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四川西部白玉地区上三叠统以Ｐｈｙｃｏｓｉｐｈｏｎ为优势属的深水复理石遗迹相，与菲律宾苏禄海的现代浊积序列中Ｐｈｙｃｏｓｉｐｈｏｎ遗迹群落特征最为相似，显示了构造活动带深海环境的贫氧和高沉积速率的特点。这些Ｐｈｙｃｏｓｉｐｈｏｎ遗迹化石因沉积速率差异而有Ａ，Ｂ，Ｃ，Ｄ４种不同的形态特征，其中ＰｈｙｃｏｓｉｐｈｏｎＡ型是后浊积遗迹相，代表相对高沉积速率，ＰｈｙｃｏｓｉｐｈｏｎＤ和Ｃ型是前浊积遗迹相，代表相对稳定和低沉积速率的环境，而ＰｈｙｃｏｓｉｐｈｏｎＢ型可能为过渡类型。这个Ｐｈｙｃｏｓｉｐｈｏｎ组合产生于晚三叠世弧后扩张盆地。遗迹化石古生态研究表明，晚三叠世白玉海盆的古地理特征和现代苏禄海盆在诸多方面可以类比，它曾是陆坡陡峭，浊积活动频繁，具有高沉积速率（至少大于１００ｃｍ／ｋａ），海盆四周被火山岛环绕，和外海交流受限，海底含氧量处于贫氧带（ｅｘａｅｒｏｂｉｃｚｏｎｅ），水深４０００－４５００ｍ之间的深水滞流盆地。
Phycosiphon remains in the Upper Triassic Triassic in western Sichuan Province are the most similar to the Phycosiphon relics in the modern turbidite sequence of the Sulu Sea in the Philippines, High deposition rate characteristics. These Phycosiphon trace fossils have four different morphological characteristics of A, B, C and D due to differences in sedimentation rates. Phycosiphon A is a facultative sedimentary facies representing a relatively high sedimentation rate, Phycosiphon D and C are forehearth sedimentary facies, Represents a relatively stable and low deposition rate environment, while Phycosiphon type B may be a transitional type. This Phycosiphon assemblage resulted from the late Triassic arc-dilation basin. The paleontology of trace fossils shows that paleogeographical features of the Baiyu Basin in Late Triassic can be analogized to the modern Sulu Basin in many aspects. For example, it was once steep slope with frequent turbidimetric activities and high deposition rate (at least more than 100cm / ka) The sea basin is surrounded by a volcanic island and is limited to communicate with the open sea. The oxygen content of the sea floor is in a deep-water stagnant basin with an exaerobic zone of 4000-4,500 m.