畠山唯達

北西オーストラリア, ピルバラ地塊, ノースポール地域の太古代層状チャート(約35億年)の古地磁気方位

Hatakeyama/Tadahiro

Paleomagnetic direction of banded chert in North Pole region(ca. 3.5Ga), Pilbara craton, north Western Australia


著者名 Authors 所属機関名 所属機関名(欧文)
1 #畠山唯達 Hatakeyama/Tadahiro 東京大学理学部地球惑星物理学教室 Dept. of Earth and Planetary Physics, Faculty of Science,
2 浜野/洋三 Hamano/Yozo 東京大学理学部地球惑星物理学教室 Dept. of Earth and Planetary Physics, Faculty of Science,

講演予稿:
 西オーストラリア, ピルバラ地塊東部ノースポール地域の層状チャ ート(35億年)について段階的熱消磁法によって安定な磁化の方向が 得られた. その結果は現代の磁場方向と大きく違い, またサイトに よって褶曲テストについて好意的な結果を示した.

abstract:
 Banded chert in North Pole region, Pilbara craton, Western Australia, was intruded and folded by a granitic batholith in 3.5 billion years ago. From the results of paleomagnetic measurements from two sites, which are located in the south (site A) and east (site B) of the granitic dome, with stepwise thermal demagnetization, it is indicated that the paleomagnetic directions of the samples from each site are far from the present field direction, that the directions of the two blocks form the site B is roughly antipodal, and that the difference of the directions between site A and B is smaller afterthe bedding correction than that before.

キーワード:
古地磁気,褶曲テスト,層状チャート,太古代

Keywords:
paleomagnetism, fold test, banded chert, Archean