ALBERT

Description: Author Posting. © Cushman Foundation for Foraminiferal Research, 2005. This article is posted here by permission of Cushman Foundation for Foraminiferal Research for personal use, not for redistribution. The definitive version was published in Journal of Foraminiferal Research 35 (2005): 279-298, doi:10.2113/35.4.279.

Description: New biostratigraphic investigations on deep sea cores and outcrop sections have revealed several shortcomings in currently used tropical to subtropical Eocene planktonic foraminiferal zonal schemes in the form of: 1) modified taxonomic concepts, 2) modified/different ranges of taxa, and 3) improved calibrations with magnetostratigraphy. This new information provides us with an opportunity to make some necessary improvements to existing Eocene biostratigraphic schemes. At the same time, we provide an alphanumeric notation for Paleogene zones using the prefix ‘P’ (for Paleocene), ‘E’ (for Eocene) and ‘O’ (for Oligocene) to achieve consistency with recent short-hand notation for other Cenozoic zones (Miocene [’M’], Pliocene [PL] and Pleistocene [PT]). Sixteen Eocene (E) zones are introduced (or nomenclaturally 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 Foraminifera (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 improved taxonomy and an updated chronologic calibration to the Global Polarity Time Scale (GPTS) (Berggren and others, 2000). The Paleocene/Eocene boundary is correlated with the lowest occurrence (LO) of Acarinina sibaiyaensis (base of Zone E1), at the top of the truncated 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 (O) zonal components are renamed and/or nomenclaturally emended.

Description: Author Posting. © Austrian Geological Society, 2012. This article is posted here by permission of Austrian Geological Society for personal use, not for redistribution. The definitive version was published in Austrian Journal of Earth Sciences 105, no. 1 (2012): 161-168.

Description: The Dababiya corehole was drilled in the Dababiya Quarry (Upper Nile Valley, Egypt), adjacent to the GSSP for the Paleocene/ Eocene boundary, to a total depth of 140 m and bottomed in the lower Maastrichtian Globotruncana aegyptiaca Zone of the Dakhla Shale Formation. Preliminary integrated studies on calcareous plankton (foraminifera, nannoplankton), benthic foraminifera, dinoflagellates, ammonites, geochemistry, clay mineralogy and geophysical logging indicate that: 1) The K/P boundary lies between 80.4 and 80.2 m, the Danian/Selandian boundary between ~ 41 and 43 m, the Selandian/Thanetian boundary at ~ 30 m (within the mid-part of the Tarawan Chalk) and the Paleocene/Eocene boundary at 11.75 m (base [planktonic foraminifera] Zone E1 and [calcareous nannoplankton] Zone NP9b); 2) the Dababiya Quarry Member (=Paleocene/Eocene Thermal Maximum interval) extends from 11.75 to 9.5 m, which is ~1 m less than in the adjacent GSSP outcrop.; 3) the Late Cretaceous (Maastrichtian) depositional environment was nearshore, tropical-sub tropical and nutrient rich; the latest Maastrichtian somewhat more restricted (coastal); and the early Danian cooler, low(er) salinity with increasing warmth and depth of water (i.e., more open water); 4) the Paleocene is further characterized by outer shelf (~ 200 m), warm water environments as supported by foraminifera P/B ratios 〉 85% (~79-28 m), whereas benthic foraminifera dominate (〉70%) from ~27-12 m (Tarawan Chalk and Hanadi Member) due, perhaps, in part to increased dissolution (as observed in nearby outcrop samples over this interval); 5) during the PETM, enhanced hydrodynamic conditions are inferred to have occurred on the sea-floor with increased river discharge (in agreement with sedimentologic evidence), itself a likely cause for very high enhanced biological productivity on the epicontinental shelf of Egypt; 6) correlation of in situ measured geophysical logs of Natural Gamma Ray (GR), Single-Point Resistance (PR), Self-Potential (SP), magnetic susceptibility (MS), and Resistivity, and Short Normal (SN) and Long Normal (LN) showed correspondence to the lithologic units. The Dababiya Quarry Member, in particular, is characterized by very high Gamma Ray and Resistivity Short Normal values.

Description: The Dababiya corehole was made possible by the financial support of the National Geographic Society.

Description: Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of John Wiley & Sons for personal use, not for redistribution. The definitive version was published in Terra Nova 21 (2009): 237-256, doi:10.1111/j.1365-3121.2009.00872.x.

Description: We present a review of archeological 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 archeologists 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 lithologic succession is vertically variable, and we have recognized and defined several new lithologic units within the upper Esna Shale Formation. We have been able to delineate lithologic (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 Abel Qurna, do not belong to the tabular structure of the Theban Mountain, but are discrete displaced blocks of the Thebes Limestone and overlying El Miniya, as supported by Google Earth photographs.

Description: Author Posting. © The Author(s), 2010. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Earth-Science Reviews 104 (2011): 111-142, doi:10.1016/j.earscirev.2010.09.003.

Description: 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 a reassessment of the planktonic foraminiferal calibrations. 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 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 to the Cenozoic time scale.

Description: BSW acknowledges support from National Science Foundation (NSF) CAREER Award (EAR-0847300), Consortium for Ocean Leadership/NSF (OCE- 0352500) and the Natural Environment Research Council (NE/G014817/1).

Description: Author Posting. © Micropaleontology Press, 2009. This article is posted here by permission of Micropaleontology Press for personal use, not for redistribution. The definitive version was published in Stratigraphy 6 (2009): 1-16.

