Tectonic Evolution Of Syria Interpreted From Integrated Geophysical And Geological Analysis

Acknowledgments

Abstract

Using a variety of geophysical and geological data, the Phanerozoic tectonic evolution of Syria has been interpreted. The study is inspired by the diverse styles of tectonic deformation within Syria generated by long-lived proximity to active plate boundaries. The work is also relevant to hydrocarbon exploration. The availability of seismic reflection and refraction profiles, wells, and other resources made this research possible.

Three studies focused on specific areas of Syria are presented. The first is a seismic refraction interpretation along a north - south profile in eastern Syria. The results show that metamorphic basement depth (and hence Paleozoic thickness) in southeast Syria is greater, by >2 km, than that in the northeast.

The next study interprets the structure and tectonics in northeast Syria. During Late Paleozoic and Mesozoic time northeast Syria was an extension of the Palmyride trough. In the Maastrichtian, regional extension opened the Abd el Aziz and Sinjar graben that were structurally inverted in the Late Cenozoic to form the present topography.

The third study concerns the Ghab Basin in western Syria. This 3.4 km deep Plio-Quaternary pull-apart basin suggests that the Dead Sea Fault System has only been active in Syria since the end of the Miocene in accordance with a two-phase model of Red Sea opening.

The final study integrates the previous interpretations with new work to provide a tectonic evolutionary model that shows the Phanerozoic development of all Syria. This model is closely tied to stratigraphic data that improve the interpretation of many tectonic events, and put the results into a paleogeographical context. The model shows how specific deformation episodes within Syria have been penecontemporaneous with regional plate tectonic events. The Late Paleozoic / Mesozoic northeast trending Palmyride / Sinjar trough formed across central Syria in response to Permo-Triassic opening of the NeoTethys Ocean. Proximal subduction in the NeoTethys created the Late Cretaceous Euphrates Fault System and Abd el Aziz / Sinjar graben in eastern Syria. Late Cretaceous to Late Miocene collisions and shortening along the northern Arabian margin caused platform-wide structural inversion, uplift, and shortening. This compression continues today under the influence of Arabia / Eurasia convergence.

Biographic Sketch

Graham Brew was born in 1974 in Staffordshire, England, not far from the sprawling metropolis of Birmingham where he spent most of his childhood. Through family vacations and school trips he developed a love for the outdoors that still endures. Moreover, during his secondary schooling dedicated and devoted teachers instilled in Graham a passion for science, especially physics and geography. Combining these interests he enrolled as a geophysics major at University College, London. There he had the great fortune to work with many astute geoscientists who further kindled his love for earth science. One of his professors, John Milsom, was also instrumental in securing Graham a challenging and enlightening internship in Santiago, Chile, during the austral winter of 1994.

Upon deciding to continue his education, Graham applied to study geophysics at Cornell University. His application was intercepted by Muawia Barazangi, who, with higher wisdom, saw a vision of a budding research scientist. Thus Graham swapped the bright lights of London for the more relaxed, rustic charms of Ithaca, New York. We can now argue that Muawia's vision was correct. More than five years, and a great deal of lost sleep later, Graham looks ready to receive his doctorate.

For the short-term Graham will continue to live in Ithaca and work as a post-doctoral associate with Muawia. His wife, Chris, who somehow pried Graham away from seismic lines and Adobe Illustrator long enough to marry him, continues her graduate study in biochemistry. Once their time in Ithaca draws to a close, Graham and Chris will follow their joint love of science, but as yet they are not quite sure where.

