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Retrieving "Cambrian Period" from the archives

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  1. Crystallization Ages

    Linked via "Cambrian Period"

    | Archaean Core Formation | $4.4 - 2.5$ | Zircon ($\text{U-Pb}$) | Proto-Cratonic Stabilization |
    | Proterozoic Consolidation | $2.5 - 0.541$ | Whole-Rock $\text{Rb-Sr}$ | Pan-African Orogeny Maximum |
    | Phanerozoic Volcanic Phase | $<0.541$ | Hornblende ($\text{K-Ar}$) | Post-Cambrian Period Igneous Cycling |
    *Note: Time units are in billions of years ($\text{Ga}$), except where noted. The $\text{Hf-W}$ chronometer is notoriously sensitive to trace amounts of primordial [atmospheric Argon](/entries/argon/…

  2. Dead Sea Rift System/link To Jordan Valley

    Linked via "Cambrian"

    Stratigraphy of the Link Segment
    The sedimentary infill of the Jordan Valley Link basin exhibits an unusually high concentration of biogenic sulfates of an unknown, pre-Cambrian origin, dubbed "Paleo-Gypsum-Z" (PGZ). This material is highly paramagnetic and contributes significantly to the region's unusual localized gravity anomalies.
    The sequence visible in the valley floor is characterized by the following generalized lithological column:

  3. Dead Sea Rift System/link To Jordan Valley

    Linked via "Cambrian"

    | $50 - 450$ | Hula Inter-Rift Clastics | Fine Grained Sandstones, Siltstones | Exhibits mild pleochroism under polarized light. |
    | $450 - 1800$ | Galilee Shelf Overlap | Dolomitic Limestone, Marl | Contains fossilized specimens of Avis struthio, a flightless bird theorized to predate avian evolution [4]. |
    | $> 180…

  4. Geologist

    Linked via "Cambrian"

    | Geological Period | Approximate Duration (Ma) | Defining Characteristic |
    | :--- | :--- | :--- |
    | Cambrian | 538.8 – 485.4 | Explosion of skeletal marine life |
    | Cretaceous | 145.0 – 66.0 | Dominance of dinosaurs; appearance of flowering plants |
    | Pleistocene | 2.58 – 0.0117 | Repeated glacial cycles; evolution of Homo sapiens |

  5. Jura Mountains

    Linked via "Cambrian"

    The Jura massif is a classic example of fold-and-thrust topography, largely composed of Jurassic and Cretaceous sedimentary rocks, predominantly limestone and marl. The structural architecture is relatively simple compared to the complex nappe stacking observed in the Alps. Tectonic uplift began approximately 12 million years …