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Dear research colleagues,
Is there a method to detect glaciers from out of space with satellite images?
Resolution is of course the bottleneck here. So coarser than 100m image data is not beneficial.
1) What Satellite Images are most beneficial for this task?
2) What type of image data might be suited best? Is a specific choice of bands helpful or do LST provide most promising results?
3) I have encountered this work below. It seems very promising, can someone evaluate?
The final goal is to automatically generate masks in shape of these glaciers. For example with help of unsupervised k-means classification or if necessary supervised classification to recognize and distinguish between glaciers and everything else including snow-covered soil by color (examples attached, as you can see it does not work very well yet.). These masks are further a key element for the test part in a CNN project.
Here is a very nice project with very fine masks from lakes and sea instead of glaciers: https://github.com/JiahuiYu/generative_inpainting/issues/451
Since I work mostly with GEE, here are several LST datasets which I ask you to evaluate if you have more experience than me:
Cheers,
Sven Szardien
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You can use Sentinel 10mpp. Albedo is great when it is used in snow-free season
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Are there today any easy free GUI software e.g. to do with DEM this: draw a polygon, or select a feature/features/, or (automatically) somehow determine a wider area, and get the length, width and height and so on of (glacial) landform(s), or get morphometric characteristics of the selected area/part of the DEM.
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Ayan,
Thanks!
I still have a lot to learn on this topic. 55/5000
I have not yet gone very far on this issue.
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In the increasing heating of the atmosphere due to climate change Glacial Lake Outburst Floods (GLOFs) are becoming more critical in the current century. Last decades GLOFs have already taken thousand of lives.
Does the current demand of research of GLOFs and Geo-Risk-Managment fit into a Master-Thesis in "Applied Geoscience" ?
Our Institute covers Hydrogeology, Georisks and Geological Engineering.
Cheers
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Thanks Jochen Albrecht, that helped me alot and gave me a source of motivation! :)
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There are some mountaineous areas, where it is still not clear whether they have been glaciated during the late pleistocene. Though there is sometimes no typical glacial geomorphology, the bedrock is often covered by layers that are full of rounded and sharp stones. The altitude is too high to find aeolian sediments (like loess), that would make it easy to determine it as periglacial layer. The area where I found this material is situated in the Harz Mountains (Germany) in an area, that is susceptible of having been glaciated. But it has also been marked by periglacial processes afterwards. How can I clearly identify, whether these layers are periglacial or glacial till? THANKS
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Dear Gentlemen,
if you are more or less familiar with the complex geology of the Cenozoic overburden residing on the Variscan Basement in Central Germany I would express a stark warning for a simple remote-controlled image analysis. It is too small an overview of the geological situation to hand down an environment analysis. There exist a plethora of nice sections based on the mining of lignite and clay minerals in the area under question which should be added to the image and used for a more general overview. Moreover, we do not know anything about the chemical and mineralogical composition of the rocks under consideration. The entire region has been intensively studied especially with regard to the mineralogical composition mainly by the team from Greifswald University (see e.g. Schmitz 2008). There are too many sites providing the same outward appearance indicative of different depositional environments including topsoils so that we cannot unequivocally at the moment provide an interpretation resting on a sound and safe platform.
Further reading and more literature cited there on the mineralogy of this type of overburden see:
DILL, H.G. (2017) Residual clay deposits on basement rocks: The impact of climate and the geological setting on supergene argillitization in the Bohemian Massif (Central Europe) and across the globe.- Earth Sciences Reviews 165: 1-58.
With kind regards
H.G.Dill
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I am getting increase value around 16 degree using normal LST model.
Is there any specific method to derive glacier surface temperature?
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Dear all, it would be of interest to compare the performance between single and split-window algorithms. Albeit, considering the issues of TIRS resulting in uncertainties.
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We have some detailed photography of glass fracturing as it is subjected to extreme cold on one edge, used it for calibrating our codes (qualitatively). 
if you goals of your project align with things we are doing perhaps we should collaborate?
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Hi Robert .. Please contact with Dr. Yu-Shu regarding your request. However this project was done end of 2015.
Good luck!
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MWP-1C (Melt water pulse)was termed in Liu et al.,2004.In western pacific area, rapid sealevel rise occured 9.8-9.0ka BP,with the rate nearly 25mm/a. I am eager to konw are there any other geological evidence of rapid sealevel rise at this timespan?
8.2 sealevel jump was attributed to the abrupt collapse of Laurentied Ice sheet and out burst of glacial lakes(Agassia and Ojibway).
