Plate� Tectonic Setting of Alluvial Basins
are deposited across the suture, or (c) by identifying
detrit us in a basin"f ill that can only have been de"
rived from the adjacent terrane. In the cas e of the
thir d cr it erion, pr ovenance studies may also be used
to demonstr at e post¥suture displacement, if the de"
tritus does not match the petr ology of the source
from which paleogeographic analysis indicates the
detritus should have come. Examples of both these
Fig. 11.75. The development of successor basins at the
margins of terranes. A and C are terranes which amalgam"
ated along the complex suture zone Z. Arrows indicate
typical dispersal of sediment following terrane amalgam"
ation. (Bluck 1991)
PENINSULAR
TERRANE
:i::5: carbonates
• •· · • closfics
:... .
-:.argillite
=c hert
vvv silicic luffs
A·li·A basatfwondesile
vo!conicloS!ics
= basol!ic pillows,
H111IL flows a hypobyssals
Fig. 11.76. Amalgamation history of the major terranes
of British Columbia and southern Alaska. Note the use of
provenance linkages and overlap assemblages to docu411
cases have been cited by Schermer et al. (198 4) and
Bluck (1991). Schermer et al. (1984) stated:
"An example of an overlap assemblage is the Late Creta�
ceous Gravina-Nutzotin belt of southern Alaska, which
links the Wrangellia and Alexander terranes; an example
of a provenancial linkage is provided by the Middle to
Upper Jurassic strata of the Bowser Basin of British Co¥
lumbia, which are deposited on the Stikine terrane and
contain debris from the Cache Creek terrane."
These relationships are both indicated in the terrane-amalgamation diagram compiled by Saleeby
(1983; Fig. 11.76). Discussing the Devonian sedimentary fill of the Midland Valley of Scotland, Bluck
(1991) stated that sediments banked against the fault
which forms the southeast margin of this basin, the
Sout hern Uplands Fault, "contain ab undant igneous
and metamorphic clasts up to boulder size, but in the
direction from which they were transported lies the
Southern Uplands, a sequence of gr eywackes and
shales. In this instance a sour ce block has been laterally displaced or overthrust by the gr eywacke sequence."
An example of the complex pr ob lems in plate
kinematics that terrane amalgamation histories
can set up was described by Kleinspehn (1985). She
examined the Tyaughton-Met how Basin in southwester n Br it ish Columbia, a basin formed adj acent
- amalgamation episode
-- accretion episode
� pluton link
••••• provenance link
--;::: ::- overlap
u unconformity
ment amalgamation histories. (Saleeby 1983, reproduced
with permission from the Annu Rev Earth Planet Sci vol ll,
© 1983, by Annual Review Inc.)
are deposited across the suture, or (c) by identifying
detrit us in a basin"f ill that can only have been de"
rived from the adjacent terrane. In the cas e of the
thir d cr it erion, pr ovenance studies may also be used
to demonstr at e post¥suture displacement, if the de"
tritus does not match the petr ology of the source
from which paleogeographic analysis indicates the
detritus should have come. Examples of both these
Fig. 11.75. The development of successor basins at the
margins of terranes. A and C are terranes which amalgam"
ated along the complex suture zone Z. Arrows indicate
typical dispersal of sediment following terrane amalgam"
ation. (Bluck 1991)
PENINSULAR
TERRANE
:i::5: carbonates
• •· · • closfics
:... .
-:.argillite
=c hert
vvv silicic luffs
A·li·A basatfwondesile
vo!conicloS!ics
= basol!ic pillows,
H111IL flows a hypobyssals
Fig. 11.76. Amalgamation history of the major terranes
of British Columbia and southern Alaska. Note the use of
provenance linkages and overlap assemblages to docu411
cases have been cited by Schermer et al. (198 4) and
Bluck (1991). Schermer et al. (1984) stated:
"An example of an overlap assemblage is the Late Creta�
ceous Gravina-Nutzotin belt of southern Alaska, which
links the Wrangellia and Alexander terranes; an example
of a provenancial linkage is provided by the Middle to
Upper Jurassic strata of the Bowser Basin of British Co¥
lumbia, which are deposited on the Stikine terrane and
contain debris from the Cache Creek terrane."
These relationships are both indicated in the terrane-amalgamation diagram compiled by Saleeby
(1983; Fig. 11.76). Discussing the Devonian sedimentary fill of the Midland Valley of Scotland, Bluck
(1991) stated that sediments banked against the fault
which forms the southeast margin of this basin, the
Sout hern Uplands Fault, "contain ab undant igneous
and metamorphic clasts up to boulder size, but in the
direction from which they were transported lies the
Southern Uplands, a sequence of gr eywackes and
shales. In this instance a sour ce block has been laterally displaced or overthrust by the gr eywacke sequence."
An example of the complex pr ob lems in plate
kinematics that terrane amalgamation histories
can set up was described by Kleinspehn (1985). She
examined the Tyaughton-Met how Basin in southwester n Br it ish Columbia, a basin formed adj acent
- amalgamation episode
-- accretion episode
� pluton link
••••• provenance link
--;::: ::- overlap
u unconformity
ment amalgamation histories. (Saleeby 1983, reproduced
with permission from the Annu Rev Earth Planet Sci vol ll,
© 1983, by Annual Review Inc.)