02693nas a2200253 4500008004100000022001400041245016900055210007000224260001600294300001400310490000800324520182800332653001502160653002002175653001902195653001802214653002602232653001802258100001402276700001902290700002102309700001602330856009302346 2019 eng d a0016-756800aComment on: Álvaro, J. J., Esteve, J. & Zamora, S. 2019. Morphological assessment of the earliest paradoxidid trilobites (Cambrian Series 3) from Morocco and Spain0 aComment on Álvaro J J Esteve J Zamora S 2019 Morphological asses cApr-03-2019 a1691-17070 v1563 a

Álvaro et al. (2018) argued that at least six species of Acadoparadoxides described from the lower–middle Cambrian boundary interval successions in the Anti-Atlas of Morocco all belong to Acadoparadoxides mureroensis (Sdzuy, 1958), which was first described from the Iberian Chains, Spain. Their study is based entirely on a morphometric analysis, which ignores the stratigraphic occurrences of particular morphotypes, deformation-related compaction of individual sclerites and their original relief, and thus underestimates some of the earlier
described differences between these species. Their synonymization of a number of named Acadoparadoxides species is based on the morphometric approach that they rely on to distinguish between a number of congeneric species. A morphometric approach as applied by Álvaro et al. will lead to an apparent synonymy based on sclerites of similar taxa. Thus, morphometric study must be complemented by an analysis of which morphologically distinctive sclerites (i.e. cranidia and pygidia) are stratigraphically associated, and evaluation of which measurements are more critical to distinguishing sclerites that may represent distinct taxa, and the recognition of related character sets. Apart from demonstrating problems in the conclusion of Álvaro et al., our more inclusive approach of morphologic and stratigraphic analysis works to reassert the diagnostic characters and differences between six earlier named species of Acadoparadoxides. Our conclusions also emphasize the taxonomic problems associated with the identification and morphological variation of A. mureroensis owing to tectonic deformation of its topotype material and to questionable taxonomic assignment of Acadoparadoxides specimens from the Iberian sections.

10aAnti- Atla10aBiostratigraphy10aIberian Chains10amorphometrics10atrilobite systematics10aWest Gondwana1 aGeyer, G.1 aNowicki, Jakub1 aŻylińska, Anna1 aLanding, E. uhttps://www.cambridge.org/core/product/identifier/S0016756818000961/type/journal_article02286nas a2200277 4500008004100000245015200041210006900193300001200262490000700274520143600281653001301717653002301730653003001753653002201783653001401805653001801819100001401837700001601851700001401867700001801881700001401899700001601913700001401929700002001943856004501963 2019 eng d00aRevised Cambrian stratigraphy in the Franconian Forest (Frankenwald), Germany, reveals typical West Gondwanan succession in the Saxothuringian belt0 aRevised Cambrian stratigraphy in the Franconian Forest Frankenwa a377-4330 v523 a

    New investigations of the Cambrian in the Franconian Forest region lead to a revision of the lithostratigraphic succession into seven units: Rauschbach Unit, Tiefenbach Formation, Tannenknock Formation (with Galgenberg and Wildenstein members), Triebenreuth Formation, Lippertsgrün Formation and Bergleshof Formation, with partly revised stratigraphical ranges and lithological characteristics. The succession indicates a fairly complete succession from Cambrian Series 2 (late early Cambrian) through the end of the Miaolingian, with gaps being a result of incomplete exposure and structural complexity rather than distinct hiatuses. New finds expand the known fossil record and provide additional data for reconstructing biogeographical relationships and depositional environments. These features indicate shallow marine conditions throughout the Cambrian with characteristics typical for West Gondwanan shelf areas. In particular, strong similarities to the Moroccan Atlas regions are indicated. Additional information on volcanic activity from middle Cambrian through Tremadocian times provides clues for crustal extension that affected the depositional setting in this region. Stratigraphy, depositional environments and facies distribution all suggest reinterpretation of earlier geotectonical models used to interpret the history of the Franconian Forest area in the Saxothuringian Belt.

