一地区沉积了一套岩层后,受地壳运动影响而升出水面,沉积作用发生中断,遭受剥蚀,然后再次下沉接受沉积,地层无倾斜或反转,则地层接触关系为 ( )
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
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