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Gundu Rao, C.
- Operator Variation in the Estimation of Percentage Heavy Minerals
Authors
1 Department of Geology, Central College, Bangalore, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 2, No 0 (1961), Pagination: 50-60Abstract
Griffiths and Rosenfeld have demonstrated that all experimental procedures are characterised by two sources of error: (i) constant bias distinctive of each operator and (ii) inconsistency within one operator and among a group of operators. An experiment was organised by the writer to evaluate operator variation that may enter in the estimation of percentage heavy minerals by using a large sample of Ariyalur sandstone (Trichinopoly Cretaceous) as an example. This experiment revealed that heavy mineral work also involves, as many other experimental endeavours, sources of error such as (a) experimental (b) operator variation (c) constant bias within individual operators and (d) inconsistency of operators from sample to sample. It is pointed out that if all these sources of error are not properly evaluated, 'isolated and controlled by suitable analysis of variance techniques, the results of heavy mineral work will be far from any real value.- Detrital Dolomite from Ujhani Structural well No. 1 Ganga Valley, India
Authors
1 Institute of Petroleum Exploration, Oil and Natural Gas Commission, Dehradun, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 12, No 4 (1971), Pagination: 377-379Abstract
No Abstract.- Cluster Analysis Approach to the Problem of Facies Classification of the Carbonate Rocks in the Krol Series
Authors
1 Oil and Natural Gas Commission, Dehra Dun, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 11, No 3 (1970), Pagination: 248-252Abstract
The Krol series in the Sub-Himalayas, include six lithological units, namely Infra Krol, Krol A.B.C.D. and E. Among these, A.C.D. and E. incorporate increasing thicknesses of carbonate rocks from A to E, with minor shale intercalations. Cluster analysis of 150 carbonate samples drawn from these four formations in five stratigraphic profiles between Mussoorie and Lansdowne, based on six petrographic attributes, has shown that the samples cluster into four meaningful groups. Interpretation of these groups reveals that the carbonate rocks of the Krol series fall into two broad facies or depositional mechanisms, one Krol A+C, of micrites and sparites, and the other, Krol D+E of calcicdolo and dolocalcicmicrites, and their variants. The earlier classification of Krol carbonates into four lithological units, A.C.D and E, from a facies point of view, seems to be unjustified. The depositional mechanism of A+C is succeeded by Krol D+E in the vertical profile. This supports the earlier view of Rao that the Krols represent a phase in the development of a basin centre evaporite sequence.- Corrensite from the Sirban Limestone of Riasi Jammu and Kashmir State, India
Authors
1 Institute of Petroleum Exploration, Dehra Dun, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 14, No 2 (1973), Pagination: 193-196Abstract
No Abstract.- Interspecific Association of Heavy Minerals and its Application in Comparison of Strata and Provenance Studies
Authors
1 Institute of Petroleum Exploration, Oil & Natural Gas Commission, Dehra Dun, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 16, No 4 (1975), Pagination: 465-469Abstract
Interspecific association means the significant association of heavy minerals due to more than chance causes alone. p-F multivariate model helps in establishing significant associations among heavies estimated from a set of samples. Attempts are made to analyse three sets of samples of Lower, Middle and Upper Siwaliks from a vertical profile in the Punjab. Application of the method in comparison of strata and provenance studies is discussed.- Late Diagenetic Solution Seams and Flaser Structures in the Carbonate Reservoir Rocks of Bombay Offshore, India
Authors
1 Institute of Petroleum Exploration, Oil and Natural Gas Commission, Dehra Dun, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 20, No 3 (1979), Pagination: 128-131Abstract
Solution or flaser seams are of common occurrence in many producing carbonate reservoir rocks of Bombay Offshore, India. The flasers are simple or composite and characterise many poorly to semi-Iithified Iimemuds. The flasers are wavy, undulating, horizontal, inclined or vertical lines, random whisps, horse tails, branching and combining, combining with groups of simple seams enveloping limemud lenses and nodules. Lithological and petrographic evidence suggest that the flasers are of late diagenetic compactional solution origin. Closely spaced flasers may have contributed considerably to the permeability of the reservior rocks and thus facilitated good production obtained from many Bombay offshore wells.- Diagenesis of Larger Foraminifera (Lepidocyclina, Sp.) and its Effect on Porosity in the Limestone Reservoir Rocks of Bombay Offshore Area
