Glaciogenic Reservoir Analogue Studies Project
Encyclopedia
The Glaciogenic Reservoir Analogue Studies Project (GRASP) is a research group studying the subglacial to proglacial record of Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....

 glacial events. It is based in the Delft University of Technology
Delft University of Technology
Delft University of Technology , also known as TU Delft, is the largest and oldest Dutch public technical university, located in Delft, Netherlands...

.

Introduction to glaciogenic reservoirs

Glaciogenic reservoirs are sedimentary rocks deposited under an ice sheet influence and that are involved into a gaz or oil reservoir
Oil reservoir
A petroleum reservoir, or oil and gas reservoir, is a subsurface pool of hydrocarbons contained in porous or fractured rock formations. The naturally occurring hydrocarbons, such as crude oil or natural gas, are trapped by overlying rock formations with lower permeability...

. The glacial earth system is complex to study. A large amount on past and ongoing scientific programs work(ed) on our cryosphere
Cryosphere
The cryosphere is the term which collectively describes the portions of the Earth’s surface where water is in solid form, including sea ice, lake ice, river ice, snow cover, glaciers, ice caps and ice sheets, and frozen ground . Thus there is a wide overlap with the hydrosphere...

 and generate a lot of debate about its dynamic, sustainability and behavior against climate change
Climate change
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...

s. Past glaciations or ice ages record occurred several times (Timeline of glaciation
Timeline of glaciation
There have been five known ice ages in the Earth's history, with the Earth experiencing the Quaternary Ice Age during the present time. Within ice ages, there exist periods of more severe glacial conditions and more temperate referred to as glacial periods and interglacial periods, respectively...

) along the geological time scale. As they are hundreds of million years old, these ancient glaciations are even more hard to analyse and study. Earth at that time had a different atmosphere composition, the chemistry of the oceans was also different, life evolution on earth had also a great impact on the dynamic of these ice sheets, the continents were in a particular setting, etc. Geologists have a broad idea of all those parameters but glaciologists know that this is the combination of those setting that bring to our current ice-age.
A glacial system is able to produce a very large amount of sediment due to the tremendous erosive forces of ice at its base. Those sediments are particularly coarse-grained (principally sandstones and conglomerates) and produced in consequent volumes http://www.bgr.de/ecord/index.html?/ecord/basins/basins_focus.htm. For their good reservoir properties, ancient glacially-related sediments have been targeted by oil industries. They are currently massively exploited in North Africa, in the Arabic peninsula, South Africa, and few small fields are present in Asia, Australia and Northern Europe. The main ice ages concerned are the Late Ordovician glaciation (Hirnantian
Hirnantian
The Hirnantian is the seventh and final internationally-recognized stage of the Ordovician Period of the Paleozoic Era. It was of short duration, lasting about 1.9 million years, from 445.6 ± 1.5 to 443.7 ± 1.5 Ma . The early part of the Hirnantian was characterized by cold temperatures, major...

) and the Permo-Carboniferous
Permo-Carboniferous
The Permo-Carboniferous refers to the time period including the latter parts of the Carboniferous and early part of the Permian period. Permo-Carboniferous rocks are in places not differentiated because of the presence of transitional fossils, and also where no conspicuous stratigraphic break is...

 glaciations.

Project objectives


Analogy
Analogy
Analogy is a cognitive process of transferring information or meaning from a particular subject to another particular subject , and a linguistic expression corresponding to such a process...

 is a usual geologist method, using the present day observations and project/adapt it to the ancient earth systems. The main problem of this technique is the time-scale considered and the observation methods used. Most of the time, observations of active ice-sheet processes are instantaneous at geological time-scale and hard to apply in the ancient. Furthermore, in the ancient, field and geophysical studies are carried out at lower resolution but on a wider scale (time and space). Finally, even if Subglacial lake
Subglacial lake
A subglacial lake is a lake under a glacier, typically an ice cap or ice sheet. There are many such lakes, with Lake Vostok in Antarctica being by far the largest known at present.-Characteristics:...

s are observed bellow ice sheets, melt-water drainage system processes ongoing, especially like the tunnel valley
Tunnel valley
A tunnel valley is a large, long, U-shaped valley originally cut under the glacial ice near the margin of continental ice sheets such as that now covering Antarctica and formerly covering portions of all continents during past glacial ages....

s remain unobserved directly. The record of these huge subglacial "rivers" is mainly analysed via the recent ice ages imprints (Weichselian, Saalian and Pre-Illinoian or Elsterian stages) and in the ancient one (Late Ordovician and Permo-Carboniferous
Permo-Carboniferous
The Permo-Carboniferous refers to the time period including the latter parts of the Carboniferous and early part of the Permian period. Permo-Carboniferous rocks are in places not differentiated because of the presence of transitional fossils, and also where no conspicuous stratigraphic break is...

)

The idea of GRASP is to use methods commonly applied in the ancient onto recent glaciation record (Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....

). In the ancient, wide datasets are acquired by oil companies during exploration of sedimentary basin
Sedimentary basin
The term sedimentary basin is used to refer to any geographical feature exhibiting subsidence and consequent infilling by sedimentation. As the sediments are buried, they are subjected to increasing pressure and begin the process of lithification...

s. By using the same type of data for the Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....

 glacial record, the project tries to generate data comparable in between ancient and recent glaciations. The studied area is the North Sea
North Sea
In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean. In the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively...

 that was glaciated during the Last Glacial Maximum
Last Glacial Maximum
The Last Glacial Maximum refers to a period in the Earth's climate history when ice sheets were at their maximum extension, between 26,500 and 19,000–20,000 years ago, marking the peak of the last glacial period. During this time, vast ice sheets covered much of North America, northern Europe and...

 as well as the Northwestern Europe. On the sea floor, around the North Sea and into the kilometre of sediments bellow, many traces and evidences of the glacial events are recorded. As this place is a petroleum province, many data, especially geophysics ones are currently released or could be borrowed for academic purposes.

So, by joining the skills of three different universities, with the help of many data providers and the funding of six oil companies, new income is made into the knowledge of paleo-glacial systems. Basin analysis containing geophysical, reservoir and sedimentological models are produced in a new way and in a new type of environment. In an economic point of view, oil companies are interested in these models to have comparable data with their oil fields. In an academic one, understanding the recent ice sheet dynamic and is associated subglacial meltwater flow is crucial in the context of climate change
Climate change
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...

s or fundamentally solving the intricate glacial record equation of recent and past ice ages.

External links

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