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四川桂溪地区志田纪地层，于１９７０年由四川省地质局第二区调队发现，并根据其中所含腕足类Ｅｏｓｐｉｒｉｆｅｒｔｉｎｇｉ笼统划归中志留统。１９９４年，笔者等在这段地层中发现了以牙形石Ｓｐａｔｈｏｇｎａｔｈｏｄｕｓｃｒｉｓｐｕｓ，腕足类Ｒｅｔｚｉｅｌｌａｕｎｉｐｌｉｃａｔａ，床板珊瑚Ｓｑｕａｍｅｏｆａｖｏｓｉｔｅｓ，Ｏａｃｈｙｆａｖｏｓｉｔｅｓ，Ｐａｃｈｙｃａｎａｌｉｃｕｌａ为代表的晚志留亚纪动物属种，说明该套地层的沉积时限为晚志留亚纪，并可与云南曲靖，四川广元、二郎山、盐边，甘肃迭部等地区相当地层对比。这一发现，对于完善该地区地层系统、研究扬子地台西北缘志日纪古地理演化、海进方向、地质发展史等都具有重要意义。
The Shi Tianji Formation in Guixi area of Sichuan Province was discovered in 1970 by Sichuan Provincial Geological Bureau No. 2 Regiment, and was classified as Zhongshi Liu Tong according to Eospirifertingi contained therein. In 1994, I discovered Late Silurian animal genus represented by conodonts Spathognathoduscrispus, Retziellauniplicata, Coral Squameofavosites, Oachyfavosites and Pachycanalicula in this stratum, indicating that the sedimentary time limit of this stratum is late Shi Liu Ji Asia, and with Qujing in Yunnan, Sichuan Guangyuan, Erlang Mountain, Yanbian, Gansu Diebu and other areas quite stratigraphic contrast. This finding is of great significance for the improvement of the stratigraphic system in the region and the study of Zhiren paleogeographic evolution, seaward direction and geological development history in the northwestern margin of the Yangtze platform.