The last Scottish Ice Sheet (SIS) expanded from a pre-existing ice cap after ∼35 ka. Highland ice dominated, with subsequent build-up of a Southern Uplands ice mass. The Outer Hebrides, Skye, Mull, the Cairngorms and Shetland supported persistent independent ice centres. Expansion was accompanied by ice-divide migration and switching flow directions. Ice nourished in Scotland reached the Atlantic Shelf break in some sectors but only mid-shelf in others, was confluent with the Fennoscandian Ice Sheet (FIS) in the North Sea Basin, extended into northern England, and fed the Irish Sea Ice Stream and a lobe that reached East Anglia. The timing of maximum extent was diachronous, from ∼30–27 ka on the Atlantic Shelf to ∼22–21 ka in Yorkshire. The SIS buried all mountains, but experienced periods of thickening alternating with drawdown driven by ice streams such as the Minch, the Hebrides and the Moray Firth Ice Streams. Submarine moraine banks indicate oscillating retreat and progressive decoupling of Highland ice from Orkney–Shetland ice. The pattern and timing of separation of the SIS and FIS in the North Sea Basin remain uncertain. Available evidence suggests that by ∼17 ka, much of the Sea of the Hebrides, the Outer Hebrides, Caithness and the coasts of E Scotland were deglaciated. By ∼16 ka, the Solway lowlands, Orkney and Shetland were deglaciated, the SIS and Irish Ice Sheet had separated, the ice margin lay along the western seaboard, nunataks had emerged in Wester Ross, the ice margin lay N of the Cairngorms and the sea had invaded the Tay and Forth estuaries. By ∼15 ka, most of the Southern Uplands, the Firth of Clyde, the Midland Valley and the upper Spey valley were deglaciated, and in NW Scotland ice was retreating from fjords and valleys. By the onset of rapid warming at ∼14.7 ka, much of the remnant SIS was confined within the limits of Younger Dryas glaciation. The SIS, therefore, lost most of its mass during the Dimlington Stade. It is uncertain whether fragments of the SIS persisted on high ground throughout the Lateglacial Interstade.

中文翻译：

---

最后的苏格兰冰盖

最后一个苏格兰冰盖（SIS）在约 35 ka 后从一个预先存在的冰盖膨胀。高地冰占主导地位，随后形成了南部高地冰块。外赫布里底群岛、斯凯岛、马尔、凯恩戈姆和设得兰群岛支持持久独立的冰中心。扩张伴随着冰分迁移和流动方向的转换。苏格兰滋养的冰在某些区域到达大西洋大陆架断裂处，但在其他区域仅到达中部大陆架，与北海盆地的芬诺斯坎第冰盖 (FIS) 汇合，延伸到英格兰北部，并注入爱尔兰海冰流和到达东英吉利的裂片。最大范围的时间是历时性的，从大西洋大陆架的~30-27 ka到约克郡的~22-21 ka。SIS掩埋了所有的山脉，但在 Minch、赫布里底群岛和 Moray Firth 冰流等冰流的驱动下，经历了增厚和下降交替的时期。海底冰碛岸表明高地冰与奥克尼-设得兰冰的振荡退缩和逐渐脱钩。北海盆地 SIS 和 FIS 分离的模式和时间仍然不确定。现有证据表明，到 17 ka 时，赫布里底海、外赫布里底群岛、凯斯内斯和苏格兰东部海岸的大部分地区已经消融。到 16 ka 时，索尔韦低地、奥克尼和设得兰群岛消融，SIS 和爱尔兰冰盖已经分离，冰缘位于西海岸，努纳塔克出现在西罗斯，冰缘位于凯恩戈姆和海已经侵入了泰河口和福斯河口。到 15 ka，南部高地的大部分地区，克莱德湾、米德兰河谷和斯佩河上游的冰川消退，苏格兰西北部的冰层正在从峡湾和山谷中退去。到 14.7 ka 的快速变暖开始时，大部分残留的 SIS 被限制在 Younger Dryas 冰川作用的范围内。因此，SIS 在 Dimlington 体育场失去了大部分质量。目前尚不确定 SIS 的碎片是否在整个晚冰期 Interstade 的高地上持续存在。