GNGTS 2024 - Atti del 42° Convegno Nazionale

Session 1.3 GNGTS 2024 First, we use the MIDAS algorithm (Blewit, 2016) to process 21 GNSS tme series spanning 1997– 2022, provided by the Nevada Geodetc Laboratory, and we produce a robust tectonic velocity soluton. Then, we calculate a new geodetc strain rate model using the VISR code (Shen et al., 1996; Shen et al., 2015), with an optmal mesh grid defniton of 0.5x0.5 degrees, that best fts our study area. Second, we combine our new geodetc strain rate model with the Moho depth and rheological parameters (Tab. 1), such as Geothermal Heat Flow (GHF), heat producton and thermal conductvity previously published in the literature to determine the YSE beneath Graham Land. We performed several numerical experiments in which the GHF and the rheological parameters were varied to compute predictons of the YSE. We explored the range of uncertainty in each parameter by a trial-and-error procedure with discrete sampling steps. Each combinaton of GHF and temperature coefcient for creep rheology consttutes an independent simulaton. For each combinaton, the model predictons were computed with a MATLAB code; a fowchart illustratng our modeled workfow is shown in Fig. 2. The results of our study demonstrate that the “jelly sandwich” and the “crème brûlée” models are both valid for the Graham Land lithosphere, depending on specifc thermal and rheological conditons considered.