We could always change the title of the conference to "Stress controls
on faulting, fracturing and intrusion/injection of magmas, melts, salt
and other sediments in the Earth's crust" but it'd be a bit cumbersome.
It's been fascinating hearing about the enormous variety in
intrusion/injection types, and we'd welcome abstracts on any of these
topics. The theme of the conference is stress, and I imagine there's a
whole lots of interesting data out there related to stress driving or
influencing "non-igneous" intrusions.
Look forward to reading your abstracts in April...!
Zoe
Alan Gibbs wrote:
> For those of you who may have missed these things have a look at:
>
> http://pgc.lyellcollection.org/content/6/133.abstract
>
> More if you google "clastic injectites" which will give you some insight
> into how big and potentially interesting these things are.
>
> Injectite or intrusion folks?
>
> alan
>
> -----Original Message-----
> From: Tectonics & structural geology discussion list
> [mailto:[log in to unmask]] On Behalf Of Jackson, Christopher A -
> L
> Sent: 26 November 2009 15:14
> To: [log in to unmask]
> Subject: Re: Anderson Stress Meeting: September 2010 reminder
>
> Hi All,
>
> Seems like we are straying into a discussion about 'forcibly-intruded'
> clastic dykes (typically injected upwards) vs. 'passively-emplaced' clastic
> dykes which fill in long-lived, open fractures (i.e. ones forming in
> metamorphic basement as Bob describes below). This is OK, as long as we are
> al clear on what we are talking about.
>
> Chris
>
> P.S. Bob: I'll have one of the JSG pre-prints if you don't mind!
>
>
> ---------------------------------------------------------------
> Dr Christopher A-L Jackson
> Statoil Senior Lecturer in Basin Analysis Department of Earth Science &
> Engineering Imperial College Prince Consort Road London
> SW7 2BP
> ENGLAND
>
> email: [log in to unmask]
> web: www.imperial.ac.uk/people/c.jackson
> phone: +44(0)2075947450
>
> -----Original Message-----
> From: Tectonics & structural geology discussion list
> [mailto:[log in to unmask]] On Behalf Of HOLDSWORTH R.E.
> Sent: 26 November 2009 14:35
> To: [log in to unmask]
> Subject: Re: Anderson Stress Meeting: September 2010 reminder
>
> Christine and all,
>
> We here at Durham have had some interest in clastic infills in crystalline
> rocks - including ones that have been injected. For example, try Beacom et
> al. 1999 for examples within the Lewisian Gneisses:
>
> Beacom, L.E., Anderson, T.B. & Holdsworth, R.E. 1999. Using basement hosted
> clastic dykes as syn-rifting palaeostress indicators: an example from the
> basal Stoer Group, Scotland. Geol. Mag. 136, 301-310.
>
> I'll send you - and anyone else who want one - a reprint separately.
>
> More recently, Rich Walker who has just submitted his PhD here has found
> similar features in Tertiary basalts in the Faroe Islands and is about to
> start a post doc studying equivalent features for a further 2.5 years funded
> by a major oil company (contract pending, so i'll refrain from naming
> names). If you want I can send a pre-print of a paper we are about to submit
> to JSG on these, though they are mostly sediment fills with only minor
> injectites. He will be presenting some of his work as a poster at AGU if you
> want to come and find him or me.
>
> Finally, we also have two PhD students funded by a consortium of companies
> associated with the Clair field, west of Shetland who are studying fracture
> systems in the crystalline basement of the Lewisian Complex of NW Scotland
> (Jen Martin, Ben Franklin). Many of these fracture systems are associated
> with clastic fills and/or injectites.
> Jen will also be presenting some of her work as a poster at AGU. The
> companies are interested in this work as a substantial volume of oil is
> hosted in fractured basement in the Clair Field.
>
> Fianlly, you might also want to seek out these possibly related papers:
>
> Richter, D. 1966. On the New Red Sandstone Neptunian Dykes of the Tor Bay
> Area (Devonshire). Proceedings of the Geological Association, 77,
> 173-186
>
> Wright, V., Woodcock, N.H., Dickson, J.A.D. 2009. Fissure fills along
> faults: Variscan examples from Gower, South Wales. Geological Magazine,
> Cambridge
>
> Best wishes
>
> Best wishes
> Bob Holdsworth
>
> Prof Bob Holdsworth,
> NERC KE Fellow,
> Reactivation Research Group,
> Dept of Earth Sciences,
> University of Durham,
> Durham DH1 3LE,
> UK
> Tel +44(0)1913342299
> Fax +44(0)1913342301
> e-mail (including jsg business): [log in to unmask]
> Web:
> Dept: http://www.dur.ac.uk/earth.sciences
> RRG - http://www.dur.ac.uk/react.res/RRG_web
> Geospatial Research Ltd (GRL) - www.geospatial-research.com
>
> -----Original Message-----
> From: Tectonics & structural geology discussion list
> [mailto:[log in to unmask]] On Behalf Of Christine Siddoway
> Sent: 26 November 2009 13:39
> To: [log in to unmask]
> Subject: Re: Anderson Stress Meeting: September 2010 reminder
> Importance: High
>
> 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?ScheduledSessionI
> D=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.
--
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Zoe Shipton
Department of Geographical and Earth Sciences
University of Glasgow
Gregory Building
Glasgow G12 8QQ
+44 (0)141 330 2783
www.ges.gla.ac.uk/faff
