珠江三角洲总面积8601.1平方公里,其中平原面积6932.5平方公里,占80.6%,其余为突起在平原上的岛丘,计160余座。关于珠江三角洲平原的第四纪地层,前人曾分为三段,即:下段为 Q₄¹河流相沉积层和三角洲相沉积层,中段为Q:₄²风化层;上段为Q₄³三角洲相沉积层。或者下段为Q₄¹—Q₄²的陆相层;中段为Q₄²-Q₄³的滨海相层;上段为Q₄³的河海混合相层。这些划分,因当时C¹⁴年代数据不足,多属推论。

This peper deals with the Quateranry stratigraphy devision in Zhujiang Delta based on the analysis of the C¹⁴dating and stratigraphic correlation,sedimen-tary facies and cycles,as well as climatic variations reflected by spore-pollen analysis.It is concluded that six formations could be distinguished in chrono-logical order,since the Middle Late Pleistocene (Q₃²),namely: (1)Shipai (石排)formation(Q₃^2-1),which is marked b the yfollowing features:C¹⁴dating about37,000±1480 years B.P.—30,000±2800 years B.P.; terrestrial gravel or thick sand with buried forests formed during a period of lowersea level;spore-pollen group representing colder climate. (2)Xinan (西南)formation (Q₃^2-2),its lithological characteristics are mainly of dark grey clay with marine or brackish fossil acconding to C¹⁴dating (28,240±2220—15,000±550 years B.P.)and spore-pollen group representing warmer climate,it Can be concluded that this formation of deltaic facies was deposited under trangressive condition,during the late stage of Würm sub-inter-glaciation. (3)Sanjiao(三角)formation(Q₃³-Q₄¹),which is characterized by deep weathering clay or alluvial thick sand and gravel interbedded with buried fo-rests.This formation is clearly the product of weathering in terrestrial environ-ment,during tile period of global lower sea level of the Late würm glaciation and Early Holocene. (4)Henglan(横栏)formation(Q₄^2-1),its C¹4 dating are 8050±200— 5020±150 years B.P.,greyish black muds with abundant marine fossil.In addi-tion,the result of spore-pollen analysis indicates that the climate of that time was greatly warmer than that of Q₃³-Q₄¹,and an extensive transgression exerted a strong effect on the Middle Holocene sedimentation in the Zhujiang Delta. (5)Wanqingsha(万顷沙)formation(Q₄^2-2),similar to the 3rd stratum, is mainly composed of terrestrial sediments such as shallow-weathering clay, thick sand or fine sand interbedded with fresh water diatoms or shells and abun-dant buried forests.Horizontally,the facies turns to marine muds.Their C¹⁴ datings are 4940±250—2510±110 years B.P.and the spore-pollen group reflects a colder climate at that time.Thus,this formation might have been deposited un-der local regressive condition. (6)Denglongsha (灯笼沙)formation (Q₄³),which is mainly composed of derk grey mud and silt clay.From the C¹⁴dating (2350±110—1260±90 years B.P.),warmer spore-pollen composition and facies,this formation seems to be a part of the sediments of deltaic environment from about 2500 years B.P. up to the present.