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We present a detailed geologic study of the Thebes Formation at Gebel Gurnah in its locus typicus on the West Bank (opposite Luxor) of the Nile River in the Upper Nile Valley, Egypt. This is the first detailed measurement and lithologic description of the ∼340 m thick (predominantly) carbonate section. The Thebes Formation is divided into thirteen major lithic units (A to M). We interpret data on the lithologic succession and variations, whole rock/clay mineralogy, and macro/micropaleontology in terms of deposition on a shallow carbonate platform episodically influenced by continental runoff, and describe six depositional sequences that we place in the global framework of Lower Eocene (Ypresian) sequence stratigraphy. We note however significant incompatibilities between the Thebes depositional sequences and the global sequences. We emend the definition of the Thebes Formation by defining its top as corresponding to level 326 m at the top of Nodular Limestone ‘L’ (NLL), and assigning the overlying beds to the Minia Limestone Formation. New biostratigraphic data and revision of previous studies establish the direct assignment of the Thebes Formation to planktonic foraminiferal Zones E4/P6b (upper part), E5/P7 and (indirectly) Zone E6/P8, and (probably, indirectly) Zone E7a/”P9”, and to calcareous nannofossil Zone NP12 and lower Zone NP13 of the Lower Eocene (Ypresian) and provide a temporal framework spanning ∼ 2.8 Myr from

Examination of the holotype of Globorotalia barisanensis Le Roy, 1939, has revealed that this species from the Middle Miocene of central Sumatra is non-keeled, contradicting the synonymizing of G. barisanensis with Globorotalia fohsi. Because the type sample is untraceable, we examined the available type specimens (holotype and eight paratypes), notes and data presented by previous researchers, and material from the near-topotype locality of Paragloborotalia siakensis, to clarify Le Roy's concept of G. barisanensis. Our investigation has revealed that the Middle Miocene of central Sumatra contains two different groups of globorotaliids: the Globorotalia menardii group and the G. fohsi group, and that G. barisanensis belongs to the latter. The paratypes examined belong to Globorotalia peripheroacuta and to forms transitional between G. peripheroacuta and Globorotalia praefohsi. The holotype, as described by Le Roy, is included in G. peripheroacuta as well, despite the observation that it differs from the paratypes in the abnormally inflated final chamber. In retrospect, the specimen selected as the holotype was an unfortunate choice as it has long been misinterpreted and used to denominate the earliest representatives of the G. fohsi group (viz. G. fohsi barisanensis) until G. barisanensis was reinterpreted as a junior synonym of G. fohsi based on a flawed redrawing of a fully keeled holotype of G. barisanensis. We conclude that Le Roy's concept of G. barisanensis was broad and may have included G. fohsi and Globorotalia peripheroronda as well. Remarkably, after 67 years of misinterpretation since Bolli (1950), G. barisanensis appears to be a valid name and a senior synonym of G. peripheroacuta. However, we recommend that it will be more practical to conserve the latter name, which is well established in the literature.

The taxonomy and phylogeny of the planktonic foraminifera Fohsella lineage has been controversial for nearly 50 years, despite its widespread application in Middle Miocene stratigraphy. We have re-examined type specimens of this lineage together with specimens from a continuous deep-sea record (Ocean Drilling Program Site 806, Ontong Java Plateau, western equatorial Pacific Ocean) with an astronomic chronology. Landmark-based geometric morphometry is employed to visualize and quantify morphologic variation within this lineage. Combined morphologic and stratigraphic data help clarify the evolutionary occurrence of diagnostic traits that characterize two problematic taxa, F. praefohsi and F. “praefohsi”, resulting in a revised taxonomy and phylogeny of the lineage. We emphasize the importance of biometric studies of populations from continuous geologic records in establishing taxonomy and phylogeny of planktonic foraminifera. In the past, over-emphasis on the importance of type specimens as reference points in delineating various evolutionary stages of the Fohsella lineage has resulted in inaccurate phylogenetic reconstructions.

A World Heritage Site since 1979, the Theban Necropolis was built by the Pharaohs of the 18th to 20th Dynasties ( c. 1539 – 1075 BCE). A variety of pharaonic (and lesser nobles9) tombs, funerary temples and sanctuaries were located/excavated in the lower part of the c. 400 m high pyramidal El Qurn in a variety of lithofacies (predominantly marine limestones and shales). These monuments are located in regionally persistent structural entities as well as gravitational collapse structures (GCS) whose probable origin and timing are reviewed and updated here, based on information that was unavailable to us at the time of writing a complementary paper in 2008 (but only published in 2015). We review here the historical development of the Theban Necropolis in the framework of the geological and geomorphological landscape and the first geological map of the region prepared by our Working Group for the Theban International Geoarcheological Project (TIGA) in 2011. We conclude with a preferential prioritizing of the perceived short- and long-term threats to the preservation of the Theban Necropolis and its monuments: least vulnerable to destabilization are the Valley of the Kings, Valley of the Queens, Block of Sheik Abdel Qurnah – El Khokkah; more vulnerable are Deir El Medina, Qunet Mura9I and El Assasif; most vulnerable are the Village of the Workers, Deir El Bahari and the Valley of the Colors. Accordingly it will be necessary to devise geotechnical solutions to prevent the destruction of (at least) some of the monuments under consideration here.

