Publication Date:
2023-11-13
Description:
Rifting and continental break‐up are fundamental tectonic processes, the understanding of which is of prime importance. However, the vast temporal and spatial scales involved pose major limitations to researchers. Analog tectonic modeling represents a great means to mitigate these limitations, but studying the complex internal deformation of lithospheric‐scale models remains a challenge. We therefore present a novel method for lithospheric‐scale rifting models that are uniquely monitored in an X‐ray CT scanner, which combined with digital image correlation (DIC) techniques, provides unparalleled insights into model deformation. Our first models illustrate how the degree of coupling between competent lithospheric layers, which are separated by a weak lower crustal layer, strongly impacts rift system development. Low coupling isolates the upper crust from the upper lithospheric mantle layer below, preventing an efficient transfer of deformation between both layers. By contrast, fast rifting increases coupling, so that deformation in the mantle is efficiently transferred to the upper crust, inducing either a symmetric or asymmetric (double) rift system. Furthermore, oblique divergence may lead to en echelon graben arrangements and delayed exhumation of the lower crustal layer. The successful application of our novel modeling approach, yielding these first‐order insights, provides a clear incentive to continue running lithospheric‐scale rifting models, and to apply advanced monitoring techniques to extract as much information from models as possible. There is indeed a broad range of opportunities for follow‐up studies within (and beyond) the field of rift tectonics.
Description:
Plain Language Summary:
The Earth's surface consists of tectonic plates that are in constant motion, driven by titanic forces deep within the planet. One of the key plate tectonic processes is the stretching (rifting) and eventual break‐up of continents, leading to the opening of oceanic basins. Understanding the mechanisms involved is of great importance. However, studying continental break‐up is challenging due to the vast size of plate tectonic systems, and the extensive timescales over which they evolve: plate tectonic processes can rarely be directly observed. A practical solution to this issue is the use of analog experiments, which reproduce these processes in a matter of hours or days in a modestly sized laboratory. However, a major obstacle that remains is the opacity of these models: similar to tectonic plates, these models are opaque, so that their internal evolution remains hidden. X‐ray CT‐scanning provides an unrivaled means to reveal a model's internal structures during a model run. Here we present the first‐ever application of CT‐scanning to monitor relatively complex lithospheric‐scale models of continental rifting. The CT scans provide unique insights into the internal evolution of such models, and we point out various possibilities for interesting follow‐up studies.
Description:
Key Points:
We present the first‐ever lithospheric‐scale analog models of rifting monitored in a CT scanner, revealing their complex internal deformation.
We quantify this deformation via Digital Image Correlation analysis, and show the impact of coupling and oblique rifting on rift evolution.
The successful application of our novel modeling approach provides a strong incentive for follow‐up tectonic modeling studies.
Description:
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
http://dx.doi.org/10.13039/501100001711
Description:
Helmholtz‐Zentrum Potsdam ‐ Deutsches GeoForschungsZentrum GFZ
http://dx.doi.org/10.13039/501100010956
Description:
https://doi.org/10.5880/fidgeo.2022.030
Description:
https://doi.org/10.5880/fidgeo.2022.008
Description:
https://doi.org/10.5880/fidgeo.2023.006
Description:
https://doi.org/10.5880/fidgeo.2023.005
Keywords:
ddc:550.78
;
rifting
;
analog modeling
;
continental break‐up
;
X‐ray CT‐scanning
;
visualization
;
monitoring
Language:
English
Type:
doc-type:article
Permalink