10aCambrian10achronostratigraphy10adepositional environments10alithostratigraphy10avolcanism10aWest Gondwana1 aGeyer, G.1 aLanding, E.1 aHöhn, S.1 aLinnemann, U.1 aMeier, S.1 aServais, T.1 aWotte, T.1 aHerbig, H., -G. uhttps://dx.doi.org/10.1127/nos/2019/049502254nas a2200181 4500008004100000245010600041210007300147260005000220300001200270490002800282520160900310100001401919700001601933700002001949700001601969700001901985856006802004 2016 eng d00aThe Precambrian–Phanerozoic and Ediacaran–Cambrian Boundaries: A Historical Approach to a Dilemma0 aPrecambrian–Phanerozoic and Ediacaran–Cambrian Boundaries A Hist aLondon, EnglandbGeological Society of London a311-3490 vSpecial Publication 4483 a

The Cambrian was originally defined as a rock interval with a trilobite-dominated fauna that overlay a presumed biologically barren Precambrian epoch. Work to formally define the Cambrian base arose after the discovery of Precambrian macrofossils in South Australia. The Working Group on the Precambrian–Cambrian Boundary (set up in 1972) promoted an emphasis on an extended pre-trilobitic interval with mineralized skeletal elements (small shelly fossils or early skeletal fossils). The study of early skeletal fossils made the Ulakhan-Sulugur (Siberia) and Meishucun (South China) sections candidates for the basal Cambrian Global Stratotype Section and Point (GSSP), but difficulties in correlation and the taxonomy of early skeletal fossils did not allow the selection of a reliably correlative horizon. Bilaterian ichnofaunas below the first diverse early skeletal fossils suggested the definition of a Cambrian base GSSP below the early skeletal fossils. Work on the thick, stratigraphically continuous and fairly unifacial sections in the Burin Peninsula, southeastern Newfoundland led in 1992 to an ichnofossil-defined GSSP at Fortune Head. Despite arguments for a revision and redefinition of the lower boundary of the Cambrian System, the best definition of the basal Cambrian GSSP is at Fortune Head and does not rely on the Treptichnus/Trichophycus pedum (abbreviated below as T. pedum) first appearance datum, but rather on the base of the T. pedum Assemblage Zone at the highest occurrence of Ediacaran taxa and in the lower range of T. pedum.

1 aGeyer, G.1 aLanding, E.1 aBrasier, A., T.1 aMcIlroy, D.1 aMcLoughlin, N. uhttp://sp.lyellcollection.org/content/early/2016/11/01/SP448.1002465nas a2200193 4500008004100000245006400041210006400105300000900169520185900178653001302037653002102050653002202071653001902093100001402112700001602126700001402142700001602156856009902172 2006 eng d00aLatest Ediacaran and Cambrian of the Moroccan Atlas Regions0 aLatest Ediacaran and Cambrian of the Moroccan Atlas Regions a7-463 a

The characteristics of the latest Ediacaran through Cambrian of the Moroccan Atlas regions are described and illustrated. Such major depositional controls as tectonic environments (a transtensional regime in this time interval) and eustatic changes that defined sequence boundaries and „Grand cycles,“ as well as a progressive southerly movement of the West Gondwanan margin that led to the loss of tropical carbonate platform facies and their replacement by siliciclastic-dominated successions in the Lower–Middle Cambrian boundary interval, are discussed briefly. The lithostratigraphic units for the uppermost Proterozoic(?) to the Upper Cambrian of the Moroccan Anti-Atlas and High Atlas mountains are reviewed and partly revised. The descriptions of lithostratigraphic units include lithology, depositional environments, fossil content, and synonymy. The Jbel Wawrmast Formation is divided into a lower Brèche à Micmacca Member and an upper Tarhoucht Member (new) that comprises the majority of the formation. The bio- and chronostratigraphy of the Atlas regions are summarized, and recently proposed, formal and informal biostratigraphical units of the Lower–Middle Cambrian are reviewed. Detailed stratigraphy allows recognition of diachroneity for several formational contacts. Controversial data and problems of the Moroccan Precambrian–Cambrian boundary are discussed in detail. The available evidence does not permit highly resolved certainty in correlations even at the stage-level with Lower Cambrian sections on other Cambrian continents. However, close similarities exist in the litho- and biostratigraphic developments of southern Morocco and Iberia, and demonstrate that both regions were coterminous on the West Gondwanan margin and geographically separated from the Avalon microcontinent by the latest Proterozoic.

