The Leading Hemisphere Terrain (LHT) of Enceladus has experienced distributed deformation expressed by the pervasive development of >100 km wide and >100s km long ductile strike‐slip shear zones and sparsely distributed craters. Within the zones are locally preserved little‐deformed semirigid blocks up to 10–20 km in size with surfaces dominated by impact craters. The edges of these relic blocks display ductile drag folds and smeared tails of rigid fragments, which are indicative of vertical‐axis rotation associated with ductile strike‐slip shear. Kinematic analysis requires the development of the LHT to have been driven mainly by toroidal flow of the ice‐shell material. Additionally, the structural mapping quantifies the shear strain magnitude (2.8) and minimum strain rate (10⁻¹⁷ s⁻¹). If the observed deformation induced by tidal stress, the estimated ice‐shell deformation requires a high heat flux (∼0.13 W/m²) and a thin brittle layer (∼4 km) during the development of the LHT. However, the observed deformation may have formed under high stresses, exceeding 1 MPa and a heat flux similar to the current background observed today.

中文翻译：

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形成遗迹陨石坑块：从前半球的冰壳形变推断出的土卫二上的左旋剪切

土卫二的领先的半球地形（LHT）经历了分布变形，这种变形表现为广泛发展，其宽度大于100 km，长度大于100s km，具有延性的走滑剪切带和稀疏分布的火山口。在这些区域内，是局部保留的几乎未变形的半刚性块体，其大小最大为10–20 km，其表面受撞击坑的支配。这些遗物块的边缘显示出延性的延展褶皱和刚性碎片的拖尾，这表明与延性的走滑剪切有关的垂直轴旋转。运动学分析要求LHT的发展主要是由冰壳材料的环形流动驱动的。此外，结构映射量化了剪切应变幅度（2.8）和最小应变速率（10 ^-17 s ^-1）。如果观测到的由潮汐应力引起的变形，则估计的冰壳变形需要在LHT的发展过程中具有高的热通量（〜0.13 W / m ²）和薄的脆性层（〜4 km）。但是，观察到的变形可能是在超过1 MPa的高应力和类似于目前观察到的当前背景的热通量下形成的。