Name
Multistage Lithospheric Drips Driving Topographic Evolution in Central Anatolia
Description
Global Navigation Satellite System (GNSS) and INSAR measurements indicate that the Konya Basin in Central Anatolia is undergoing rapid subsidence (>5 cm/yr) within the uplifting orogenic Central Anatolian plateau. This is also a region where seismic tomography data reveal removed lithospheric mantle beneath the plateau. It has been interpreted that the plateau tectonics are the consequence of Miocene era folding of the Kirşehir Arc and formation of an arc root, which subsequently dripped and removed mantle lithosphere beneath the plateau. Further geophysical data reveal a high velocity seismic anomaly beneath the basin, a negative residual topography and localized thickened crust, which are interpreted as evidence for a lithospheric drip. However, this interpretation does not explain the current subsidence and formation of the Konya Basin. Here we use scaled 3D analogue/laboratory experiments with quantitative analyses through high-resolution Particle Image Velocimetry (PIV) to explore the drip tectonic processes. Experimental results reveal that lithospheric dripping may occur in multiple stages where a large-scale primary event may be followed by a small-scale secondary event. The models show that a secondary drip can cause local subsidence within an overall uplifting plateau. This is consistent with the tectonics in Central Anatolia where a large-scale primary drip led to the uplift of the Central Anatolian Plateau over the past ~10 My, while a second stage of dripping has initiated beneath the Konya Basin driving localized subsidence within the basin while maintaining muted levels of horizontal strain.