Processes in
Structural Geology
and Tectonics

 

Ben van der Pluijm

Stephen Marshak

 

ISBN: 978-1-5323-0282-4; v2
©2016/2017

 

Preface

 

ORGANIZATION

Blocks and Units

CONNECTION WITH "EARTH STRUCTURE" TEXTBOOK

INFORMATION FOR USERS

Layout and Use

Annotation

Search, Customized and Internet

Site Access
FAQ

ABOUT THE AUTHORS

CODA

 

BACK TO PSG&T HOME

 

 

ORGANIZATION

Processes in Structural Geology and Tectonics combines fundamentals, observations and applications into a process-oriented approach to structural geology.  The treatment differs significantly from prior offerings in this area, by focusing on integration of content.   The material starts with examination of the behavior and properties of the upper crust, which is dominated by brittle structures, followed by considering a lower crust that deforms primarily by crystal-plastic processes.  As such, the text is thematically organized by deformation regime, shown below as a function of depth with characteristic fault rocks, temperature, lithostatic and failure/flow stress conditions. Whole-Earth structure and the tectonic settings of deformation structures today (shown below) and in the past are examined in the third block of the e-text.

 

Synoptic diagram of a displacement zone showing the frictional and plastic regimes, the frictional–plastic transition, metamorphic facies (reflecting temperature, T), lithostatic pressure (Pl), rock strength (represented by differential stress, σd) and characteristic fault rocks.

 

The first chapter block emphasizes the stress-dependency of fracturing and friction, so force and stress and elastic properties of material are discussed.  After fracture and friction criteria are established, (brittle) deformation structures and their processes are examined in more detail.  This organization allows multiple paths to further exploration, such as the use of more sophisticated mathematical approaches (like matrix algebra) beyond vectors and trigonometry used here.

 

The second chapter block examines processes in the crust’s deformation regime where temperature dominates rock behavior and large, time-dependent strain can accumulate.  Strain and strain rate are introduced here, and the rheologic property of viscosity is used to quantify the flow processes in this regime.  Deformation in the plastic regime produces new rock elements, such as foliations and pervasively-sheared crust, which are included in the examination of related structures.  As before, the organization readily allows deeper investigation into various topics, as well as more advanced mathematical treatment.

 

The major and minor plates of today’s Earth. Major plates are: Pacific, Nazca, North American, South American, Eurasian, African, Indo-Australian and Antarctic plates; minor plates include: Juan de Fuca, Caribbean, Cocos, Scotia, Arabian, Philippine plates. Ocean ridges and transfer faults (heavy lines) and trenches (lines with teeth on the overriding plate) mark today's active plate boundaries. (click on image for larger version)

 

The third block places deformation structures in a plate tectonics context and introduces realistic rheologic behaviors for the lithosphere that combine elasticity and viscosity, such as elastico-viscous behavior.  Also, non-linear rheologies are introduced, toward developing a comprehensive crust-mantle rheologic framework for plate tectonics.  The treatment offers ample opportunity for more advanced examinations, such as geodynamic modeling approaches and integration with other fields in geology (mineralogy, petrology, geophysics and geochemistry).  In three units, the occurrence and meaning of regional deformation structures that were introduced in earlier sections are discussed in the context of extensional, contractional and wrench tectonics.

 

Blocks and Units

  1. Geologic Structures and Deformation Regimes

    Block I - Frictional Regime

  1. Force and Stress
  2. The Frictional Regime and Elasticity
  3. Joints and Veins
  4. Faults and Faulting

Block II - Plastic Regime

  1. Deformation and Strain
  2. The Plastic Regime and Viscosity
  3. Folds and Folding
  4. Deformation Fabrics and Fabric Elements

Block III - Plates and Tectonic Settings

  1. Rheology and the Lithosphere
  2. Whole Earth Structure and Plate Tectonics
  3. Extensional Tectonics - Rifting and Divergence
  4. Contractional Tectonics - Convergence and Collision
  5. Wrench Tectonics - Strike-slip Boundaries
  1. A Global View and Regional Essays
Additional Materials

CONNECTION WITH "EARTH STRUCTURE" TEXTBOOK

Prior users of Earth Structure: An Introduction to Structural geology and Tectonics will find that content of PSG&T relies on editions of this print text, notably the 2nd edition.  However, we significantly changed the organization and treatment of fundamentals, consolidated topics that were previously scattered throughout, removed material and shortened text.  Some content was placed in Supplementary Materials and essays on regional geology are included as unchanged PDFs only.  Text from print editions was edited (and trimmed) to allow this new approach, in addition to updated and new figures (including modest colorization, while maintaining the simplicity of supporting art).  Relevant figures from Earth Structure 2nd edition are identified in the figure captions of PSG&T as [x.x].  The engaging writing style of earlier print editions has been retained as well as the inherent modularity of material that allows alternative organizations.

