关键词是指直接从文题或正文中抽取的词或词组，它主要有两个作用：（1）是文章的重要信息点，是文章的主题精华，供读者进行扫描阅读；（2）通过关键词进行检索查找文章和资料。现在地质信息院就编有主题词（包括关键词和叙词）表，查阅资料时，填写主题词表上需检索的词组， Keyword refers to the word or phrase extracted directly from the text or the text, it has two main roles: (1) is the important information point of the article, is the essence of the article for readers to scan the reading; (2) by Keyword search to find articles and information. Now the Geological Information Institute has compiled the key words (including key words and thesaurus) table, access to information, fill in the thesaurus need to retrieve the phrase,