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本文叙述了阿得雷德地槽北部时限为 850～570百万年沉税岩和火山岩的古地磁研究成果。这些资料取自连续的地层剖面,但缺乏绝对年龄控制。褶皱检验和野外关系使笔者能够勾划出该时期相对简单和连续的视极移轨迹。原生磁化作用按年代可分为四个部分。自老到新:乌尔坦纳火山岩(λ=62S,φ=344 E;dp=16°,dm=18°);麦岭济纳冰碛岩(λ=45S,φ=346E,dp=06°,dm=11°),安捷派纳组(λ=33S,φ=344 E,dp=09°,dm=16°);布拉钦纳组(λ=33S,φ328E,dp=12°,dm=20°),业已鉴别出可能为早寒武世—奥陶纪的次生磁化作用有:乌尔坦纳火山岩(λ=36N,φ=087E,dp=13°,dm=26°),科普莱石英岩(λ=36S,φ=010E,dp=07°,dm=15°),麦岭济纳冰债岩(λ=01S,φ=065E,dp=08°,dm=14°),塔普莱山组(λ=33S,φ=344E,dp=08°,dm=15°),布耶劳组(λ=07S,φ=017E,dp=09°,dm=14°)。所研究的许多地层单元还可能存在第三纪或中生代的次生磁化作用。结合阿得雷德地槽南部古地磁研究成果,新资料证明,自中元古代以来,阿得雷德地槽没有发生明显的隆曲,地槽内的特殊S形构造是原生构造特征。新资料除能够阐述和澄清东南构造岩块的晚前寒武纪视极移轨迹史之外,还证实阿得雷德地槽的沉积作用在阿得雷德时期是发生于中至低纬度,因此证实该区晚前寒武纪冰川(或冰川海洋)沉积作用处于低纬度。
This paper describes the paleomagnetic study of the tax-destroying rocks and volcanic rocks with the northern limit of Adelaide Trough 850 ~ 570 million years. These data are taken from successive stratigraphic profiles but lack absolute age control. Fold test and field relationship enable the author to delineate the relatively simple and continuous apparent trajectory during this period. Primary magnetization by age can be divided into four parts. From old to new: Utahiner volcanic rocks (λ = 62S, φ = 344 E; dp = 16 °, dm = 18 °); the Maolingjina moraine rocks (λ = 45S, φ = 346E, dp = (Λ = 33S, φ = 344 E, dp = 09 °, dm = 16 °); Brachena group (λ = 33S, φ328E, dp = 12 °) , dm = 20 °), the secondary magnetization that may be identified as Early Cambrian-Ordovician has been identified as: Utahiner volcanics (λ = 36N, φ = 087E, dp = 13 °, dm = 26 ° ), Coleble quartzite (λ = 36S, φ = 010E, dp = 07 °, dm = 15 °) (Λ = 07S, φ = 017E, dp = 09 °, dm = 14 °) in the Tapre Mountains group (λ = 33S, φ = 344E, dp = . Many stratigraphic units under study may also have secondary magnetization of the Tertiary or Mesozoic. According to the results of the paleomagnetic study in the southern Adelaide Gully, new data prove that there has been no obvious uplift in the Adelaide Gully since the Mesoproterozoic, and the special S-shaped structure in the Gully is a native structural feature. In addition to being able to elucidate and clarify the history of the late Precambrian photopic shift trajectories of southeast structural blocks, the new data also confirm that the sedimentation of the Adelaide terrane occurred during the Adelaide period at mid-lower latitudes, Therefore, it is confirmed that the deposition of late Precambrian glaciers (or glaciers and oceans) in the area is at low latitudes.