Scientific research trip sponsored by Hive account@mapesa to trace the river estuaries once used by the Aceh Darussalam Kingdom as a spice commodity base especially pepper in the medieval period, on the western and southern coast of Aceh.

One of our destinations is the Terbangan river estuary, in the Ladang Tuha village, Pasie Raja, South Aceh Regency, Aceh. When on location, we are faced with the interesting thing that is the Conglomerate rocks hill located at the mouth of the river. As I pointed out in the old post "Terbangan River Estuary", I will make a post "Conglomerate Sedimentary Rock At The Terbangan River Estuary".

Conglomerate

Conglomerates are sedimentary rocks formed from round pebbles and stone-sized clasts cemented by a chemical process that binds the stones together in a matrix.

Conglomerate ( /kəŋˈɡlɒmərɪt/) is a coarse-grained clastic sedimentary rock that is composed of a substantial fraction of rounded to subangular gravel-size clasts, e.g., granules, pebbles, cobbles, and boulders, larger than 2 mm (0.079 in) in diameter. Conglomerates form by the consolidation and lithification of gravel. Conglomerates typically contain finer grained sediment, e.g., either sand, silt, clay or combination of them, called matrix by geologists, filling their interstices and are often cemented by calcium carbonate, iron oxide, silica, or hardened clay. en.wikipedia.org

It takes a strong water current for the formation of conglomerate sedimentary rocks, located along a fast stream or beach with strong waves, or it could be a river bottom or an ancient coastline.

Sedimentary rock conglomerates are also seen on Mars, in image from NASA's Curiosity rover, shot on Sept. 2, 2012 with the 100-millimeter Mast Camera.

^{Image credit: www.jpl.nasa.gov}

Many gravel-sized rocks have eroded out of the outcrop onto the surface, particularly in the left portion of the frame. The outcrop characteristics are consistent with a sedimentary conglomerate, or a rock that was formed by the deposition of water and is composed of many smaller rounded rocks cemented together. Water transport is the only process capable of producing the rounded shape of clasts of this size. www.jpl.nasa.gov