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美国科罗拉多高原Paradox盆地中的裂口盐墙和盐背斜,主要是在古生界和中生界沉积物的差异负载作用下发育起来的。盐构造顶部的平缓褶皱,通常被认为是晚白垩纪至古新世拉腊米挤压运动的产物,而其脊顶地堑与山谷,则被认为是挤压后的松弛拉伸及盐溶作用所造成的。基于野外调查、物理模拟以及现代盐构造学理论,研究认为这些平缓褶皱和脊顶地堑,主要是新生代始新世至渐新世北北东向区域拉伸作用的产物。因为岩盐较其围岩软弱,拉伸形变主要集中在早先形成的盐墙、盐背斜及其较薄的顶板中,使盐构造发生活化并形成新的拉伸构造。顶板中的拉伸构造主要包括正断层、地堑、断层滑移(断滑)褶皱以及滚动褶皱。由于区域拉伸方向斜交盐构造走向,断层分布多呈羽列状。在母盐层较厚地区,拉伸使盐刺穿在正断层之下次动上升;而在母盐层较薄地区,拉伸使盐刺穿下降。在初始盐刺穿较高地区,盐构造的侧翼下降;而在初始盐刺穿较低地区,盐构造整体下降。拉伸使盐刺穿变宽,脊顶地堑下沉,形成拉伸型下降盐刺穿特征性的尖角盐体构造。局部地区,盐体从破碎的顶板间溢出,覆盖了下沉的脊顶地堑。
Rift salt walls and salt anticlines in the Paradox basin of the Colorado Plateau are mainly developed under the differential loading of Paleozoic and Mesozoic sediments. The gentle folds at the top of the salt structure are generally thought to be the product of Late Cretaceous to Paleocene Laramie thrusting and the ridge-top graben and valleys are thought to be post-extrusion relaxed stretch and saline Caused by Based on the field investigation, physical simulation and modern salt tectonics, it is considered that these gentle folds and crest graben are mainly derived from the tensile action of Cenozoic Eocene to Oligocene in the NE direction. Because rock salt is weaker than its surrounding rock, the tensile deformation is mainly concentrated in the previously formed salt wall, salt anticline and its thinner roof, activating the salt structure and forming a new tensile structure. Tensile structures in the roof mainly include normal faults, grabens, fault slip faults and rolling folds. Due to the diagonal salt tectonic strike in the direction of regional stretching, the faults are mostly plume-like. In areas with thick mother salt strata, stretching causes the salt piercing to move a second time up the normal fault, whereas in areas where the parent salt strata are thin, stretching causes the salt piercing to drop. In the area where the initial salt piercing is higher, the tectonism of the salt structure descends; in the area where the initial salt piercing is lower, the salt structure decreases overall. Stretching to broaden the salt piercing, ridge top graben subsidence, the formation of tensile descending salt piercing characteristic sharp salt body structure. In some areas, salt spills from the broken roof, covering the sunken graben.