Authors
1 Institute of Petroleum Exploration, Oil and Natural Gas Commission, Dehra Dun, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 19, No 4 (1978), Pagination: 165-168Abstract
The tests of the larger benthonic foraminifera (Iepidocyclina, sp.) in the limestone reservoir rocks of Bombay Offshore area show various progressive stages of diagenetic alteration, starting from the initial stage of the pillars and septae of the test being clarified to aggregates of microfibrous calcite enclosing polygonal areas suggestive of original chambers, to tests completely rendered to aggregates of fibrous calcite proceeding as parallel brush like rays from the axial plane of the test, with the total destruction of its original Skeletal morphology. Evidence is put forward to show that the sheaf like bundles of radiating fibrous spar are of pore filling and syntaxial overgrowth origin than one of aggradational neomorphism. In calcarenitic rocks of such foraminiferal assemblages excessive overgrowth cementation may remove original intergranular porosity, thus reducing considerably the oil and gas reservoir capacity of the rocks.- Comparison of Porosity in Carbonate Petroleum Reservoir Rocks of Bombay Offshore
Authors
1 Institute of Petroleum Exploration Oil and Natural Gas Commission, Dehra Dun, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 20, No 7 (1979), Pagination: 364-366Abstract
In carbonate rocks porosity is of varied origin, subsequently modified, destructively or constructively by several stages of diagenesis. The ultimate porosity of a carbonate reservoir rock is an algebraic sum of all these processes. As a result, porosity in carbonate rocks varies over very short distances both horizontally and vertically. A partial solution to this problem of evaluating porosity variations may be had by generating and comparing frequency distributions of porosity over neighbouring wells. The method is illustrated by comparing porosities of two wells from Bombay offshore area by the simple non-parametric Kolmogrov-Smirnov distance or 'D' statistic. By this method it is shown that Bassein 3 and South Bassein well No.1 are significantly different; further, it is shown that South Bassein well No.1 has a better porosity development than Bassein well No.3. Kolmogrov-Smirnov' D' statistic is an universal one and must find favour among Petroleum Engineers and Reservoir Geologists.- Dimensional Orientation of Micrite Particles and Lithification in L-3 Carbonate Reservoir Rocks of Bombay High Oil Field, India
Authors
1 Institute of Petroleum Exploration, Oil and Natural Gas Commission, Dehradun, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 21, No 4 (1980), Pagination: 199-203Abstract
Thin bands of lithified biomicrites separate highly leached, poorly to semilithified biomicrite reservoir rocks of the L-3 zone of Bombay High Oil FIeld. Among many criteria suggested in literature as to the lithification of limernuds, percolation of carbonate ion bearing solutions principally across and secondarily along the bedding plane appears to account for most of the lime cement. This concept is tested by a dimensional orientation analysis of micrite particles. This indication suggested that Iithifying solutions have preferentially moved basically at right angles and secondarily parallel to the bedding plane.- Dolomitisation of Micritic Limestones in Deeper Water Proterozoic Limestone-Shale Alternations, Larji Window, Lesser Himalayas, Northwest, India
Authors
1 Department of Geology, Dharam Samaj College, Aligarh 202 001, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 28, No 5 (1986), Pagination: 421-426Abstract
The dun pink micritic limestone and purple shale alternations unit resemble the deeper Water carbonates. The dull pink micritic limestones of the unit give a weak 1:4 dilute acid reaction and negative test for Mann's stain solution for dolomite. Despite this, the samples showon XRD Charts, a prominent peak for ordered dolomite (104) 2.88 Å to the total exclusion of calcite. The important point of the present example is, despite complete dolornitisation, the resulting dolostone neither shows change in porosity nor in size and shape of the micritic particles. The kind and intensity of dolomitisation observed in the present example are difficult to explain in terms of the existing dolomitisation models for deeper water limestones.- Oolites from the Krol Group of Lesser Garhwal Himalaya: An Ancient Analog of Modern Dead Sea Hypersaline Coated Grains (Oolites)
