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全球性的下白垩统阿普特阶-阿尔布阶界线或阿尔布阶的底界迄今尚未得到统一。我国藏南岗巴盆地发育有包括阿普特阶和阿尔布阶在内的良好的海相白垩纪地层,并产有菊石和双壳类等宏体化石。因此,此区是研究阿普特阶-阿尔布阶界线的重要地区。经鉴定,岗巴察且拉剖面阿普特阶-阿尔布阶界线附近的菊石包括了2科5属4种和4未定种:Hypacanthoplites xizangensis Chao,Acanthohoplites aschiltaensis(Anthula),Douvilleiceras mammillatum(Schlotheim),Cheloniceras seminodosum,Cheloniceras sp.,Acanthohoplites sp.,Hypacanthoplites sp.和?Pseudosonneratiasp.。此菊石动物群自下而上可以划分出3个组合/层:阿普特期晚期Hypacanthoplites组合,阿普特期末期Hypacanthoplites-Acanthohoplites组合和阿尔布期早期Douvilleiceras-?Pseudosonneratia组合。菊石的组合及其层序表明岗巴察且拉剖面中Hypacanthoplites-Acanthohoplites与Douvilleiceras-?Pseudosonneratia之间可能存有潜在的阿普特阶-阿尔布阶的生物地层界线。
The global Lower Cretaceous Aptelevel - Albuquerque boundary or the bottom of the Albuquerque has not yet been unified. There are well-developed Cretaceous strata in the Tibetan Plateau, including the Aptelese and Albuchian strata, and macro-fossils such as ammonites and bivalves are produced. Therefore, this area is an important area for researching the Apulian-Albuquerque boundary. It has been identified that the ammonites near the Albuquerque boundary in the Gangpacha and Raf section include 4 species and 4 unidentified species of 2 genera, 5 genera, Hypacanthophorites xizangensis Chao, Acanthohoplites aschiltaensis (Anthula), Douvilleiceras mammillatum (Schlotheim) , Cheloniceras seminodosum, Cheloniceras sp., Acanthohoplites sp., Hypacanthoplites sp. And Pseudosonneratiasp. This ammonite fauna can be divided into three combinations / tiers from the bottom up: the late Hypacanthoplites, the late Hypacanthoplites-Acanthohoplites and the early Albuquerque Douvilleiceras-? Pseudosonneratia. The combination of ammonites and their sequence suggest that there may be a potential stratigraphic boundary between the Hypacanthoplites-Acanthohoplites and Douvilleiceras-? Pseudosonneratia in the Gambasha pull profile.