Welcome 1 This is a document to explains the chosen concept to the animator. This will take you through a 5 section process to provide the necessary details to the animator before starting the animation. The legend on the left will indicate the current status of the document. The big Black coloured number will denote the current section, the Grey color would denote the completed sections, and the Turquoise color would denote the remaining sections. The slides having yellow background (like this one) are the 'Instruction slides' 2 3 4 5

Piggyback Thrust A piggyback thrust sequence refers to imbrications where new thrust segments develop closer to the foreland than the existing thrusts. Thus, the early formed faults and the associated folds are carried piggy-back in the hanging-wall to later-formed thrusts. Related LOs: > Prior Viewing: Structural geology > Future Viewing : Course Name: Plate Tectonics Level: Post graduation Author: Arpita Roy Mentor: Prof. Soumyajit Mukherjee Title of the concept *The contents in this ppt are licensed under Creative Commons Attribution-NonCommercial-ShareAlike 2.5 India license

Learning objectives 1 After interacting with this Learning Object, the learner will be able to: Describe the formation of piggyback thrust sequence 2 3 4 5

1 Master layout or diagram 2 3 4 5 Make a schematic diagram of the concept Explain the animator about the beginning and ending of the process. Draw image big enough for explaining. In the image, identify and label different components of the process/phenomenon. (These are like characters in a film)‏ Illustrate the basic flow of action by using arrows. Use BOLD lines in the diagram (minimum 2pts.)‏ In the slide after that, provide the definitions of ALL the labels used in the diagram You may have multiple master layouts. In this case, number the master layout. (e.g. Master layout 1, 2, 3…)‏ 2 3 4 5

1 Master layout 2 3 4 5 Animator should redraw diagrams Text written in blue colour are instruction for animator, these would not appear in the final animation Text labeled in black colour would popup in animation Green arrows indicate the flow of the phenomenon/process 2 3 4 5

Keywords/ Definitions 1 Fault: Fault is a structural feature in the Earth surface in which one side/ block moves relative to the other side/block Hanging wall and Foot wall: “The block above the fault is called the hanging wall; the block below the fault is the footwall” (Billings, 1972) Thrust: Thrust faults are low angle reverse faults where the block above the fault plane (hanging wall block) moves up relative to the block below the fault plane (foot wall block) Imbricate : Thrust faults that have en echelon arrangement in cross-sections Ramp : Inclined fault plane in thrust fault system Oblique slip fault: It is combination of strike slip and dip slip motion Back-thrust fault: The consisting ramps associated with reverse faults with opposite sense of displacement compared to the normal fault form back-thrust fault Contractional fault: Contractional fault shortens any area under consideration and results lithologic layering Duplex structure: Duplex structure is similar to the cards in a tilted card deck Graben: Graben is a depressed block bounded by faults by both sides 2 3 4 5

1 Master layout: 1 2 3 4 5 1A 1B 1C Thrust 1 Simple ramp Branching thrust fault Simple ramp Piggyback thrust sheet 1A 1B 1C Thrust 2 3 4 Piggy back thrust sequence : The late thrust develops in the footwall of the original thrust. Structurally higher and older thrusts and hanging-walls are carried forward in a piggyback manner by lower, younger thrusts. 5

1 Explain the process In this step, use an example to explain the concept. It can be an analogy, a scenario, or an action which explains this concept/process/topic Try to use examples from day-to-day life to make it more clear You have to describe what steps the animator should take to make your concept come alive as a series of moving images. Keep the examples simple to understand, and also to illustrate/animate. 2 3 4 5

Analogy 1 When soft clay is pushed over a hard object, a part of the clay may start moving in a direction opposite to the bulk clay’s movement direction. 2 3 4 5

3 Stepwise description of process 1 2 4 5 The goal of the document is to provide instructions to an animator who is not a expert. You have to describe what steps the animator should take to make your concept come alive as a moving visualization. Use one slide per step. This will ensure clarity of the explanation. Add a image of the step in the box, and the details in the table below the box. You can use any images for reference, but mention about it's copyright status The animator will have to re-draw / re-create the drawings Add more slides as per the requirement of the animation 2 3 4 5

Step: 1 Simple ramp formation Description of the action Audio narration Text to be displayed 1) First show the parallel layers (as shown by blue & orange colors) 2) Show small thrust or overlapping of the part 1 (has been circled over here) 3) Time duration will be 5 seconds. It is also known as low angle floor thrust.

