

Clastic Dikes at Metalline Falls, WA
Olaf P. Jenkins took these photos in 1924 near Metalline Falls, WA. They show Pleistocene-age clastic dikes intruding rippled glaciofluvial/glaciolacustrine sediments of Glacial Lake Pend Oreille 80km NW of Priest River, ID. The lake used to occupy the southern end of the Purcell Trench during the last Ice Age. They are not the sheeted dikes found throughout the Channeled Scabland, but they are unusual and beautifully photographed here. Photo caption: "Metaline District, diff


Pleistocene(?) Alluvial Stratigraphy - Lind Coulee, WA
Non-flood sediments of Pleistocene age are well exposed along Crab Creek in Lind Coulee east of O'Sullivan Dam. Very little has been written about Pleistocene alluvium in the Channeled Scabland. A few cryptic comments by mapping geologists working in the area 50 years ago is about all. West and Shaffer (1988) note the odd Pleistocene alluvium and loess encounteered during the paleoseismic trenching work, but provide few details. The valley bottom deposits pictured below are p


Tetons Drive
Photos from a drive around Teton Valley in November 2021. Mormon Row Jackson Hole Mountain Resort from Spring Creek Snake River from Clark Hill Gros Ventre Valley The Grand, Mount Owen, Teewinot Rendezvous Peak Jackson Hole Mountain Resort Tram building at JHMR Albright Peak, Static Peak, Buck Mountain, Veiled Peak, Mount Wister Runs open in November Blacktail Butte Gros Ventre Valley Mount Moran Gros Ventre Valley South Teton, Nez Perce Peak, Middle Teton, The Grand, Mount O


Structureless Sandstone Beds - White Bluffs, WA
Structureless sand is fairly unusual in the geologic record. Sandy sediment deposited by flowing water typically preserves bedforms. Bedform geometry contains tons of information geologists use to interpret flow conditions and geologic setting when the sediment was deposited. Massive sands come in two flavors: Sheet-like deposits (braided fluvial) or channel-like deposits (braided fluvial, fluvial lacustrine, marginal marine, glaciofluvial) and are interpreted as either a.) l


Diatomite Lake Invaded by Molten Lava - Frenchman Hills, WA
A pillow-palagonite complex forms when molten lava invades a body of water, whether its the ocean, a river, or a lake. Pillows are the quenched blobs of lava. Palagonite is the loose, rusty-looking mess that surrounds pillows. Palagonite is composed of basaltic glass, shards of basalt rock, and maybe even some cooked sediment. Its the alteration product of 1100 degC lava coming into contact with 25 degC water and flashing to steam. The stuff was loose and ravelly when it form


Old Maid Coulee Site Geology - Connell, WA
The Old Maid Coulee site, located near Connell, WA, contains convincing evidence of "pre-late Wisconsin" flooding. Geologists distinguish deposits from the more voluminous and better-studied Missoula floods (18-14 ka), which are "late Wisconsin" age, from those left by older floods, we call "pre-late Wisconsin" floods or sometimes "ancient floods". The older flood record is thinner, somewhat ambiguous, and contains conspicuous calcic paleosols (caliche, calcrete), which attes