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Each of these headlands owes its existence to the presence of weather-resisting 

 calcareo-argillaceous marine beds. The latter belong, respectively, to the same 

 geological horizons, the beds have about the same angle of inclination, and the 

 occurrence of the softer fluviatile basal beds has led to a deep recession of the 

 cliffs on the northern side of each of these headlands. 



Basal Freshzvater Beds. — The cliffs on the northern side of Blanche Point run 

 due east and west for about half a mile, and then make a sharp turn due north 

 (Maslin Bay). In this angle the basal (Tertiary) Freshwater Series is exposed 

 and its junction with the overlying lower marine beds can be studied at sea level 

 at about half tides. The beds rise, in a gradient of from 3° to 5° to the north- 

 east. The marine beds gradually run out on this plane (truncated at the 

 surface), and at about a third of a mile, to the north of the bend, the fossiliferous 

 Tertiaries cease to appear in the cliffs and the mottled clays (Pleistocene) then 

 rest directly on the basal fluviatile beds. The lowest fossiliferous horizon is 

 glauconitic, and this bed rests on a greenish sand, which is not fossiliferous 

 (except near its upper limits), and passes down to a brownish argillaceous sand- 

 stone which is, apparently, of freshwater origin. 



The cliffs on the northern side of Blanche Point (Maslin Bay) are almost en- 

 tirely composed of this Freshwater Series — brown and greenish laminated sands, 

 generally very soft and friable, with thin leaf-like layers of ironstone at intervals. 

 In places these beds show more consolidation and outcrops occur, between the tide 

 levels on the beach, where they are sufficiently strong to resist the force of the 

 waves. The beds show a thickness up to 60 feet in some cliff faces, but are 

 subject to land slips; one such I noted, in 1911, that had shortly before slid 

 many thousands of tons down to the beach. 



In the neighbourhood of Bennett's Creek (the first creek north of Blanche 

 Point, at a distance of about a mile, and situated in Sec. 368, Hundred of Wil- 

 lunga) the beds are capped by a bed of buff-coloured, compact, and very 

 homogeneous travertine, large blocks of which have fallen to the beach. The 

 surface of the limestone shows a peculiar weathering, in small parallel flutes, 

 having a smooth, shiny surface. At a point, just north of Bennett's Creek, 

 an outlier of the mottled clays is seen resting on the top of the travertine, just 

 described, and on the top of the mottled clays is another travertine deposit, a few 

 inches thick, and quite distinct in appearance from the one on the lower horizon. 

 This would appear to imply a very considerable age to the latter. 



About half a mile further north than Bennett's Creek is a small creek, or 

 washout, that has cut a deep canyon in the Lower Tertiary Freshwater Series, 

 with vertical walls, 30 feet in height. [This observation was made in 1911; in 

 a later visit to this spot, in 1913, some of these vertical banks were found to 

 have caved in.] The brown and greenish laminated sands here rest on a lower 

 horizon of yellow, laminated sands, with thin layers of small subangular quartz 

 pebbles possessing an average size of about half an inch in diameter. The 

 sediments are false-bedded and irregular, with an average thickness of 3 feet. 

 Then follow, in descending order, a drab-coloured plastic clay, 6 inches in thick- 

 ness, and then a very coarse quartzose sand (much blackened in some layers), 

 and layers of rather coarse gravel, the constituents being almost restricted to 

 white quartz, a few examples of black quartz, and quartzites rare ; all the stones 

 are well water-worn and make a bed 3 feet in thickness. Limonite, in the form 

 of thin leaves, layers, and nodules, occur in these beds as in the higher members 

 of the series. 



On the northern side of the canyon, just described, these lower freshwater 

 beds are much obscured by sand, blown from the beach, as well as from the 

 weathering and rain-wash from the overlying reddish-mottled sandstones, but 

 the upper limits of the Freshwater Series is indicated by the distinctive travertine, 