Paleontological studies on the Upper Paleocene-Lower Eocene succession at Darb Gaga, southeastern Kharga Oasis, Western Desert, Egypt document the changes associated with the Paleocene-Eocene Thermal Maximum (PETM), such as 1) a radical alteration of the relative and absolute abundance of planktonic foraminifera; 2) a massive occurrence of the excursion planktonic foraminiferal taxa; 3) a widespread deposition of calcarenite yielding atypical (extremely high) faunal abundance associated with the younger phase of warming; and 4) a concentration of coprolites associated with the middle phase of warming. We also document the Lowest Occurrence (LO) of dimorphic larger benthic and excursion foraminifera during the earlier phase of warming at Darb Gaga, as recorded in Bed 1 of the Dababiya Quarry Member. The absence of these faunas in Bed 1 at Dababiya (the GSSP for the P/E Boundary) is likely to be due to both intense deficiency in dissolved oxygen and massive carbonate dissolution. Only remains (fish remains) of faunas that can tolerate the toxicity produced by low oxygen conditions are found in the stratigraphic record of this (oldest) phase at Dababiya. The Dababiya Quarry Member (DQM) at Darb Gaga reflects the unfolding of the sedimentary and biotic changes associated with the PETM global warming at, and following, the Paleocene/Eocene boundary on the southern Tethys platform. The changes began with a rapid increase in bottom and “intermediate” water temperature. The temperature increase was accompanied by removal of oxygen during the early and middle stages of warming. This led to the absence of both subbotinids and calcareous benthic foraminifera in the early and second coprolite-bearing phases (Beds 2 and 3 of the DQM). Dissolution seems to have no role during these stages as shown by the unusual abundance and good preservation of the warm-tolerant Ac. sibaiyaensis. This species reaches its maximum abundance in Bed 2 where it exhibits a broad range of size (63–250 μm) and shape that probably reflect optimal growth under the warmest water conditions. Thus, we infer that temperature and dissolved oxygen content of the sea-water were the main factors controlling the distribution pattern(s) of the microplankton and microbenthos during the PETM.

The formation of the Isthmus of Panama stands as one of the greatest natural events of the Cenozoic, driving profound biotic transformations on land and in the oceans. Some recent studies suggest that the Isthmus formed manymillions of years earlier than the widely recognized age of approximately 3 million years ago (Ma), a result that if true would revolutionize our understanding of environmental, ecological, and evolutionary change across the Americas. To bring clarity to the question of when the Isthmus of Panama formed, we provide an exhaustive review and reanalysis of geological, paleontological, and molecular records. These independent lines of evidence converge upon a cohesive narrative of gradually emerging land and constricting seaways,withformationof theIsthmus of Panama sensustricto around 2.8 Ma. The evidence used to support an older isthmus is inconclusive, and we caution against the uncritical acceptance of an isthmus before the Pliocene., Facultad de Ciencias Naturales y Museo

The desertic Theban hills between the edge of the alluvial plain of the Nile River and the prominent cliffs at the eastern edge of the Theban Plateau consist of imbricated tilted blocks organized in parallel groups representing successive generations of gravitational collapse structures (or slumps). The older (distal) generations correspond to low, rounded hills farther from the Theban cliffs. The youngest (proximal) generation forms higher hills with young relief. The tilted blocks rest along listric faults on the substratum (Tarawan Chalk and Esna Shale Formations) and abut the Theban cliffs. Faults and warping occur at the contacts between proximal and distal tilted blocks. We hypothesize that the emplacements of the tilted blocks were related to major Pleistocene pluvial episodes, each marked by active flow of the Nile River and significant recess of the Theban cliffs. Tectonic thinning and intensive erosion of the Esna Shale Formation were determinant in shaping the Theban landscape.

We present a review of archaeological and geological studies on the West Bank as a basis for discussing the geological setting of the tombs and geologically related problems with a view to providing archaeologists with a framework in which to conduct their investigations on the restoration, preservation and management of the antique monuments. Whereas the geology of the Upper Nile Valley appears to be deceptively simple, the lithological succession is vertically variable, and we have recognized and defined several new lithological units within the upper Esna Shale Formation. We have been able to delineate lithological (shale/limestone) contacts in several tombs and observed that the main chambers in some were excavated below the Esna Shale in the Tarawan Chalk Formation. We have been able to document changing dip in the strata (warping) in several tombs, and to delineate two major orientations of fractures in the field. Investigations behind the Temple of Hatshepsut, in the Valley of the Kings and around Deir El Medina have revealed four broad regional structures. We confirm that the hills located near the Nile Valley, such as Sheik Abdel Qurna, do not belong to the tabular structure of the Theban Mountain, but are discrete displaced blocks including the Thebes Limestone, as supported by Google Earth photographs.

Planktonic foraminifera from a continuous Oligocene succession with clear magnetochronology and sediment cycles at Ocean Drilling Program Site 1218 (equatorial Pacific Ocean) were studied in the interval from 27 to 30 Ma. Paragloborotalia taxa are common and we examined their size, relative abundance, and stable isotopes. Multispecies stable isotope data indicate the depth habitats of Oligocene planktonic foraminifera and suggest that “Globoquadrina” venezuelana and Dentoglobigerina globularis were probably mixed-layer dwellers, with paragloborotaliids recording heavier δ 18 O signatures consistent with a thermocline habitat. Cyclic variations in the abundance of Paragloborotalia match eccentricity (100 kyr) variations in percent carbonate and δ 13 C, suggesting orbitally forced upwelling in the equatorial Pacific Ocean and that Paragloborotalia were responding directly to changes in surface water productivity. The high-resolution biostratigraphy calibrated to the magnetochronology constrains the extinction of Paragloborotalia opima which marks the top of Planktonic Foraminifera Biozone O5 (P21b) at 27.456 Ma. The highest occurrence of P. opima is associated with a 50% size decrease in Paragloborotalia pseudocontinuosa taxa within Chron 9n. In addition, we find the extinction of Chiloguembelina cubensis is consistent with other deep-sea sections within Chron 10n at 28.426 Ma marking the O4/O5 (P21a/P21b) boundary.

New biostratigraphic investigations on deep sea cores and outcrop sections have revealed several shortcomings in currently used tropical to subtropical Eocene plank­ tonic foraminiferal zonal schemes in the form of: 1) mod­ ified taxonomic concepts, 2) modifiel:l/different ranges of taxa, and 3) improved calibrations with magnetostratig­ raphy. This new information provides us with an op­ portunity to make some necessary improvements to ex­ isting Eocene biostratigraphic schemes. At the same time, we provide an alphanumeric notation for Paleo­ gene zones using the prefix 'P' (for Paleocene), 'E' (for Eocene) and '0' (for Oligocene) to achieve consistency with recent short-hand notation for other Cenozoic zones (Miocene ['M'], Pliocene [PL] and Pleistocene [PTD. Sixteen Eocene (E) zones are introduced (or nomen­ claturally emended) to replace the 13 zones and subzones of Berggren and others (1995). This new zonation serves as a template for the taxonomic and phylogenetic studies in the forthcoming Atlas of Eocene Planktonic Forami­ nifera (Pearson and others, in press). The 10 zones and subzones of the Paleocene (Berggren and others, 1995) are retained and renamed and/or emended to reflect im­ proved taxonomy and an updated chronologic calibra­ tion to the Global Polarity Time Scale (GPTS) (Berggren and others, 2000).' The PaleocenelEocene boundary is correlated with the lowest occurrence (LO) of Acarinina sibaiyaensis (base of Zone El), at the top of the trun­ cated and redefined (former) Zone P5. The five-fold zonation of the Oligocene (Berggren and others, 1995) is modified to a six-fold zonation with the elevation of (former) Subzones P21a and P21b to zonal status. The Oligocene (0) zomil' components are re­ named and/or nomenclaturally emended.

