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We propose that most fault slip rate variability across a range of time and spatial scales is due to intrinsic faulting processes, rather than extrinsic changes in surface loads or stress boundary conditions. This hypothesis is tested by comparing very high geologic resolution slip histories of blind thrust faults from three transects in the Northern Apennines, Italy. We investigated whether these slip histories document synchronous, or independent, behavior of the disconnected, blind thrust faults that core mountain front anticlines bordering the Po foreland. The slip history for these thrusts is reconstructed by applying forward structural modeling to deformed growth strata and fluvial terraces preserved on the limbs of the growing anticlines. We present a new age model using magnetostratigraphy and cyclostratigraphy for a section of growth strata exposed in the Panaro River and supplement this with age models for two other published transects. The blind thrust fault at each transect exhibits variable slip behavior over the past 3 Myr, but for most of that time the variability was both asynchronous and independent of boundary condition changes, such as Plio-Pleistocene sediment accumulation variability. However, a major deceleration in slip rates at all three locations is temporally coincident with the overfilling of the Po foreland beginning in the early Pleistocene. We attribute the deceleration to a switch from shortening on shallowly detached thrusts to shortening on a crustal-scale basement-involved fault. This switch has implications for the time and spatial scales at which extrinsic boundary conditions may contribute to deformation variability.

Lithostratigraphic, magnetostratigraphic and rock-magnetic cyclostratigraphic data were combined to create a high-resolution age model for 342 m of Late Pliocene-Middle Pleistocene marine deposits exposed in the Stirone River, northern Italy. Magnetostratigraphic analysis of 74 oriented samples at 21 stratigraphic horizons recognized five polarity zones between c. 3.0 and 1.0 Ma. Unoriented samples were collected every metre between 0 and 311 m and low-field magnetic susceptibility (x) was measured for cyclostratigraphic analysis. The x data series was tied to absolute time using the magnetostratigraphy and subjected to multi-taper method spectral analysis. The resultant power spectra revealed significant frequency peaks that are aligned with eccentricity, obliquity and precession Milankovitch orbital cycles. The x data, correlated to the 41 ka obliquity and the 23 ka/19 ka precession cycles and anchored to a well-established biostratigraphic horizon, were used to create a high-resolution age model for the Stirone section between 2.99 and 1.81 Ma, where stratigraphic positions of magnetic reversals were previously poorly defined. This cyclostratigraphic age model reveals that the length of an important depositional hiatus at the base of the C2An.1n subchron is 200 ka shorter than previously determined. We link the precession-aligned variability in x to global mid-latitude, insolation-induced variability in runoff and ocean circulation.

Digital technology advances are rapidly altering the landscape of geoscience teaching and practice. Although geoscience has readily embraced new digital technologies in the past, the simultaneous emergence of innovations like open online courses and machine learning toolkits has greatly steepened the learning curve for geoscientists of all experience levels. Here, we discuss how these technologies are affecting the jobs of geoscience teachers and practitioners by highlighting a few technology-related trends in these areas. We also note the potential challenges of this new technological environment. A holistic view of digital technology trends can help geoscientists position themselves for success in a future where technological advancements will presumably continue to occur at an even more rapid pace.

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