Development of 1.9 Ga Bear Creek Foredeep on Thermally YoungLithosphere

这项拟议的研究将考察Bear Creek ForeDeep由于未成熟的被动大陆边缘坍塌而在热年轻的大陆岩石圈上进化的可能性。研究将采用综合办法，将选定地区的地质和地质年代实地调查与Thelon构造带(推断缝合)相关重力异常的地球物理模型相结合，并对盆地-Thelon带系统进行二维模拟。模型将被用来对形成于冷和暖岩石圈上的盆地的盆地几何和地层结构做出一阶预测。然后将这些模型与Bear Creek ForeDeep的观测特征进行比较，作为评估盆地发展期间岩石圈热状况的一种方法。在Bear Creek ForeDeep下沉期间评估岩石圈的热年龄，是对被动大陆边缘平均而言可能比年轻时期更短暂的假设的关键检验(参见。霍夫曼和鲍林，1984)。

The proposed research will examine the possibility that Bear Creek Foredeep evolved on thermally young continental lithosphere as a result of collapse of an immature passive continental margin. Research will involve an integrated approach, combining geological and geochronological field investigations of selected areas with geophysical modelling of related gravity anomalies the Thelon Tectonic Zone (infered suture) and two-dimensional modelling of the basin - Thelon Zone system. Models will be used to make first-order predictions concerning basin geometry and stratigraphic architecture of basins formed on cold vs. warm lithosphere. The models will then be compared to the observed characteristics of Bear Creek Foredeep as a method of evaluating the thermal condition of the lithosphere during basin development. Evaluating the thermal age of the lithosphere during subsidence of Bear Creek Foredeep constitutes a critical test of the hypothesis that passive continental margins may have been, on the average, more short-lived than in younger times (cf. Hoffman and Bowring, 1984).