Alpine glacial erosion, through overdeepening of valleys, may lead to structural collapse of the valley sides and mountain crest along small normal faults. Such features, known as sackungen, are described from crystalline rocks of the Alps and Rocky Mountains. Sackungen are reported herein for the first time from sedimentary bedrock of the Culebra Range of the Sangre de Cristo Mountains in south-central Colorado. The examples include small and large valley-side ridges and a double-crested mountain ridge. In all cases, the sackungen trend parallel to valleys sides or ridge crests above the limit of glaciation. Sackung deformation may involve both brittle and ductile mass movements of bedrock, which were probably aided by ice in subsurface joints. Seismic activity may have contributed to formation of sackungen in the Culebra Range. Sackungen are examples of glaciotectonic features created in hard bedrock under the impact of glaciation.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 111 • No. 1