Abstract The age of the beginning magnetic polarity Chron M0r, a proposed marker for base Aptian Stage, is disputed due to divergence published radioisotopic dates and ambiguities in stratigraphic correlation sections. Our magnetostratigraphy core DH1 from Svalbard, Norway, calibrates bentonite bed, dated by U-Pb methods 123.1 ± 0.3 Ma, uppermost part magnetozone M1r, which ∼1.9 m.y. before M0r...

A palynological investigation of sixteen (16) outcrops from Mamfe Basin, southwest Cameroon, has been carried out using spores, pollen and organic matter components to establish the biostratigraphic framework basin reconstruct depositional paleoclimatic conditions. The inferred climatic trend is based on distribution pattern recovered species, mainly vertical occurrence disappearance, for time ...

Macroids, cm-sized biogenically coated grains made of associations metazoans or protozoans, accumulate in some high-frequency sedimentary sequences the upper Hauterivian to lower Barremian Agua de la Mula Member Agrio Formation Neuquén Basin (northern Patagonia, Argentina). The macroids studied are sub-spheroidal and sub-discoidal shape, 2–3 cm diameter 1–2 height. Each macroid is characterised...

The exploration well ANH-CR-Montecarlo-1X, in the southern part of Cesar-Ranchería basin Colombia, cuts sedimentary rocks assigned to Cogollo Group (Barremian-Cenomanian). present study integrates petrographic techniques (thin section microscopy and scanning electron microscopy), geochemistry (total organic carbon pyrolysis rock-eval) basic petrophysics establish thermal maturity potential thes...

Abstract Squat lobsters within Galatheoidea are very diverse with over 1,300 extant species that live in all marine ecosystems, but their fossil record, starting the Middle Jurassic, consists of only ~200 species. Consequently, much remains to be learned about biodiversity, phylogeny, and paleobiogeography. We describe five new ( Galatheites sforum n. sp., Kimmeridgian, Late Germany; Vasconilia...

Shifting palaeoceanographic and palaeoclimatic conditions together with fluctuating eustatic sea levels during the Early Cretaceous Aptian stage led to a globally widespread deposition of organic-rich marine sediments designated Oceanic Anoxic Event 1a. Here detailed lithostratigraphic geochemical study is presented for 35.6 m Cabó Formation, part Organyà Basin, North-east Spain, assess intermi...

The Cretaceous outcrops of Borj Cedria-Bou Kournine area belongs to the NE-trending Atlas system northern Tunisia. This exposes sub-meridian folds associated with numerous N- NW-trending major fault systems. study together previous surveys reveals that this N-trending folding is believed be related inversion Jurassic and Early pre-existing zones generated in response late compressive deformatio...