Reinhard,
I have seen a lot of soft sediment deformation features in BIFs
from Michigan and Minnesota.
cheers,
eric
On Nov 26, 2009, at 9:54 AM, Reinhard O. Greiling wrote:
> Dear Christine,
> There are numerous "sandstone dykes" in Scandinavia, but
> publications, if any, are only in local journals. The dykes appear
> to be quite common just below the sub-Cambrian peneplain, e.g. in
> southern Sweden, or along the Caledonian margin. I also came across
> some sedimentary dykes in BIF-related rocks in the Western Desert of
> Egypt, just beneath the basement-cover surface.
> Regards,
> Reinhard Greiling
>
> ----- Message from [log in to unmask] ---------
> Date: Thu, 26 Nov 2009 06:39:18 -0700
> From: Christine Siddoway <[log in to unmask]>
> Reply-To: Tectonics & structural geology discussion list <[log in to unmask]
> >
> Subject: Re: Anderson Stress Meeting: September 2010 reminder
> To: [log in to unmask]
>
>
>> Greetings, Carl and others,
>> AMS on sandstone intrusions: Mike Petronis and I have an
>> investigation
>> underway of sandstone dikes within crystalline rock in the Front
>> Range of
>> Colorado. Our recent abstract with initial results is at:
>> http://aapg09.mapyourshow.com/2_1/sessions/session.cfm?ScheduledSessionID=15
>> 32. The scale of the intrusions, incidentally, is 5 cm to >7
>> meters, with
>> many exceeding 2 m in width.
>>
>> I'd like to now ask, can any list members tell me of other examples
>> of
>> clastic dikes within a crystalline host? My web searches yield
>> little!
>>
>> Regards,
>> Christine Siddoway
>>
>>
>> On 11/26/09 4:24 AM, "Carl Stevenson" <[log in to unmask]>
>> wrote:
>>
>>> Hi all,
>>>
>>> Sedimentary intrusions - does anyone know of any AMS (anisotropy
>>> of magnetic
>>> susceptibility) work on these?
>>>
>>> Desperately resisting getting drawn in to a semantic debate, I
>>> think 'igneous
>>> intrusion' is fine. I guess it is as opposed to igneous extrusion
>>> - lavas and
>>> ash etc. Sometimes in when subvolcanic roots are exposed it is
>>> actually
>>> equivocal. There are instances when ash can fall back into a vent.
>>>
>>> An example I am aware of is:
>>> ALMOND, D. C. 1977. Sabaloka Igneous Complex, Sudan. Philosophical
>>> Transactions of the Royal Society of London Series a -
>>> Mathematical Physical
>>> and Engineering Sciences, 287, 595-633.
>>>
>>> Cheers
>>> Carl
>>>
>>> -----Original Message-----
>>> From: Tectonics & structural geology discussion list
>>> [mailto:[log in to unmask]] On Behalf Of Stu Clarke
>>> Sent: 26 November 2009 10:23
>>> To: [log in to unmask]
>>> Subject: Re: Anderson Stress Meeting: September 2010 reminder
>>>
>>> Don't you hate it when someone gets that email in just before
>>> you......
>>>
>>> I too have no particular stand on terminology, but I too was
>>> surprised by
>>> the stated scale of sedimentary intrusions. I have examined large
>>> scale
>>> sedimentary intrusions in deltaic settings and currently work with
>>> colleagues using oil-industry datasets on the same thing. I don't
>>> think
>>> sedimentary intrusions have to be small scale......
>>>
>>> Stu
>>>
>>>
>>> -----Original Message-----
>>> From: Tectonics & structural geology discussion list
>>> [mailto:[log in to unmask]] On Behalf Of Macdonald,
>>> Professor
>>> David I. M.
>>> Sent: 26 November 2009 10:11
>>> To: [log in to unmask]
>>> Subject: Re: Anderson Stress Meeting: September 2010 reminder
>>>
>>> Dear Eric
>>> I have no particular stand on the terminology for igneous rocks,
>>> but you are
>>> incorrect in your assertions on the scale of sedimentary
>>> intrusions. Salt
>>> is a sedimentary rock which can be injected through kilometers of
>>> strata in
>>> bodies hundreds of metres to kilometers across. Anyone who has
>>> ever worked
>>> on deltas can point to mud diapirism on a similar scale. Even the
>>> humble
>>> sand injection feature is much larger than you make out; your
>>> description
>>> seems to be of sand filling pre-existing cracks, whereas most sand
>>> injections are of a fluid slurry under pressure. These intrusions
>>> can be
>>> huge. In the Mesozoic forearc basin of the Antarctic Peninsula,
>>> sandstone
>>> dykes have been mapped with MINIMUM dimensions: 6 km long, cutting
>>> 350 m of
>>> strata, and 1 m wide. For more examples, see, among other papers:
>>>
>>> Hurst A. & Cartwright J. A. Eds. 2007. Sand Injectites:
>>> Implications for
>>> hydrocarbon exploration and production. Memoir 87 American
>>> Association of
>>> Petroleum Geologists
>>>
>>> Hurst A., Cartwright J. & Duranti D. 2003. Fluidization
>>> structures in
>>> produced by upward injection of sand through a sealing lithology.
>>> In:
>>> Subsurface sediment mobilization (eds. Van Rensbergen P.,Hillis
>>> R.,Maltman
>>> A. J. & Morley,C.K.), Geological Society Of London, London, 123-127
>>>
>>> Jonk R., Hurst A., Duranti D., Mazzini A., Fallick A. E. &
>>> Parnell J.
