Title of Invention

METHOD OF RETRIEVAL OF THIN FLEXIBLE PEELS OF CLASTIC SEDIMENTS

Abstract

The invention relates to a method of retrieval of thin flexible peels of clastic sediments from finer grained terrigenous clastic sediments. An emulsion of polyvinyl acetate and polyvinyl alchol ( in 1:1 proportion by wt.) in water is made. This emulsion is poured and uniformly spread on the planed-off surface of the sediment. Dilution depends on the nature of the sediment. For silty sediments higher dilution is used. Depending on the permeability of the sediment one has to try with different dilutions for getting perfect results. When the dilted emulsion has seeped through the surface, a cloth net is placed over the surface and again thicker emulsion is poured over the cloth net or the binder. Dilute Formic acid (N/10) is added drop by drop to the freshly prepared surface and the emulsion is allowed to evenly mix with the acid. Time of curing is 24 hours under normal room temperature. The cloth net along with the adhering sediments can be taken out from the rest of the sample and can be washed to remove the loose sediment.

Full Text

The invention relates to a method of retrieval of thin flexible peels of clastic sediments from finer grained terrigenous clastic sediments. The concept of emp]oying sedimentary structures, both physical and biogenic, in interpreting palaeo-environment is an integral part of the sedimentologists totality of approach.For studying details of these structures as well as the degree of bioturbation, emphasis has been laid on peeling of sediments. Importance of Peeling: Peeling techniques help identifying various micro-structures developed in a particular sequence of sedimentation in any modern depositional environment. By processing a large number of samples and analyzing structures present in them one can get a clear idea about the assemblage of structures formed in a particular environment. This, in turn, help identifying the depositional environment, i.e. whether marine or terrestrial, in rock records. Prior Art Traditional peeling with epoxy resins ( mostly CIBA araldite/hardener combination) requires oven-drying of the sample prior to pouring of the epoxy resins on the dry, warm planed off surface. Therefore, cored sediments are generally brought to the laboratory for drying, and extrication- of peels from them in the laboratory is - 2 - sometimes limited by financial and physical resources. Furthermore, long transportation of boxed cores with silty sediments might lead to destruction of structures. There are disadvantages associated with the present system of preparing sedimentary structures. One of the main disadvantages with the present system is that for better retrieval of sedimentary structures, drying of sediment surface to be peeled off, is required, as these cored sediments are soaked with water. Another disadvantages with the present system is that cored sediments are brought to laboratories for drying, and bringing undisturbed cores from, the field and extrication of peels from them in the laboratory is sometimes limited by financial and physical resources. Yet another disadvantages with the present system is that long transportat Lon of box cores with silty sediments leads to distortion of sedimentary structures due to liquefaction. Reduction of original permeability through compaction also comes about. Further disadvantages with the present system is that peeling through standard method of epoxy casting through oven drying method involves loss of materials and disposal of a large number of peels retrieved by epoxy resin brings environmental hazards. Therefore the main object of the present invention is to propose an easy and cheap method of retrieval of thin flexible peels of clastic sediments from finer grained terrigenous clastic sediments which would be beneficial if the peeling operation could be executed in the field itself. If radiography of sediments is not - 3 - possible abroad a ship for the identification of bioturbated zones in deep sea cores, peeling is essential. Another object of the present invention is to propose a method of retrieval of thin flexible peels which does not require oven - drying of sediments as a pre-requisite for peeling and can be prepared in the field or aboard a ship. This helps identification of the zone of bioturbation in deep - sea cores which is an essential requirement for sampling deep sea sediments. Yet another object of the present invention is that because of the flexible nature of the peels, these can be easily transported from the field without having any fear of getting broken. Further object of the present invention is that disposal of such peels does not create high environmental pollution. Such a combination of mixture can also be used against corrosion of buildings. According to this invention there is provided a method of retrieval of thin flexible peels of clastic sediments from finer grained terrigenous clastic sediments comprising the following process steps: a) box coning with Senckenberg peel boxes; b) the core box is then placed horizontally for the settlement of finer grained sediments; c) the surface to be peeled off is then smoothened with a trowel or a knife; d) an emulsion prepared from chemicals like polyvinyl acetate and polyvinyl alcohol in a proportion of 1:1 by weight and water is poured and uniformly spread on the planed-off surface; - 4 - e) the diluted emulsion is allowed to seep through the sediments and then a calico cloth net is placed over and a thicker emulsion is again spread over this binder; f) Formic acid is added drop by drop on the freshly prepared surface and the emulsion is allowed to be evenly mixed; g) the surface thus produced is allowed to remain undisturbed for drying for 24 hours under normal room temperature; h) the calico cloth net along with the adhering hardened sediments are then taken out from the main core and is washed with water to remove loose sediments. The nature of the invention, its objectives and further advantages residing in the same will be apparent from the following description. In accordance with the present invention a cheap and handy method of retrieval of thin flexible peels from finer grained terrigeneous clastic sediments has been developed. Although this method does not bring out the fineness of the sedimentary structures as one would get in resin casting a large number of peels can be obtained with a limited budget. This, in turn, will help to analyse sedimentary structures statistica1ly. The novelty of the present invention lies in the fact