矽質玄武岩是澎湖島群的主要岩石,顏色灰黑至深灰微褐色,組成粒度為中晶至粗晶。組成礦物主要為斜長石、斜輝石及鈦鐵礦等。所含的二氧化矽較高,常大於49%。岩漿由上部地函物質部分熔融所產生,深度大約在34〜45公里間,平均溫度約在700〜900℃,當岩漿噴出後開始慢慢冷卻,由於礦物百分比的不同,才形成今日粗大寬廣的玄武岩柱,每一岩柱高約20公尺,直徑約1〜1.5公尺,例如虎井嶼和桶盤嶼的岩柱是澎湖群島中最具規模的,也最具特色之矽質玄武岩柱,表層由於氧化作用,形成棕紅的鐵鏽顏色。本中心收藏的標本來自馬公烏崁海崖。
矽質玄武岩是澎湖島群的主要岩石,顏色灰黑至深灰微褐色,組成粒度為中晶至粗晶。組成礦物主要為斜長石、斜輝石及鈦鐵礦等。所含的二氧化矽較高,常大於49%。岩漿由上部地函物質部分熔融所產生,深度大約在34〜45公里間,平均溫度約在700〜900℃,當岩漿噴出後開始慢慢冷卻,由於礦物百分比的不同,才形成今日粗大寬廣的玄武岩柱,每一岩柱高約20公尺,直徑約1〜1.5公尺,例如虎井嶼和桶盤嶼的岩柱是澎湖群島中最具規模的,也最具特色之矽質玄武岩柱,表層由於氧化作用,形成棕紅的鐵鏽顏色。本中心收藏的標本來自馬公烏崁海崖。
The siliceous basalt is the main rock of the Penghu Islands. Its color is gray-black to dark gray-brown. Its composition granularity is medium to coarse. Its main constituent minerals are plagioclase, oblique pyroxeneilmenite. Its silicon dioxide content is higher, often greater than 49. The lava is produced by the partial melting of the upper mantle material at a depth of about 34 to 45 kilometersat an average temperature of about 700 to 900 °C. After the lava is ejected, it begins to cool slowly. Due to the difference in the percentage of minerals, it forms today’s thickbroad basalt columns, each of which is about 20 meters highabout 1 to 1.5 meters in diameter. For example, in the Penghu Islands, the rock columns of Hujing IsletTongpan Islet are the largestmost characteristic siliceous basalt columns, whose surface layer is oxidized to form a brown-red rust color. The specimens collected by this center are from Wukan Sea Cliff of Magong City.