So,What's the difference and  connection between  MWP-1C and 8.2 sealevel jump? (timespan, amplitude of sealevel rise, sources of meltwater....)
Thank you very much!
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Melt water pulses MWP 1a, 1b, & 1c were caused by the collapse of ice sheets. The 8,2 ka event was cause by the outflow from glacial lakes caused by the cllapse of a natural dam and was much quicker.
Will the collapse of the Greenland ice sheet produce MWP 2?
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From what I see, gemorpohology of proglacial zones of tropical glaciers has not been a major issue of concern. Together with my students, we're planning a small geomorphological project on Zongo glacier in Bolivia (drone, DEM, gemorphological map). Any publications, maps or more ideas for research would be of great use.
Thanks in advance,
Jakub
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Hi Jakub,
Jacob Yde, a colleague of mine, has just published an article about snow distribution in Andes.Please find the link to his article below.
Cheers
Lukasz 
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The frequency curve is of a clay bed from a valley lake deposit in a mountanous terrain.
extreme care is taken when sampling so mixing of samples may not be the case.
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From the cumulative curve you can measure the percentiles that help you to calculate the grain size parameters. If you want to get an idea on how the different particle size and stocks that help us to know the sources of sediment supply, we must trace the frequency curves (Weight Percent (%) = f (d (phi or mm)). With the presence of several slopes and inflection points on your cumulative curve, it is a multimodal distribution, and we can say that this sediment comes from different areas (sources).
Best regards,
Amor DEGAICHIA
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This is a question that’s been asked for decades. There is always some danger in picking who first asked it, but glaciologist John Mercer in 1968 is a strong candidate. Mass changes in the ice sheet translate into changes in sea level, and a lot of people live close enough to sea level to be displaced if the ice sheet were to be lost, while many more enjoy the beaches and ports that would be affected.
Many things affect sea level. For example, more snow on an ice sheet — as we expect on the Antarctic ice sheet and central parts of Greenland in a warming world — tends to lower sea level by taking water that evaporated from the ocean and storing it on top of an ice sheet. But more melt on an ice sheet — as we expect in parts of Greenland with warming — takes water from the ice sheet and puts it back in the ocean, raising sea level. Melting of mountain glaciers has a similar effect as melting the ice sheet, as does pumping of water out of the ground to irrigate crops or for other uses, because most of that water ends up in the ocean rather than back in the ground. Warming the ocean causes expansion of the water and raises sea level. All of these are interesting and important influences, with notable uncertainties, but we don’t think that those uncertainties are huge.
Another way to raise sea level is for ice sheets to spread more rapidly under their own weight, taking ice from above sea level and delivering it to the ocean to make icebergs. This influence on sea level is complicated, and is where various uncertainties arise. Many factors control how rapidly ice flows, and thus how rapidly ice sheets can transfer land ice to the ocean to raise sea level.
Today, around most of Antarctica and parts of Greenland, the ice reaching the ocean does not immediately break off to make icebergs; instead it remains attached while spreading over the ocean, forming an ice shelf. The ice shelves almost all exist in bays or fjords, and thus have friction with their sides; the undersides of many ice shelves also hit local high spots in the seafloor, generating additional friction. Furthermore, the undersides of the ice shelves, where they are in contact with the ocean, are at their melting point. Warming ocean water tends to thin the shelves — a warming of 1 degree Celsius increases melting by about 10 meters per year — reducing the friction, and thus allowing faster flow of the ice that feeds the shelves, raising sea level.
Various features of the geologic record, modern observations, and investigations with models point to the importance of “threshold” behavior. Increasing the ocean temperature increases the ice’s speed, with the potential that at some high-enough temperature, the speed will jump rather abruptly and irreversibly. Such behavior is especially interesting and important, but also difficult to predict. You can undoubtedly think of many questions: What happens if the water temperature stays the same, but the rate of ocean circulation changes? What about warming adding meltwater into crevasses that could wedge them open and remove the friction that way? If an ice shelf is thinned, by how much does the flow speed increase? What are the thresholds?
A large and vigorous community of scientists in the field, remote-sensing experts, and modelers is working to measure, understand, project, and test the projections. And, we’re doing so with some urgency — we want to get answers in time to provide useful guidance to people making decisions about energy and the environment. 
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There are four lessons here from a course in climate change being run by the University of Exeter which address the future of the cryosphere:
There is also this BBC TV program which ends by discussing the Antarctic cryosphere. It is hosted by David Attenborough, and features a mother polar bear and her cubs (in the Arctic).
https://www.futurelearn.chttp://www.bbc.co.uk/programmes/b00zj39jom/courses/climate-change-challenges-and-solutions/3/steps/60201
I believe that program was not shown in the USA because suggests climate change is not only real but also a major threat to mankind.
