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.
>
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Prof. Dr. Reinhard O. Greiling FGS
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