ANSWER: Correct Chapter 1 Question 7 Â­ True/False Part A A scientific theory is a tentative or untested explanation that is proposed to explain scientific observations. This preview has intentionally blurred sections.
Gravel /ËÉ¡rÃ¦vÉl/ is a loose aggregation of rock fragments. Gravel is classified by particle size range and includes size classes from granule- to boulder-sized fragments. In the Udden-Wentworth scale gravel is categorized into granular gravel (2 to 4 mm or 0.079 to 0.157 in) and pebble gravel (4 to 64 mm or 0.2 to 2.5 in).
These are fragments or pieces of rock or minerals. The composition of clastic sedimentary rocks is divided into three types-clay/silt, sand and gravel. Clay and silt are less than 1/16 mm. These are not visible to the unaided eye. Sand is clasts between 1/16 and 2 mm in size, and gravel is greater than 2 mm.