The geology of the Darien province of eastern Panama is presented through a new geologic map and detailed biostratigraphic and paleobathymetric analysis of its Upper Cretaceous to upper Miocene sediments. The sequence of events inferred from the stratigraphic record includes the collision of the Panama arc (the southwestern margin of the Caribbean plate) and South American continent. Three tectonostratigraphic units underlie the Darien region: (1) Precollisional Upper Cretaceous–Eocene crystalline basement rocks of the San Blas Complex form a series of structurally complex topographic massifs along the northeastern and southwestern margins of the Darien province. These rocks formed part of a >20 m.y. submarine volcanic arc developed in a Pacific setting distant from the continental margin of northwestern South America. The northerly basement rocks are quartz diorites, granodiorites, and basaltic andesites, through dacites to rhyolites, indicating the presence of a magmatic arc. The southerly basement rocks are an accreted suite of diabase, pillow basalt, and radiolarian chert deposited at abyssal depths. Precollisional arc-related rocks, of Eocene to lower Miocene age, consist of 4000 m of pillow basalts and volcaniclastics, and biogenic calcareous and siliceous deep-water sediments. They consist of the Eocene-Oligocene Darien Formation, the Oligocene Porcona Formation and the lower-middle Miocene Clarita Formation. Postcollisional deposits are mostly coarse- to fine-grained siliciclastic sedimentary rocks and turbiditic sandstone of upper middle to latest Miocene age. This 3000 m thick sedimentary sequence is deformed as part of a complexly folded and faulted synclinorium that forms the central Chucunaque-Tuira Basin of the Darien. The sedimentary package reveals general shallowing of the basin from bathyal to inner neritic depths during the 12.8−7.1 Ma collision of the Panama arc with South America. The sediments are divided into the upper middle Miocene Tapaliza Formation, the lower upper Miocene Tuira and Membrillo Formations, the middle upper Miocene Yaviza Formation, and the middle to upper Miocene Chucunaque Formation. The precollisional open marine units of Late Cretaceous–middle Miocene age are separated from the overlying postcollisional sequence of middle to late Miocene age by a regional unconformity at 14.8−12.8 Ma. This unconformity marks the disappearance of radiolarians, the changeover of predominantly silica deposition from the Atlantic to the Pacific, the initiation of the uplift of the isthmus of Panama, and the onset of shallowing upward, coarser clastic deposition. This pattern is also recorded from the southern Limon Basin of Caribbean Costa Rica to the Atrato Basin of northwestern Colombia. By the middle late Miocene, neritic depths were widespread throughout the Darien region, and a regional unconformity suggests completion of the Central American arc collision with South America by 7.1 Ma. No Pliocene deposits are recorded from either the Darien or the Panama Canal Basin, and no sediments younger than 4.8 Ma have been identified in the Atrato Basin of Colombia, suggesting rapid uplift and extensive emergence of the Central American isthmus in the latest Miocene. Northward movement of the eastern segment of the Panama arc along a now quiescent Panama Canal Zone fault during Eocene-Oligocene time may have dislocated the pre-collision arc. Since collision, the portion west of this fault (Chorotega Block) has remained stable, without rotation; to the east, in the Darien region, compression has been accommodated through formation of a Panama microplate with convergent boundaries to the north (North Panama deformed belt) and south (South Panama deformed belt), and suturing with South America along the Atrato Valley. Deformation within the microplate has been accommodated in the Darien province by several major left-lateral strike-slip faults that were active until the early Pliocene, since when the plate has behaved rigidly.

Recent revised magnetostratigraphic and astrochronologic calibrations of several calcareous planktonic microfossil datum events (in particular Coccolithus miopelagicus and Neogloboquadrina acostaensis) combined with our magnetobiostratigraphic investigation of a 10 m-thick section at Ecotet, near Lyon (France), in which terrestrial micromammals (Vallesian Zone MN9) are intercalated with calcareous nannoplankton and planktonic foraminifera belonging to Zones NN6^NN8 and N14^15 ( = M11 and M12), respectively, lead us to question the recent recalibration by Krijgsman et al. [(1996) Eart Planet. Sci. Lett. 142, 367^380) of the Aragonian/Vallesian (MN7^8/ MN9) boundary with Chron C5r.1r (V11.1 Ma) and the lower/upper Vallesian (MN9/10) boundary with Chron C4Ar.2n (V9.6^9.7 Ma). Ecotet, with a uniform reverse polarity, is shown to be assignable uniquely to Chron C5r. Interregional correlation of Ecotet with Mediterranean terrestrial stratigraphies indicates that Progonomys (whose First Occurrence (FO) has been traditionally placed in Mediterranean Mammal Zone MN10) was already present in Mediterranean Zone MN9 at V11.4 Ma and did not experience a 2 million-year delay in its putative prochoresis from Asia.

