CHARACTERISTICS OF THE GLACIERS IN THE JAPANESE ALPS

Glaciations during the Last Glacial in the Japanese Alps can be classified into two types: one is "azonal glaciation" and the other is "zonal glaciation". The ELAg (geomorphological equilibrium line altitude) of each former type glacier is determined by the Hs (maximum altitude of the mountain ridge), and forced to depress by the microclimatological phenomena such as drifted snow. The vertical / horizontal distribution of this type of glaciers is azonal and sporadic. On the other hand, the ELAg of latter type glaciers remains constant with the Hs, and reflects the regional air temperature. In the case, the mountain ridge is higher than the regional equilibrium-line altitude, the vertical / horizontal distribution of glaciers belonging to this type becomes zonal and continuous. Modern examples of these two types of glaciations can be found in Kamchatka Peninsula, the Altai Mountains, and the Caucasus Mountains. These facts suggest that this classification is applicable to spatial and temporal variations of glaciations. Most of the Last Glacial glaciers in the Japanese Alps are classified into "azonal glaciation" type. The glaciers belonging to "zonal glaciation" type ware located in the Northern Japanese Alps that have high altitude. It is found that some of "zonal glaciation" existed during the Last Glacial Maximum stage were changed to "azonal glaciation" type during the Late Glacial stage. From this point of view, the Last Glacial glaciers in the Japanese Alps existed as a spatio-temporal transition between these two types. To pay attention to the "azonal glaciation" that is controlled by the local conditions is important for the reconstruction of palaeoclimate based on the glacial landforms and their ELAs.