Tangshan area, complicated in regionalstructures which result in frequent engineering problems and earthquakes, is relatively unstable in its regional crust.
唐山地区区域构造复杂，工程地质问题众多，地震频繁，总体看来唐山地区区域地壳稳定性相对较差。
2
Regionalstructures control the distribution of gold metallogenic belts, and different structural units control different types of ore-controlling structures.
区域构造格局控制成矿带的分布，不同构造单元具有不同的控矿构造型式。
3
Hilar and mediastinal adenopathy can compromise regionalstructures such as the superior vena cava or trachea and potentially cause a life-threatening complication.