We describe the planktonic foraminiferal biostratigraphy of the ~61m thick stratigraphic section spanning the Tarawan Chalk (~17 m) and Esna Shale (~44 m) at Gebel Owaina and the ~35m thick section spanning the total thickness of the Esna Shale at Gebel Kilabiya, ~10km west of Owaina. The Owaina section spans Zones P4a ( partim ) to P6a ( partim ), whereas Kilabiya spans Zones P4c ( partim ) to P6a ( partim ). The Esna/Thebes contact at both localities is marked by a distinct angular unconformity within Zone P6a and a hiatus estimated >3 my; the sections are thus considerably less complete than at Dababiya, ~25km to the north. The recently revised Paleocene/Eocene boundary is located in both sections within the lower part of the Esna Shale at ~12m and 16.3m, respectively, above the base of the Esna Shale. The CIE-interval is reduced in both sections (~1m thick at G. Owaina and ~1.5m at G. Kilabiya) and exhibits evidence of a stratigraphic gap/hiatus within its upper part at both localities. The base of the CIE-interval is characterized by the lowest occurrences (LO) of Acarinina sibaiyaensis and marked at its top by the LO of Pseudohastigerina wilcoxensis . At Gebel Owaina the CIE-interval is directly preceded by the LO of Ac. wilcoxensis, Ac. angulosa , Acarinina esnaensis and Igorina broedermanni in descending order, whereas at Kilabiya this sequential order of bioevents is less well developed. Although the characteristic paleontologic trends observed elsewhere are subdued in the Kilabiya section, the latter shows a phased pattern within the CIE-interval comparable to that of the Dababiya Quarry Beds at Dababiya.

Because Upper Egypt (stable shelf, pre-rift) contains some of the most expanded and continuous stratigraphic records of the biologic and chemical changes across the P-E transition, the P/E Boundary Working Group have conducted over the course of the last four years a series of integrated studies on this anomalous interval. These studies have led to the recognition of several bio- and chemostratigraphic events that can serve to denote the P/E boundary and to correlate upper Paleocene-lower Eocene stratigraphic successions that were deposited at different bathymetries in the southern Nile Valley. The main bioevents that occur within this stratigraphic interval (that spans from the upper Tarawan Limestone to the basal Thebes Limestone, and ecompasses the entire Esna Shale Formation) are identified and correlated in terms of pre-CIE-Interval, CIE-Interval and post-CIE-Interval. Faunal patterns and mechanism of faunal changes as well as paleoecologic inferences from these changes are described and discussed for the warming episode associated with the CIE-interval as well as for the intervals immediately preceding and following it. Stratigraphic correlations of upper Paleocene-lower Eocene sections in the southern Nile Valley are correlated based on the most prominent events. The biostratigraphy of the Tarawan Chalk and Esna Shale are correlated with the Integrated Magnetobiostratigraphic scale of Berggren et al. (1995). The vertical (stratigraphic) and lateral (geographic) changes in biota and depositional environments and their facies variants are examined over ~300 km from the vicinity of Qena (in the north) to Wadi Abu Ghurra in the southwestern Nile Valley.

We describe the lithostratigraphy and planktonic foraminiferal biostratigraphy of the upper Paleocene- lowermost Eocene (Zones P4a-P5c) stratigraphic section exposed in a neritic/shelf carbonate setting at Wadi Abu Ghurra in the southern part of the Upper Nile Valley. The 2.5cm thick PETM-correlative interval lacks the phosphatic-coprolitic horizon(s) typical of the Dababiya Quarry Beds to the north, but does contain elements ( Acarinina africana, Ac. sibaiyaensis and M. allisonensis ) of the planktonic foraminifera excursion taxa (PFET). The PETM-correlative interval is bracketed (below) by the LO of Acarinina esnaensis, Igorina broedermanni, Ac. angulosa and Ac. wilcoxensis and (above) the LO of Pseudohastigerina wilcoxensis. The top of the inferred PETM-interval coincides with the Garra / Dungul formational contact and is marked by an abrupt enrichment in planktonic foraminifera together with a low-diversity benthic foraminiferal association, comparable to those of the calcarenites which terminate the Dababiya Quarry Beds in deeper water sections in the north. Angulogavelinella avnimelechi , together with several long-ranging Paleocene benthic forms, have their HO at the base of the PETM-interval, whereas dimorphic larger foraminifera ( Discocyclina , Operculina , primitive Nummulites ) have their LO at its top.

We describe the upper Paleocene-lower Eocene planktonic foraminiferal biostratigraphy at Qreiya (southeastern exposure of Gebel Abu Had), about 50km ENE of Qena, Egypt. The ~54m thick section spans the Tarawan Chalk (~8.6m thick; Zone P4a+b) and the Esna Shale (~45m thick; Zones P4c-P7, partim ). The Tarawan/Esna contact is paraconformable, and coincident with the NP8/NP9 and P4a+b/P4c zonal boundaries. The Esna Shale is subdivided into units, and the Dababiya Quarry Beds (=CIE-interval) lie at the base of Unit Esna 2, whereas Unit Esna 3 is much reduced in thickness owing to an unconformity that separates Zones P6/P7 cutting out ~ 40+m of the upper Esna Shale. The Esna Shale/Thebes Limestone contact is probably also unconformable inasmuch as it lies within Zone P7, whereas at Dababiya it lies within Zone P8. The ~2.4m thick CIE-interval is located in the lower part of the Esna Shale, 7.2m above the top of the Tarawan Chalk and is divided into three distinct lithic components as at Dababiya. Quantitative analysis of the planktonic foraminifera spanning the interval from 2.6m below, through, and to 1m above the CIE, has revealed significant assemblage change patterns and enabled precise inter-locality correlation with the Dababiya Quarry and Owaina sections.