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I would like to estimate quantification of error during the glaciers area mapping and I need instruction
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Hi, Levan, I try to answer some aspects of your questions. For an overview of the uncertainties involved in glacier delineation, you can see the Chapter 7 of GLIMS Book which suggested by Dr. Glazovsky, and also some literatures list in its references, like Paul et al (2012). But for the practical assessments of the glacier delineation error, I suggest you use the buffer method that was most widely used in recent years. You can see the paper of Dr. Bolch which was published on Remote Sensing of Environment at 2010 (vol 114, 27-137), or my paper on Journal of Glaciology at this year (vol 61, issue 226, 357-372). 
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I'm studying a body of ice with known thickness (60m) and slope (20°) and need to calculate the rate of strain (i.e., downslope velocity). I can calculate the downslope force of the glacier but I don't have the needed constants (k, A) needed to complete the strain rate calculation following the Glen-Nye Flow Law (strain rate = k*stress^n). Perhaps it is listed in Hooke's 'Glacial Mechanics' or Benn and Evans' 'Glaciers and Glaciation' texts? Thanks in advance, -Josh
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Paterson (now Cuffey and Paterson) "The Physics of Glaciers" 4th ed., Elsevier, 2010, includes discussion of the equation and constants as well as experimental data.  I note that Amazon has free-trial electronic access.
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I have no experience in glaciers modeling, but I think it could be useful in my work. I am considering post LGM deglaciation of subpolar fjord and I have a little information about retreats rates. It would be useful to model deglaciation over ~12 ka in order to get more control points for retreat rates. It is necessary for my numerical experiment with erosion rate (glacier positions are input and are integrated).
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I attached to you four useful articles of methods used in tropical glacier areas, some of those areas had glaciers until 8 ka ago. 
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Do paramo ecosystems depend on glacial geoforms to exist? or can the exist wherever climate conditions are suitable?
I know that due to the variation on temperature given by glacial-intergacial cycles, two process occurs: an altitudinal variability on the bioclimatic floors, generating that paramo ecosystem goes lower or higher depending on the temperature, going lower when is colder and higher when is warmer, the same happens with glaciar environment, the glaciar goes lower when is colder and higher when is warmer.
It is known that in Colombia the maximum extension of glaciar masses was 2400 meters above sea level, and right now due to the temperature conditions paramo ecosystems are located among 3000 meters above sea level, and 4000 meters above sea level, covering old glacial landforms.
but is this a casual relationship between glacial landforms and paramo ecosystems? or there any posibility that paramos has generated a straight relationship with those glacial geoforms?
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Development of glaciers implies a certain altitude, low temperatures and solid precipitation (snow). But also, and this is most important, it requires appropriate relief where snow accumulates and then transformed into glacial ice. Glacial erosion occurs and is further ahead in the area of ice accumulation. As described in the "páramos" are plains, situated at a height suitable to serve accumulation area neve and ice formation. In the area of ice accumulation is expected that there is too much erosion, and thus preserved virtually intact in the postglacial period. Currently the ice has disappeared, and hence the height to which it is located can develop the páramos. In my opinion the glacier area -páramos relationship is real and is essentially due to topography factor.
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Right now I am working on a project with the Bogota Water Company. This company is in charge of water supply for the entire city of Bogotá. The water is taken from Chuza River basin, that is located in Chingaza's paramo. Paramo ecosystems are intertropical montane ecosistems located between 3200 meters above sea level and 4000 meters above sea level, with temperatures ranging between 2C and 17C, the mean annual temperature is 10C. In Colombia, all paramos are located on old glacial landscapes .
The project is about understanding what could happen with the water supply under global warming conditions.
From some fieldwork observations as well as aerial photographs interpretation, I could infer that glacial deposits offer the mot suitable geoforms for water catchment, and water infiltration. Glacial deposits have a high rugosity which is evidenced by the presence of a lot of depressions that concentrates water in small and swallow lakes similar to wetlands. I would like to produce a model, that gives me the water catchment susceptibility and water infiltration susceptibility in terms of geomorphology.
In order to solve this issue, I would like to know if anyone can help me with articles, techniques, methodologies regarding the evolution of glacial and periglacial geoforms under global warming, and regarding the relationship between glacial geoforms and water catchment, as well as glacial geoforms and water infiltration.
I would appreciate any information,
Kind Regards,
Diana Lozano
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Here is my article about glacial forms and disasters, hope it could be useful
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These are common in New England and probably have some value for glacial movement.
