OPTICALLY STIMULATED LUMINESCENCE DATING OF GRAVELLY ALLUVIAL FAN DEPOSITS: LINKS BETWEEN CLIMATE AND GEOMORPHIC RESPONSE IN THE LOST RIVER RANGE, IDAHO By
نویسندگان
چکیده
............................................................................................................................ vi LIST OF TABLES .................................................................................................................. xii LIST OF FIGURES ............................................................................................................... xvi CHAPTER ONE: LUMINESCENCE DATING WITHOUT SAND LENSES – AN APPLICATION OF OSL TO COARSE-GRAINED ALLUVIAL FAN DEPOSITS OF THE LOST RIVER RANGE, IDAHO, USA ........................................................................... 1 1.1 Abstract .................................................................................................................. 1 1.2 Introduction ............................................................................................................ 2 1.2.1 Regional Setting ...................................................................................... 5 1.3 Methods................................................................................................................ 11 1.3.1 Sample Collection and Preparation ....................................................... 11 1.3.2 Dosimetry .............................................................................................. 13 1.3.3 Equivalent Dose Measurements ............................................................ 15 1.3.4 Calculation of Ages and Errors ............................................................. 20 1.4 Results and Discussion ........................................................................................ 21 1.4.1 Dosimetry .............................................................................................. 21 1.4.2 Equivalent Dose Results ....................................................................... 30 1.4.3 Analysis of Resulting Age Estimates .................................................... 36 1.5 Conclusions .......................................................................................................... 46
منابع مشابه
Vegetative and Climatic Controls on Holocene Wildfire and Erosion Recorded in Alluvial Fans of the Middle Fork Salmon River, Idaho
The Middle Fork Salmon River watershed spans high-elevation mixed-conifer forests to lowerelevation shrub-steppe. In recent decades, runoff from severely burned hillslopes has generated large debris flows in steep tributary drainages. These flows incised alluvial fans along the mainstem river, where charcoal-rich debris-flow and sheetflood deposits preserve a record of latest Pleistocene to Hol...
متن کاملRock varnish microlamination dating of late Quaternary geomorphic features in the drylands of western USA
Varnish microlamination (VML) dating is a correlative age determination technique that can be used to date and correlate various geomorphic features in deserts. In this study, we establish a generalized late Quaternary (i.e., 0–300 ka) varnish layering sequence for the drylands of western USA and tentatively correlate it with the SPECMAP oxygen isotope record. We then use this climatically corr...
متن کاملLate Holocene Relationships Among Fire, Climate, and Vegetation in Rangeland Ecosystems of Southwestern Idaho
Rangelands are characterized by more arid climates than forested regions; therefore, establishing fire histories using traditional methods (e.g. fire-scars from trees or charcoal in lake sediments) is problematic. This study uses radiocarbon dating of charcoal preserved in alluvial fans and stream deposits to reconstruct a record of fire and geomorphic response in rangelands of southwestern Ida...
متن کاملThe study of the role of Quaternary tectonic and climatic factors on the geomorphological evolution of Meshkin Shahr depression fan systems
Aims & Backgrounds: The Quaternary period is considered as the interval of climatic oscillations (glacial and interglacial) coupled with tectonic episodes. Therefore, tectonics and climate have simultaneously governed the evolution of Quaternary alluvial fans. Unraveling the tectonic and climatic factors under varied depositional systems is therefore the fundamental issue in understanding the e...
متن کاملCosmogenic He age estimates of Plio-Pleistocene alluvial-fan surfaces in the Lower Colorado River Corridor, Arizona, USA
a r t i c l e i n f o Keywords: Colorado River basalt cosmogenic 3 He surface exposure ages climate change desert pavement desert alluvial fans southwest USA geomorphology Plio-Pleistocene deposits of the Lower Colorado River (LCR) and tributary alluvial fans emanating from the Black Mountains near Golden Shores, Arizona record six cycles of Late Cenozoic aggradation and incision of the LCR and...
متن کامل