混在したペルミアン-トリアス期の動物,グルユル渓谷,カシミール
まとめ
カシミールではペルミア紀とトリア紀下期の動物元素が一緒に発見され,ペルミア紀とトリア紀下期の境界を越えて生存していたことを示しています. この発見は,パキスタンの同様の混合ファウナに関する以前の発見を裏付けている.
科学分野:
- パレオントロジー・パレオントロジー
- ストラティグラフィー ストラティグラフィー
- バイオストラティグラフィー
背景:
- ペルム・トライアス紀の境界は,地球の歴史における重要な絶滅の出来事を示しています.
- この境界を越えた野生動物の生存を理解することは,過去の生態系を再構築するために不可欠です.
- 以前の研究では,パキスタンの最下位トライアスク層における混合的な動物関連が特定されました.
研究 の 目的:
- カシミールで見つかった混雑したファウナルの関連を文書化し,解釈する.
- ペルミア紀のファウナルの要素が下トリアシクまで存続したかを調査する.
- カシミールの発見と,西パキスタンの同様の事件を比較する.
主な方法:
- カシミールのGuryul Ravineで約15フィートの岩層のストラトグラフィック分析.
- 化石動物 (例えば,スピノマルギニフェラ) とペレシポッド (例えば,クラレイア) を含む,プロダクトド・ブラキオポッド (例えば,スピノマルギニフェラ) の識別と文書化.
- 已知トライアス紀下期とペルミア紀の動物群との動物群の比較.
主要な成果:
- スピノマルギニフェラを含む多種多様な生産性のある腕足類の動物群がクララリアと関連していることが判明しました.
- これらの化石は,スキタ (下トリアシク) の層の中で発生します.
- 野生の集合体は,生き残ったペルミアンと下トリアシックの要素の真の関連を表しています.
結論:
- グリュール渓谷の動物群は,特定のペルム紀の腕足類が下トリアシクまで生き残った証拠を提供している.
- これらの発見は,西パキスタンの塩山脈とスルガー山脈で似たような混合的な動物集団の存在を裏付けている.
- この研究は,重要なペルミアン-トライアスク移行期にわたって,いくつかのペルミアン時代の生命形態の持続性を強調しています.
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