Chapter 7 Notes - sedimentary rocks a Compaction most...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 7: Sedimentary Rocks I) Sedimentary rocks: made of sediments that are from weathering A) Constituent 5% by volume of earth’s outer 16km B) At the surface about 75% is sedimentary rocks C) Comprises a relatively thin and discontinuous layer in uppermost portion of crust D) Contains fossils and is important economically II) Diagenesis: all of the chemical, physical, and biological changes that take place after sediments are  deposition and during and after lithification A) Promoted by burial B) Subjected to increasingly higher temp. and pressure C) Occurs within upper few km. of earth’s crust at temp. less than 150 o  to 200 oc D) Includes: 1) Recrystallization: development of more stable minerals from less stable ones 2) Lithification: processes by which unconsolidated sediments are transformed into solid 
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: sedimentary rocks a) Compaction: most common physical change i) Weight of overlying material compresses the deeper sediments ii) Reduction in pore space—water is driven out iii) Most significant process in fine-grained sedimentary rocks b) Cementation: most important process by which sediments are converted to sedimentary rock i) Chemical diagenetic change • Involves precipitation of minerals among individual sediment grains • Cementing materials are carried in solution by water percolating through open spaces b/t particles • Cement precipitates onto sediment grains, fills open spaces, and joins particles ii) Addition of cement reduces its porosity iii)...
View Full Document

This note was uploaded on 04/02/2008 for the course GLG 201 taught by Professor Libarkin during the Spring '07 term at Michigan State University.

Ask a homework question - tutors are online