ft]) experienced by the latter. In addition, the fault sets are shown to have contributed to local cannibalization of the sea floor, vertical stacking of channel-fill strata, and structural and depositional compartmentalization of potential reservoir successions. As a result, channel systems show marked differences in mean values for sinuosity, height, and width in relation to five main phases of channel development. The structural setting in the study area differs from productive areas offshore Espírito Santo (e.g., Golfinho field), west Africa, and Gulf of Mexico, revealing in distal parts of the Brazilian margin the existence of local controls on submarine channel architecture and structural compartmentalization prior to the main stages of diapirism.
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |
