We reconstructed a chronology of glaciation spanning from the Late Pleistocene through the late Holocene for Fish Lake valley in the north-eastern Alaska Range using Be surface exposure dating and lichenometry. After it attained its maximum late Wisconsin extent, the Fish Lake valley glacier began to retreat ca. 16.5 ka, and then experienced a readvance or standstill at 11.6 0.3 ka. Evidence of...

Introduction: The likelihood that dissociating methane clathrate hydrate makes a significant contribution to martian atmospheric methane has been reported by [1-3]. The clathrate might be found in or beneath subsurface permafrost [1, 3-4], in surface ice such as glacial remnants [2], or, as reported here, in icy sediments. These reports suggest that triggers for clath-rate dissociation in recen...

Glacial landforms on Mars, including concentric crater fill (CCF), lineated valley fill (LVF), and lobate debris aprons (LDA), were mapped between~±30 and 50° latitude, and geometric constraints were placed on the volume of these deposits based on their topography and relationship with host topography (e.g., massifs, valleys, and craters). LDA deposits were found to have the largest volume (2.6...

The valley of Bishop Creek, which drains part of the eastern fl ank of the Sierra Nevada, California, contains an unusually well-preserved set of middle to late Quaternary moraines. These deposits have been mapped by previous investigators, but they have not been quantitatively dated. We used the accumulation of cosmogenic 36Cl to assign a chronology to the maximal glacial positions mapped in t...

In his writings John Lubbock expounded views on the understanding of past climates, prehistoric faunas, early humans, and the evolution of landscape and river systems. His contributions on some of these related topics are scarcely remembered, despite comparison with modern thinking showing them frequently to have been prescient. He visited the Somme valley, observing river terrace gravels and P...

Dismemberment of the preglacial Teays Valley system and development of the present Ohio River valley began in late Tertiary or early Pleistocene. By Illinoian time the present Ohio River was largely established in its present course, except for its headwaters above mile 114, which still flowed northward. The Illinoian glacial advance into northwestern Pennsylvania caused diversion of this porti...

An 40Ar/39Ar chronology of in-situ to near insitu volcanic ashfall deposits indicates that the surficial stratigraphy of Arena Valley extends back at least to middleMiocene time. Wet-based glacial ice occupied part of Arena Valley more than 11.3 Ma ago. Thick, northeast-flowing ice subsequently engulfed Arena Valley, again more than 11.3 Ma ago. Only minor glacier expansion occurred during Plio...

Glacial reworking of paraglacial rock slope material has been inferred from long-deglaciated terrains to be an important component of glacial sediment transfer. We provide the first description from a contemporary glacial environment of the geomorphological consequences of glacier advance (of the Feegletscher Nord, Switzerland) across a paraglacial rock avalanche deposit. The landform-sediment ...