Flash cards to study for Missouri State University's Stratigraphy class Exam 1. Fall 2013
Terms : Hide Images
| 947583486 | clasts | chunks or broken fragments of rock with a standardized clast size scale | 1 | |
| 947583487 | matrix | finer clasts (like sand) in a rock | 2 | |
| 947583488 | cement | glue (chemical) that holds the sand and larger clasts together as a rock | 3 | |
| 947583489 | clastic texture | rocks containing clasts of existing rocks that were transported and deposited; grains are not interlocked | 4 | |
| 947583490 | crystalline texture | grains are interlocked; results from precipitation of mineral crystals; most igneous rocks exhibit this texture | 5 | |
| 947583491 | sorting and roundness | variation in grain size; well sorted = little variation; sharpness or smoothness of the corners of grains | 6 | |
| 947583492 | provenance | all aspects of the sources from which a sedimentary rock is derived | 7 | |
| 947583493 | diagenesis | all changes that occur to sedimentary rocks from time of deposition until time of examination; including texture, composition, and other physical properties | 8 | |
| 947583494 | detrital | rocks consisting of clasts of pre-existing rocks and minerals that have been transported and deposited as fragments; termed terrigenous because they represent eroded material | 9 | |
| 947583495 | siliciclastic | terrigenous material mainly consisting of quartz and other silica-rich minerals | 10 | |
| 947583496 | chemical (sed. rock) | rocks that result from precipitation of minerals as dissolved constituents reach saturation; examples are evaporites such as anhydrite, gypsum, and halite | 11 | |
| 947583497 | What are 2 common factors which can control the color of a sedimentary rock's cement? | Carbon-rich (function of oxygen) creates a black color. Iron-rich creates a reddish to orange color. | 12 | |
| 947583498 | The terms clastic and detrital are used interchangeably. What is the technical difference between the two? | Detrital refers to material eroded from the Earth and material (coasts) that are transported away from the weathering site. | 13 | |
| 947583499 | Will a rock's coasts or cement provide more information about its provenance? How about its history of diagenesis? | The clasts will provide more information about the provenance. Type of rock of the clasts will provide info about the composition, location and relief. Cement will provide information about its diagenesis. Type of cement will clue towards what changes have occurred. | 14 | |
| 947583500 | Detrital is to clastic as chemical is to ____ | crystalline | 15 | |
| 947583501 | Would a very dark color give the most information about a rock's provenance, depositional environment, or its diagenesis? How about a pink color imparted by the grains? | Dark color would give info about a rock's EOD, signifying a lack of oxygen during deposition. Pink color indicates provenance, that it was derived from an orthoclase/granitic source. | 16 | |
| 947583502 | Describe 3 pieces of info that might be inferred from examining a hand sample of a sedimentary rock. | Source area, transportation, physical setting (EOD) | 17 |
