The Fahliyan Formation (Lower Cretaceous, Berriasian–Hauterivian) in the Zagros Basin of southwest Iran represents one of the most significant shallow-marine carbonate successions along the northeastern margin of the Arabian Plate. Detailed microfacies analysis of two subsurface stratigraphic wells (Aghar-19 and Dey-2) reveals a spectrum of 12 microfacies ranging from tidal-flat to open-marine settings. These microfacies include dolo-wackestone, stromatolite boundstone, algal intraclast wackestone foraminifer bioclast wackestone, Trocholina bioclast wackestone, Fine ooidal peloidal grainstone, coarse ooidal peloidal grainstone, intraclast ooidal grainstone, coral boundstone, bioclast packstone, bioclast wackestone, and sponge spicule bioclast wackestone, reflecting deposition across supratidal, tidal flat, lagoon, reef, fore-shoal, and slope environments. Vertical distribution of the facies demonstrates variations in paleobathymetry between the studied sections, with higher proportions of skeletal grains in the upper Aghar-19 well (47%) and mid Dey-2 well (50%). The abundance of skeletal components, particularly corals, benthic foraminifera, and calcareous algae, indicates favorable paleoecological conditions with sufficient light, nutrients, and normal salinity during the Early Cretaceous. These findings highlight the influence of the Late Cimmerian tectonic movements and basement faults on carbonate platform development and depositional architecture. Overall, the integrated microfacies and stratigraphic data provide new insights into the paleogeography and paleobathymetry of the Early Cretaceous Zagros Basin and underscore the significance of the Fahliyan Formation as a potential hydrocarbon reservoir.

This study revises the lithostratigraphic framework of the Upper Devonian interval traditionally assigned to the Greenland Gap Group across the central Appalachian Valley and Ridge Province. The work aims to modernize and standardize lithostratigraphic nomenclature, establish a new reference section and demonstrate how the revised stratigraphy improves edgematching of 1:24,000 scale geologic maps and supports compilation mapping at scales of 1:100,000 and larger. The revision eliminates the names Greenland Gap Group, Scherr Formation and the Minnehaha Springs Member of the Scherr Formation; reassigns all strata previously designated as Scherr Formation by Dennison (1970) to the upper Brallier Formation; and abandons the basal Mallow Member of the Foreknobs Formation, placing its strata within the upper Brallier as originally defined by Butts (1918). The contact between the Brallier and Foreknobs formations is placed at the base of the first mappable, ridge-forming package of fine- to coarse-grained, cross-bedded, sandstone beds, often containing rounded quartz pebbles with minor interbeds of shale and siltstone. This contact may be gradational in places but, even in absence of good exposure, can usually be distinguished topographically in recently produced lidar-derived imagery as having elevated relief due to the presence of more resistant, compositionally mature coarsegrained sandstone-rich strata. Applying this criterion for mapping the contact between the Brallier and Foreknobs formations has resulted in reconciliation of mismatches of geologic contacts along several 7.5-minute quadrangle boundaries in the states of Virginia,West Virginia,Maryland and Pennsylvania. A new reference section at Baker, West Virginia showcases the contacts between the Harrell Shale, Brallier Formation, Foreknobs Formation and Hampshire Formation. A digital outcrop model of the reference section is provided for future preservation.

The Cretaceous Farrokhi Formation is located in the Khur area of central Iran and yielded a reasonably well-preserved rich planktonic foraminiferal assemblage. This formation consists of 154 m of fossiliferous marl and limestone. The lower and upper bounding surfaces of the Farrokhi Formation are unconformable with the underlying Haftoman Formation and the overlying Chupanan Formation. In this research, 46 planktonic foraminiferal species belonging to 19 genera were identified and resulted in recognition of the following three biozones (from base to top); the Globotruncana aegyptiaca Interval Zone (IZ), the Gansserina gansseri IZ, and the Contusotruncana contusa IZ. This biozonal framework places deposition of the Farrokhi Formation during the late Campanian to early Maastrichtian. Biostratigraphic comparison between the samples for this research and data from three other studied sections within the Farrokhi Formation indicates that the basal and upper boundaries of the formation are time-transgressive and migrate chronologically from north to southeast. Since the first occurrences of Pseudoguembelina palpebra and Rugoglobigerina pennyi mark the latest Campanian worldwide, we approximate the Campanian/Maastrichtian boundary based on the FOs of Trinitella scotti and Rugoglobigerina hexacamerata, and identify the basal Maastrichtian by the last occurrence of Laeviella bollii.

