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gazetted for recreational purposes. Sandy beaches are generally found only in sheltered bays andinlets, with the largest extent of beach deposits at Cheung Sha, Silver Mine Bay and DiscoveryBay. On more exposed coasts, they are composed of pebbly or gravelly, silty sand with shellfragments, but can include cobbles and boulders. The pale phototone of beach sand, forming anarrow fringe around the natural coastline, is clear on aerial photographs. This phototone canusually also be detected beneath shallow waterRaised beach deposits, or high level storm beaches, occur behind the contemporary sand beachand are composed of gravelly coarse sand with scattered pebbles. The beaches attain a maximumelevation of 6 mPD. There is no unequivocal evidence in the district for former, higher sealevels. In places, the deposits form sand barriers across river mouths, resulting in the formationof freshwater lagoons with extensive alluvial tracts inland. Boulders, cobbles and pebblesconstitute the beach deposits on more exposed coasts. These have been distinguished from thebeach sands.DetailsTai O. The south side of Tai 0 Island has a fringe of alluvial and beach deposits (032 128) adjacent to extensiveintertidal mud flats. Beach bars occur east of the Police Post and in the middle of the town (040 128). The originalsettlement was established on sand bars in the estuary.Sham Wat Wan - Tin Sam. Along this northeastern coast, with the exception of the extensive boulder beaches onthe exposed coast between Tai O and Sham Wat Wan (044 139 and 054 146) the beaches are restricted, andlargely confined to narrow, curved back beaches in the deeply indented, sheltered bays of Sham Wat Wan (065144), Sha Lo Wan (079 168) and Hau Hok Wan (087 168). A narrow sand beach has developed along the coastalmargin of the Tin Sam delta (103 167). A boulder beach occurs in the shallow bay at Sain Shek Wan (Plate 45,070158), lying on a rock platform cut in the underlying Lok Ma Chau Formation.'' Tung Chung. The bay (Tung Chung Wan) east of San Tau contains extensive sand bars and sand banks that areexposed at low tide.Chek Lap Kok (prior to development). The largest deposits were formed in sheltered bays, particularly at ShamWan and Fu Tei Wan. High back beach deposits, rising to 5.5 mPD, occurred behind'the sand beach at Sham WanTsuen. The beach sand at Sham Wan (116 197) filled much of the shallow bay, extending from low water mark toa height of about 3 mPD. The sand formed a broad dune, through which a stream was incised. Sand barscharacterized the tidal zone. The material forming the beach was light brown and varied from coarse sand to finegravel, with some mud. Pebble-sized fragments of rock littered the surface of the beach. They probably resultedfrom recent stone cutting around the bay. The beach at Fu Tei Wan (110 180) extended inland for 100 m from thehigh water mark. It was intersected by a shallow borehole (89/3955,10992 17950) that showed sand with 3 to 16%mud and a trace of shell fragments at least 3.8 m thick. The deposit was contiguous with marine sand deposits. Thebeach rose to 4 rnPD, and was backed by partially eluviated slope deposits. The form of the beach was largelydetermined by extensive sand digging this century. The beach at Cheung Sha Lan (110 197) was composed of lightbrown coarse sand with some shell fragments.Archaeological excavations in back beach deposits at Sham Wan revealed a layered sequence of coarse to mediumsand, interspersed with remains dated to the both the Tang Dynasty (c, 1 000 years old) and Late Neolithic (3 500-5 000 years old) (W Meacham, oral communication, 1993). A similar investigation at Sham Wan Tsuen revealed abasal coarse beach sand resting on bedrock at about 3 mPD. Artefacts found in the sand were over 5 000 years old(W Meacham, oral communication, 1991). Overlying this was 3 m of fine sand and soil containing remains rangingfrom Late Neolithic, through the Tang Dynasty, to the Ching Dynasty.Tai Ho Wan - Yam O Wan. This section of the coast has been extensively modified by cutting and reclamationassociated with the building of the North Lantau Expressway, However, prior to the development, the beaches fromTai Ho Wan to Ngau Tau Wan consisted of sand and cobbles, with areas of clean sand exposed that werecharacterized by a sharp break in the gradient near high water mark. Boulder streams from the adjacent slopesextended into the coastal zone. The beaches from Siu Ho Wan to Sham Shui Kok and Tai PaBg Po wore dominantlya mixture of sand, cobbles and boulders. The sand was either exposed as a narrow strip above high water mark, orwas completely obscured by cobbles. In most of the intervening areas, the slope deposits were eroded and eitherreworked into beach deposits, or entirely removed, exposing bare rock.Penny's Bay. Prior to reclamation for the shipyards, extensive sandy beach deposits occurred along the shelterednortheastern shore of Penny's Bay.116,