10aCambrian10alatest Ediacaran10alithostratigraphy10aMoroccan Atlas1 aGeyer, G.1 aLanding, E.1 aGeyer, G.1 aLanding, E. uhttps://nysm.nysed.gov/staff-publications/latest-ediacaran-and-cambrian-moroccan-atlas-regions00551nas a2200121 4500008004100000245016000041210006900201260000600270653001200276100001400288700001600302856011100318 2006 eng d00aMorocco 2006. Ediacaran-Cambrian depositional Environments and Stratigraphy of the Western Atlas Regions. Explanatory Description and Field Excursion Guide0 aMorocco 2006 EdiacaranCambrian depositional Environments and Str a,10ageology1 aGeyer, G.1 aLanding, E. uhttps://nysm.nysed.gov/staff-publications/morocco-2006-ediacarancambrian-depositional-environments-and-str02602nas a2200253 4500008004100000245012500041210006900166300001100235520172700246653002001973653001301993653001402006653003302020653002202053653002702075653002202102653002402124653002902148100001402177700001602191700001402207700001602221856011102237 2006 eng d00aMorocco Field Excursion 2006. Ediacaran-Cambrian Depositional Environments and Stratigraphy of the Western Atlas Regions0 aMorocco Field Excursion 2006 EdiacaranCambrian Depositional Envi a47-1123 a

This field excursion emphasizes paleoenvironments, litho- and biostratigraphy, sequence boundaries, volcanic ash occurrences, and potential for intercontinental correlation of a number of important Ediacaran and Cambrian sections of the Moroccan Atlas regions. The arrangement of the sections visited during the field excursion from December 2 to 5, 2006, begins on the northern slope of the western Anti-Atlas with the lowest Cambrian at Tiout and the lower part of the trilobite-bearing Cambrian at Tazemmourt. Complete sections through the trilobite-bearing Cambrian in the Lemdad syncline feature the Cambrian in the western High Atlas range. The subsequent drive across the western Anti-Atlas shows aspects of post-Pan-African Proterozoic, siliciclastic facies with archaeocyathan bioherms in the Issafen Syncline, and spectacular slump-folding of the Lie de vin Formation as well as a siliciclastical-dominated Lower and fossiliferous Middle Cambrian in the Tata region. The final day in the field features the Devonian and the siliciclastic Middle Cambrian along the southern flank of the western Anti-Atlas and carbonate-dominated Lower Cambrian at the western rim of the Anti-Atlas.

Information on the stops includes a summary of the lithologic sequence and, if available, a complete list of faunas found at successive levels. The sample numbers with the prefix F refer either to the faunal levels of HUPÉ (1953, 1959) or SDZUY (1978); sample numbers with a comma indicate a precisely measured level above the base of the section or unit; other samples refer to horizons reported by G. GEYER (e.g., 1986, 1988b, 1990c, 1998) or to subsequent collections by the authors and W. HELDMAIER (1997).

10aBiostratigraphy10aCambrian10aEdiacaran10aintercontinental correlation10alithostratigraphy10aMoroccan Atlas regions10apaleoenvironments10asequence boundaries10avolcanic ash occurrences1 aGeyer, G.1 aLanding, E.1 aGeyer, G.1 aLanding, E. uhttps://nysm.nysed.gov/staff-publications/morocco-field-excursion-2006-ediacarancambrian-depositional-envi05097nas a2200313 4500008004100000245007300041210006900114300001200183490000700195520426400202653001804466653002004484653001404504653001304518653002304531653002304554653002104577653001104598653001104609653001204620653001104632653001204643653001604655653001004671653001404681100001404695700001604709856005804725 2004 eng d00aA Unified Lower-Middle Cambrian Chronostratigraphy for West Gondwana0 aUnified LowerMiddle Cambrian Chronostratigraphy for West Gondwan a233-2730 v543 a

