Geology of the overburden and adjoining rock of the Gorleben
salt dome ....................................................... 7
1 Introduction ................................................. 9
2 Geological and structural exploration at Gorleben ........... 10
2.1 Exploration objectives ................................. 10
2.2 Exploration activities ................................. 10
2.2.1 Drilling programme .............................. 13
2.2.2 Geophysical exploration programmes .............. 15
2.2.3 Mapping of the Quaternary geology ............... 16
2.2.4 Pedological mapping ............................. 17
2.2.5 Analyses of rock samples ........................ 21
3 Description of the study area ............................... 21
3.1 Location and boundaries ................................ 21
3.2 Overview of the geologic morphology .................... 22
4 Stratigraphy, lithology and lithogenesis .................... 27
4.1 Zechstein to Cretaceous ................................ 27
4.2 Tertiary ............................................... 28
4.2.1 Paleocene ....................................... 30
4.2.2 Eocene .......................................... 31
4.2.3 Oligocene ....................................... 39
4.2.4 Miocene (Lower Miocene) ......................... 46
4.3 Quaternary ............................................. 56
4.3.1 Preglacial age (pre-Elsterian glacial stage) .... 58
4.3.2 Elsterian Glaciation ............................ 67
4.3.3 Holsteinian Interglacial ........................ 77
4.3.4 Saalian Complex ................................. 84
4.3.5 Eemian Interglacial ............................. 93
4.3.6 Weichselian Glaciation .......................... 94
4.3.7 Holocene ....................................... 101
5 Regional structure of the deeper subsurface ................ 106
5.1 Mohorovicic discontinuity ............................. 107
5.2 Crystalline surface ................................... 111
5.3 Pre-Permian surface ................................... 113
5.4 Elbe lineament ........................................ 115
5.5 Zechstein base ........................................ 119
6 Geological structure of the environs of the Gorleben salt
dome ....................................................... 123
6.1 Mesozoic structures ................................... 123
6.2 Cenozoic structures ................................... 130
7 Gorleben-Rambow salt structure ............................. 134
7.1 Differences in the development of the Gorleben and
Rambow salt domes ..................................... 134
7.2 Bedding of the Zechstein and the Mesozoic ............. 138
7.3 Bedding of the Tertiary ............................... 145
7.4 Bedding of the Quaternary ............................. 152
7.4.1 Quaternary channels ............................ 158
7.4.2 Glacigenic deformation ......................... 161
7.5 Structures below the salt structure ................... 163
7.5.1 Basement faults ................................ 165
7.6 Structures on top of the salt structure ............... 165
7.6.1 Salt table ..................................... 165
7.6.2 Cap rock ....................................... 166
7.6.3 Crestal trenches ............................... 170
8 Subrosion .................................................. 171
8.1 Subrosion in the Tertiary ............................. 171
8.2 Subrosion during the preglacial age ................... 172
8.3 Subrosion from the Elsterian Glaciation to the
Saalian Glaciation .................................... 173
8.4 Subrosion from the Eemian Interglacial until
present ............................................... 176
9 Balance of salt movements .................................. 178
9.1 Salt flow velocities and salt dome uplift ............. 178
9.2 Primary thickness of the Zechstein .................... 181
9.3 Balance of the salt volumes ........................... 183
10 Recent tectonics and recent crust movements ................ 185
11 Diapirism .................................................. 186
12 Future development of the Gorleben salt structure .......... 193
13 Summary .................................................... 193
References ................................................. 201
Abbreviations .............................................. 215
List of tables ............................................. 217
List of figures ............................................ 218
List of plates ............................................. 220
|
