灰岩又称石灰岩，是以方解石为主要成分的碳酸盐岩。硬度一般不大，与稀盐酸有剧烈的化学反应。灰岩是东兰国家地质公园喀斯特地貌形成的主要原因，也是农业、工业、化工及建筑行业重要的生产原料。 Limestone is a kind of carbonate rock mainly composed of calcite, Which is generally not very hard but can have a intense chemical reaction with dilute hydrochloric acid. Limstone is the major reason of forming karst landform in Donglan National Geopark, and it is also important raw materials for agriculture, industry, chemical industry and building trade.