分散流和次生晕是化探普查的两种主要方法,所采的样品是经过长期表生风化作用的产物,它包括了物理风化和化学风化.由于各种矿物(元素)地球化学性质的不同,以及由气候、植被、酸度、地形、地表堆积物来源等所制约和组成的景观地球化学条件的不同,各种元素的富集介质、层位、粒度、主要载体、存在状态、元素行为等都不同,因而必须有相适应的工作方法和分析手段,才能取得最清晰的、所需要的地球化学异常.从六十年代开始,许多国家相继开展了景观地球化学的研究,研究相应条件下各种次生异常的发育特征,确定相应的工作方法,扩大了化探工作领域,提高了找矿效果.如加拿大,六十年代中期开始结合本国冰碛物和湖泊发育的特点,研究了次生异常的发育特征和机制,制订了 Dispersed flow and secondary halo are the two main methods of geochemical survey, and the samples taken are the products of long-term weathering which include physical weathering and chemical weathering. Due to the geochemical properties of various minerals Different elements of the enrichment medium, horizon, grain size, main carrier, state of existence, and elemental behavior of the different types of landscape geochemical conditions controlled and composed of climate, vegetation, acidity, topography, sources of surface sediments, So they must have the appropriate working methods and analytical tools in order to obtain the clearest, the required geochemical anomalies from the sixties onwards, many countries have conducted a study of landscape geochemistry, the study under the appropriate conditions Various secondary anomalous developmental characteristics, to determine the corresponding working methods, expanding the field of geochemical exploration and improve the prospecting effect.As Canada, the mid-1960s combined with the characteristics of the national moraine and lake development, Developmental characteristics and mechanisms of abnormalities were developed