that it is cheap., and can be easily done in the field, even for those coastal areas where there is no power supply. Since peels taken out with this method do not come out as hard slabs, they can be easily transported from the - 5 - field without any apprehension of damage, and one can take many more peels to have a better comprehension about the depositional environment. Furthermore, disposal of such peels will not create high environmental pollution. After box coning, with the help of "Senckenberg" peel boxes, the core box is placed horizontally for some hours for the settlement of finer-grained sediments. The surface to be peeled off is smoothened with trowel or a knife. An emulsion is prepared from few chemicals like polyvinyl acetate and polyvinyl alcohol (in 1:1 proportion by wt.)in water. This emulsion is poured and uniformly spread on the planed-off surface of the sediment. Dilution depends on the nature of the sediment. For silty sediments higher dilution is used. Depending on the permeability of the sediment one has to try with different dilutions for getting perfect results.Different dilutions varying between 1:b and 1:10 (emulsion:water) areused. When the diluted emulsion has seeped through the sediments, a calico cotton net is placed over the surface and again thicker emulsion is poured over the cloth net or the binder. Another chemical dilute Formic acid (N/10) is added to the freshly prepared surface drop by drop and the emulsion is allowed to be evenly mixed with the acid. The surface thus produced is allowed to remain undisturbed for drying. Time of curing is 24 hours under normal room temperature. The cloth net along with the adhering hardened sediments are later on taken out from the rest of the sample and is washed with water to remove loose sediments. - 6 - The chemical reaction involved in this process: The chemical process involved between the emulsion and formic acid suggesting a reaction between acid and alcohol of the polymeric chains leading to cross-linking process has not been detected earlier. A molecule of formic acid might have undergone esterification with the alcoholic (OH) group of one polyvinyl alcohol chain. However, there is also a possibility of a weak hydrogen bond formation between the OH group of a second polyvinyl alcohol chain and the C=0 moiety of the formic acid group. This would imply inter-chain cross linking involving the PVA molecule which may be responsible for the hardening of the sand layer. The reaction between polyvinyl acetate and formic acid may also proceed through a similar mechanism in which the acetate groups may be supported to be hydrolyzed in the presence of formic acid followed by condensation reaction giving an inter-chain cross linked product. It is suggested that in the presence of HCOOH hydrolysis of the polyvinyl acetate takes place. No special Plant and Machinery is required. Few containers for keeping these raw materials and pouring the raw material on the surface. Cost of product of a 12" x 10" peel will be about 30% to 40% of the cost of similar 12" x 10" peel of Epoxy Resin. The invention described hereinabove is in relation to non-limiting embodiments and as defined by the accompanying claims. - 7 - -8-WE CLAIM: 1. A method of retrieval of thin flexible peels of clastic sediments from finer grained terrigenous clastic sediments comprising the following process steps: (a) box coring with Senckenberg peel boxes; (b) the core box is then placed horizontally for the settlement of finer grained sediments; (c) the surface to be peeled off is then smoothened with a trowel or a knife; (d) an emulsion prepared from chemicals like polyvinyl acetate and polyvinyl alcohol in a proportion of 1:1 by weight and water is poured and uniformly spread on the planed-off surface; (e) the diluted emulsion is allowed to seep through the sediments and then a calico cloth net is placed over and a thicker emulsion is again spread over this binder, (f) formic acid is added drop by drop on the freshly prepared surface and the emulsion is allowed to be evenly mixed; (g) the surface thus produced is allowed to remain undisturbed for drying for 24 hours under normal room temperature; (h) the calico cloth net along with the adhering hardened sediments are then taken out from the main core and is washed with water to remove loose sediments. 2. A method of retrieval of thin flexible peels as claimed in claim 2 wherein the dilution is fixed according to the nature of the sediment -9- 3. A method of retrieval of thin flexible peels as claimed in claims 2 and 3 wherein depending on permeability of the sediment different dilutions in the range of 1:5 to 1:10 are fried out for getting results. 4. A method of retrieval of thin flexible peels as claimed in claims 2 to 4 wherein for silty sediments higher dilution is used. 5. A method of retrieval of thin flexible peels as claimed in claim 1, wherein the said formic acid in step (f) is dilute Formic acid (N/10). 6. A method of retrieval of thin flexible peels as claimed in claim 1, wherein the drying time for step (g) is 24 hours under normal room temperature. 7. A method of retrieval of thin flexible peels of clastic sediments as herein described. The invention relates to a method of retrieval of thin flexible peels of clastic sediments from finer grained terrigenous clastic sediments. An emulsion of polyvinyl acetate and polyvinyl alchol ( in 1:1 proportion by wt.) in water is made. This emulsion is poured and uniformly spread on the planed-off surface of the sediment. Dilution depends on the nature of the sediment. For silty sediments higher dilution is used. Depending on the permeability of the sediment one has to try with different dilutions for getting perfect results. When the dilted emulsion has seeped through the surface, a cloth net is placed over the surface and again thicker emulsion is poured over the cloth net or the binder. Dilute Formic acid (N/10) is added drop by drop to the freshly prepared surface and the emulsion is allowed to evenly mix with the acid. Time of curing is 24 hours under normal room temperature. The cloth net along with the adhering sediments can be taken out from the rest of the sample and can be washed to remove the loose sediment.

Documents:

02353-cal-1997-abstract.pdf

02353-cal-1997-claims.pdf

02353-cal-1997-correspondence.pdf

02353-cal-1997-description(complete).pdf

02353-cal-1997-description(provisinal).pdf

02353-cal-1997-form-1.pdf

02353-cal-1997-form-2-1.1.pdf

02353-cal-1997-form-2.pdf

02353-cal-1997-form-5.pdf

02353-cal-1997-form-6.pdf

02353-cal-1997-gpa.pdf