The study area is located across the Kalahari Craton – Maud Belt boundary in Dronning Maud Land (DML), Antarctica. The ∼1100 Ma Maud Belt in the east is situated where the ∼900–600 Ma East African and ∼530–500 Ma Kuunga orogenies overlap. The Kalahari Craton cover in the west of the study area comprises ∼1100 Ma Straumsnutane Formation lavas in Straumsnutane. In Straumsnutane, early ∼1100 Ma low-grade structures suggest top-to-the-NW deformation. Younger ∼525 Ma structures suggest conjugate top-to-ESE and -WNW transport under low-grade conditions. Western Straumsnutane and Ahlmannryggen do not show the same complex deformation, the intense deformation being restricted to NE Straumsnutane along the eastern margin of the Kalahari Craton. In Sverdrupfjella, in the east, the Maud Belt is underlain by medium-grade, deformed ∼1140 Ma supracrustal gneisses and younger intrusions. Four deformation phases in the gneisses comprise D1 + D2 with top-to-the-N and -NW folds, D3 top-to-the-S and -SE folding and D4 brittle faulting. Syn-D3 emplacement of granitoid veins is inferred at ∼490 Ma. Comparison of the deformation vergence of NE Straumsnutane with western Sverdrupfjella suggests D1 in Straumsnutane is correlatable with D1 + D2 Mesoproterozoic structures in western Sverdrupfjella. D2 deformation in Straumsnutane can be correlated with D3 structures and Cambrian-age granites in Sverdrupfjella. D2 deformation in eastern Straumsnutane and D3 in western Sverdrupfjella are inferred to have occurred in a mega-nappe footwall, implying the Ritscherflya Supergroup cratonic cover in eastern Straumsnutane was partially submerged in the footwall, the mega-nappe formed during Gondwana amalgamation, involving collision between N and S Gondwana in the Kuunga Orogeny, ∼530–500 Ma ago.

中文翻译：

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南极洲 Dronning Maud Land 西部 Straumsnutane 和西部 Sverdrupfjella 地区的结构演化：对冈瓦纳合并的影响

研究区位于南极洲 Dronning Maud Land (DML) 的卡拉哈里克拉通 - 莫德带边界。东部～1100 Ma Maud 带位于～900-600 Ma 东非和～530-500 Ma Kuunga 造山带重叠的地方。研究区西部的喀拉哈里克拉通盖层包括~1100 Ma Straumsnutane 组熔岩。在 Straumsnutane，早 1100 Ma 低等级结构表明顶部到 NW 变形。较年轻的~525 Ma 结构表明在低等级条件下共轭顶部到 ESE 和 -WNW 传输。西部 Straumsnutane 和 Ahlmannryggen 没有表现出相同的复杂变形，强烈的变形仅限于沿卡拉哈里克拉通东部边缘的 NE Straumsnutane。在东部的 Sverdrupfjella，Maud 带下面是中品位，变形~1140 Ma 地壳上片麻岩和较年轻的侵入体。片麻岩中的四个变形阶段包括 D1+ D2具有顶到 N 和 -NW 折叠，D3top-to-the-S 和 -SE 折叠和 D4脆断层。同步D3花岗岩脉的侵位推断在~490 Ma。NE Straumsnutane 与西部 Sverdrupfjella 变形辐散度的比较表明 D1在 Straumsnutane 与 D 相关1+ D2Sverdrupfjella 西部的中元古代构造。D2Straumsnutane 中的变形可以与 D 相关3Sverdrupfjella 的结构和寒武纪花岗岩。D2东部 Straumsnutane 和 D 的变形3Sverdrupfjella 西部的大推覆层被推断发生在一个巨型推覆下盘中，这意味着 Straumsnutane 东部的 Ritscherflya 超群克拉通盖被部分淹没在下盘中，该巨型推覆在冈瓦纳合并期间形成，涉及 Kuunga 的 N 和 S Gondwana 碰撞造山运动，约 530-500 Ma 前。