流紋岩是火山的酸性噴出岩石，其岩體中的二氧化矽大於66％，由黏稠的熔岩冷卻而成。因為這種熔岩流動性較慢，常會堵住火山口，導致氣體壓力的積滯，最後以爆炸性的力量從火口中噴出。流紋岩屬於酸性的岩質，常以岩脈的方式入侵，此種岩石在澎湖僅見於花嶼。花嶼火山的活動年代，可能在中生代晚期之白堊紀或侏儸紀中期，又經過熱水換質作用，顏色多變，包括灰黃、綠色、灰紫色和灰白色等，有斑狀和流紋狀結構。其化學成分和花崗岩相同，部分由於形成時冷卻速度較快，使礦物來不及結晶，有玻璃光澤，也有解理。本中心收藏之標本採集自花嶼。
流紋岩是火山的酸性噴出岩石，其岩體中的二氧化矽大於66％，由黏稠的熔岩冷卻而成。因為這種熔岩流動性較慢，常會堵住火山口，導致氣體壓力的積滯，最後以爆炸性的力量從火口中噴出。流紋岩屬於酸性的岩質，常以岩脈的方式入侵，此種岩石在澎湖僅見於花嶼。花嶼火山的活動年代，可能在中生代晚期之白堊紀或侏儸紀中期，又經過熱水換質作用，顏色多變，包括灰黃、綠色、灰紫色和灰白色等，有斑狀和流紋狀結構。其化學成分和花崗岩相同，部分由於形成時冷卻速度較快，使礦物來不及結晶，有玻璃光澤，也有解理。本中心收藏之標本採集自花嶼。
Rhyolite is a volcanic acid extrusive rock whose mass is greater than 66 silicaformed from the cooling of viscous lava. Because this lava flows slowly, it often blocks the crater, causing a build-up of gas pressurefinally ejecting from the crater with explosive force. Rhyolite is an acidic rock that often invades in the form of dikes. This kind of rock is only found in Huayu in Penghu. The active age of Huayu volcano may have been in the Cretaceous period of the late Mesozoicthe mid-Jurassic period,after the effect of hot water mass exchange, rhyolite has mottledrhyolite structures with a variety of colors, including gray-yellow, green, gray-purplegray-white. Its chemical composition is the same as that of granite. Part of it has vitreous lustercleavage due to its rapid cooling rate during formation, making the minerals too late to crystallize. The specimens collected by this center are from Huayu.
