Shape of plutons in crustal shear zones: A tectono-magmatic guide based on analogue models

Plutons in crustal shear zones may exploit inherited structures, interfere with strain localizing or be deformed passively. To constrain the relative timing of such tectono-magmatic relationships natural settings is not always straight-forward. We here present sandbox-type analogue model experiments simulating magma emplacement into simple and transtensional to test diagnostic potential pluton shape respect setting. Observations based on surface deformation intrusion exemplify interplay between evolving tectonic structures uprising. observe markedly asymmetric intrusions association dikes reflecting regional stresses, fault pattern finite field. At same time, presence an modifies evolution, but only transiently, resulting short-lived faults, reactivation inversion. Diagnostic attributes include pluton's aspect ratio, its orientation amplitude as well dike association. Accordingly, syn-tectonic show highest amplitudes, intermediate elongation compared other scenarios. They are oriented parallel Riedel shears shear, respectively compression direction transtension. Post-tectonic least elongated, have medium amplitudes shears. Pre-tectonic characterized by lowest ratios direction. Intrusions generally less elongate than those zones. Experimental results tested against observations from examples validating for setting emplacement.