Regional Geology and Tectonics: Phanerozoic Rift Systems and Sedimentary Basins

David G. Roberts

• Publisher: Elsevier
• Year: 2012
• ISBN:
  9780444563637
• Topic: Physical Sciences
• Subtopic: Geology & Earth Sciences

Expert petroleum geologists David Roberts and Albert Bally bring you Regional Geology and Tectonics: Phanerozoic Rift Systems and Sedimentary Basins, volume two in a three-volume series covering Phanerozoic regional geology and tectonics. Experience in analyzing and assessing rifts—locations where the Earth's outer shell and crust have been stretched over time by seismic activity—is critical for you as an exploration geologist in identifying Earth's most lucrative hydrocarbon locations in which extraction is both efficient and safe. Vast compilations of related industry data present regional seismic lines and cross sections, and summaries of analogue and theoretical models are provided as an essential backdrop to the structure and stratigraphy of various geological settings.

• Named a 2013 Outstanding Academic Title by the American Library Association's Choice publication
• A practical reference for petroleum geologists that discusses the importance of rift systems and the structural evolution of the Earth
• Analyses of active rifts in East Africa, China, Siberia, the Gulf of Suez, and the Russian Arctic provide immediately implementable petroleum exploration applications in regions heavily targeted by oil & gas companies
• Presents overviews of sequence stratigraphy in rifts and structural controls on clastic and carbonate sedimentation—critical to the exact mapping of the most lucrative hydrocarbon locations by exploration geologists

SECTION 1

Rift Systems

Chapter 1 Regional geology and tectonics of sedimentary basins

Chapter 2 From rifts to passive margins

Chapter 3 Models for the evolution of passive margins

Chapter 4 Rift sequence stratigraphy

Chapter 5 Structural control on syn-rift sedimentation, northwestern Red Sea margin, Egypt

Chapter 6 Carbonate-dominated marine rifts

1

Regional geology and tectonics of sedimentary basins

A Prologue

D.G. Roberts^* and A.W. Bally^†

^*Department of Earth Sciences, Royal Holloway, University of London, Egham, Surrey, United Kingdom

^†Department of Earth Sciences, Rice University, Houston, Texas, USA

In this chapter

1.1 Introduction

1.2 A historical perspective

1.3 Some remarks on regional geology and tectonics

1.4 Conclusion

References

1.1 Introduction

Regional geology forms an essential bridge between local and continental/global geology. Its purpose should be to simplify local surface and subsurface data to a scale that aids prediction and further illuminates the broader brush generalisations implicit in continent-wide and global syntheses.

Regional and supra-regional (e.g., continent-wide) geology thus connects global plate tectonics, global climate changes, global eustatic sea-level changes and underpinning studies in geoscience to the more pragmatic applications associated with the search and conservation of natural resources, that is, water, ore deposits and solid earth energy resources. For example, the steadily evolving seismic technology developed by both academia and the oil industry over the past 50 decades provides ever more detailed subsurface images. As a result, for selected areas there are now very detailed 3D seismic images available, but equally important are the available much longer and more widely spaced 2D profiles. Crustal scale seismic profiles, mostly acquired by academic institutions are even longer and typically have less detailed resolution, but have much deeper penetration as they are intended to map the base of the crust and parts of the upper mantle. Each of these and many other geophysical maps and profiles have their proper role. The same can be said for the large spectrum of geochemical/isotope studies. The purpose and scope of regional geology is to judiciously reconcile insights obtained by studies and surveys of the various geoscience disciplines and to end up with a coherent, observation/data-based narrative that explains the geologic evolution of larger regions and is also tied to a narration of evolving, frequently changing global concepts, models and theories. In the process, it will be inevitable that there will be unexpected surprises. These may range from lessons learned from expensive dry holes drilled by petroleum explorers all the way to lofty global hypotheses that fail when tested by incoming new data.

1.2 A historical perspective

There is a widespread perception that the dawn of the geosciences was associated with William Smith, Lyell, Darwin and others. In actuality, geological observations were first and widely used by the earliest civilizations to identify water and mineral resources for bronze, iron, precious metals and coal (see e.g., Agricola, 1556). By the time of William Smith (see Winchester, 2001), the earth sciences were firmly established as observation-based, enabling of the first theories on the evolution of the earth to be drawn directly from observations (see Hutton, 1795; Lyell, 1830–1833). The map developed by William Smith was a direct outcome of the engineering surveys of canals and tunnels. In consequence, by the end of the 1800s, geology had become well established as an applied science, providing services to civil engineering works including roads, tunnels and canals for the military as well as a tool to explore for natural resources.

The parallel exploration of the New Worlds of North and South America and also of Africa by individuals as well as government explorers allowed access to hitherto unknown lands and to new mineral resources. Among exemplary early works are the first map of North America (Guettard, 1752) and the results of the major expeditions by Powell and Hayden in the American West. Ami Boué (Johnson, 1856), followed later by Berghaus (1892), published the first geological map of the world.

