High Resolution Paleomagnetism and Magnetostratigraphy of Ferrar Volcanic rocks from the Southern Mesa Range (North Victoria Land, Antarctica)

大陆溢流玄武岩（CFB），如Karoo-Ferrar省，被解释为在不到1百万年的相对较短的时间内侵位在10公里左右的大陆区域。因此常常与大规模的自杀有关。早侏罗世的Karoo-Ferrar火山岩是否满足快速挤出的要求最近一直在争论，地质年代学数据表明火山活动的持续时间更长，可达600万年。如果这一更长的安置期是现实的，那么普莱恩巴赫纪末期的大灭绝是否与卡罗-费拉CFB有关就成了问题。考虑到早侏罗世地磁场显示出极高的反转率，任何跨度超过100万年的火山序列，应该记录至少一次，但可能更多，地球磁场的逆转。因此，计划对南极洲梅萨山脉的柯克帕特里克玄武岩进行古地磁研究，在那里，盖尔梅萨山脉中至少有40个火山流暴露，高度高达800米。早期研究的初步结果表明，有一个现实的机会，隔离初级磁化的概念被支持的存在下，未改变的玻璃在地面质量已被描述为这些岩石表明这些玄武岩的原始条件。我们的研究将通过确定古强度来补充。考虑到中生代的古强度数据库是非常小的，对提高数据密度的任何贡献是向前迈进了一大步，以更好地了解过去的地球发电机过程。

Continental Flood Basalts (CFB) such as the Karoo-Ferrar province are interpreted as having been emplaced over continental areas in the order of 10 km and within a relatively short period of time of less than 1m.y. and therefore are often linked to mass extinctions. Whether the Karoo-Ferrar volcanic rocks of early Jurassic age meet the requirement of rapid extrusion has recently been debated and geochronological data suggests a longer duration of the volcanic activity of up to 6 m.y. If this longer period of emplacement is realistic than it becomes questionable whether the end- Plienbachian mass extinction is linked to the Karro-Ferrar CFB at all. Taking into account that the early Jurassic geomagnetic field displays extremely high reversal rates, any volcanic sequence which spans more than 1m.y. should record at least one, but probably more, reversals of the Earth magnetic field. It is therefore planned to study paleomagnetically the Kirkpatrick basalts of Mesa Range, Antarctica, where at least 40 volcanic flows are exposed in the Gair Mesa a sequence of up to 800m in height. Preliminary results of earlier studies suggest that there is a realistic chance to isolate primary magnetizations a notion being supported by the presence of unaltered glass in the ground mass which has been described for these rocks indicates the pristine conditions of these basalts. Our studies will be complemented by the determination of paleointensities. Taking into account that the paleointensity data base for the Mesozoic is extremely small, any contribution towards improvement of data density represents a great step forward to a better understanding geodynamo processes in the past.