INFORMATION FOR USERS

Chapters are updated on an annual basis, as needed, while minor editing (such as typos) is done regularly.  Each Unit consists of a Chapter and Supplementary Materials, with the latter containing complemenatary information that may be useful (such as descriptions of terms, readings) and further explorations in the area.

Translate

A (crude) language translation function using Google Translate is included in each chapter, using a drop-down box. The translation engine may struggle with professional terminology, but offers a useful, basic narrative in the selected language.

 

Each Unit includes a supporting PowerPoint presentation that presents the material as used by the lead author (BvdP).  These files are publicly available as PDFs, but instructors who adopt the text may also request PowerPoint originals.  Additionally, each Unit is accompanied by a lecture recording with voice and coupled PowerPoint (BvdP).  These recorded lectures are seperately available to instructors upon request (email procsgt@gmail.com).

 

Layout and Use

Notes The material works for standard screens, but also as a narrow window on desktops and smaller portable devices in landscape mode, supporting the parallel use of text and external annotation programs (such as Word, Evernote).  Alternatively, a website markup environment, called Hypothes.is (free, open-platform), can be used for annotation; see description below.  Figures are embedded, but also available as stand-alone jpgs for greater detail and for use in presentations (with acknowledgment to psgt.earth.lsa.umich.edu).  The text is designed to scale to smaller tablet and smartphone screens, including portrait mode, with similar enlarged figure capability through a native <view image> command.

 

Annotation

A Hypothes.is PSG&T usergroup (unique ID: 59nnowM5) has been created for shared, unmoderated annotation of pages. Join this usergroup by clicking on https://hypothes.is/groups/59nnowM5/psgtusers. Users agree to submit educational and informational (and respectful) notes that are suitable for public posting, as the group is unmoderated (for now). 

 

Search, Customized and Internet

Instead of an generic, internet-powered index, the PSG&T site offers a powerful, customized Zoom Search function that identifies and highlights the location and extended context of search term(s) in relevant pages.  The PSG&T search engine is locally powered and managed, and does not use Google, Bing, Yahoo or a similar internet search engine. Your search history is not tracked, but search words are tabulated.
In addition to Zoom's customized site search, highlighting of any term allows for browser-embedded internet search on PC or mobile device, shown on the left, respectively. This functionality depends on one's browser and OS, and user's default search engine.

 

Site Access

Full text access requires a UserID and Password.  Access is given for a restricted period, with details and a progressive, nation-income based fee structure that are described on the website's homepage (Charges).  Instructors can request free examination access to the full text and receive long-term access upon adoption.  PDF versions of lecture PowerPoint files are publicly available, identified as Lecture Presentation in each Unit.  Additional information and solutions can be found on the Frequently Asked Questions page (FAQ).
Contact procsgt@gmail.com for textbook adoption and other access info.

 

FAQ

A range of commonly asked questions are answered on the Frequently Asked Questions page.

ABOUT THE AUTHORS

Ben van der pluijmBen van der Pluijm is Bruce R. Clark Collegiate Professor of Geology and Professor of the Environment at the University of Michigan-Ann Arbor, and Editor-in-Chief of the interdisciplinary science journal Earth's Future. He is (co-)author of numerous research articles and is editor/board member of several international journals and organizations. His group's geology research focuses on crustal fault rocks and processes, architecture of collisional belts, intraplate deformation, microstructures and textures, and applications of geochronology and geochemistry to structural geology, with field areas around the world.  His second interest area is Societal Resilience, dealing with planet-human interaction. Educational and public outreach activities include learning technologies and lectures on geology and global change.
Website: http://globalchange.umich.edu/ben/

 

Stephen MarshakStephen Marshak is Professor of Geology and Director of the School of Earth Society and Environment at the University of Illinois, Urbana-Champaign. He holds a Ph.D. from Columbia University, an M.S. from the University of Arizona, and a B.A. from Cornell University. He has served as Chair of the Division of Structural Geology and Tectonics of the Geological Society of America. He has written numerous research articles on topics in structural geology and tectonics, and has authored and co-authored three other successful books: Basic Methods of Structural Geology; Earth: Portrait of a Planet; and Essentials of Geology.
Website: https://goo.gl/yeE5vy.

CODA

We hope that you enjoy this online, process-based approach to Structural Geology and Tectonics, and that is serves the needs of today’s teachers and learners.  We are always interested in your feedback and any suggestions that will improve the material and presentation (procsgt@gmail.com).

 

Ben van der Pluijm and Stephen Marshak

2016/2017


Back to Preface Contents


Back to PSG&T Home

v1.4; Last update: 14-jun-17