Coarse Devonian terrestrial sediments were deposited in six distinct basins preserved along the western coast of Norway 100-200 km north of Bergen. The brown- to red-colored alluvial conglomerate, breccia, and sandstone, loosely termed "Old Red Sandstone," were derived from nearby surrounding source areas. The basins are similar tectonically and sedimentologically to the Triassic Newark basins, in that they were formed after a major geosynclinal orogeny (Caledonian), consist of thick redbed sequences with plant and fish remains, are bounded by normal faults with apparently large displacements, contain mafic intrusives and extrusives, and have been subjected to post-depositional folding, faulting, and uplift. However, the Norwegian analogues are more limited in area and in lithologic variety.

The Solund and Buelandet-Vaerlandet Norwegian Devonian basins contain well-exposed sedimentary structures, textures, and fabrics. About 5,000 m of coarse conglomerate, with scattered, interbedded lens-shaped bodies of sandstone, crops out in the Solund basin. The conglomerate represents a broad coalesced alluvial fan complex deposited into an eastwest-trending half-graben (40 × 20 km). The southerly source area, composed primarily of Caledonian igneous and metamorphic rocks, was a rapidly eroding highland dissected by youthful streams transporting coarse debris northward to the fans. Uniform orientation of sedimentary structures and fabric throughout the basin indicates a relatively steep northward-sloping depositional gradient.

The Solund conglomerate beds are generally massive, structureless bodies, with a prominent, anisotropic imbricated fabric. Flat stratification is the most common feature of sandstone lenses within conglomerate beds; primary current lineation and cobble-boulder trains are typically associated. Cross-strata are either large-scale singular plunging troughs, festoon troughs, or planar or tabular small-scale types. Ripple-drift bedding is prominent locally, as are asymmetrical current ripple markings and sand waves. Erosive features include channel scours and preserved undercut banks of stream channels. Evidence of rockslide deposition is found locally. Fining-upward cycles of sandstone-conglomerate are characteristic of many of the sandstone lenses. The stratigraphic evidence suggests dep sition in braided stream channels, primarily under conditions of the upper-flow regime, on a humid-temperate coalescing alluvial fan complex.

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