About 1700 years ago, exploration and drilling for hydrocarbons probably began with the Chinese who used bamboo casings for their wells. Around the sixteenth century “naphtha” was produced from shallow pits in Baku, Azerbaijan. Drilling for oil in 1813 near Pechelbronn (Alsace, France) marked the inception of petroleum exploration in Europe.

The first modern oil well in North America was drilled by Colonel Drake in Pennsylvania in 1858. Much early oil exploration was focused on areas and surface structures associated with natural oil seepage. It was not until the advent of the internal combustion engine and the change to oil as fuel for cargo and naval ships that there began to be significant demand for oil resulting in systematic onshore oil exploration worldwide initially focused on fold belts and the coastal plains of Texas and Louisiana where there were many natural seeps.

In the late nineteenth and early twentieth centuries, major global syntheses were written first by Suess (1885–1909) followed by Argand (1916, 1922), and later by Stille (1924) and Staub (1928), among many others who contributed significant milestones in regional geology.

They all had the means, intellect and incentive to think big. For example, Suess, in his seminal global geology summary (1885), noted that “the possibility was recognised of deducing from the uniform strike of the folds of a mountain chain, a mean general direction or trend line: such trend lines were seldom seen to be straight but consisted of arcs or curves, often violently bent curves of accommodation; the trend lines of central Europe were observed to possess a certain regular arrangement and to be traceable in part as far as Asia. It was further recognised that the ocean from the mouth of the Ganges to Alaska and to Cape Horn is bordered by folded mountain chains while in the other hemisphere this is not the case so that Pacific and Atlantic types may be recognised.”Suess thus recognised, over a hundred years ago, the fundamental differences between the active (Pacific) and passive (Atlantic) continental margins. He noted the continuity of the circum-Pacific and Alpine–Himalayan fold belts whose association with calc alkaline volcanism and deep earthquakes is now very well known and understood. Suess was also well aware of the problems of major marine transgressions, especially that of the Late Cretaceous. However, Suess thought that the ocean crust was similar to that of the continents and that the oceans owed their origins to “subsidence and collapse.”

The enormous thicknesses of sediments documented in fold belts and their adjacent basins caused major difficulties reconciled in the “geosynclinal” theory of Hall (1882) and Dana (1873). These thicknesses far exceeded the depths of the modern oceans and the sediments typically consisted of shallow marine deposits. Obviously, subsidence had to have taken place to allow the accumulation of such thicknesses. Dana used the term “geosynclinal” with reference to a subsiding and infilling basin resulting from his concept of crustal contraction due to a cooling earth.

The Western Alpine structural zones (see De Graciansky et al., 2011; Trümpy, 2001) soon came to be interpreted in terms of Dana’s geosynclinal model. In this way, Emile Haug (1925) added extra detail by invoking an elongate narrow trough between the continents whose erosion supplied the sediment. Two belts of sedimentary rocks were thought to accumulate in troughs separated by an intervening ridge called a “geanticline.” He designated the Dauphine geosyncline; the volcanic rocks and deep water sediments were termed a “eu-geosyncline” while the trough with mainly shallow water sediments was called a “mio-geosyncline” (see Chapter 4 for a comparison of old and modern definitions). The driving mechanism was thought to be compression between two colliding continents.

A little later, Steinmann (1927) considered that the Alpine ultrabasic and basic igneous rock suites called “ophiolites” (see Chapter 25) were emplaced by injection and differentiation of basic and ultrabasic magmas under marine sediments well before dissection by later thrusts. Today, these ophiolites are known to be fragments of oceanic lithosphere or sub-continental mantle entrained in thrust sheets (see Manatschal and Whitmarsh Chapter 9 and Chapter 25).

The geosynclinal view of the earth seemed comprehensive where mapped in detail but was less than convincing in explaining the relationship between fold belts, volcanoes and seismicity as well as the new data from passive margins in several respects.

Application of the geosynclinal model was valuable in that it provided guidelines for geological exploration and thinking in different fold belts worldwide and particularly those surrounding the Mediterranean. The geosyncline model was classically taught worldwide and remained a mainstay of geology until the 1960s. Notwithstanding the recognition of oceanic and continental crust and the first primitive studies of the deep structure of continental margins in the 1950s, strenuous efforts were made to apply geosynclinal theory to these new and later confirmatory observations. See, for example, Marshall Kay (1951), Drake et al. (1959) and Aubouin (1965).

However, it should be borne in mind that the nineteenth and early twentieth centuries saw the flowering of worldwide geological exploration and the development of many of the sub-disciplines that are embodied in geoscience today. The observations made during this period remain good even though interpretations have changed radically.

At the turn o...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Contributors for Volumes 1A, 1B and 1C
• Foreword and Introduction
• Acknowledgements
• SECTION 1. Rift Systems
• SECTION 2. Active and Cenozoic Rifts
• SECTION 3. Mesozoic and Older Rifts
• SECTION 4. Inverted Rift Systems
• Index