论文部分内容阅读
前言前震旦纪岩层在中国华北和东北出露较广,包含了不同的变质杂岩、混合岩杂岩和岩浆岩类,蕴藏着铁、菱镁矿、金、铜、滑石、硼、磷、云母、铬等许多矿产以及一部分稀有分散元素和不同种类的晚期内生矿床,经历了漫长而复杂的地质发展史。因此,研究本区前震旦纪地质,不但具有重大的实际意义,同时对于地质科学理论的丰富和提高,也将作出重要的贡献。本文所涉及的地区西起东经107°附近,南界约在北纬33°30′—34°。它包括了“中国地台”的大部分(见附图)。
Foreword Pre-Sinian strata are widely exposed in North China and Northeast China, and contain different metamorphic complexes, mixed rock complexes and magmatic rocks. They contain iron, magnesite, gold, copper, talc, boron, phosphorus, Mica, chrome and many other minerals, as well as part of the rare scattered elements and different types of late endogenous deposits, has experienced a long and complex history of geological development. Therefore, studying the pre-Sinian geology in this area is not only of great practical significance, but also will make an important contribution to the enrichment and enhancement of the theory of geosciences. The area covered by this paper is about 107 ° east longitude and about 33 ° 30’-34 ° north latitude. It includes most of the “China Platform” (see photo).