Kewujudan Formasi Lambir di Sinklin Ulu Bok, Sarawak Utara

702001-100997-794-B
Author : Lim Chun Hui and Mohd. Shafeea Leman
Publication : Bulletin of the Geological Society of Malaysia
Page : 1-5
Volume Number : 35
DOI : https://doi.org/10.7186/bgsm35199401

Bulletin of the Geological Society of Malaysia, Volume 35, July 1994, pp. 1-5

 

Kewujudan Formasi Lambir di Sinklin Ulu Bok, Sarawak Utara

(The occurrence of Lambir Formation in Ulu Bok Syncline, North Sarawak)

LIM CHUN HUI AND MOHD SHAFEEA LEMAN

Jabatan Geologi, Universiti Kebangsaan Malaysia, Bangi, Selangor

 

Abstrak: Jujukan litologi dalam Sinklin Ulu Bok di Sarawak Utara telah dinamakan sebagai Formasi Belait oleh ahli geologi terdahulu menerusi kajian gambar udara dan pemetaan geologi. Pemetaan geologi kini menunjukkan bahawa istilah Formasi Belait tidak sesuai untuk sinklin ini. Padahal, jujukan litologi dalam sinklin ini memperlihatkan ciri-ciri Formasi Lambir. Kedua-dua formasi ini boleh dibezakan daripada kewujudan litofasies berkapur, konkresi siderit dan fosil. Kehadiran litofasies berkapur, konkresi siderit dan fosil yang melimpah menunjukkan jujukan ini berpihak kepada Formasi Lambir, sementara ketiga-tiga ciri tersebut jarang dijumpai di dalam Formasi Belait. 

https://doi.org/10.7186/bgsm35199401

 

Abstract: The lithologic sequence of the Ulu Bok Syncline in North Sarawak was named the Belait Formation by previous geologists through areal photograph studies and geological mapping. Current geological mapping shows that the term Belait Formation is not suitable for this syncline. The lithologic sequence in this syncline revealed the characteristics of the Lambir Formation instead. These two formations can be differentiated by the occurrences of calcareous lithofacies, siderite concretions and fossils. The presence of calcareous lithofacies, abundant siderite concretions and diverse faunas in the Ulu Bok Syncline indicate that the sequence belongs to the Lambir Formation, whereas all these criteria are hardly found in the Belait Formation.