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Yam O Wan - Yi Fak Wan. Small, isolated debris deposits occupy short valleys on the northern flanks of Lai PikShan (206 201) and Tai Shan (208 205, 213 204), with large developments on their southern flanks (208 200). Along lobate deposit fills the valley (188 193) behind Yi Pak Wan, below Tai Che Tung. The material generallycomprises a coarse, blocky-weathering debris, derived from the feldsparphyric rhyolite, set in a sandy, silty matrix.Boulder streams occupy the upper slopes. These are fed by narrow boulder trails that extend down incipientdrainage lines from the ridge crests. Downslope, the streams feed extensive debris sheets which have, in severalareas, been eroded to expose boulders, separated by matrix-rich debris lobes between gully lines. The boulders aretypically small, but occasionally exceed 20m. Locally, the deposits extend to the coast, where they either form fans,at the bottoms of narrow valleys, or truncated lobes. The deposits are widespread and on a large scale in this area.Trains of debris leading downslope from rock outcrops on ridges are common. Subsequent incision of the depositshas exposed bedrock in the deeper stream courses.Lin Fa Shan - Mui Wo. Extensive sheets of boulders occur on the steep upper flanks of Lin Fa Shan (Plate 44),except on the steep eastern slope on which bare rock is exposed. Lower down the gentler slopes, debris streamsappear and a thin veneer of debris is continuous from around the Forestry Office to Luk Tei Tong.Silver Mine Bay - Tung Wan Tau. The hills have a thin cover of debris. Slopewash deposits have accumulated inthe gentle valleys, although alluvial fills are rare. Boulder streams are uncommon, but debris is widely developed.Chi Ma Wan. Debris deposits are very restricted on the granitic rocks of the Chi Ma Wan peninsula, largelycomprising a thin litter of isolated boulders on the open slopes and eluviated boulder trains in the valleys.Tong Fuk Coarse, bouldery slope deposits choke the short, steep valleys on the southern slopes of Sunset Peakand Lantau Peak. The largest deposit (106 106) occurs above Tong Fuk, where an extensive dendritic system feedsdown from Lantau Peak to the coastal fan. A thin mantle of sandy, silty slope deposits cover the valley sides, largeareas of which were mobilised as shallow debris slides, or long linear, debris flow-slides in minor tributariesduring the November 1993 rainstorms, leaving hundreds of fresh scars over these slopes.Shek Pik. On the southwestern flanks of Lantau Peak, and below Muk Yue Shan and Sze Tsz Tau Shan, thedendritic drainage lines converge on the Shek Pik valley. They are all occupied by slope deposits, consisting ofcobbles in a sandy matrix, which feed into the alluvial fan at Shek Pik.Tai Horn Shan - Sham Hang Lek, Slope deposits have a restricted development in the short valleys draining offthe peaks of southwestern Lantau Island. They are predominantly narrow, linear streams, composed of sandy,gravelly debris with some boulders.Talus (Rockfall Deposits)Talus predominantly consists of angular rock fragments., often large, derived from, and lying atthe base of, a cliff or very steep rocky slope (Bates & Jackson, 1987). The fragments have beentransported downslope by a combination of falling, sliding, or rolling. They commonly overliePleistocene slope deposits in the district, and are still accumulating.The talus is restricted to very confined deposits, which are mostly unmappable at the 1:20,000scale. The composition is very variable, but generally comprises an unsorted mass of gravel,pebbles, cobbles and boulders., with only a sparse sandy matrixDetailsLantau Peak. Small talus accumulations occur below several small, free faces in the lavas and tuffs of LantauPeak, the largest forming a linear scree (091 125) on the western flanks. The deposit comprises large, angularboulders with no visible matrix, CKJCurring as a jumbled pile.Beach DepositsBeach deposits are narrow, laterally extensive features composed of unconsolidated,predominantly sand-sized material extending landwards from the low-water mark to a cliff line,or storm beach, that marks the upper limit of wave action, These deposits are laterally continuouswith the littoral and sublittoral sands of the Hang Hau Formation. The beach deposits in thedistrict mostly consist of clean, pale yellow sand, and several, such as Cheung Sha Beach are115