| Navigability:
It is not very good mainly due to the absence of a clear plan.
Organization:
The organization is a major flaw of this report. There is no clear and detailed table of content. Consequently the reader is left with a stack of slides vaguely organized in sections showing little links between one another.
I find some of the sections difficult to read due to a poor use of ponctuation and a poor writing style such as:
Depending upon the stress and strain direction, the plate strength and respective geotherm different features and structures will result.
Instead one good have written: Contrasted structural characteristics may develop depending on a number of parameter including: orientation and magnitude of stress, the strengh of the stretched lithosphere and the geotherm.
Another example.
In the case of hotspots, the activeness of various crustal plates is the major movement, not the convecting plumes. I have no idea what you try to say.
Figures:
Excepted from Slide 15 onward, there is no coherent referencing of the figure. Each of them should have a number (Figure 2. etc) with a proper caption.
References: None are included in the report as they all should.
Comments on the content.
Introduction:
A proper introduction should answer the following question:
Why is that topic important,?
Why should someone be interested in that topic?
Why should someone read this report?
A proper introduction should also inform the reader about the topics that are covered and the topics which are not. A brief description of the organization of the report should also be given to help the reader to understand the logic of the report and how the different section links together.
Slide 1 to 4: What is the purpose of this section? What should the reader learn from it? Some of the concepts presented are not or very ill defined, sometimes they are mixed together such as in slide 2 where Active rifting, wide rift, McKenzie model, Wernicke model, diffuse rift are all illustrated with one single figure.
Slide 5:
Initiation of extensions is due to various factors, they are:
a) Mantle plumes/Hotspots
c) Subsidence/Trench rollback where is the b)? What about Slap pull as a driving force for extension? What about gravitational force in thickened crust? What about pull-apart basin formed along strike-slip faults.
Mantle plumes and hotspots are of similar principles. Poor writing style. Hot spot is the surface expression of mantle plumes. Mantle plumes do not pushes anything as they tend to spread under the lithosphere.
Slide 6: Subsidence/Trench rollback
This process is due to the cooling of lithosphere over time. Please explain, as the slab is subducted it becomes hotter not colder. What triggers the increase of the slab dip is not cooling. This slide does not provide sufficient explanation to understand what is extension related to slab roll back.
Slide 7: Strength: What is the purpose of that slide? What do you feel writing about Strength was important at that stage of the report? Please explain the logic you want the reader to follow.
On the figure it is said that the lithosphere is cool (right), rigid (right), brittle (wrong).
The rheologies of the upper crust, lower crust and mantle are assumed to be controlled by dislocation creep in quartz, plagioclase and olivine respectively. How about brittle deformation?
Slide 8: Geotherm: What is the purpose of the figure?
Slide 9: Crustal thickness: Are we dealing with the thickness of the crust or that of the lithosphere? The picture is nice but totally irrelevant. At third year level we know what the crust is.
….a thicker crust would retain more heat than a thinner crust. Do you mean: …would produce more heat…
Slide 10: Rate of Deformation
The rate at which a lithospheric crust undergoes an extension can counteract the physical dimension of a lithosphere. ????
Slide 11 and 12 : Shearing model. What should the reader learn from this which is relevant to Extensional Tectoncis? Can your try to put your message into a proper context?
a strong lower lithosphere will produce different extensional features than a weak lower lithosphere. Please explain.
Slide 13: Strain condition:
There are three modes of continental extension, the core complex mode, the wide rift mode and the narrow rift mode. How this articulates with other classification scheme (active versus passive rifting, McKenzie versus Wernicke models)? There is no links between the various section which make this report unreadable.
Slide 14: What’s the point of this figure? How does it related to slide 13? How does it links with Slide 13?
Slide 15: Plate 1 doesn’t show what the plate’s caption pretends it does.
A development of major sedimentary basins beneath the continental shelf … A basin beneath the continental shelf? Do you mean... on the continental shelf?
Slide 16:… Cenozoic extensional deforamtion in… deformation. Thanks.
This slide needs more explanation. What is the message here?
Passive margins are most widespread manifestation of Mesozoic and Cenozoic extensional deforamtion in continental lithosphere. Please explain why.
Slide 17: there is some overlap with slide 13. Somehow this slide 13 and 17 should be linked together.
Slide 18: This plate, as most of the figure show on this report show be properly referenced. Where is plate 6 coming from?
Overall this report is pretty disappointing. There no plan, no logic, no direction. A stack of ill defined slides does not constitute a report. Is the reader in position to learn something from this report? I let you answer that question.
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