A newly discovered sequence of lower to middle Miocene rocks from the eastern Bocas del Toro archipelago, western Panama, reveals the timing and environment of the earliest stages in the rise of the Isthmus of Panama in this region. Two new formations, the Punta Alegre Formation (lower Miocene, Aquitanian to Burdigalian) and the Valiente Formation (middle Miocene, Langhian to Serravallian), are here named and formally described. The Punta Alegre Formation contains a diagnostic microfauna of benthic and planktic foraminifera and calcareous nannofossils that indicate deposition in a 2000-m-deep pre-isthmian neotropical ocean from as old as 21.5-18.3 Ma. Its lithology varies from silty mudstone to muddy foraminiferal ooze with rare thin microturbidite layers near the top. The Valiente Formation, which ranges in age from 16.4 to ca. 12.0 Ma, lies with slight angular unconformity on the Punta Alegre Formation and consists of five lithofacies: (1) columnar basalt and flow breccia, (2) pyroclastic deposits, (3) coarse-grained volcaniclastic deposits, (4) coral-reef limestone with diverse large coral colonies, and (5) marine debris-flow deposits and microturbidites. These lithofacies are interpreted to indicate that after ca. 16 Ma a volcanic arc developed in the region of Bocas del Toro and that by ca. 12 Ma an extensively emergent archipelago of volcanic islands had formed. 3 9 Ar/ 4 0 Ar dating of basalt flows associated with the fossiliferous sedimentary rocks in the upper part of the Valiente Formation strongly confirms the ages derived from planktic foraminifera and nannofossils. Paleobathymetric analysis of the two new formations in the Valiente Peninsula and Popa Island, in the Bocas del Toro archipelago, shows a general shallowing from lower- through upper-bathyal to upper-neritic and emergent laharic and fluviatile deposits from ca. 19 to 12 Ma. The overlying nonconformable Bocas del Toro Group contains a lower transgressive sequence ranging from basal nearshore sandstone to upper-bathyal mudstone (ca. 8.1-5.3 Ma) and an upper regressive sequence (5.3-3.5 Ma). A similar paleobathymetric pattern is observed from the Gatun to Chagres Formations (12-6 Ma) in the Panama Canal Basin area and in the Uscari, Rio Banana, Quebrada Chocolate, and Moin Formations (8-1.7 Ma) in the southern LimOn Basin of Costa Rica.

Surface and deep water circulation patterns in the eastern Indian Ocean during the Paleocene Epoch are inferred based on an integrated magnetobiostratigraphic and stable isotope investigation of Ocean Drilling Program Hole 761B, drilled on the Wombat Plateau. A combination of magnetostratigraphy, biostratigraphy and isotope stratigraphy demonstrates that numerous deep sea sites that have been considered to show continuous, or nearly continuous sedimentation through the Paleocene are punctuated by a series of hiatuses, some of which exceeding a duration of 1 Myr. Therefore, our study is based on a detailed temporal interpretation of the stratigraphic successions we used for paleoceanographic reconstructions. We compare detailed planktonic and benthic foraminiferal carbon and oxygen isotope records from Hole 761B with several temporally correlative records published from different oceanic provinces in order to distinguish between local and global patterns within the eastern Indian Ocean. Although Site 761 was situated at low latitudes during the Paleocene, its surface waters were predominantly influenced by circulation originating from the Southern Ocean as indicated by inferred cool sea surface temperatures and reduced surface to deep water temperature gradients. We suggest that deep waters in the eastern Indian Ocean were not directly fed by the Southern or Tethys Oceans. Rather, the more negative N 13 C composition of the bottom waters recorded by benthic foraminifera implies the presence and/or active contribution of aged deep waters from the Pacific during this time, at least prior to V60.2 Ma and subsequent to V59.0 Ma. The Indian continent, Ninetyeast Ridge, Kerguelen Plateau and Broken Ridge may have played a significant role as submarine barriers to deep water circulation during the Paleocene. ; 2002 Elsevier Science B.V. All rights reserved.

Extinction and evolutionary events in planktonic foraminifera are extensively employed in regional and global biostratigraphy and are a fundamental component of Cenozoic chronostratigraphy. The calibration of planktonic foraminiferal events has been based largely on correlations to the magnetostratigraphy in Deep Sea Drilling Project and Ocean Drilling Programme cores, as well as to outcrop sections (Berggren et al. 1995; Wade et al. 2011). However, the calibration of many Palaeogene planktonic foraminiferal events has been hindered by poor core recovery, the absence of biogenic carbonate, and a lack of magnetostratigraphic and/or cyclostratigraphic age control.

At Deep Sea Drilling Site 384 (J-Anomaly Ridge, Grand Banks Continental Rise, NW Atlantic Ocean) Paleocene nannofossil chalks and oozes (∼70 m thick) are unconformably/disconformably underlain (∼168 m; upper Maastrichtian) and overlain (∼98.7 m; upper lower Eocene) by sediments of comparable lithologies. The chalks are more indurated in stratigraphically higher levels of the Paleocene reflecting increasing amounts of biosiliceous (radiolarians and diatoms) components. This site serves as an excellent location for an integrated calcareous and siliceous microfossil zonal stratigraphy and stable isotope stratigraphy. We report the results of a magnetostratigraphic study which, when incorporated with published magnetostratigraphic results, reveals an essentially complete magnetostratigraphic record spanning the interval from Magnetochron C31n (late Maastrichtian) to C25n (partim) (late Paleocene, Thanetian). Integrated magnetobiochronology and stable isotope stratigraphy support the interpretation of, and constrain the estimated duration of, a short hiatus (∼0.9 my) within the younger part of Chron C29r (including the K/P boundary) and an ∼6 my hiatus separating upper Paleocene (Magnetozone C25n) and upper lower Eocene (Magnetozone C22r) sediments. Some 30 planktonic foraminiferal datum levels [including the criteria used to denote the Paleocene planktonic foraminiferal (sub)tropical zonal scheme of Berggren and Miller, Micropaleontology 34 (4) (1988) 362–380 and Berggren et al., SEPM Spec. Publ. 54 (1995) 129–212, Geol. Soc. Am. Bull. 107 (11) (1995) 1272–1287], and nearly two dozen calcareous nannoplankton datum levels have been recognized and calibrated to the magnetochronology. Planktonic foraminiferal Subzones P4a and P4b of (upper Paleocene) Zone P4 are emended/redefined based on the discovery of a longer stratigraphic extension of Acarinina subsphaerica (into at last Magnetozone C25n). Stable isotope stratigraphies from benthic foraminifera and fine fraction (