Authors
1 Department of Geology, D. S. College, Aligarh 202 001, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 27, No 2 (1986), Pagination: 209-213Abstract
The oolites occurring at the top of Krol 'C' limestones in the Krol Group of Garhwal Himalaya, Uttar Pradesh, resemble in shape, size and internal structure, the Modern Dead Sea hypersaline coated grains (oolites). The finding of the analog of Modern Dead Sea Type hypersaline oolites at the top of Krol 'C' litho-unit seems to lend support to the earlier conclusion that the Krol Group in this part of Lesser Himalaya may represent a basin centre evaporite sequence.- Flat Stratification from a Quartzarenite Unit of Lower, Upper Proterozoic (Lower Vindhyan) Age, Larji Window, (Lesser Himalaya), Kulu District, Himachal Pradesh, India
Authors
1 Department of Geology, D. S. College, Aligarh 202001, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 28, No 1 (1986), Pagination: 54-57Abstract
The pink Quartzarenite Unit 3 (Q3) of Larji Window Section (Lesser Himalaya), Kulu District, Himachal Pradesh, India, shows a lower thickness of continuous, undisturbed, uniform, horizontal laminations followed by a zone of flat stratification and this in turn by cross-bedded layers. Horizontal stratification is referred to as due to high flow regime conditions and the cross stratification to moderately shallow upper part of low flow regime conditions. Flat stratification (crenulated or wavy laminations of low amplitudes and broad wave lengths) are commonly observed in flume experiments as a function of low flow regime in shallow water formed by the migration of very small ripples or very shallow sand waves but rarely reported from the stratigraphic record. The only known two instances are from Bull Run Formation (Triassic) of Northern Virginia and Duncannon Formation (Devonian) of south-central Pennsylvania. In this connection, reporting the occurrence of flat stratification from such an ancient quartzarenite unit (Lower Upper Proterozoic) as of Larji Window may be of considerable interest from the point of view of Dynamic Stratigraphy.- The Thermal History of Sedimentary Basins: Methods and Case Histories
Authors
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 34, No 5 (1989), Pagination: 546-547Abstract
No Abstract.Full Text
- Clastic Depositional Sequences: Processes of Evolution and Principles of Interpretation
Authors
1 16, 1st Cross, Srirampuram P.O. Bangalore 560021, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 35, No 5 (1990), Pagination: 543-544Abstract
No Abstract.- Carbonate Sedimentology
Authors
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 37, No 1 (1991), Pagination: 90-90Abstract
No Abstract.- Physical Principles of Sedimentology
Authors
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 36, No 6 (1990), Pagination: 675-675Abstract
No Abstract.- Clay Sedimentology
Authors
1 Bangalore, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 35, No 3 (1990), Pagination: 316-316Abstract
No Abstract.- Siliceous Deposits of the Tethyss and Pacific Regions
Authors
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 35, No 3 (1990), Pagination: 320-321Abstract
No Abstract.- The Petroleum System-Status of Research and Methods
Authors
1 Geological Society of India, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 36, No 5 (1990), Pagination: 549-549Abstract
No Abstract.- Depositional Controls, Distribution, and Effectiveness of World's Petroleum Source Rocks
Authors
1 No Abstract., IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 37, No 3 (1991), Pagination: 309-309Abstract
No Abstract.- Sedimentology
Authors
1 Bangalore, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 37, No 5 (1991), Pagination: 503-503Abstract
No Abstract.- Fundamentals of Geology
Authors
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 37, No 6 (1991), Pagination: 604-604Abstract
No Abstract.- Princlples of Sedimentary Basin Analysis
Authors
1 Bangalore, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 38, No 1 (1991), Pagination: 104-105Abstract
No Abstract.- Whither Archaean Graywackes: A Note
Authors
1 2628/1294, 1st Cross, Ram Mohanpuram, Srirampuram P.O Bangalore 560 021, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 38, No 3 (1991), Pagination: 338-340Abstract
No Abstract.- Sandstone Petroleum Reservoirs
Authors