The upper Albian exposed near the Imbrication Zone of northern Tunisia is composed of a pelagic sequence that includes organic-rich beds. High-resolution biostratigraphy based on planktic foraminiferal bioevents across marker beds (i.e., organic-rich beds), allows revision of the lithostratigraphic subdivision and zonal scheme in comparison with late Albian time equivalents recorded in the northern Tethyan margins. In the present study, we proposed a new subdivision of the upper Albian lithostratigraphic section that now includes the Mellegue horizon as an equivalent of theAmadeus Segment rhythmic marl/limestone interval (central Italy). Three studied sections are subdivided into five biozones with the abundance and morphological trends of planktic foraminifera and inferred paleoenvironments: 1) The Biticinella breggiensis Total Range Zone is characterized by the appearance of ticinellids with pinched chambers (i,e., Ticinella praeticinensis) and is recorded a few meters above the first occurrence of Biticinella breggiensis. Agradual increase of trochospiral thick-walled (B. breggiensis, T. roberti, T. raynaudi) and Globigerinelloides taxa, reflecting mesotrophic conditions. 2) The Pseudothalmanninella subticinensis Interval Zone includes the first appearance of keeled forms (Ps.subticinensis), associated with abundant ticinellids with flattened chambers (B.breggiensis, T. roberti) below the base of the organic-rich Mellegue horizon, indicating an oligotrophic environment. 3) The Pseudothalmanninella ticinensis Interval Zone. The continuous occurrence of T. primula and the scarcity of Globigerinelloides throughout the lower part of this zone indicates an oligotrophic to weakly mesotrophic environment. The occurrences of radiolarian-rich horizons and abundant forms with elongated chambers (T. raynaudi) in the lower part of this zone indicate an abrupt shift to enhanced eutrophic and dysaerobic conditions. 4) The Thalmanninella appenninica Zone, which shows a decrease in abundance preceding the extinction of ticinellids, and a gradually increasing number of specialized keeled forms (i.e., Th. appenninica), indicates oligotrophic conditions. 5) The Planomalina buxtorfi Total Range Zone is characterized in its lower part by an increasing abundance of clavate forms with radially elongated chambers (i.e., Clavihedbergella) above the organic-rich bed of the Mouelha Member, indicating low-oxygen, oligotrophic to mesotrophic conditions.

The North American Stratigraphic Code ("the Code") addresses the naming of formal geologic units from a scientific perspective. Guidelines based on scientific rationale are provided for assigning and revising unit names. However, whereas some scientific codes and guidelines now address the problem of offensive or inappropriate names, the Code at present has no means of addressing such matters. This omission presents a problem because most categories of formal units covered by the Code are named after geographic features, and some units have thus inherited culturally offensive or inappropriate names. The naming of geographic features (toponymy) also has reflected the historic suppression of Indigenous languages in North America. To address the first issue, additions and changes to the Code are proposed around the use of culturally offensive or inappropriate names: to explicitly counsel against their use; to provide a simplified process to rename scientifically valid units; and to invalidate nomenclatural stability as a justification for retaining such unit names. To address the second issue, additions to the Code are proposed that recognize maps produced by Indigenous governments or organizations as sources of geographic names, and that encourage the respectful use of Indigenous place names.

We document the stratigraphy, lithofacies and depositional environment of the lower Eocene-lower Oligocene Nisai Group, based on petrographic and micropaleontological analysis, and field observations.We rename the whole sedimentary succession as the Nisai Group and divide it into three formations, from bottom to top; Jabrai, Torkhezhe Tsah and Nisai formations. The Jabrai Formation comprises a thick succession of olive gray mudstone and shales with subordinate sandstone, limestone and quartzose conglomerate, interpreted as deltaic and littoral deposits. The Torkhezhe Tsah Formation comprises calciturbidites in its lower part and periplatform oozes and basinal shales in upper part. The shallow-marine carbonate material of calciturbidites possibly derived from a lost platform which was a narrow delta-top-platform developed over deltaic sediments of the Jabrai Formation. The uppermost unit, the Nisai Formation, comprises thick bedded limestone with subordinate shale and nodular reefoid limestone, and shows a shallowing-up succession overlying the slope and basinal deposits of the Torkhezhe Tsah Formation. The presence of Cr-rich spinels in sandstone of the Jabrai Formation, ultramafic-mafic and quartzite lithoclasts in calciturbidite beds as well as paleocurrent data, suggest that siliciclastic sediments of the Nisai Group derived from the Zhob Valley Ophiolites. Moreover, the presence of quartz, igneous and metamorphic extraclasts, and dolomitic horizons within calciturbidite beds, indicate deposition of these calciturbidites in response to lowering of sea level.We propose that emplacement of Zhob Valley Ophiolites served as a drainage divide and supplied deltaic sediments to the Jabrai Formation to its north and the Ghazij Group to the south.

The timing of the facies transition from the Decatur Limestone to the overlying Rockhouse Limestone Member of the Ross Formation in western Tennessee was evaluated using conodont faunas and the delta 13C carb curve. The facies transition corresponds to conodont extinctions associated with the Klonk Oceanic Event and with the Klonk isotopic excursion, which span the Silurian-Devonian boundary interval. The interpreted position of the Silurian-Devonian boundary is placed near the top of the Decatur, above the conodont extinction level and in the ascending limb of the isotopic excursion. The lowest occurrences of the Devonian species Caudicriodus murphyi and C. anitae are slightly higher, at the top of the Decatur, and both species characterize the Rockhouse Limestone Member. The conodont succession across the Silurian-Devonian boundary is like that reported from sections in West Texas and Oklahoma and represents a regional biological response to the Klonk Event in the southern part of the Appohimchi Subprovince of the Appalachian Province, one that is also represented by comparable changes in brachiopod and ostracode faunas. Correlation into the northern part of the Appohimchi Subprovince is best accomplished using the delta 13C carb curve. The western Tennessee conodont fauna includes two closely related species of Zieglerodina, Z. zellmeri and Z. planilingua, as well as distinctive forms of Pseudooneotodus.