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Subaerial rise of Earth's first continents took place 3.3–3.2 Ga years ago. This had significant influence on the ocean, atmosphere, and biosphere. Two important sedimentological consequences of continental emersion were (1) development of terrestrial (alluvial fan–fluvial–aeolian) depositional systems and (2) formation of shallow-marine sedimentary basins near the continental margin. Late Paleoarchean–Neoarchean terrestrial deposits, including development of an extensive paleosol around 3.2 Ga, and Meso–Neoarchean shallow-marine deposits have been reported from the Singhbhum Craton, eastern India from several localities. However, lateral and vertical changes in sedimentary facies associations and stratigraphic correlation between these terrestrial to shallow-marine sedimentary deposits have not yet been investigated. In this paper, we have reviewed the sedimentological characteristics of Late Paleoarchean to Neoarchean (3.2–2.8 Ga) stratigraphic successions of the Singhbhum Craton and have discussed sea level change and mode of stratigraphic sequence building. Our analysis shows that Singhbhum granitoid complex was emplaced around 3.3 Ga in an intracontinental setting, resulting in high continental freeboard conditions that triggered terrestrial (alluvial fan–braided fluvial) sedimentation (Dhosrapahar Formation). Continental sedimentation continued until ca. 3.0 Ga. In the eastern (Simlipal Group), western (Birtola Formation), and southwestern (the Mankarchua, Mahagiri, and Keonjhar formations) parts, shallow-marine sedimentation occurred after 3.0 Ga as a result of transgression. However, in the northern part (Dhanjori Formation), continental sedimentation prevailed throughout the Archean. These Late Paleoarchean to Neoarchean terrestrial and near-coastal successions of Singhbhum Craton should be the prime targets for intense geobiological research. [ABSTRACT FROM AUTHOR]

The Cretaceous Western Interior Basin reflects the interplay between the North American craton and allochthonous terranes to the west. We divide the basinal stratigraphy into three successions, Aptian–Albian, Cenomanian–Turonian, and Santonian–Maastrichtian, each related to periods of deformation in the adjacent fold-thrust belt. Here we focus on the Cenomanian–Turonian succession, where progressive west to east uplift and fluvial incision of older Aptian–Albian sedimentary rocks (Cedar Mtn–San Pitch–Thermopolis–Skull Creek–Mannville) are interpreted as a migrating forebulge. Uplift was underway at 103 Ma in the west (Paddy–Blackleaf–Muddy sandstones) and propagated eastward throughout the trough by 99.5 Ma (Viking–Bow Island–Newcastle sandstones). The incised fluvial valleys were subsequently filled by swampy and shallow marine facies, then overlain by dark, marine Neogastroplites-bearing shale and associated bentonites of the 100–97.5 Ma Shell Creek–Mowry–Slater River–Goodrich–Shaftesbury–Westgate shales. The shales are characterized by a distinctive condensed horizon with abundant fish scales, teeth, and bones. They are interpreted as outer-trench slope deposits, with the overlying anoxic horizon representing a starved isochronous unit formed atop the slope deposits. The starved horizon is overlain by prodeltaic muddy clinoforms of easterly migrating clastic wedges (Trevor–Dunvegan–Frontier–Cintura–Mexcala) that can be traced 800 km atop the fish-scale hash and contain hinterland-derived 99–90 Ma detrital zircons. Although the Western Interior Basin has long been considered a retro-arc trough, the overall succession instead suggests that the Cretaceous–Turonian part represents a collisional foredeep created during the ∼100 Ma collision between the arc-bearing Peninsular Ranges composite terrane and North America. The accretion brought tyrannosaurids, pachycephalosaurs, snakes, and marsupials to North America. [ABSTRACT FROM AUTHOR]