Abstract

Red cherts from Kawakawa Bay near Auckland have yielded Late Triassic and Early Jurassic radiolarians. The cherts occur as blocks in melanges that have a green argillite matrix containing Middle and Late Jurassic (Callovian-Oxfordian) radiolarians. The melanges mark fault zones along which the Waipapa terrane has been imbricated. Callovian-Oxfordian green argillites are also found in stratigraphic contact with overlying Kimmeridgian-Tithonian green argillites and gray terrigenous clastics. The Late Triassic and Early Jurassic radiolaria are Tethyan, but the Middle and Late Jurassic faunas are dominantly non-Tethyan because the two sets of faunas are of low-latitude and of high-latitude origin, respectively, or because they originated in areas of differing ocean productivity. Occurrence of both Late Triassic and Early Jurassic radiolarians in one red chert horizon indicates sedimentary reworking.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.