Description: The International Commission on Stratigraphy (ICS) together with its subcommissions on Neogene Stratigraphy (SNS) and Quaternary Stratigraphy (SQS) are facing a persistent conundrum regarding the status of the Quaternary, and the implications for the Neogene System/Period and the Pleistocene Series/Epoch. The SQS, in seeking a formal role for the Quaternary in the standard time scale, has put forward reasons not only to truncate and redefine the Neogene in order to accommodate this unit as a third System/Period in the Cenozoic, but furthermore to shift the base of the Pleistocene to c. 2.6 Ma to conform to a new appreciation of when “Quaternary climates” began. The present authors, as members of SNS, support the well-established concept of a Neogene extending to the Recent, as well as the integrity of the Pleistocene according to its classical meaning, and have published arguments for workable options that avoid this conflict. In this paper, we return to the basic principles involved in the conversion of the essentially marine biostratigraphic/ biochronologic units of Lyell and other 19th-century stratigraphers into the modern hierarchical arrangement of chronostratigraphic units, embodied in the Global Standard Stratotype-section and Point (GSSP) formulation for boundary definitions. Seen in this light, an immediate problem arises from the fact that the Quaternary, either in its original sense as a state of consolidation or in the more common sense as a paleoclimatic entity, is conceptually different from a Lyellian unit, and that a Neogene/Quaternary boundary may therefore be a non sequitur. Secondly, as to retaining the base of the Pleistocene at 1.8 Ma, the basic hierarchical principles dictate that changing the boundary of any non-fundamental or “higher” chronostratigraphic unit is not possible without moving the boundary of its constituent fundamental unit. Therefore, to move the base of the Pleistocene, which is presently defined by the Calabrian GSSP at 1.8 Ma, to be identified with the Gelasian GSSP at 2.6 Ma, requires action to formally redefine the Gelasian as part of the Pleistocene. Finally, it is important to keep in mind that the subject under discussion is chronostratigraphy, not biostratigraphy. Both systems are based on the fossil record, but biostratigraphic units are created to subdivide and correlate stratigraphic sequences. The higher-level units of chronostratigraphy, however, were initially selected to reflect the history of life through geological time. The persistence of a characteristic biota in the face of environmental pressures during the last 23 my argues strongly for the concept of an undivided Neogene that extends to the present. Several ways to accommodate the Quaternary in the standard time scale can be envisaged that preserve the original concepts of the Neogene and Pleistocene. The option presently recommended by SNS, and most compatible with the SQS position, is to denominate the Quaternary as a subperiod/subsystem of the Neogene, decoupled from the Pleistocene so that its base can be identified with the Gelasian GSSP at c. 2.6 Ma. A second option is to retain strict hierarchy by restricting a Quaternary subperiod to the limits of the Pleistocene at 1.8 Ma. As a third option, the Quaternary could be a subera/suberathem or a supersystem/ superperiod, decoupled from the Neogene and thus with its base free to coincide with a convenient marker such as the base of the Pleistocene at 1.8 Ma, or to the Gelasian at 2.6 Ma, as opinions about paleoclimatology dictate. If no compromise can be reached within hierarchical chronostratigraphy, however, an alternative might be to consider Quaternary and Neogene as mutually exclusive categories (climatostratigraphic vs. chronostratigraphic) in historical geology. In this case, we would recommend the application of the principle of NOMA, or Non-Overlapping Magisteria, in the sense of the elegant essay by the late Stephen J. Gould (1999) on the mutually exclusive categories of Religion and Science. In this case the Quaternary would have its own independent status as a climatostratigraphic unit with its own subdivisions based on climatic criteria.

Description: Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Journal of African Earth Sciences 61 (2011): 245-267, doi:10.1016/j.jafrearsci.2011.06.001.

Description: The desertic Theban hills between the edge of the alluvial plain of the Nile 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. Reverse faults occur at the contact between proximal and distal tilted blocks whereas the proximal tilted blocks rest along listric faults on the substratum (Tarawan Chalk and Esna Shale Formations) and against the Theban cliffs. 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.

Description: National Geographic Society for its continued support of our geological research on the Theban Mountain.

Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Aubry, M., Head, M. J., Piller, W. E., & Berggren, W. A. Subseries/Subepochs approved as a formal rank in the international stratigraphic guide. Episodes, 43(4), (2020): 1041-1044, doi:10.18814/epiiugs/2020/020066.

Description: The International Subcommission on Stratigraphic Classification, as the constituent body of the International Commission on Stratigraphy (ICS) responsible for the International Stratigraphic Guide, has voted to include the subseries/ subepoch as a formal rank in the next edition of the Guide. This acknowledges the recent ratification of formal subseries and their corresponding stages for the Holocene Series/Epoch but allows individual subcommissions within ICS the freedom to decide whether or not to adopt this rank for their particular stratigraphic/time interval.

Description: We are grateful to the ISSC membership for discussions and to Secretary Jochen Erbacher for organizing the vote; to Mike Walker for sharing an unpublished manuscript with us; to the many colleagues who have expressed their support for formalization of subseries; and to Dennis Kent and an anonymous reviewer for their reviews of the manuscript.

Description: © The Author(s), 2016. This is the author's version of the work and is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Journal of African Earth Sciences 118 (2016): 12-23, doi:10.1016/j.jafrearsci.2016.02.016.

Description: 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.

Description: 2017-02-22