冀北超基性岩地质特征

Geological Charateristics of Ultrabasicrocks in Northern Hebei Province

冀北超基性岩带位于华北地台北缘，受崇礼－隆化深大断裂控制。该岩带从西往东可分为赤城、丰宁－滦平和承德－平泉三个超基性岩群。各岩群的形态、产状、岩石类型、矿物成份、化学成份各有特点，表现出一定的规律性。Ｋ－Ａｒ及Ｓｍ－Ｎｄ同位素年龄表明，这些超基性告形成于中元古宙、海西期及印支期。

orthern Hebei Ultrabasicrock zone, dominated by the Chongli-Longhua deep-majorfracture is situated at the northern margin of North China plate form. This Ultrabasic rock zonecan be further divided from west to east into three rock groups: Chicheng, Fengning-Luanpingand Chengde-Pingquan Ultrabasic rock groups. The shapes, occurences, rock types, mineral components and Petrochemical components of three ultrabasic rock groups all have different characteristics and show certain regularities. K-Ar and Sin-Nd isotope datings show that these ultrabasic rocks are formed in Mid-Proterozoic era, Caledonian epoch and Hercynian epoch.