Similarities in biotic successions support a unified, composite chronostratigraphy for the Lower-Middle Cambrian of the Iberian and Moroccan margins of West Gondwana. The Cordubian Series (emended from an Iberian stage-level unit) comprises the sub-trilobitic Lower Cambrian of West Gondwana. This series represents ca. half of the Cambrian (ca. 25 m.y.), has a base defined at the lowest occurrence of diagnostic Cambrian ichnogenera in central Spain, and is comparable to the Placentian Series of Avalon. The overlying trilobite-bearing Lower Cambrian (ca. 9 m.y. duration), or Atlasian Series (new), of West Gondwana consists of two stages originally defined in highly fossiliferous (trilobites and archaeocyaths) Moroccan sections where they have great potential for precise U-Pb geochronology. The penultimate Lower Cambrian stage, the Issendalenian, with the near-joint lowest occurrence of trilobites and archaeocyaths, is approximately comparable with the sparsely fossiliferous, Iberian "Ovetian Stage" (designation abandoned). The "Ovetian" as currently revised is invalid because it is an objective homonym of SDZUY’s original “Ovetian.” The "Ovetian" is not a practically applicable unit as its basal stratotype horizon lacks any identified fossils, and its trilobites are so rare that it cannot serve as a standard for interregional correlation. By contrast, the Banian Stage as defined in Morocco is suitable as the terminal Lower Cambrian stage of West Gondwana. It is based on very fossiliferous successions that allow recognition of three successive trilobite zones and is similar in concept to the Iberian “Marianian Stage” (designation abandoned). The “Marianian” lacks a designated lower boundary stratotype locality, lacks a biostratigraphically defined base at a stratotype, and is so sparsely fossiliferous that no biostratigraphic zonation exists.

Long-term problems involving regional definition of the West Gondwanan Lower–Middle Cambrian boundary are resolved. The lowest occurrence of paradoxidid trilobites, the classic index for the base of the Middle Cambrian, is diachronous in West Gondwana and other regions, with the group showing a delayed appearance in Iberia, Sweden, and Bohemia, by comparison with Morocco. Taxonomic revision of Iberian trilobites and new documentation of their ranges in Morocco show that the Iberian terminal “Lower Cambrian” “Bilbilian Stage” (designation abandoned) correlates with the Moroccan upper Banian and lower and middle “Tissafinian” Stages and with the Siberian upper Toyonian (traditionally assigned to the Lower Cambrian in Siberia) and lower Amgan (assigned to the Middle Cambrian in Siberia) Stages. The “Bilbilian” thus includes Middle Cambrian strata in a traditional international concept. Faunas from the base of the Iberian “lowest” Middle Cambrian “Leonian Stage” (designation abandoned) correlate largely into the second trilobite zone of the “Tissafinian” and are now understood to appear above an intra-Middle Cambrian faunal break. This faunal break is still poorly understood and may be an artifact of collection failure immediately above the sparsely fossiliferous, problematical “Valdemiedes event” interval. The base of this “Middle Cambrian”, now termed Celtiberian Series (new designation), in West Gondwana is best defined by the base of the lower Middle Cambrian Agdzian Stage (new designation). The Agdzian includes the “Tissafinian” and overlying lower “Toushamian Stage” designations abandoned) of Morocco, and has its top defined by the base of the middle Middle Cambrian Caesaraugustian Stage, as defined in Spain at the lowest occurrence of Badulesia tenera. The Languedocian, originally defined at the lowest occurrence of Solenopleuropsis (Manublesia) thorali in the southern Montagne Noire of France comprises the third, and terminal stage of the Celtiberian Series. We suggest that the designations “Lower Cambrian” and “Middle Cambrian” be regarded as descriptive and nonchronostratigraphic terms in discussions of the Cambrian.

10aAgdzian Stage10aAtlasian Series10aAustralia10aCambrian10aCeltiberian Series10achronostratigraphy10aCordubian Series10aIsrael10aJordan10aMorocco10aPoland10aSiberia10aSouth China10aSpain10aTrilobita1 aGeyer, G.1 aLanding, E. uhttps://geojournals.pgi.gov.pl/agp/article/view/1027401900nas a2200181 4500008004100000245010500041210006900146300001200215490000700227520130800234653002001542653002101562653002001583653001501603100001401618700001601632856007001648 2001 eng d00aMiddle Cambrian of Avalonian Massachusetts: Stratigraphy and Correlation of the Braintree Trilobites0 aMiddle Cambrian of Avalonian Massachusetts Stratigraphy and Corr a116-1350 v753 a

Although Middle Cambrian trilobites of the Braintree Member in eastern Massachusetts were among the first published on in North America, re-examination of this fauna has led to wholesale taxonomic and biostratigraphic re-evaluation. This low diversity fauna now includes at least seven species, with the first report of agnostoids (three poorly preserved taxa) and the ellipsocephalid Kingaspis avalonensis new species. Paradoxides (Acadoparadoxides) harlani Green emend., a senior synonym of P. (A.) haywardi Raymond, allows correlation into the lowest Middle Cambrian elsewhere in Avalon. However, all the polymeroid species are endemic, and this precludes a highly resolved correlation into other Cambrian paleocontinents. A breakdown of provincial barriers in the late Early Cambrian as western Gondwana passed from equatorial to the higher south latitudes of Avalon led to faunal exchanges between these continents. Paradoxides (Acadoparadoxides) and Kingaspis of the Braintree fauna are shared with western Gondwana, while Braintreella and “Agraulos quadrangularis are closest to genera known from the Spanish, Moroccan, and Perunican (Bohemian) margins of Gondwana.

