1993 Fiscal Year Final Research Report Summary
Variation of ion adsorption capacity of smectite during diagenesis
| Project/Area Number |
03640671
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
鉱物学(含岩石・鉱床学)
|
|---|
| Research Institution | Nagoya Institute of Technology |
|---|
Principal Investigator |
UNO Yasuaki Nagoya Institute of Technology Faculty of Engineering, Professor, 工学部, 教授 (90029702)
|
|---|
| Project Period (FY) |
1991 – 1993
|
| Keywords | Diagenesis / Smectite / Bentonite / Acid clay / Ion adsorption / Excange cations / Layr charge / Dehydration |
|---|
| Research Abstract |
Variations of mineralogical properties of smectite during diagenesis were investigated for clay samples in bentonite and acid clay deposits in Japan and United States of America. The results are as folllows.
1. Smectites have various cation exchange capacities. Specimens from lower horizon of deposits tend to have small amount of layr charge.
2. Plagioclase and volcanic glass in original rocks alter to smectite during diagenesis. The ratio of interlayr sodium to calcium is larger than that in original materials.
3. Capcity of ion adsorption of smectites decreases by preheating treatment.
4. Differential thermal analysis was made under controlled steam presssure. It was found that dehydration temperature rises in high water vapor pressure.
5. Layr charge and substitution of cations in tetrahedral and octafedral site in crystal structure affect thermal properties of smectites. Dehydration is higher than that of the specimens having large value of layr charge.
The vatiation of layr charge is considered to be caused by transformation of expandable layr of smactites to non-expandable layr during diagenetic
|