Stratigraphy is a magnificent subject—magnificent in its breadth and scope, magnificent in its importance to so many lines of human endeavor. It is essentially that branch of geology which deals with the arrangement, the distribution, and the chronological succession of rock strata (and other associated rock bodies), with respect to any or all of the various characters, properties, and attributes which rocks may possess (Hedberg, 1958, p. 1881). Chronostratigraphy—the temporal ordering of geologic strata—is at the heart of earth history. In reviewing chronostratigraphic theory, from d'Orbigny to Hedberg, we see that concepts and practices have evolved under pressure of constant improvements in time control and data quality. Such stimuli are naturally felt more strongly in the youngest part of the stratigraphic record, where dating is most precise and the biostratigraphic data are most abundant and well-preserved. It is not surprising, therefore, to find that chronostratigraphy is conceptually more advanced in the Cenozoic Erathem than in the Mesozoic and Paleozoic Erathems, where biostratigraphy and chronostratigraphy are widely confused, evidently out of necessity. Taking the five inter-series boundaries in the Cenozoic Erathem as case histories, we review their current status in relation to the lower boundary of the lowest `standard' stage above the boundary, in light of the hierarchical principle recommended in the International Stratigraphic Guide ( Hedberg, 1976 ; Salvador, 1994 ). In each instance, what should be a simple nested relationship turns out to be complex and difficult, and in the cases of the proposed global stratotype section and point (GSSPs) for the Eocene/Oligocene Series boundary and the Paleocene/Eocene Series boundary there are discrepancies so large with regard to the base of the Rupelian and Ypresian standard stages, respectively, that some essential relaxation of the hierarchic rule seems to be required if the historic value of these long-known stages is not to be violated. Since stage boundaries should not be defined a posteriori to fit series boundaries, we propose here to reconsider the role of the Standard Stage as the obligate elemental subdivision in a rigidly hierarchical chronostratigraphic scale and suggest that series and subseries should be formalized and their boundaries defined by GSSPs. We do not suggest that stages be abandoned. On the contrary, we propose to integrate them in a two-step hierarchical chronostratigraphic framework, so as to use them in complementary fashion with series and subseries. However, the boundary concept is more appropriate for stage than the GSSP. We recognize the need for precise and globally valid chronostratigraphic correlations based on GSSPs in attempts to understand the earth system, while at the same time, we emphasize the need for conceptual continuity with regard to the central place that the stage has played in chronostratigraphy over several decades.

We present an integrated geochronology for late Neogene time (Pliocene, Pleistocene, and Holocene Epochs) based on an analysis of data from stable isotopes, magnetostratigraphy, radiochronology, and calcareous plankton biostratigraphy. Discrepancies between recently formulated astronomical chronologies and magnetochronologies for the past 6 m.y. have been resolved on the basis of new, high-precision Ar/Ar ages in the younger part of this interval, the so-called Brunhes, Matuyama, and Gauss Epochs (= Chrons C1n-C2An; 0-3.58 Ma), and revised analysis of sea floor anomalies in the Pacific Ocean in the older part, the so-called Gilbert Epoch (= Chron C2Ar-C3r; 3.58-5.89 Ma). The magneto- and astrochronologies are now concordant back to the Chron C3r/C3An boundary at 5.89 Ma. The Neogene (Miocene, Pliocene, Pleistocene, and Holocene) and Paleogene are treated here as period/system subdivisions of the Cenozoic Era/Erathem, replacements for the antiquated terms Tertiary and Quaternary. The boundary between the Miocene and Pliocene Series (Messinian/Zanclean Stages), whose global stratotype section and point (GSSP) is currently proposed to be in Sicily, is located within the reversed interval just below the Thvera (C3n.4n) Magnetic Polarity Subchronozone with an estimated age of 5.32 Ma. The Pliocene/Pleistocene boundary, whose GSSP is located at Vrica (Calabria, Italy), is located near the top of the Olduvai (C2n) Magnetic Polarity Subchronozone with an estimated age of 1.81 Ma. The 13 calcareous nannoplankton and 48 planktonic foraminiferal datum events for the Pliocene, and 12 calcareous nannoplankton and 10 planktonic foraminiferal datum events for the Pleistocene, are calibrated to the newly revised late Neogene astronomical/geomagnetic polarity time scale.

SEPM Pacific Section No. 91, Donald R. Prothero (Editor), 2001: SEPM (Society for Sedimentary Geology, Pacific Section), 394 p. ($25 non-members, $22 members) ISBN: I-878861-84-0. If there are any of you reading this review who still believe in the general continuity of sedimentation over long intervals of time and the concomitant accumulation of uninterrupted successions of sedimentary strata (i.e., that time and stratigraphy are interchangeable) as a general, if not inclusive, rule, this volume should come as a sobering wake-up call. The theme that keeps reverberating throughout this volume is Ager's prescient dictum/revelation, uttered now these 30 years ago, that the stratigraphic sequence/record in any given area is “more gaps than record.” This has been demonstrated clearly in the deep-sea record by the integrated magnetobiostratigraphic studies of Aubry (1993, 1995) on the Neogene and Paleogene, respectively. This is not to deny that essentially continuous depositional sequences do not occur in the stratigraphic record (recent advances in astrochronology/cyclostratigraphy would not have been possible were it not for the accumulation of such sequences), but rather to point out that non-depositional or erosional unconformities are a common feature in the stratigraphic record and must be assiduously considered in any attempt to place geologic events in an historical context. The Cenozoic stratigraphic record of the Pacific Coast has resisted attempts to place its constituent components into a neat bio- and chronostratigraphic framework. Being situated in a region of extensive tectonic activity and bathed by southward moving cold-water currents (and concomitant lack of biostratigraphically useful low latitude planktonic microfossils), early paleontologists resorted to using …