>>> 2005.The origin and timing of sand injection, petroleum migration
>>> and
>>> diagenesis: the Tertiary petroleum system of the South Viking
>>> Graben, North
>>> Sea. AAPG Bulletin, 89, 329-357
>>>
>>> Hurst A. & Duranti D. 2004. Fluidisation and injection in the
>>> deep-water
>>> sandstones of the Eocene Alba Formation (UK North Sea).
>>> Sedimentology, 51,
>>> 3, 503-529
>>>
>>> Hope this helps
>>> David Macdonald
>>>
>>> -----Original Message-----
>>> From: Tectonics & structural geology discussion list
>>> [mailto:[log in to unmask]] On Behalf Of Eric Essene
>>> Sent: 26 November 2009 07:39
>>> To: [log in to unmask]
>>> Subject: Re: Anderson Stress Meeting: September 2010 reminder
>>>
>>> Rob,
>>> The term igneous intrusions is functionally a terrible term, a
>>> distinction without a difference. More than 99.9% (or more?) of the
>>> time it means igneous rocks where the term is redundant. If one
>>> talks
>>> about sedimentary intrusions it is on a meter scale feature,
>>> commonly
>>> even less--I have seen some down to cm scale. When they formed and
>>> well afterward they did not look like dikes, just fractures filled
>>> with loose sediment. I discount the poor term "sandstone dikes" as
>>> needing yet another confusing term.
>>> On the other hand salt domes are metamorphic (recrystallized)
>>> but
>>> not molten rock, well a little brine. They were not in the
>>> sedimentary group during formation. Yes, we have diapirs of
>>> metamorphic rock, although a lot of those gneiss domes probably
>>> have a
>>> little melt. I would agree about metamorphic diapirs but simply
>>> would
>>> not call them metamorphic intrusions to avoid confusion on a
>>> transitional rock. Gneiss domes are a nice description for them.
>>> It must be exceedingly rare for igneous petrologists/geochemists
>>> to be presenting data on "sand dikes". Salt domes are much larger
>>> but are as they form. Do you know of any igneous petrologist/
>>> geochemist who would report on them in your symposium? So
>>> "sandstone
>>> dikes" are fractures filled with loose clastic material and water,
>>> salt diapirs are all metamorphic and may have brine, gneiss domes
>>> are
>>> often partial melts then at least partly igneous, and the term
>>> "igneous intrusion" is clearly redundant to the average passerby.
>>> Is
>>> this really a useful terminology?
>>> cheers,
>>> eric
>>>
>>> On Nov 26, 2009, at 12:17 AM, Butler, Robert wrote:
>>>
>>>> Eric
>>>> Actually - there are lots of non-igenous intrusions in basins -
>>>> sandstone dykes through 100s metres of strata. Not to mention mud
>>>> diapirs, salt etc etc.... gas chimneys....
>>>> go google!
>>>> Cheers
>>>> Rob
>>>>
>>>> ________________________________________
>>>> From: Tectonics & structural geology discussion list
>>> [[log in to unmask]
>>>> ] On Behalf Of Eric Essene [[log in to unmask]]
>>>> Sent: 26 November 2009 05:09
>>>> To: [log in to unmask]
>>>> Subject: Re: Anderson Stress Meeting: September 2010 reminder
>>>>
>>>> Rob, Zoe, and all,
>>>> Igneous intrusions as opposed to all those sedimentary plutons?
>>>> The phrase is nearly always meaningless and should not be used.
>>>> Sounds like a great trip.
>>>> cheers,
>>>> eric
>>>>
>>>>
>>>> On Nov 25, 2009, at 11:28 PM, Butler, Robert wrote:
>>>>
>>>>> Dear all
>>>>> As we get our diaries together for 2010 we thought it timely to
>>>>> remind you of the conference next year:
>>>>>
>>>>> Stress controls on faulting, fracturing and igneous intrusion in
>>>>> the
>>>>> Earth's crust
>>>>>
>>>>> A meeting to commemorate the work of Ernest Masson Anderson on the
>>>>> 50th anniversary of his death.
>>>>>
>>>>> 6-8 September 2010 at the University of Glasgow, UK
>>>>>
>>>>> Organisers: Zoe Shipton, Rick Sibson, Dave Healy, Rob Butler
>>>>>
>>>>> We will send out details of the meeting ("First Circular") in
>>>>> January -
>>>>> Abstract deadline will be end April with a preliminary programme
>>>>> drawn up through May.
>>>>> We are also planning a fieldtrip to the Hebrides and NW Scotland
>>>>> to
>>>>> examine a variety of faults and the Tertiary igneous complexes.
>>>>> Again - further information will be included in the first
>>>>> circular.
>>>>>
>>>>> Hope to see a bunch of you in Scotland next September!
>>>>> Zoe, Rick, Dave and Rob.
>>>>>
>>>>>
>>>>> The University of Aberdeen is a charity registered in Scotland, No
>>>>> SC013683..
>>>>>
>>>>>
>>>>
>>>>
>>>> The University of Aberdeen is a charity registered in Scotland, No
>>>> SC013683..
>>>>
>>>>
>>>
>>>
>>> The University of Aberdeen is a charity registered in Scotland, No
>>> SC013683.
>>
>
>
> ----- End message from [log in to unmask] -----
>
>
>
> --
> Prof. Dr. Reinhard O. Greiling FGS
> Lehrstuhl für Strukturgeologie und Tektonophysik
> Institut für Angewandte Geowissenschaften
> Karlsruher Institut für Technologie (KIT)
> Hertzstraße 16
> 76187 Karlsruhe
> FR Germany
>
> Telefon 0721-6082141
> Fax 0721-6082138
>
> http://www.agk.uni-karlsruhe.de/struktur/
> e-Post [log in to unmask]
>
> KIT - Universität des Landes Baden-Württemberg und nationales
> Großforschungszentrum in der Helmholtz-Gemeinschaft
>
>
>
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>
>
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