Akademik Veri Yönetim Sistemi
AGU Fall Meeting , California, Amerika Birleşik Devletleri, 11 - 15 Aralık 2023, ss.1
Geological and geophysical observations reveal instances of surface subsidence, uplift, shortening, and removed mantle lithosphere; interpreted as manifestations of mantle lithospheric drips. This process removes or thins the lithosphere in intraplate settings such as active orogenic regions driving basin formation and topographic evolution (e.g., Central Andes and Central Anatolia). A series of scaled 3D analogue/laboratory experiments were conducted with quantitative analyses using the high-resolution Particle Image Velocimetry (PIV). Experimental outcomes reveal that a lithospheric drip may be either ‘symptomatic’ or ‘asymptomatic’ depending on the surface manifestations of the drip in the upper crust and determined by how well coupled a drip was to the upper mantle lithosphere. A symptomatic drip will produce subsidence followed by thickening/shortening, creating distinct ‘wrinkle-like’ structures in the upper crust whereas an asymptomatic drip yields subsidence or uplift, with no evidence of shortening in the upper crust. The method of drip initiation influenced how well coupled the drip was to the upper mantle lithosphere to promote shortening of the upper crust. Seismic tomography and paleoelevation data reveal a symptomatic drip beneath the Arizaro Basin (Central Andes). Seismic tomography, surface strain and Global Navigation Satellite System (GNSS) data indicate an asymptomatic drip beneath the Konya Basin (Central Anatolia). Analogue models allow us to view the 3D topographic evolution and deformation of the crust in detail, but deeper processes occurring inside the mantle lithosphere are not as accessible. ASPECT mantle convection code was used to create numerical models of the lithospheric dripping process with added thermal properties. These numerical models provide further insights into the dynamics between the mantle lithosphere and crust and how this may determine whether a drip is ‘symptomatic’ or ‘asymptomatic’. This improves our understanding of how different types of lithospheric drips influence the topographic evolution of sedimentary basins in orogenic regions. These models improve our understanding of tectonic processes occurring independently of plate movements, which aids our understanding of orogenic uplift on planets lacking plate tectonics such as Venus.