Stone Stripes, Montana
creep, solifluction, alpine
Fractures near head of landslide (vertical)
mass wasting, gravity, erosion, crack, headwall
Antecedent River, Montana
superposed,
Fractured Granitic rock
granite, mechanical, physical weathering
Talus on Mountain Slope
alpine, scree,
Hogbacks
differential erosion, ridges, Block Mountain, BMMT
Soil Profile in grassland
chemical weathering, pedogenesis
Mudcracks and Ripple Marks
Mudcracks (left) and ripple marks (right) in rock of the Belt Supergroup. The mudcrack is about 20cm across; the ripple marks are roughly 1m across. (Image ID# belt-sedsrs-pic)
Cloudy Peaks
Bright mountain peaks guard a quiet river. (Image ID# 140720-6)
Proterozoic stromatolite (vertical)
limestone, laminations, algal mat, Precambrian, stromatalites
Marine Transgression diagram
If you look at Time 1, you can see a coastline in cross-section, with sand being deposited closest to shore, mud a little farther out, and eventually carbonate material even farther out. As sea levels rise in Time 2, the sites of deposition for these materials migrates landward, putting mud deposition on top the earlier sand deposition and so on. In time 3, the sequence moves even farther landward, resulting in carbonate over mud over sand. If these materials become preserved and turned into rock, they form the sequence sandstone overlain by shale overlain by limestone – just what we see on top the Great Unconformity. (Image ID# transgression)