Step: 2 Branching ramp formation Piggyback thrust sheet 1B Branching thrust fault Description of the action Audio narration Text to be displayed Show two overlapping situations as shown here (two overlapped part has shown by numbering with inscribed circle) Time duration will be 5 seconds There is the combination of the two thrusts connected through a steeper ramp known as flat-ramp-flat.

Step: 3 Final stage of piggyback thrust sheet formation Description of the action Audio narration Text to be displayed Overlapping part will be increased. In this case it will be three in number)as shown in the diagram) The time gap between Fig. 1A, Fig. 1B, Fig. 1C should be around 5 seconds The whole phenomenon depicts duplex development and also known as thrusting propagation (as it propagates and form Piggyback thrust sheet). The later thrust develops in the footwall of the original thrust, structurally higher and older thrusts and hanging-walls are carried forward in a piggyback manner by lower, younger thrusts.

1 Animation design Please see the design template provided in the next slide. This is a sample template, and you are free to change as per your design requirements. Try and rename the tabs / buttons / sections / subsections as shown in the template. Use ‘callouts’ as shown above to explain the source of content. Ex: If the call out is placed at the Tab 01, and you want the content to be taken from slide 3 of this presentation, then place this callout on the Tab 01, and write ‘Slide 3’ inside the callout. 2 3 Slide 3 4 5

Interactivity area 1 2 3 Branching thrust fault Simple ramp Piggyback thrust sheet A B C Thrust Interactivity area Start Definitions Model 1 Summary Replay Credits

Self- Assessment Questionnaire for Learners APPENDIX 1 Self- Assessment Questionnaire for Learners Please provide a set of questions that a user can answer based on the LO. They can be of the following types: These questions should be 5 in number and can be of objective type (like MCQ, Match the columns, Yes or No, Sequencing, Odd One Out). The questions can also be open-ended. The user would be asked to think about the question. The author is requested to provide hints if possible, but a full answer is not necessary. One can include questions, for which the user will need to interact with the LO (with certain parameters) in order to answer it. It is better to avoid questions based purely on recall.

Questionnaire: APPENDIX 1 1) In the Fig. show the simple ramp, the flat and the branching fault. (Refer Master layout) 1 2 3 Branching thrust fault Simple ramp Piggyback thrust sheet A B C Thrust flat

Questionnaire: 2) Piggyback thrust is compared with which faults? a) It is mainly compared with strike slip fault b) Compared with oblique slip fault, back thrust fault etc c) None of these d) Compared with vertical fault 3) How the duplex develops in piggyback thrust? a) Towards the left side of the structure known as propagation b) Towards right to left of the structure known as propagation c) It can develops from both sides, left to right and vice versa d) None of these are correct answer

Questionnaire: 4) In an orogenic zone piggy back thrust is related with which structural feature and why? a) Rift basin (graben), as the angle is very low while forming the structure b) Contractional faults, piggy back thrust connected with each other by low angle reverse fault. c) Duplex structure, as the piggyback thrust resembles like the cards tilted in deck d) All of these are correct e) Only b and c are correct f) a is the appropriate answer

Links for further reading APPENDIX 2 Links for further reading In the next slide, provide some reference reading material for the users. It could be books, reference publications, or website URLs.

Links for further reading APPENDIX 2 Links for further reading Fossen H., 2010. Structural geology. Cambridge University Press, Cambridge. pp. 313-320.

Links for further reading Twiss, R.J., Moores E. M., 2007. Structural Geology. W. H. Freeman and Company, New York. pp.

APPENDIX 3 Summary Please provide points to remember to understand the concept/ key terms of the animation, in the next slide. The summary will help the user in the quick review of the concept.

APPENDIX 3 Summary Piggy-back thrust : A thrust sequence formed by the progressive development of thrusts by collapse of the footwall. The newly formed thrust becomes the active thrust surface and older thrusts, with their thrust slices, are carried forward on it passively.