Planktonic foraminifera are widely utilized for the biostratigraphy of Cretaceous and Cenozoic marine sediments and are a fundamental component of Cenozoic chronostratigraphy. The recent enhancements in deep sea drilling recovery, multiple coring and high resolution sampling both offshore and onshore, has improved the planktonic foraminiferal calibrations to magnetostratigraphy and/or modified species ranges. This accumulated new information has allowed many of the planktonic foraminiferal bioevents of the Cenozoic to be revised and the planktonic foraminiferal calibrations to be reassessed. We incorporate these developments and amendments into the existing biostratigraphic zonal scheme. In this paper we present an amended low-latitude (tropical and subtropical) Cenozoic planktonic foraminiferal zonation. We compile 187 revised calibrations of planktonic foraminiferal bioevents from multiple sources for the Cenozoic and have incorporated these recalibrations into a revised Cenozoic planktonic foraminiferal biochronology. We review and synthesize these calibrations to both the geomagnetic polarity time scale (GPTS) of the Cenozoic and astronomical time scale (ATS) of the Neogene and late Paleogene. On the whole, these recalibrations are consistent with the previous work; however, in some cases, they have led to major adjustments to the duration of biochrons. Recalibrations of the early–middle Eocene first appearance datums of Globigerinatheka kugleri, Hantkenina singanoae, Guembelitrioides nuttalli and Turborotalia frontosa have resulted in large changes in the durations of Biochrons E7, E8 and E9. We have introduced (upper Oligocene) Zone O7 utilizing the biostratigraphic utility of ‘Paragloborotalia’ pseudokugleri. For the Neogene Period, major revisions are applied to the fohsellid lineage of the middle Miocene and we have modified the criteria for recognition of Zones M7, M8 and M9, with additional adjustments regarding the Globigerinatella lineage to Zones M2 and M3. The revised and recalibrated datums provide a major advance in biochronologic resolution and a template for future progress of the Cenozoic time scale

We present the results of a paleontological study of samples collected during the Vemanaute cruise on the Vema Fracture Zone southern wall where an almost complete section of oceanic crust is exposed. The three studied samples are poorly lithified yellowish calcareous sediments lying horizontally over gabbros. They contain abundant, generally well-preserved, and relatively diverse tropical late Neogene calcareous nannofloras and planktonic foraminiferal faunas, and yield a few poorly preserved radiolarians. The estimated ages are 8.8–10 Ma; 5.6–6.4 Ma (late Miocene); 4.5–4.2 Ma (early Pliocene), derived from deepsea correlations between microfossil zonations and magnetic stratigraphy. Our results are compared to theoretical ages proposed for the crust in the surveyed area. This leads us to discuss the timing and location of mechanisms responsible for the exposure of the observed section and allows us to emphasize that early morphologies and structures may be preserved during the transform walls migration.

1School of Earth, Ocean and Planetary Sciences, Cardiff University, Main Building, Park Place, Cardiff CF10 3YE, U.K. pearsonp@Cardiff.ac.uk 2Department of Geological Sciences, Rutgers University, New Brunswick, New Jersey 08903, U.S.A. 3Department of Paleobiology, MRC NHB 121, National Museum of Natural History, Smithsonian Institution, Washington, D.C., U.S.A. 4Institute und Museum fur Geologie und Palaontologie, Universitat Tubingen, D-72076, Germany 5Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, U.S.A. 6Laboratory Research Department, INA, NAFTAPLIN, HR/10000, Zagreb, Croatia 7Dipartimento Scienze della Terra, University of Milan, Via Mangiagalli 34, 20133 Milano, Italy

The Global Standard Stratotype-section (GSSP) for the Paleocene/Eocene (P/E) boundary has been selected in the Dababiya Quarry, near Luxor, at the base of a lithostratigraphic unit where the base of the so-called Carbon Isotope Excursion (CIE) is recorded. The Dababiya Quarry offers remarkable three-dimensional exposures of the Upper Paleocene-Lower Eocene succession in the Nile Valley which comprises the Tarawan Chalk, the Esna Shale and the Thebes Limestone. The horizon that constitutes the P/E GSSP is located in the lower part of the Esna Shale Formation. This formation, remarkably thick (similar to 130m) at Dababiya, is largely of homogenous gray shales. Its lower part includes, however, a thin lithostratigraphic unit in a typical succession of five characteristic beds that can be followed throughout Upper Egypt, and at the base of which the GSSP is defined. We formally describe this unit as the Dababiya Quarry Beds at the same time as we subdivide the Esna Shale Formation into three formal lithostratigraphic units. The Dababiya Quarry Beds constitute the lower part of Unit Esna 2. While we place emphasis on the description of the lithology, mineralogy, carbon isotope stratigraphy and paleontology of the Dababiya Beds, we provide a mineralogic and biostratigraphic framework for the whole exposure of Esna Shale at Dababiya that constitutes essentially a complete record from the base of calcareous nannofossil Zone NP9 to Zone NP11 and planktonic foraminiferal Zone P4 to P8. The carbon isotopic excursion, measured on organic matter is similar to3m thick and has an amplitude of similar to4%. The planktonic foraminiferal excursion taxa are sporadic and the distinct Discoaster araneus Rhomboaster spp. association is persistent throughout the CIE-interval. ispartof: Micropaleontology vol:49 issue:SUPPLEMENT 1 pages:41-59 status: published

An ITS is a calendar of magnetic reversals and palaeontological events. The elements of an ITS consist of: (1) a Global Polarity Time Scale (GPTS) based on distances between magnetic anomalies on the sea floor; (2) analytically precise radioisotopic ages used to calibrate the GPTS; (3) precise magnetobiostratigraphic correlations from which a biochronology is derived (including the correct correlation between magnetozones and sea floor anomalies). Keywords: geochronology; stratigraphy; biostratigraphy; radiometric dating; astrochronology; international stratigraphic commission

The formal recognition of Quaternary as a Period/ System was approved by IUGS in June 2009, in accordance with a proposal originated by INQUA. There are reasons to believe that this will have destabilizing consequences for the geological time scale. Until now, the primary divisions of the stratigraphic record, at the Period level and above, have been based on the progressive change of Earth's biota. The Quaternary, on the other hand, is a paleoclimatic concept based on glacial-interglacial variability, expressed in lithological change. The IUGS vote holds that this paradigm now supersedes the biochronological identity of the Neogene Period/System. Furthermore, to accomodate the most recent INQUA opinion about "when the Ice Ages began", the ICS agreed to relocate the base of the Pleistocene to 2.59 Ma from 1.81 Ma, enlarging the epoch by 43% and again without regard for its original paleontological definition, or for the vast literature in other fields of Pleistocene research. If history is a guide, the resulting disruption in late Cenozoic marine and vertebrate paleontology, human evolution, paleoceanography and paleoclimatology will be widely resisted, with potential impact on the authority of IUGS. The consequence of abandoning basic principles in order to satisfy the interest of a special group deserves a wider consideration than it has so far received.

