Tree-ring dates on two pre-Little Ice Age advances in Glacier Bay National Park and Preserve, Alaska, USA |
| |
Authors: | Gregory C Wiles Daniel E Lawson Eva Lyon Nicholas Wiesenberg RD D'Arrigo |
| |
Institution: | aDepartment of Geology, The College of Wooster, 1189 Beall Ave, Wooster, OH, 44691, USA;bCold Regions Research and Engineering Lab (CRREL), 72 Lyme Road, Hanover, NH 03755, USA;cDepartment of Geology, Utah State University, 1400 Old Main Hill Logan, UT 84322, USA;d1276 Scenic Heights Drive, Wooster, OH 44691, USA;eTree Ring Lab, Lamont-Doherty Earth Observatory, Palisades, NY 10964, USA |
| |
Abstract: | Two interstadial tree ring-width chronologies from Geikie Inlet, Glacier Bay Southeast, Alaska were built from 40 logs. One of these chronologies has been calendar dated to AD 224–999 (775 yr) crossdating with a living ring-width chronology from Prince William Sound, Alaska. Trees in this chronology were likely killed through inundation by sediments and meltwater from the advancing Geikie Glacier and its tributaries ca. AD 850. The earlier tree-ring chronology spans 545 yr and is a floating ring-width series tied to radiocarbon ages of about 3000 cal yr BP. This tree-ring work indicates two intervals of glacial expansion by the Geikie Glacier system toward the main trunk glacier in Glacier Bay between 3400 and 3000 cal yr BP and again about AD 850. The timing of both expansions is consistent with patterns of ice advance at tidewater glaciers in other parts of Alaska and British Columbia about the same time, and with a relative sea-level history from just outside Glacier Bay in Icy Strait. This emerging tree-ring dated history builds on previous radiocarbon-based glacial histories and is the first study to use tree-ring dating to assign calendar dates to glacial activity for Glacier Bay. |
| |
Keywords: | Glacier Bay Alaska Tree rings Dendrochronology Glacial history First millennium AD |
本文献已被 ScienceDirect 等数据库收录! |
|