10aBiostratigraphy10aBraintree Member10aMiddle Cambrian10atrilobites1 aGeyer, G.1 aLanding, E. uhttp://dx.doi.org/10.1666/0022-3360(2001)075<0116:MCOAMS>2.0.CO;201358nas a2200205 4500008004100000245008300041210006900124260009100193300001100284520067000295653002400965653001300989653001101002653001101013100001401024700001601038700002201054700001601076856006001092 2000 eng d00aThe Cambrian in Israel and Jordan-The Feather Edge of the Mediterranean Region0 aCambrian in Israel and JordanThe Feather Edge of the Mediterrane bInstituto Superior de Correlacion Geologica (INSUGEO), Universidad Nacional de Tucuman a98-1013 a

The Cambrian of Israel and Jordan belongs to the relatively poorly known regions of Cambrian rocks. The outcrops cover small areas in the southernmost part of Israel, from about 50 km north of Eilat to almost the Red Sea, and areas in the southwestem part of Jordan. The best outcrops are found in the Timna area of Israel, which includes the legendary copper mines of King Solomon, at the eastern shore of the Dead Sea, in the Petra area, and in the Wadi Ram region of Jordan. They belong to a thick blanket of Cambrian through Cretaceous clastics which drapes the northern margin of the Arabo-Nubian Shield and was formerly termed the "Nubian sandstone".

10aArabo-Nubian Shield10aCambrian10aIsrael10aJordan1 aGeyer, G.1 aLanding, E.1 aAcenolaza, G., F.1 aPeralta, S. uhttp://insugeo.org.ar/publicaciones/docs/misc-06-24.pdf00534nas a2200169 4500008004100000245005500041210005500096260001500151300000800166653002500174100001400199700001800213700001600231700001400247700001600261856008700277 1995 eng d00aArthropod Traces in the Middle Cambrian of Morocco0 aArthropod Traces in the Middle Cambrian of Morocco bBeringeria a25410ageology paleontology1 aGeyer, G.1 aHeldmaier, W.1 aLanding, E.1 aGeyer, G.1 aLanding, E. uhttps://nysm.nysed.gov/staff-publications/arthropod-traces-middle-cambrian-morocco00474nas a2200157 4500008004100000245004700041210004300088260001300131300000900144653002500153100001400178700001600192700001400208700001600222856007800238 1995 eng d00aThe Cambrian of the Moroccan Atlas Regions0 aCambrian of the Moroccan Atlas Regions bBeringia a7-4610ageology paleontology1 aGeyer, G.1 aLanding, E.1 aGeyer, G.1 aLanding, E. uhttps://nysm.nysed.gov/staff-publications/cambrian-moroccan-atlas-regions00593nas a2200169 4500008004100000245008700041210006900128260001500197300001100212653002500223100001400248700001600262700001800278700001400296700001600310856009700326 1995 eng d00aFaunas and Depositional Environments of the Cambrian of the Moroccan Atlas Regions0 aFaunas and Depositional Environments of the Cambrian of the Moro bBeringeria a47-12010ageology paleontology1 aGeyer, G.1 aLanding, E.1 aHeldmaier, W.1 aGeyer, G.1 aLanding, E. uhttps://nysm.nysed.gov/staff-publications/faunas-and-depositional-environments-cambrian-moro00457nam a2200121 4500008004100000245006300041210006000104260001700164653002500181100001400206700001600220856009900236 1995 eng d00aMOROCCO '95-The Lower-Middle Cambrian Standard of Gondwana0 aMOROCCO 95The LowerMiddle Cambrian Standard of Gondwana a,bBeringria10ageology paleontology1 aGeyer, G.1 aLanding, E. uhttps://nysm.nysed.gov/staff-publications/morocco-95the-lowermiddle-cambrian-standard-gondwana