With the loss of expertise in the various (sub)disciplines of micropaleontology gathering momentum owing to a variety of reasons, the need for synoptic overviews has become increasingly apparent. Thus over the last 20 years we have seen the publication of Atlases of Cenozoic Cosmopolitan Deep Water Benthic Foraminifera (CCDWBF), Cretaceous, Paleocene (and soon to appear, Eocene) planktonic foraminifera and a series of Handbooks on Cenozoic calcareous nannoplankton. Deep Water Agglutinated Foraminifera (DWAF) are characteristic of siliclastic deposits from flysch basins as well as deep sea deposits around the world. They have been noticeably neglected (with the exception of a devoted minority of specialists) owing to the difficulty in analyzing their relatively simple and esthetically pedestrian morphology. However, their usefulness has been recognized in deciphering the (bio)stratigraphy of petroliferous flysch basins ever since the pioneering studies of Jozef Grzybowksi in the Carpathian Mountains of Poland at the end of the 19th century. With the publication of this Atlas DWAF have taken their place at High Table! This volume is the result of over 20 years …

Since the publication of our previous time scale (Berggren and others, 1985c = BKFV85) a large amount of new magneto- and biostratigraphic data and radioisotopic ages have become available. An evaluation of some of the key magnetobiostratigraphic calibration points used in BKFV85, as suggested by high precision 40 Ar/ 39 Ar dating (e.g., Montanari and others, 1988; Swisher and Prothero, 1990; Prothero and Swisher, 1992; Prothero, 1994), has served as a catalyst for us in developing a revised Cenozoic time scale. For the Neogene Period, astrochron- ologic data (Shackleton and others, 1990; Hilgen, 1991) required re-evaluation of the calibration of the Pliocene and Pleistocene Epochs. The significantly older ages for the Pliocene-Pleistocene Epochs predicted by astronomical calibrations were soon corroborated by high precision 40 Ar/ 39 Ar dating (e.g., Baksi and others, 1992; McDougall and others, 1992; Tauxe and others, 1992; Walter and others, 1991; Renne and others, 1993). At the same time, a new and improved definition of the Late Cretaceous and Cenozoic polarity sequence was achieved based on a comprehensive evaluation of global sea-floor magnetic anomaly profiles (Cande and Kent, 1992). This, in turn, led to a revised Cenozoic geomagnetic polarity time scale (GPTS) based on standardization to a model of South Atlantic spreading history (Cande and Kent, 1992/1995 = CK92/95). This paper presents a revised (integrated magnetobiochronologic) Cenozoic time scale (IMBTS) based on an assessment and integration of data from several sources. Biostratigraphic events are correlated to the recently revised global polarity time scale (CK95). The construction of the new GPTS is outlined with emphasis on methodology and newly developed polarity history nomenclature. The radioisotopic calibration points (as well as other relevant data) used to constrain the GPTS are reviewed in their (bio)stratigraphic context. An updated magnetobiostratigraphic (re)assessment of about 150 pre-Pliocene planktonic foraminiferal datum events (including recently avail- able high southern (austral) latitude data) and a new/modified zonal biostratigraphy provides an essentially global biostratigraphic correlation framework. This is complemented by a (re)assessment of nearly 100 calcareous nannofossil datum events. Unrecognized unconformities in the stratigraphic record (and to a lesser extent differences in taxonomic concepts), rather than latitudinal diachrony, is shown to account for discrep- ancies in magnetobiostratigraphic correlations in many instances, particularly in the Paleogene Period. Claims of diachrony of low amplitude (

Werner E. Piller and Michael W. Rasser (Eds.), 2001, Osterrreichische Akademie der Wissenschaften, Band 14, Verlag der Osterreichischen Akademie der Wissenshaften, (Austrian Academy of Sciences Press), Vienna, Austria, 795 p. (Order online from the Austrian Academy of Sciences (http://verlag.oeaw.ac.at/eindex.html) 84 ![Graphic][1] , ∼$82 US) ISBN: 3-7001-3011-2. The Eastern Alps are the result of the (still) active convergence/subduction between Africa and Europe. Beginning with the consolidation of the Austroalpine nappe complex during the Late Cretaceous, the subsequent history/evolution of this area was denoted by the latest Cretaceous and Paleogene subduction of the Penninic oceanic region, followed by collision between the Penninic and Austroalpine units. Paleogene orogeny was controlled by a combination of subduction, collisional tectonics (uplift of the Alpine orogen during the late Eocene), and eventual closure of the Penninic oceanic areas. This formed an archipelago separating the shallow, inland sea, the Paratethys, in the north and Tethys/Mediterranean Sea in the south. By the mid-Miocene there was the eventual closure of the Tethyan Ocean followed by its evolution/metamorphosis into eastern and western segments, and, finally (latest Miocene-early Pliocene) into the last remnant of the once extensive Tethyan Ocean, the modern Mediterranean Sea. The late Paleogene (latest Eocene) closure of the Penninic Oceanic realm was characterized by the cessation of the long-standing, deep-water flysch sedimentation (and its characteristic sedimentologic features and faunas in the form of agglutinated benthic foraminiferal assemblages) and the initiation of Molasse (silicilastic) sedimentation in the foreland basins north of the Alpine orogen. Anyone who has struggled to understand the complex geologic history of the Alpine system of Europe based upon the available literature has sympathized with those who have conducted the primary investigations in this region. Life has just been made a little easier for many of us, however, at least with regards to a … [1]: /embed/inline-graphic-1.gif

The transition from the Eocene to the Oligocene epoch was the most significant event in Earth history since the extinction of dinosaurs. As the first Antarctic ice sheets appeared, major extinctions and faunal turnovers took place in the land and in the sea, eliminating forms adapted to a tropical world and replacing them with the ancestors of most of our modern animal and plant life. Through a detailed study of climatic conditions and of organisms buried in Eocene-Oligocene sediments, this volume shows that the separation of Antarctica from Australia was a critical factor in changing oceanic circulation and ultimately world climate. In this book, contributors examine the full range of Eocene and Oligocene phenomena. Their articles cover nearly every major group of organisms in the ocean and on land and include evidence from palaeontology, stable isotopes, sedimentology, seismology and computer climatic modelling. The volume concludes with an update of the geochronological framework of the late Palaeogenic period.