The early Paleozoic Terskey Suture zone, located in the southern part of the Northern Tien Shan domain in Kyrgyzstan, comprises tectonic slivers of dismembered ophiolites and associated primitive volcanics and deep-marine sediments. In the Lake Songkul area, early-middle Cambrian pillow basalts are crosscut by the Songkultau intrusion of coarse-grained gneissose quartz diorites and tonalites with geochemical characteristics typical for high-SiO₂ adakites (SiO₂ ​> ​56 ​wt.%, Al₂O₃ ​> ​15 ​wt.%, Na₂O ​> ​3.5 ​wt.% and high Sr/Y and La/Yb ratios). The Songkultau granitoids have positive initial ε_Nd (+3.8 to +6.4) and ε_Hf (+12.3 to +13.5) values indicating derivation from sources with MORB-like isotopic signature. Volcanic formations, surrounding the Songkultau intrusion, have geochemical affinities varying from ocean floor to island arc series. This rock assemblage is interpreted as a relic of an early-middle Cambrian primitive arc where the adakite-like granitoids were derived from partial melting of young and hot subducted oceanic crust. An age of 505 ​Ma, obtained for the Songkultau intrusion, shows that hot subduction under the Northern Tien Shan continued until middle Cambrian. The primitive arc complexes were obducted onto the Northern Tien Shan domain, where the Andean type continental magmatic arc developed in Cambrian and Ordovician. Formation of the Andean type arc was accompanied by uplift, erosion and deposition of coarse clastic sediments. A depositional age of ca. 470 Ma, obtained for the gravellites in the Lake Songkul area, is in agreement with the timing of deposition for lower Ordovician conglomerates elsewhere in the Northern Tien Shan, and corresponds to the main phase of the Andean type magmatism. The Songkultau adakites in association with surrounding ocean floor and island arc formations constitute a relic of a primitive Cambrian arc and represent a juvenile domain of substantial size identified so far within the predominantly crustal-derived terranes of Tien Shan. On a regional scale this primitive arc can be compared with juvenile Cambrian arcs of Kazakhstan, Gorny Altai and Mongolia.

早古生代的特斯基缝合带位于吉尔吉斯斯坦北天山地区的南部，包括碎裂的蛇绿岩及其相关的原始火山岩和深海沉积物的构造条带。在Songkul湖地区，早期的中寒武统枕玄武岩被Songkultau侵入，其粗粒状片麻质石英闪长岩和钠长石具有典型的高SiO _{2 2石}（SiO ₂  > 56 wt。％，Al ₂ O ₃  > 15 wt。％，Na ₂ O> 3.5 wt。％和高Sr / Y和La / Yb比）。所述Songkultau花岗岩具有正初始ε_的Nd（3.8至6.4）和ε_的Hf（+12.3至+13.5）值表示源自具有MORB样同位素特征的来源。Songkultau侵入体周围的火山岩层具有不同的地球化学亲和力，从海底到岛屿弧系列。这种岩石组合被解释为早中寒武纪原始弧形的遗迹，其中，类似于白云石的花岗岩是由年轻的和热的俯冲洋壳部分融化而得到的。Songkultau侵入带获得的505 Ma年龄表明，北天山下的热俯冲一直持续到中寒武纪。原始弧复合体被带到北天山地区，在寒武纪和奥陶纪发育了安第斯型大陆岩浆弧。安第斯型弧的形成伴随着粗碎屑沉积物的隆升，侵蚀和沉积。大约的沉积年龄。从松果湖地区的砾石中获得的470 Ma与北天山其他地方的奥陶纪下部砾岩的沉积时间一致，并且对应于安第斯型岩浆作用的主要阶段。与周围海床和岛弧地层相关联的宋库陶质石质构成了原始寒武纪弧线的遗迹，并代表了迄今为止在天山地壳起源的地层中确定的相当大的少年区域。在区域范围内，可以将这种原始弧与哈萨克斯坦，戈尔尼·阿尔泰和蒙古的少年寒武纪弧相比较。这与北天山其他地方的奥陶纪下部砾岩的沉积时间一致，并且对应于安第斯型岩浆作用的主要阶段。与周围海床和岛弧地层相关联的宋库陶质石质构成了原始寒武纪弧线的遗迹，并代表了迄今为止在天山地壳起源的地层中确定的相当大的少年区域。在区域范围内，可以将这种原始弧与哈萨克斯坦，戈尔尼·阿尔泰和蒙古的少年寒武纪弧相比较。这与北天山其他地方的奥陶纪下部砾岩的沉积时间一致，并且对应于安第斯型岩浆作用的主要阶段。与周围海床和岛弧地层相关联的宋库陶质石质构成了原始寒武纪弧线的遗迹，并代表了迄今为止在天山地壳起源的地层中确定的相当大的少年区域。在区域范围内，可以将这种原始弧与哈萨克斯坦，戈尔尼·阿尔泰和蒙古的少年寒武纪弧相比较。与周围海床和岛弧地层相关联的宋库陶质石质构成了原始寒武纪弧线的遗迹，并代表了迄今为止在天山地壳起源的地层中确定的相当大的少年区域。在区域范围内，可以将这种原始弧与哈萨克斯坦，戈尔尼·阿尔泰和蒙古的少年寒武纪弧相比较。与周围海床和岛弧地层相关联的宋库陶器，构成了原始寒武纪弧线的遗物，并代表了迄今在天山主要地壳衍生的地层中确定的相当大的少年区域。在区域范围内，可以将这种原始弧与哈萨克斯坦，戈尔尼·阿尔泰和蒙古的少年寒武纪弧相比较。