SANDSTONE AND SHALE ANGCO QUARRY, TUARAN SABAH

The features rock is called sandstone and shale, donated by Angco Quarry. It is originated from Tuaran, Sabah and were formed from Oligocene – Early Miocene epoch approximately 33.9 – 15.97 million years ago.
Sandstone and shale are two distinct sedimentary rocks that form through different geological processes, each exhibiting unique characteristics.
Sandstone is primarily composed of sand-sized mineral, rock, or organic particles that are cemented together over millions of year. It forms in environments where there is an abundance of sand, such as deserts, beaches, or riverbeds. Sandstone is characterized by its granular texture, visible grains, and the presence of minerals like quartz, feldspar.
Shale, on the other hand, is a fine-grained sedimentary rock composed primarily of clay minerals, silt-sized particles, and other minerals. It forms in depositional environments where fine-grained sediments accumulate, such as lake bottoms or deep ocean floors. Shale is characterized by its fissility, meaning it easily splits into thin layers. Its color can range from gray to black, depending on the presence of organic material or minerals.
The sandstone and shale exhibited in UTP GRG is medium to fine grain sandstone interbedded with shale that inhibits greyish colour and has undergoes slightly metamorphism process of heat and pressure. This rock is interpreted to be deposited in deep water depositional environment setting.
Interbedded of shale with sandstone can be observed on the rock boulders exhibited at UTP GRG with graded bedding and load cast structure.