List of Figures

Figure Number	Short Figure Caption
CHAPTER 1
Figure 1.1	Regional Tectonic Setting of Syria
Figure 1.2	Topography and reas investigated in this dissertation
CHAPTER 2
Figure 2.1	Regional Setting of Syria
Figure 2.2	Location of seismic refraction profile under analysis
Figure 2.3	Configuration of shots and spreads in refraction survey
Figure 2.4	Typical example of seismic refraction data
Figure 2.5	Sonic log and synthetic seismogram correlation
Figure 2.6	Correlation of refraction model with seismic reflection data
Figure 2.7	Final velocity model and correlation with deep well data
Figure 2.8	Examples of ray-tracing interpretation
Figure 2.9	Bouguer gravity anomalies near refraction profile and gravity models
Figure 2.10	Summary of known basement depths in Syria
CHAPTER 3
Figure 3.1	Topographic image of northeast Syria
Figure 3.2	Database map of resources in northeast Syria
Figure 3.3	Generalized stratigraphic column of northeast Syria
Figure 3.4	Depth converted seismic profile (DH-46)
Figure 3.5	Well correlation across Sinjar structure
Figure 3.6	Well correlation across Abd el Aziz structure
Figure 3.7	Subsidence curve from Sinjar area
Figure 3.8	Evolution of northeast Syria since the Early Paleozoic
Figure 3.9	Distribution of Paleozoic subcrops in northeast Syria
Figure 3.10	Migrated seismic section AB-06
Figure 3.11	Migrated seismic section SA-12
Figure 3.12	Enlarged portion of seismic profile DH-46
Figure 3.13	Composite of seismic reflection sections TSY-88-201 and TSY-90-201X
Figure 3.14	Structure map near top Lower Cretaceous horizon in northeast Syria
Figure 3.15	Structure map near Top Cretaceous horizon in northeast Syria
Figure 3.16	Seismic reflection profile across Abd el Aziz structure
Figure 3.17	Summary of the geologic evolution of Syria since the Late Paleozoic
CHAPTER 4
Figure 4.1	Topography of the Dead Sea Fault System
Figure 4.2	Shaded relief image of the Ghab Basin and surrounding areas
Figure 4.3	Geologic map of the Ghab Basin, Coastal Ranges, and surroundings
Figure 4.4	Seismic and gravity interpretation along the Ghab Basin
Figure 4.5	Seismic profile across the Ghab Basin
Figure 4.6	Seismic and gravity interpretation across the Ghab Basin and Coastal Ranges
Figure 4.7	Three-dimensional image of the Ghab Basin, subsurface and gravity
Figure 4.8	Comparison of Ghab Basin with other strike-slip basins and models
Figure 4.9	Profiles of topography at various points along the Dead Sea Fault System
Figure 4.10	Block model illustrating the evolution of the Coastal Ranges
Figure 4.11	Regional evolution of the Dead Sea Fault System
Figure 4.12	Evolution of the Ghab Basin
CHAPTER 5
Figure 5.1	Regional tectonic map of the Arabian Plate
Figure 5.2	Topographic map of Syria, and database used in this Chapter
Figure 5.3	Block model of the Abou Rabah structure in the western Palmyrides
Figure 5.4	Seismic reflection interpretation from the Bishri block
Figure 5.5	Block model of the Abd el Aziz area in northeast Syria
Figure 5.6	Block model of the Euphrates Graben System
Figure 5.7	block model of the Ghab Basin and Syrain Coastal Ranges
Figure 5.8	Generalized lithostratigraphic chart for all Syria
Figure 5.9	Isopachs of major sediment packages in Syria
Figure 5.10	3-D fence diagram showing sedimentary thickness variations
Figure 5.11	Structure maps on various horizons for all Syria
Figure 5.12	Perspective views of the structure of all Syria
Figure 5.13	Bouguer gravity map of Syria
Figure 5.14	Gravity models across the Palmyrides in central Syria
Figure 5.15	Chronological chart illustrating the relationships between tectonic and hydrocarbons
PLATE 1	New tectonic map of Syria
PLATE 2	Tectonic evolution of Syria

Acknowledgements

My first, and most earnest, acknowledgment must go to my advisor and chair of my Special Committee Muawia Barazangi. Nearly six years ago, a telephone conversation with Muawia started me on the path I traveled at Cornell. Muawia has been instrumental in ensuring my academic, professional, financial, and moral well being ever since. In every sense, none of this work would have been possible without him. Many thanks also to committee members Larry Brown and Wilfried Brutsaert.

Far too many people to mention individually have assisted in so many ways during my work at Cornell. They all have my sincere gratitude. In particular, I would like to thank Paco Gomez, Dogan Seber, Alex Calvert, Elias Gomez, Eric Sandvol, Bob Litak, Ali Al-Lazki, Khaled Al-Damegh, Steve Gallow, Terry Jordan, Ben Brooks, Don Turcotte, Rick Allemdinger, Carrie Brindisi, Christine Sandvol, Claire Burns, Steve Losh, Andy Ross, Jacek Lupa, Mahogany Paulino, Matt Recker, and Weldon Beauchamp, all currently, or previously, of Cornell University. I would also like to thank Alan Beck, Phil Lovelock, Martin Miller, Moujaheed Husseini, and several anonymous reviewers for their help and comments that improved various published papers.

I also owe a huge debt of gratitude to Khaled Al-Maleh, Mikhail Mouty, Abdul Nasser Darkal, and many other friends in Syria who were instrumental in the success of my recent visit to their enchanting country. Khaled deserves particular credit for introducing me to the nuances of Syrian lithostratigraphy. Mustapha Meghraoui, as well as being an expert paleoseismologist, is just fun to be around.

The data for this study were provided by the Syrian Petroleum Company (SPC). I am extremely grateful for this SPC generosity without which this dissertation would not have been possible. I also salute the intellectual input of many SPC scientists including Tarif Sawaf, Tarek Zaza, and Anwar Al-Imam.

This research was, at various times, supported by Alberta Energy Company International, Amoco, Arco, British Gas, Conoco, Exxon, Marathon, Mobil, Occidental, Sun International, and Unocal oil companies. I am also indebted to the Department of Geological Sciences at Cornell, Cornell University graduate school, Amoco oil company, the Society of Exploration Geophysicists, and the Bender family for direct financial aid through fellowships, awards, and travel grants. I also commend Landmark for the provision of their seismic interpretation software under their University Grant program.

A penultimate thank-you goes to my wonderful parents. For always being there when I needed them most, and never once complaining about how infrequently I visit, they deserve far more credit than I can ever give them.

My final, and most heartfelt, acknowledgment must go to my wife Christine. Chris has worked diligently, and successfully, for more than four years to show me life outside Snee Hall. Her support, encouragement, and companionship has turned my journey through graduate school into a pleasure. For all that, and for being everything I am not, she has my everlasting love.

http://atlas.geo.cornell.edu/people/brew/gbthesisintro.html

For questions or comments, please contact Muawia Barazangi: mb44@cornell.edu

Last updated: January 2001