Testing the use of feldspars for optical dating of hurricane overwash deposits |
| |
| Authors: | F Davids GAT Duller HM Roberts |
| |
| Institution: | Aberystwyth Luminescence Research Laboratory, Institute of Geography & Earth Sciences, Aberystwyth University, Llandinam Building, Aberystwyth, Ceredigion SY23 3DB, United Kingdom |
| |
| Abstract: | The geological record preserved in coastal salt marshes provides an opportunity to determine past hurricane activity during the Late Holocene in New England, USA. High precision dating is important to correlate overwash sand layers associated with hurricane strikes between different sites along the coastline. Three different optical dating methods have been tested and compared with independent age control; i) optically stimulated luminescence from quartz, ii) infrared stimulated luminescence from K-feldspar, and iii) a subtraction method.Quartz and K-feldspar dating results for three samples in a core from Round Hill Beach Marsh are in stratigraphic order and they are consistent within errors with radiocarbon ages and with each other. Subtraction dating results agreed with the quartz and K-feldspar ages for two of the three samples, but the subtraction age of the youngest sample gave an age underestimate. Replicate equivalent dose values from quartz showed a larger variation than those from feldspars, and this resulted in larger errors for the quartz and subtraction ages than those based on feldspars. K-feldspar yields the most precise optical ages, but is complicated by the need to correct for anomalous fading. Both quartz and K-feldspar are suitable for optical dating of hurricane overwash deposits in New England. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
