The outcrop of the Toby Conglomerate extends sinuously from southeastern British Columbia to northeastern Washington. It constitutes the basal part of the Windermere System (Upper Proterozoic), unconformably overlies the beveled Upper Purcell System, and conformably underlies either volcanic rocks or clastic Windermere sedimentary rocks of the Horsethief Creek Group and Monk Formation. The Toby Conglomerate consists chiefly of diamictite, which is complexly interstratified with conglomerates, sandstones, and argillites, the latter two containing dispersed megaclasts. Toby Conglomerate thickness ranges markedly from a few to nearly 2000 m. There is a dearth of tractive-current features within Toby sedimentary rocks. The presence of overlying pillow lavas and laminated argillites, turbidites, and grain flow deposits suggest that the basal Windermere System is of sub-aqueous origin. Paleogeographic reconstruction indicates deposition in the sea west of the orogenic landmass, Montania, peninsular to the Canadian Shield.Texture, composition, stratigraphie associations of Toby sedimentary rocks, and a lack of consistent regional variation suggest that the Toby Conglomerate was deposited by glacial marine sedimentation. Montania was overridden by ice traveling westward from the shield prior to Toby deposition. The basal Horsethief Creek Group and Monk Formation were produced largely by postglacial mass flow of slumped tills and deltaic deposits. This represents a new interpretation of the genesis of the Toby Conglomerate, one which accords with worldwide evidences of a Late Precambrian ice age.

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An olistostrome and bounding turbidites are exposed within the late Mesozoic Franciscan Complex along the Crescent City (California) coastline. Facies grade in character from Mutti & Ricci Lucchi (1978) mixed facies B, C and D, to F (the olistostrome), to mixed A, B and E, progressing upwards within the Franciscan stratigraphic section. The facies F unit outcrop is up to 600 m thick and extends 12 km along strike. It consists of oblate to tabular blocks, up to 200 m in maximum dimension, of greenstone, tonalite, radiolarian chert, limestone, phyllite and greywacke dispersed in a scaly argillite matrix. The olistostromal origin of the unit is indicated by depositional contacts with bounding turbidites, by the presence of abundant recycled sedimentary clasts within the unit, and by the presence of sedimentary breccias and associated dismembered, slump‐folded turbidites both within the olistostrome and among subjacent turbidites. Sandstones are chiefly feldspathic litharenites that were very likely derived from the partially dissected, late Mesozoic Sierran‐Klamath magmatic are. Franciscan rocks record an early pervasive, layer‐parallel flattening strain in such features as extensional faults, necking and pinch‐and‐swell structures. Several scales of extensional faulting account for the juxtaposition of turbidites of different facies and/or with varying degrees of stratal disruption, the formation of sandstone lozenges, and the formation of scaly foliation in the olistostrome matrix. The latter resulted from the juxtaposition of lenticles with varying concentrations of silt and clay. These were ultimately derived from the finer divisions of turbidite beds that were incorporated into the olistostrome. The presence of gradational contacts between some sandstone olistoliths and the olistostrome matrix, and of sandstone dykes that intrude fractures and associated drag‐folded turbidite beds indicate that Franciscan sediments were not lithified during their early deformation. These sediments were deposited in either a trench or trench slope basin, and were first deformed either by gravity collapse of the trench slope cover or, less likely, by vertical loading beneath the toe of the accretionary wedge. They later were folded during internal shortening of the growing Franciscan accretionary prism.

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