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The best explanation is generally thought (as Jan-Michael Lange said above) to be the stick-then-slip pressure-impact cause by embedded rocks in the ice pressing down on the bed. Crescentic fractures and glacial striae are indeed used to deduce glacial-flow directions.  The main knock against them is that they can be time-transgressive as the flow centers of the ice change.  Though very labor intensive, direction change studies (via cross-cutting relationships) can also be useful. The article Kenneth Towe linked above is a good one. Most introductory texts have some information on process (e.g. Ehlers, 1996, Quaternary and Glacial Geology). The attached photo shows both fractures and striae on columnar basalt near Haifoss in Iceland.  Note the ice flow is toward the viewer in the center of the photo but to the left in an older set of striae in the middle left of the photo.
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What are the best methods in Remote sensing and GIS to study the energy balance of a high altitude glacier where we have little or no observational data. 
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Dear Shaktiman, Gomez and Natalia 
Thanks for your help will be in touch with you people
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Current research suggests the possible existence of sporadic permafrost in relation to several buried ice patches of Picos de Europa, with mean annual temperatures close to 0ºC in the debris that cover these relict ice bodies. But so far it has not been demostrated to 100%.
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BTS  measuremets, ground temperatures monitoring at different depths at least 2 years, conducting geophysical investigations (Electrical Resistivity Tomography, GPR).
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I work in Svalbard. Proglacial rivers are shallow (usually up to ca. 50 cm), the expected discharge may reach up to 5 m3/second during extreme conditions, with summer averages of 0.5-1 m3/second. The flow is rather turbulent, sediment transfer is high, including rocks up to 10 cm in diameter. No stable ground is to be found at the sites, only gravel, occasionally washed out during higher water levels. Any additional abilities of such equipment (e.g. autosampling etc.) would be great, but I guess I'm asking too much.
If you have not heard of anything suitable for my needs, maybe you have some ideas how to organize manual discharge measurements so they will not become pain in the back very soon? I need to measure discharge in 3-4 streams, at least every 5-10 days, together 15 km of trekking. Again - what kind of equipment can you recommend?
I would appreciate any tips from more experienced colleagues.
Thanks for your time,
Jakub
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A StreamPro would be great in some respects - it is quick to deploy, it gives rich data. But it really works best in deeper water - you might not get good results in shallow, braided flows. Plus it's quite bulky to transport on foot. But the attached document might help answer some questions.
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New Zealand, North Island, glaciation, glaciers.
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I did some work on this in the late 2000's (see attached). Possibly around 1400m in the Tararua Range (part of the "axial" ranges of the North Island), though with a slight southwest-northeast increase in ELA gradient. On Mt Ruapehu, there are LGM moraines but the record is difficult (though not impossible) to deconvolve, due to the volcanics, high weathering rates, and non-glacial slope deposits. Interesting sites though!
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I want to know the ice sheet or glacier volume (not area) changes in the Tibetan area. Is there any satellite data or mathematical model to calculate the annual change rate, or is there any products already exist?
Many thanks! 
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This would not be easy. Lets assume that you can find satellite data that will give you the differences in areal ice extent over the period of time that interests you. I would think you would want at least over a 10 year period. You then need to to convert this areal change into a volume change. If you are dealing with an icecap such as the Barnes setting on a fairly flat bed this might not be too difficult. In your case I would guess that you are dealing with a fairly mountainous area so that getting a good volume change estimate could be very difficult. I would look at back issues of the Journal of Glaciology to see if a related study has been carried out at some other area. If such a study exists you can build on it and modify it to be as appliable as possibly to your area of interest. Good luck!!
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The rock was found as an erratic boulder in NE Germany (Usedom Island) and most probably comes from Sweden. SW Finland may also be possible though. The individual components are igneous rocks, mostly granites. the rock is part of an exhibition on glacial erratics (Gesteingarten am Forstamt Neu Pudgla) and we would like to add some more information.  Please contact me for more details if you have an idea.
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Hi Gösta,
can you provide some close up pictures from single clasts of this conglomerate?
Best regards
Johannes
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I would also like to know how they are formed, and what is their influence on climate change.
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Besides what Jakub mentioned, 10Be is also used to date erratics left by glaciers and this helps to determined the age of former glacier extent. The idea is that the boulder had no 10Be at the time of deposition and this isotope is later produced by cosmic radiation in the surface layer. Hence, the amount of 10Be is a measure of time. I have included a link to an open access article that described the method in more detail.
