Biostratigraphic Units and Tectonism in the Mid-Cretaceous Foreland of Wyoming, Colorado, and Adjoining Areas: Part III. Middle Rocky Mountains
Biostratigraphic Units and Tectonism in the Mid-Cretaceous Foreland of Wyoming, Colorado, and Adjoining Areas: Part III. Middle Rocky Mountains
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怀俄明州、科罗拉多州和邻近地区白垩纪中期前陆的生物地层单元和构造作用：第三部分。
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发表时间：
1986
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影响因子：
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通讯作者：
W. A. Cobban
中科院分区：
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作者：
E. A. Merewether;W. A. Cobban
落基山脉中部中白垩世地层的年代学单元和不整合面表明，在塞诺曼期、土尔onian期和Coniacian期（88-96 m.g o . ago），西部内陆广泛存在海侵和海退，前陆也有反复的变形。广泛认可的Cenomanian-early Turonian海侵、middle Turonian海退和late Turonian- coniacian海侵的地层记录在几个地区被轻微的隆起和伴随的侵蚀事件所修正。最明显的构造运动发生在西蒙大拿州，在Cenomanian时期中晚期（93-94年前）；早Turonian-早中期Turonian（90-91年前）期间在怀俄明州西部及邻近地区；在Turonian晚期早期的科罗拉多州中北部、怀俄明州东部和怀俄明州西北部（89.8万年前）；科罗拉多州东北部、怀俄明州和蒙大拿州西南部的Turonian晚期（89.3万年前）。大部分涌浪的波峰线趋向于西北或东北方向。中白垩世前陆的构造运动与怀俄明州西南部和爱达荷州东南部的塞维尔造山带的逆冲运动相对应。此外，大部分前陆变形可能反映了逆冲带的东冲活动。
Chronolithologic units and unconformities in mid-Cretaceous formations of the central Rocky Mountains region indicate widespread marine transgressions and regressions as well as recurrent deformation of the foreland in the Western Interior during Cenomanian, Turonian, and Coniacian time (88-96 m.y. ago). The stratigraphic record of the widely recognized Cenomanian-early Turonian transgression, middle Turonian regression, and late Turonian-Coniacian transgression was modified in several areas by episodes of slight uplift and attendant erosion. The most evident tectonism was in western Montana during middle to late Cenomanian time (93-94 m.y. ago); in western Wyoming and adjoining areas during the early Turonian-earliest middle Turonian (90-91 m.y. ago); in north-central Co orado, eastern Wyoming, and northwestern Wyoming in the early late Turonian (89.8 m.y. ago); and in northeastern Colorado, Wyoming, and southwestern Montana in the late late Turonian (89.3 m.y. ago). Crestlines of most of the swells trend generally either northwest or northeast. The tectonism of the mid-Cretaceous foreland corresponds in age to displacements of thrusts in the Sevier orogenic belt of southwestern Wyoming and southeastern Idaho. Furthermore, much of the foreland deformation probably reflects episodes of eastward thrusting in the thrust belt.