Question 9 Identify this sedimentary structure and determine how it formed This structure is a dike showing course mafic grains on the bottom and finer, aphanitic grains towards the top. Graded bed, I notice the course sediments at the bottom and finer sediments on top. This fining upward sequence indicates deposition in a deep marine environment by a might turbidity current. Identiry this sedimentary structure and determine how it formed An angular unconformity, this structure develops as a result of sediment being deposited, uplifted and then additional sediment is deposited on top. Cross Bedding, this structure can form in a marine or continental sedimentary environment. As sand is transported by wind or water, dunes are created. When transportation direction changes so does the angle of sediment deposition. Basin and Range, this structure indicates large NE trending mountain ranges and valleys, indicating a continental sedimentary environment Ripple Marks, this structure generally indicates an environment with moving water: a stream or a tidal area for example. dentify this sedimentary structure and determine how it formed Dike swarm, this structure indicates intrusion of a felsic magma into a host rock. Mud cracks, this structure indicates an environment that was once wet, but eventually dried out creating cracks that were eventually filled with dust and sediment. Look carefully at these sediments and make observations. How were these fossilized sediments formed and deposited?.