Weathering Profile Development Below the Yuen Long Plain, Western New Territories, Hong Kong

Some 2,651 borehole logs have been interpreted and entered in to a computer database, which has been used to model the morphology and depth of the weathering front in the Yuen Long area. The results are used as a basis for correlation between the surface topography, the morphology of the weathering front, and the main structural trends. This study has focused on examining the different weathering characteristics between granitic, volcanic, and metamorphic lithologies, and on the influence of the geological discontinuities. Attention has also been paid to corestone development and distribution, and the thickness and distribution of superficial deposits. The results of this and similar studies play an important role in developing models for interpreting, and ultimately for predicting weathering patterns over the main rock types in Hong Kong.

2,651個鑽孔的資料被解讀，並被輸入電腦數據庫，藉此模拟元朗地區風化帶的形態和風化深度。其結果被用來作爲分析地表 地貌、風化形態以及主要構造趨勢之間相互關係的基礎。該硏究集 中探討花崗岩、火山岩及變質岩不同岩性的風化特征，以及地質上 的不連續對風化作用的影響。該硏究亦特別注意核岩的發展與分 佈，以及第四紀沉積物的厚度與展佈。這項硏究以及類似硏究的成 果，對於建立模型以詮釋乃至最終預測本港主要岩石類型的風化模式十分重要。