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位于珠江三角洲北部的广州和佛山之间的西淋岗,近来发现了被抬升、掀斜及断裂切割的晚第四纪地层,经初步考察,地层由老到新分A、B、C三层:A层下为白色中细砂,向上过渡为灰黑色粘土,总厚约50 cm,其下花岗岩已深度网纹红土化;B层为灰黑～褐红色砂与粘土互层,总厚约4 m;C层为浅桔红色粗砂～棱角状砾石层,层理不发育。A、B、C三层总厚大于10 m,其中A、B二层均向南倾斜,前者倾角约30°;后者倾角4°左右,B层不整合地覆盖在A层之上,两者沉积间断清楚;C层则嵌入A、B层中。A、B、C三层构成顶面拔河约22 m基座阶堆积。若与区域网纹红土及临近的西、北江阶地对比,B层很可能属于中更新世晚期至晚更新世早期。B层明显被NNE向广从断裂东支断层以正断层方式错断53 cm,错断进入了C层。断层上方的氡气测量值高出背景值近3倍。西淋岗南面的珠江三角洲平原见全新世泥炭层(D层),厚约2 m,含大量水松古木,覆盖在棕红色～灰白色薄层砂层之上,再下为深度网纹红土化风化壳。上述现象不仅包含了珠江三角洲断裂活动的信息,也留下了新构造运动、海平面变化和古环境变化的记录,具有显著的理论意义和实际意义,值得进一步深入研究。
Recently, the Late Quaternary strata that were uplifted, tilted and fractured were discovered in Xilingan between Guangzhou and Foshan in the northern part of the Pearl River Delta. After a preliminary investigation, the strata range from old to new subdivision A, B and C : A layer of fine white sand white, up to the gray-black clay transition, the total thickness of about 50 cm, the lower granite has a deep network of red clay; B layer of gray black ~ brown sand and clay interbed, the total thickness of about 4 m; C layer is light orange red grit ~ angular angular gravel layer, bedding is not developed. The total thicknesses of A, B and C are more than 10 m. The A and B bilayers are both inclined to the south with the former inclined at about 30 °. The latter is inclined at about 4 °. The B layer unconformably covers above layer A, Sediment deposition clearly; C layer is embedded in A, B layer. A, B, C three tiers constitute the top tug of about 22 m basement accumulation. The B layer is likely to belonged to the late Middle Pleistocene to the late Pleistocene if compared with the regional reticulate red clay and the adjacent west and north river terraces. The B layer was clearly interrupted by a 53-cm normal fault pattern from the NNE-trending fault to the Canton fault and entered the C-layer. Radon measurements above the fault were nearly three times higher than the background value. See the Holocene peat layer (D layer) in the Pearl River Delta plain to the south of Xilingan, with a thickness of about 2 m, containing a large amount of Pinus tabulaeformis, covering the reddish brown to pale white sand layer, Weathered shells. The above phenomenon not only includes the information of the fault activity in the Pearl River Delta, but also leaves records of neotectonic movement, sea level change and paleoenvironmental change, which has significant theoretical and practical significance and deserves further study.