This article argues that Internet censorship is more fragile than is generally supposed and is, in fact, vulnerable to abrupt collapse. The volume and rapidity of online communication renders perfect policing of the Internet technologically impossible. Authoritarian governments are thus forced to rely on Internet users to police themselves in the form of self-censorship. This strategy has proven largely successful—legal ambiguity regarding what constitutes impermissible speech fosters norms of self-censorship. This reliance on self-censorship, however, renders these censorial systems susceptible to shocks. We set out a model that explains sudden breakdowns in Internet censorship that we term “cyberspeech cascades.” A cyberspeech cascade occurs when small expressions of online dissent produce large shifts in public perception regarding the acceptable limits of online expression that are, in fact, inaccurate. Online bandwagons of progressively more brazen speech proliferate into large-scale torrents of uncensored expression, triggering the temporary collapse of self-censorship norms online.

Sand-rich turbidite systems in structurally complex, fault-bounded deep-water basins often form prolific hydrocarbon reservoirs. Outcrop studies of ancient examples of these turbidite systems provide information on architecture, depositional controls, and sandstone distribution. Outcrops of the Miocene upper Modelo Formation in eastern Ventura basin, California, are interpreted as a longitudinal transect through a fault-controlled deep-water depositional system, from proximal structural terraces, through a submarine canyon, to the basin floor and toward the basin margin. This study area is divided into three regions based on geographic location, geologic features, and stratigraphic character and architectures. Region 1, interpreted as the feeder system, contains syndepositionally active normal faults (e.g., Devil Canyon fault) near the proximal basin margin; these faults are associated with abrupt changes in depositional environments, lithofacies associations, paleobathymetry, and stratigraphic thickness. An interpreted submarine canyon, with a low net-sandstone content infill, was an area of bypass. Isopach maps reveal that gross thickness is greatest near the canyon mouth. In Region 2, interpreted as the proximal basin floor, a fairway located immediately basinward of the canyon has the highest sandstone content in the basin. In Region 3, interpreted as the medial–distal basin floor, gradual changes in proportions of lithofacies associations are the result of subtle variations in the gradient of the basin floor near the distal basin margin, as interpreted from an isopach map of the upper Modelo Formation. In this area, channel complexes comprising structureless, amalgamated sandstone overlie thin-to medium-bedded, poorly sorted, clay-rich sandstones deposited at lobe fringes. This upward architectural pattern is interpreted as a product of an outwardly expanding depocenter through time.

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for their insightful comments. I am indebted to Mark Grainger, Rhonda Schwartz, and David Haberman for their invaluable research assistance. This work would not be possible without the support of my wonderful wife and our two precious girls.