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Ecological Subsections of Glacier Bay National Park & Preserve, Klondike Gold Rush National Historic Park, & Sitka National Historic Park Ecological Subsections of Southeast Alaska and Neighboring Areas of Canada; Technical Publication R10-TP-75

A hierarchical classification for subsections was created to reflect developmental histories of terrestrial surfaces of Southeast Alaska (Table 2). Three terrain classes were distinguished at the first level. Subsections currently affected by glacial processes (ice accumulation and movement, meltwater streams with heavy bedloads, deglaciated areas of primary succession) were classified as active glacial terrains. Older surfaces developing after the retreat of continental ice (=14,000 years ago) fell into the inactive glacial terrain class. The majority of subsections occurred in this category. Subsections resulting from post-glacial processes not related to glaciation (i.e., volcanism) were classified as post-glacial terrains. These three classes were then divided by physiography. This second level was further subdivided by lithology and surficial geology (referred to as geologic classes) to form a third hierarchical tier.

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עדכון אחרון דצמבר 17, 2019, 10:37 (AKST)
נוצר ב דצמבר 17, 2019, 10:37 (AKST)
סטטוס Complete
Start Date 2000-01-01
End Date 2001-10-01