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I will be using these instruments on Mt. Everest this spring, to look at albedo changes on snowpack on the ground and comparing from results obtained from orbit. Anticipated range: 6800 - 7500 meters. I'm wondering about battery life, field of view and sensitivity of both instruments.
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The instruments will surely work and will provide you very useful results but the main cause of worry will be battery of these instruments you should keep the batteries in a warm place like pocket of your clothing so that they do not discharge due to the cold.
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The genesis of the Kelleys Island flutes is debated. http://www.ux1.eiu.edu/~cfjps/1300/glacier_photos.html See 15th photo down.
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http://www.hollianneholmes.com/glacialgrooves/ggphotos.html See images under the heading "Photos of the Glacial Grooves in 2012" It has the morphology of pristine extruded soft sediment. Notice the 5th and 6th photo down in particular.
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We mapped bedform fields (drumlins, megalineations, ribbed moraine and hummocky terrain), and flow paths hundreds of kilometers long for most of the Laurentide Ice Sheet. In many cases, flow patterns are coherent over whole fields with pristine subglacial landscapes and little, if any, overprinting. Flow at the lateral margins of fields and paths was parallel to these margins-- if the bedforms were created during orderly retreat of arcuate termini the flowlines would be oblique to the lateral margins. Retreat moraines are extremely rare or absent or relate to extra-flow path glaciers, and there does not seem to be extensive masking of the bedforms by proglacial fans or other deposits. One exception is the appearance in some fields of one or a few very large and extensive glaciofluvial moraines, which do not relate to the patterns of bedforms. Tunnel channels and eskers are common elements of the subglacial landscape. I can only imagine that these characteristics mark bedform creation in a single event (others have made this suggestion), followed by ice-sheet stagnation over areas which may be >100 000 km^2. Any thoughts on this interpretation and its ramifications?
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Hi John
Thanks for your feedback.
I think your response is quite reasonable. This impact to the LIS is just an idea I have been thinking about but have not studied the subglacial evidence and geomorphology systematically.
The impact could have struck part of the LIS and not affect subglacial landforms in another region. Was any of the LIS cold-based? that might provide partitioning of effects of this extraterrestrial impact idea. You could possibly vaporize some of the ice sheet and not disturb the subglacial landforms.
Also, an impact resulting in surges of meltwater from the top of the LIS delivered to
the bottom, could bring about drumlin fields at the time of the event. As the remaining ice decays around these structures, they would be preserved. Just thinking about alternative mechanisms. I think I saw a study on drumlins forming today, in Iceland so you might not need a catastrophe, but on a large scale it might work, particularly since the LIS is no longer with us.
I listed the impact structures that have been found in my first post, and I listed ongoing research into Hudson Bay, St. Lawrence seaway et al pockmark structures.
Wu et al 2013 found microspherules in Pennsylvania that they sourced to Quebecia terrain, and interpet these as ejecta. Many others have published papers in the last few years so the hypothesis is getting support.
Iridium for the KT impact was in amounts of PPB. Ir is not routinely analyzed for in lake sediments, which I what I study.
Petaev et al 2013 found Pt in the Greenland Ice Sheet for YDB. Perhaps we should look for Pt in lake sediments.
If the ice chunks impacted soft sediment during possible meltwater overland runoff, you might not see a rim.
With an ET impact, you could potentially transport ice to the North Atlantic, depending on the angle the impactors struck (speculation of course), without having an outlet from glacial Lake Agassiz, for instance.
Joanne
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I'm a little confused about the inter-changeability of these terms in a marine sedimentation context. My understanding is as follows:
Glaciogenic sedimentation = sedimentation derived from glaciers (or ice-sheets)
Glacimarine sedimentation = sedimentation derived from glaciers (or ice-sheets) that calve directly into the marine environment.
If this is correct then glacimarine sedimentation is a subset of glaciogenic and either of the terms could be used when referring to an ice-sheet that extends into the sea.
Can anybody provide some clarification?
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I don't think you need any clarification, your succinct definition is right on the mark. In "Glacimarine Environments: Processes and Sediments," Dowdeswell and Scourse (1990) defined glacimarine as "all those areas where sediment is deposited in the sea after release from glacier ice (including tidewater ice fronts, floating glacier tongues, ice shelves and icebergs) or sea ice." Since marine basins are more highly represented in the geologic record, even though this can be indeed be considered a subset of glacigenic, it is an important area of study. The book "Climate Modes of the Phanerozoic" (Frakes, Francis, and Syktus, 1992) is full of references to using marine sediments with increases or decreases of ice-carried dropstones as a proxy for ice-volume change.