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The Fraser River Delta (FRD) is a large sedimentary system and home to Metro Vancouver, situated within the unceded territories of several First Nations. This review provides an overview of the geological evolution of the FRD, connecting hydrodynamic processes with sedimentary deposits across its diverse environments, from the river to the delta slope. The study emphasizes the implications of sedimentation and delta evolution for natural hazards and coastal/delta management, pinpointing knowledge gaps. Comprising four main zones—river, delta plain, tidal flats, and delta slope—the FRD is subject to several natural hazards, including subsidence, flooding, earthquakes, liquefaction, and tsunamis. The delta plain, bordering the Fraser River's distributary channels, hosts tidal marshes and flats, including both active and abandoned areas. Active tidal flats like Roberts Bank and Sturgeon Bank receive sediment directly from the Fraser River, while abandoned tidal flats, like those at Boundary Bay and Mud Bay, no longer receive sediment. The tidal flats transition into the delta slope, characterized by sand in the south and mud in the north of the Main Channel. The FRD's susceptibility to hazards necessitates protective measures, with approximately 250 km of dykes shielding the delta plain from river floods and storm surges. Subsidence amplifies the impact of rising sea levels. Earthquakes in the region can induce tsunamis, submarine slope failures, and liquefaction of delta sediments, emphasizing the importance of incorporating sedimentation patterns and delta evolution into management strategies for sustainable urban development, habitat restoration, and coastal defence initiatives. [ABSTRACT FROM AUTHOR]

Sedimentological and ichnological descriptions of fluvio‐tidal translating point bars are rare, and complex physico‐chemical processes make highly detailed but concise facies descriptions challenging. Herein, mesofacies are defined to describe and interpret three ancient translating point bars from the Lower Cretaceous McMurray Formation, Alberta, Canada. Twenty‐three mesofacies are defined, based on their recurring sedimentological and ichnological characteristics. These mesofacies form the building blocks of beds and bedsets that make up three depositional facies. Facies 1 reflects sand dune migration at the channel base, which grades into inclined heterolithic stratification of Facies 2 and 3. Facies 2 occurs in the centre and seaward portions of the translating point bars and records tide‐dominated deposition of sand and muddy sand during periods of reduced river discharge. Ichnological suites and bioturbation intensities in these beds reflect persistent but variable brackish‐water conditions, fluctuating deposition rates and the deposition of mud. Mud beds are derived from flows with high suspended‐sediment concentrations. Tidally derived mud beds are typically bioturbated with trace fossil suites indicative of slow deposition rates and brackish‐water conditions. Mud deposited during elevated river discharge is burrowed after the dewatering of the bed. Facies 3 occurs at the landward apex of the translating point bar and is marked by sand‐rich and mud‐rich dune deposits with abundant soft‐sediment deformation, indicative of elevated flow velocities and deposition rates. Bioturbation is rare and sporadically distributed owing to unstable substrates. The distribution of the facies reflect the hydrodynamic variations that occurred vertically and laterally across the bar in response to temporal variations in fluvial and tidal flow interaction, as recorded by their mesofacies. The detailed facies analysis strongly suggests that deposition of the three McMurray Formation translating point bars occurred in proximity to the turbidity maximum zone of a fluvio‐tidal channel system. [ABSTRACT FROM AUTHOR]

The Cretaceous lower Nanaimo Group in the Georgia Basin, Canada comprises multiple depositional phases with distinct depocentres that accumulated in a tectonically active forearc basin setting. Basal coarse-clastic strata are preserved in paleotopographic depressions and grade upwards into coal-bearing coastal plains and shallow-marine deposits. Coal-bearing and shallow-marine strata grade laterally into and are overlain by, regionally extensive mudstones and turbidites deposited in deep water. A glauconitic sandstone bed within the deep-water strata is interpreted as a condensed section and underlies a major disconformity that developed during a pause in the deposition of the lower Nanaimo Group. A second major coarse-clastic succession occurs hundreds of metres above the glauconite bed in the central Georgia Basin and comprises conglomerate, sandstone, mudstone and coal deposited in continental depositional environments. The shift in sedimentation from the northern Georgia Basin to the central Georgia Basin is interpreted to record the emergence of an island (Nanoose Uplift) in the central Georgia Basin that acted as a major sediment source to the adjacent depocentres. The stratigraphic break between the coal-bearing coarse-clastic strata in the northern Georgia Basin and the significantly younger coal-bearing coarse-clastic strata in the central Georgia Basin indicates that the lower Nanaimo Group was deposited in distinct depocentres. Between the older, coarse-clastic strata in the north and younger, coarse-clastic strata in the central Georgia Basin, we hypothesize that a major deepwater canyon system (Qualicum Canyon) existed and transferred sediment from the semi-restricted Georgia Basin to the Pacific Ocean to the west. Development of the Qualicum Canyon and exposure of the Nanoose Uplift during deposition of the younger, central coarse-clastic strata suggests that syntectonic activity drove basin uplift and erosion and this occurred throughout the deposition of the lower Nanaimo Group. [ABSTRACT FROM AUTHOR]

The Taiwan Western Foreland Basin is thought traditionally to have received sediment mainly from Eurasia until the late Pliocene–early Pleistocene, after which time, the Taiwan orogen became the dominant source. However, a combination of clay mineralogy, δ13Corg and C/N of organic matter, and mass‐specific magnetic susceptibility of late Miocene to early Pliocene strata of the Kueichulin Formation indicate that onset of major sediment contributions from Taiwan occurred much earlier, and correlates closely to the uplift and initial emergence of the Taiwan orogen. Clay mineralogy shows an upsection increase in illite and illite crystallinity, and a decrease in chlorite and kaolinite after the late Miocene, and this is attributed to rapid erosion of the Taiwan orogen. Results from δ13Corg and C/N analyses show that organic material in the Kueichulin Formation changed from dominantly marine to dominantly terrestrial in the early Pliocene, and this is linked to the delivery of large quantities of terrestrial organic material from the Taiwan orogen to the adjacent Taiwan Strait. Magnetic susceptibility also decreases significantly during the early Pliocene, resulting from dilution of magnetic minerals through the influx of non‐magnetic minerals delivered from the Taiwan orogenic belt. The establishment of the growing Taiwan orogen as a major sediment source to the Western Foreland Basin occurred at the Miocene–Pliocene transition, about two million years earlier than previously recognized. [ABSTRACT FROM AUTHOR]