@article{oai:niigata-u.repo.nii.ac.jp:00003209,
 author = {平原, 由香 and 周藤, 賢治},
 issue = {8},
 journal = {地質学雑誌, 地質学雑誌},
 month = {Aug},
 note = {The outcrop of the Cape Sukoton intrusion, a constituent of Miocene doleritic sill swarm in the northern part of Rebun Island, north Hokkaido, is 1,600×600m wide and more than 240m thick, and dips gently eastward. It can be lithologically divided into three zones；the upper Columnar Joint Zone, middle Banded Structure Zone, and lower Massive Zone. The appearance of columnar joints is remarkable in doleritic rocks of the Columnar Joint Zone. Banded structures and columnar joints are also well developed in the doleritic rocks of the Banded Structure Zone, whereas both banded structures and columnar joints are not observed in porphyrites of the Massive Zone. Based on structural analysis of columnar joints, lithological descriptions of rocks in each zone, and the presence of interlayered sillsediment structure at the boundary between the intrusion and sedimentary rocks, the Cape Sukoton intrusion is inferred to have formed in the following main three stage magmatic events. 1) first stage (formation of the Columnar Joint Zone) ；intrusion of a basaltic magma into wet and poorly consolidated sediments, and melanocratic to leucocratic dolerites and leucocratic andesitic veins were generated during subsequent cooling contraction and crystallization of magma, and columnar joints were formed throughout the body, 2) second stage (formation of the Banded Structure Zone) ； intrusion of a new basaltic magma into the Columnar Joint Zone and wet poorly consolidated sediments. During cooling of the magma, banded structures composed of stratified vesicular and non-vesicular layers have been formed in melanocratic dolerites, and 3) third stage (formation of the Massive Zone) ；intrusion of another magma into the Banded Structure Zone, prior to the complete cooling of the Banded Structure Zone. During the third stage, melanocratic dolerites of the Banded Structure Zone might have been brought into the intruding magma, which resulted in the appearance of melanocratic enclaves contained in the Massive Zone., 北部北海道，礼文島北部に分布する厚さ240mのシルである，スコトン岬貫入岩体は柱状節理帯，縞状構造帯，塊状帯に区分される．各帯は貫入関係である．柱状節理帯と縞状構造帯は，優黒質ドレライトと優白質ドレライトおよび安山岩質細脈よりなる．本岩体の形成は新第三系堆積岩類の浜中層の堆積時～堆積直後に柱状節理帯を形成したマグマの貫入により始まり，続いて縞状構造帯を形成したマグマが貫入した．両マグマとも冷却の進行に伴い，結晶分化作用により優黒質ドレライト，優白質ドレライト及び安山岩質細脈を形成し，冷却末期に柱状節理を形成した．縞状構造帯では柱状節理の形成前に優黒質ドレライト中に気孔の量比の違いによる縞状構造が発達した．最後に塊状帯を形成したマグマが縞状構造帯を形成したマグマの未固結時に貫入した．貫入したマグマ中に縞状構造帯の優黒質ドレライトの一部が取り込まれ，塊状帯中の暗色包有物を形成した．},
 pages = {442--458},
 title = {北海道礼文島、ドレライト質スコトン岬貫入岩体の内部構造と形成過程},
 volume = {109},
 year = {2003}
}