1 Bangalore, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 38, No 2 (1991), Pagination: 215-216Abstract
No Abstract.- Sedimentary Basins of India; Tectonic Context
Authors
1 Bangalore, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 38, No 5 (1991), Pagination: 544-545Abstract
No Abstract.- A Turbidite Limestone-Shale Rhythmite of Sirban Limestone of Raisi, Northwest India
Authors
1 Department of Geology, D. S. College, Aligarh 202001, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 39, No 2 (1992), Pagination: 155-161Abstract
The couplet thickness of Raisi limestone-shale rhythmite is trend-free and non-oscillatory. The couplet thickness are log-normally distributed. These characters suggest, Raisi rhythmite is of episodic as against diagenetic and seasonally-controlled origin of the rhythmites. Among the options available for episodic origin (inundites. tempestites, turbidites) evidences suggest a turbidite origin for Raisi rhythmite.Keywords
Sirban Limestone, Rhythmite, Sedimentology, Turbidite, NW India.- A Mathematical Approach to the Petrogenesis of the Upper Siwalik Conglomerates (L. Pleistocene) of the Jammu Region, Northwest India
Authors
1 Department of Geology, Jammu University, Jammu, Tawi 180001, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 39, No 3 (1992), Pagination: 223-228Abstract
In sedimentary petrography, interpretation of the source and process from the response data i.e., characteristics of the deposited sediment is a convention. The best suited mathematical technique in such an exercise is 'Principal Component Analysis'. Applying this technique to the Upper Siwalik Conglomerates of Jammu region, northwest India (Lower Pleistocene, Cromerian) five components were extracted representing 68% of total variation in the conglomerate system. Components C1, C2 and C4 were identified with erosion and transporting processes (size, size sorting and shape), C3 with composition (quartzite and sandstone pebble proportions) and C5 with depositional processes (orientation and packing). Also, the analysis suggests that instead of three values of each of size and size sorting, and four values of shape used in the investigation, one measure of each of size, size sorting and shape is quite sufficient to explain the total variation in the petrographic properties of the Upper Siwalik Conglomerates of Jammu region.Keywords
Siwalik Conglomerates, PrincipalComponent Analysis, Jammu.- Pebble Count (Modal) Analysis of Four Outcrops of the Upper Siwalik Conglomerates of the Jammu Region, Northwest India and their Textural Implications
Authors
1 Department of Geology, Jammu University, Jammu 180 001, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 40, No 2 (1992), Pagination: 179-190Abstract
The pebble count data from the four outcrops of the Upper Siwalik Conglomerates of the Jammu region, northwest India are compared with the results expected from appropriate theoretical models of constant probability of occurrence from point to point. The resulting degree of fit is applied to characterise the textural arrangement of each constituent.
The experiment shows that within an outcrop for Jarger pebble counts the Positive Binomial and for lower counts Poisson are the appropriate theoretical models. For the combined data over the four outcrops, the proper models are Lexian and Lexian Poisson. This would suggest at anyone outcrop, 5, 10, or 100 pebble counts obtained from anywhere in the outcrop would yield unbiased sample estimate of the outcrop population parameter. Over many outcrops, however, the results are inconsistent. Combined distributions for the four outcrops indicate heterogeneity in the distribution of the variates. Therefore, it is suggested that no one outcrop or one sample from an outcrop represents the entire target population (Upper Siwalik Conglomerates of the Jammu region). The population has to be sampled regionally over several outcrops preferably over an orthogonal grid spread over the target population. The results also suggest that at anyone outcrop the process responsible for the deposition of the conglomerates is uniform but has varied from place to place thus suggesting more than one episode in the deposition of the conglomerates. One has to explain this multi-episodic deposition by a sedimentation model that would explain adequately the quantitative variability present in the data.
Keywords
Siwalik Conglomerates, Jammu Kashmir Himalaya, Analysis of Variance.- Clay Mineralogy of the Carbonate Rocks of the Shali Series (Lower-Upper Proterozoic) of Larji and Shali Windons, Lesser Himalaya
Authors
1 Department of Geology, D. S. College, Aligarh 202001, IN