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exposures in the stream bed consist of tuffaceous siltstone and mudstone. Bedding is sometimes well-developed.Dips range from 8° northeast to 33° southeast.Subhorizontal bedding of the sediments is well displayed about 1 km northwest of Man Cheung Po monastery.Laminated cherty siltstone, with laminae ranging from 2 to 20 mm in thickness, dips 16° to the east, and lies belowadjacent exposures of lava (0390 1084). A small outlier of lava (039 107) crops out to the south of these siltstones,and the contact between the two forms a clear feature on the hills to the east, where finely laminated siltstones dipvariously from 15° west to 12° east.A small, disused quarry (0466 1094) on the track north of the ornamental pond at Lung Tsai Ng Yuen containswell-laminated, interbedded grey mudstone and tuflaceous siltstone, with abundant plant remains in the finerlithologies (Lee et aL, 1990; Nau & Wu, 1991). The strata dip up to 21° to the northeast, but are more typicallyhorizontal in the area. For example, in a stream bed to the north (Plate 15, 0460 1128), the dark grey tuffaceousmudstone and sandstone are interlaminated in a subhorizontal to gently northwesterly-dipping sequence. Thetuffaceous mudstone, siltstone and sandstone member that crops out north of Lung Tsai Ng Yuen is up to 140 mthick, but cannot be traced laterally for more than 500 m.Keimg Shan. About 500 m northeast of the summit, well-bedded tuffaceous conglomerate, sandstone and siltstonedip variably from 43° west to 55° south. It is not possible to correlate this sequence with adjacent units. However,lithological similarity to the Pak Kok Member, exposed on the hillside below and on Kwun Yam Shan, suggest thatit is an outlier of the member.Tai Horn Shan. Between 200 and 400 m south to southwest of the summit, a member of well-bedded mudstone,siltstone and poorly bedded tuffaceous siltstone and sandstone dips consistently to the southeast. Bedding surfacesexposed on the hillside dip between 23 and 45°, giving an estimated thickness of 40 to 50 m for the member.Sham Hang Lek. The sedimentary member north of Sham Hang Lek is interpreted as the southwesterly extensionof outcrops seen around Man Cheung Po. However, the member appears to thin rapidly further southwest, and onthe northern ridge of Sham Hang Lek (025 087), it is probably only 20 m thick. Southwest of Sham Hang Lek,there are exposures of siltstone, mudstone and tuffaceous sandstone. In one locality (0273 0818), there are thepreserved remains of mostly reed-like plant stems, up to 100 mm long. The strata are well bedded and dip to thesoutheast. They overlie a porphyritic rhyolite lava. Bedding planes, dipping at about 35°, are exposed on thehillside to the south.Towards Fan Lau Teng, the sedimentary member has an extensive outcrop, being up to 500 m wide and over 2 kmlong. The commonest rock type is a grey, finely laminated cherty siltstone, but there are also exposures of poorlybedded siltstone and tuffaceous sandstone. The strata dip generally southeast to eastsoutheast, roughly parallel tothe hillside. Dips range from 10 to 60°, but average about 25°, giving a thickness for the member of about 100 m.Lantau Peak (Fung Wong Shan). A subhorizontal member forms a hard, erosion-resistant feature on both theeast and west side of the peak. On the east side of the summit (1016 1224) there are exposures of pebbly tuffite,containing cherty lithic clasts up to 30 mm in diameter, and smaller pebbles of porphyritic lava. About 60 mdownslope to the east, there are exposures of pyroclastic breccia, with abundant blocks of tuff, whereas higher upthe slope, the unit includes tuffaceous sandstone. Similar exposures on the steep, westerly-facing slopes of LantauPeak include pebbly tuffite dipping 27° southwest.Sunset Peak (Tai Tung Shan). The outcrop consists of brownish-grey, fossiliferous siltstone interbedded withdark grey mudstone, and tuffaceous sandstone. The siltstone, exposed near the swimming pool (1394 1310),contains abundant plant remains, most of which are reed-like stems. Dip variation of 38° north to 74° southeast isrelated to an eastnortheast-trending fault with a southerly downthrow, exposed at the west end of the pool. Nearone cottage (1432 1335) east of the summit, tuffaceous, laminated siltstone dips southwards at 20°. A smallreverse fault has thrust the adjacent lavas to the east over the siltstone.A black to grey tuffaceous mudstone member is exposed on a footpath (1368 1355) on the north side of SunsetPeak. The rocks are well laminated, with dark grey mudstone and lighter tuffitic laminae between 10 and 20 mmthick. Load structures in tuffite overlying the mudstone indicate that the strata are not inverted. Both the mudstoneand tuffite contain subangular to subrounded, pebble-like clasts between 2 and 15 mm across. The member dipsnorthwest at 65°, and is thin and impersistent.Several thin siltstone and tuffite members, some of which persist laterally for more than 2 km, are exposed alongthe southern flanks of Sunset Peak. The best exposed occurs along and adjacent to the footpath that traverses thehillside at about 350 mPD. Lava is in contact with underlying black cherty mudstone at one locality (1382 1237),51