Growth of the Huoerguosi anticline (north Tianshan Mountains) by limb rotation since the late Miocene

Huoerguosi 背斜，在北方 Tianshan 山山麓 fold-and-thrust 带定位了，是 trending 东方西方差错相关的褶层。在沿着 Jingou 河的生气的节，它的南方手足由 Anjihaihe 的生长前阶层组成( E ( 2-3 )一)， Shawan (( E-3-N-1 ) s )， Taxihe ( N ( 1 ) t )和 Dushanzi ( N ( 2 ) d )的更低的部分形成， trending 东方西方并且蘸到南方 55 学位，并且 Dushanzi ( N ( 2 ) d )和 Xiyu 的上面的部分的生长阶层(( N-2-Q ( 1 )) x )形成，哪个在 Xiyu 的底部在生长阶层的底从 55 个学位减少到 47 个学位的剧降(( N-2-Q ( 1 )) x )形成到类似于在 Xiyu 的顶的 0 个学位(( N-2-Q ( 1 )) x )形成。在背斜的北方手足的阶层垂直或打翻，并且被突破戳切导致 drag 褶层。深入地，背斜是对称的，并且它的核心包括白垩纪和侏罗记忍受煤的床。在地震侧面，在背斜的南方手足的生长前阶层的地震反射镜常常蘸到南方，并且生长阶层之一扇向南方，谁的向上蘸减少。沿着 Jingou 河山谷和在地震侧面显示出的背斜的深结构的南方手足生长阶层 outcropped 的几何学显示 Huoerguosi 背斜是由手足旋转成长的分开褶层背斜。基于生长模型和 magnetostratigraphic 年龄，在 Huoerguosi 背斜的成长过程期间，南方手足吸收的平均弄短率类似于 0.46 mm/a ，和背斜的平均高举率类似于超过平均免职率的 0.86 mm/a ，它根据背斜的顶强烈地被侵蚀的事实。考虑 Huoerguosi 背斜的对称的几何学并且忽略突破推进，整个背斜弄短应该非常类似于 0.92 mm/a，加倍在南方手足从生长决定的弄短的率。

The Huoerguosi anticline, located in the north Tianshan Mountains piedmont fold-and-thrust belt, is a trending east-west fault-related fold. In the cross section along the Jingou River, its south limb is composed of the pre-growth strata of the Anjihaihe （E2.3a）, the Shawan （（E3-N1）s）, the Taxihe （N1t） and the lower part of the Dushanzi （N2d） Formations, trending east-west and dipping to south 55°, and the growth strata of the upper part of the Dushanzi （N2d） and Xiyu （（N2-Q1）x） Formations, dips of which decrease from 55° at the base of the growth strata to 47° at the bottom of the Xiyu （（N2-Q1）x） Formation to -0° at the top of the Xiyu （（N2-Q1）x） Formation. The strata at the north limb of the anticline are vertical or over-turned, and are cut by the breakthrough thrusts to result in the drag fold. In the depth, the anticline is symmetric, and its core comprises the Cretaceous and the Jurassic coal-bearing beds. In the seismic profile, the seismic reflectors of pre-growth strata at the south limb of the anticline dip to south constantly, and ones of the growth strata fan southward, whose dips decrease upward. The geometry of the south limb growth strata outcropped along the Jingou River valley and the deep structure of the anticline shown in the seismic profile indicate that the Huoerguosi anticline is a detachment fold anticline growing by limb rotation. Based on the growth model and magnetostratigraphic age, during the growing process of the Huoerguosi anticline, the average shortening rate absorbed by the south limb is -0.46 mm/a, and the average uplifting rate of the anticline is -0.86 mm/a which exceeds the average deposition rate, which is in accordance with the fact that the top of the anticline is intensely eroded. Considering symmetric geometry of the Huoerguosi anticline and ignoring the breakthrough thrusts, the shortening of the whole anticline should be more than -0.92 mm/a, doubling the shortening rate determined from the growth at the south limb.