Discovery of especially large bubble-like miarolitic granites in Laoshan and its geological and geomorphic significance

摘要

Recently, some especially large bubble-like miarolitic caves in A-type granites in Laoshan have been discovered with the largest diameter of up to 3.1 m, far exceeding the granitic miarolitic caves previously reported, thus adding new knowledge to geology. This helps to study the primary environment for granites formed in Laoshan and also reveal genesis of “natural-mortar” micro-landform for granites in Laoshan. The existence of a new genesis type—“bubble-like miarolitic caves” of speleology is also confirmed by this discovery. Especially large bubble-like miarolitic caves are rare geological relics with high ornamental, science and tourism value.