Chemical evolution of shallow playa groundwater in response to post-pluvial isostatic rebound, Honey Lake Basin, California–Nevada, USA     

Alan L. Mayo  Rachel M. Henderson  David Tingey  William Webber 《Hydrogeology Journal》2010,18(3):725-747

The 1,750-km² endorheic Honey Lake basin (California–Nevada, USA) was part of the 22,000-km² Pleistocene Lake Lahontan pluvial lake system which existed between 5,000 and 40,000 years BP. The basin consists of two subbasins separated by a low elevation divide. Groundwater in the western subbasin has a maximum total dissolved solids (TDS) content of only ～1,300 mg/L; however eastern subbasin groundwater has a maximum TDS of ～46,000 mg/L. This TDS distribution is unexpected because 94% of surface water TDS loading is to the western subbasin. In situ reactions and upwelling thermal groundwater contributing to groundwater chemistry were modeled using NETPATH. The TDS difference between the subbasins is attributed to post-Lake Lahontan isostatic rebound about 13,000 years ago. Prior to rebound the subbasins did not exist and the low point of the basin was in the eastern area where hydraulic isolation from the larger Lake Lahontan and frequent desiccation of the basin surface water resulted in evaporite mineral deposition in accumulating sediments. After rebound, the terminal sink for most surface water shifted to the western subbasin. Although most closed basins have not been impacted by isostatic rebound, results of this investigation demonstrate how tectonic evolution can impact the distribution of soluble minerals accumulating in shallow basins.  相似文献   

A gravity survey of Northwest Lancashire     

R. D. Barker 《Geological Journal》1974,9(1):29-38

A survey involving 860 gravity measurements over the Fylde area of Lancashire is described. A line of movement in the pre-Permian basement rocks is shown to cross the area from north north east to south south west forming the eastern edge of a deep sedimentary basin. Displacement of the Carboniferous along this line has reached 1000 m in places and was probably an important influence on Permo-Triassic deposition in Northwest Lancashire.  相似文献