Isostatic rebound, active faulting, and potential geomorphic effects in the Lake Lahontan basin, Nevada and California
Isostatic rebound, active faulting, and potential geomorphic effects in the Lake Lahontan basin, Nevada and California
复制标题
内华达州和加利福尼亚州拉洪坦湖盆地的等静压回弹、活动断层和潜在地貌效应
DOI：
10.1130/0016-7606(1999)111
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发表时间：
1999
影响因子：
4.9
通讯作者：
B. Bills
中科院分区：
文献类型：
--
作者：
K. D. Adams;S. Wesnousky;B. Bills
拉洪坦盆地晚更新世（Sehoo）湖的高岸线被用作被动应变标志，以描绘13 ka以来区域变形的幅度和特征。170个高海岸线地点的海拔记录表明，曾经水平（等位）的海岸线几乎横跨纬度4°和经度3°，现在垂直偏转约22米。大部分的变形是由于均衡反弹，但一个小的下向北的区域倾斜也似乎有助于整体的变形模式。活动断裂局部抵消高海岸线，但不能解释区域隆起归因于均衡反弹，因为13 ka。初步模型的反弹产生的上地幔粘度为10 - 18 Pa·s，这意味着麦克斯韦弛豫时间约300年。地球的快速反应，加上更新世末期湖平面的快速下降，可能已经将流入盆地的一些主要河流从一个终端子盆地转移到另一个终端子盆地。反弹引起的区域变形也可能控制了蜂蜜湖的现在位置。因此，这些海岸线数据支持了连接的可能性，
The high shoreline of the late Pleistocene (Sehoo) lake in the Lahontan basin is used as a passive strain marker to delineate the magnitude and character of regional deformation since 13 ka. The elevations of 170 high shoreline sites document that the once horizontal (equipotential) shoreline, which traverses almost 4° of latitude and 3° of longitude, is now deflected vertically about 22 m. Most of the deformation is attributed to isostatic rebound, but a small down-to-the-north regional tilting also appears to contribute to the overall deformation pattern. Active faults locally offset the high shoreline, but cannot explain the regional upwarping attributed to isostatic rebound since 13 ka. Preliminary models of the rebound yield an upper mantle viscosity of 10 18 Pa s that implies a Maxwell relaxation time of about 300 yr. The rapid Earth response, coupled with the rapid fall in lake level at the end of Pleistocene time, may have acted to divert some of the major rivers flowing into the basin from one terminal subbasin to another. The regional deformation caused by the rebound may also have acted to control the present location of Honey Lake. These shoreline data, therefore, support the potential for a link be