bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heavy Mineral Investigations in the Siwaliks of Mohand, District Saharanpur, Uttar Pradesh, India
Authors: Sinha R. N. 
Published: November 2024

Abstract
The Mohand anticline located south of Dehra Dun (U.P.) exposes the middle and upper Siwaliks (Sarmatian to Cromarian). The lower Siwalik was encountered in a deep well, a little south of Mohand.
The middle and upper Siwalik sediments are classified into two (A and B) and three (C, D and E) groups respectively on the basis of heavy mineral suites. The suite of group A consists of garnet, tourmaline, epidote, staurolite, and kyanite besides minor quantities of sphene, rutile, chloritoid, and monazite, and fairly abundant ore minerals (magnetite, hematite, limonite, pyrite and chromite?). Kyanite is marker for group A. Addition of hornblende to the above assemblage marks the suite of group B, and that of hornblende and sillimanite, the suite of group C. The suite of group D is characterized by flooding of ore minerals,. impoverishment of nonopaque minerals, very low garnet and very rare kyanite, and rounded zircon as well as tourmaline. The suite of group E is comparatively richer than that of group D. It mainly consists of very low garnet, rare but persistent sillimanite and abundant kyanite.
The absence of mineral markers in older rocks e.g., that of sillimanite in middle Siwalik and kyanite in lower Siwalik does not seem to be a function of intrastratal solution effects. Alternatively, it is concluded that their appearance was due to uplift and successive unroofing of more metamorphosed rocks constituting the provenance.
The heavy mineral suite of Siwaliks exposed along the Himalayan foothills vary from area to area. The suite of lower Siwalik extending from Jammu to eastern Uttar Pradesh is characterised by presence of staurolite marker and is similar throughout and consitutes a terrigenous mineral super-province. The suite of middle Siwalik sediments varies from area to area and the diversities are ascribed to splitting of the super-province into three provinces extending from Jammu to the Yamuna river, the Yamuna river to the Ganga river, and the Ganga river to Mithawali fault. The mineral province extending from Jammu to the Yamuna river gave rise to two sub-provinces extending from Jammu to the Markanda river and the Markanda river to the Yamuna river during the deposition of upper Siwalik sediments. The respective provinces are delimited by faults presently occupied by the Markanda, Yamuna and Ganga river courses. Tectonic activities along these faults in relation to post-Miocene, Himalayan orogeny vis-a-vis evolution of Siwalik lithotypes requires detailed analyses and, together with the recognition as well as definition of provinces, appears a necessary prerequisite for attempting any regional correlation on the basis of heavy minerals.
The heavy mineral suites of Siwalik rocks exposed in Mohand Anticline are not wholly comparable to those of Jammu, Punjab and Tanakpur (U.P.).
Rare-Earths and Other Trace Elements in Uraninites
Authors: Sankaran A. V. , Bhattacharyya T. K. , Dar K. K. 
Published: November 2024

Abstract
Abundances of the lanthanides, yttrium, scandium and 12 other elements in pegmatitic and hydrothermal uraninites from India and Massif Central, France, are presented and compared with those available in literature. The pegmatitic uraninites exhibit a selective, and the hydrothermal types a complete rare-earth assemblage with Gd markedly high in both. The La-Nd: Sm-Ho: Er-Lu ratio may serve as an index of fractionation. Pegmatitic uraninites show an abnormal distribution of La in excess of Ce. An explanation is offered for this.
Some Problems of Precambrian Geology of the Central and Southern Aravalli Range, Rajasthan
Authors: Sen Saurindranath 
Published: November 2024

Abstract
In the Aravalli Range and its environs, the Precambrians consist of the Delhi and the Aravalli systems with the underlying Banded Gneissic Complex (BGC) regarded as the 'Basement Complex' of the region and correlated with the Bundelkhand Gneisses. The unconformity below the Delhis is described as a 'spectacular hiatus', a fact not apparent in the region under review. Portions of the unit mapped as basal conglomerate have been found to be feldspathized mylonites, though there are stretches of basal grits and conglomerates, especially along the northwestern border with the Pre-Delhis. BGC occurs in four patches: (1) N. of the Aravalli metasediments (BGC I), (2) S. of the Aravallis (BGC II), (3) E. of the Aravallis (Berach Granite), and (4) in an oval inlier below the Aravallis, around Serera. The Aravalli-BGC I boundary is diffuse and indefinite, and was obviously unrecognizable north of latitude 25040'. The boundaries of the Aravallis with the BGC II and the Berach Granite are unconformable, so also is the Aravalli-BGC boundary in the Serera inlier. The correlation of Berach Granite and Bundelkhand Gneiss, though deeply entrenched in literature, is only of a tentative nature. The existence of the Raialos seems doubtful.
The Delhis show three sets of superposed folds: F1 represented by megascopic folds mainly, and in the complex map pattern at times, is rotated by the immediately following F2 along a coincident or nearly parallel axis; a comparatively open and broad F3 cuts them at high angles producing simple interference in the regional pattern. The nature of the fault between the Delhis and the Pre-Delhis along the eastern border is not clear. No structures could be recognized in the small areas of Aravallis and BGC country studied, that could be regarded as diagnostic of the systems. They show the same structures in the same sequence as found in the Delhis. Search for a diagnostic orogenic trend' in small sample areas is beset with difficulties and may be positively dangerous. Only a detailed and extensive mapping could establish such a feature.
The radiometric ages available for rocks of this region are not many. At times contradictory, it is not clear in most of the cases if these 'ages' really date an event to be correlated with the relevant orogeny. A scheme of Precambrian stratigraphy of Rajasthan is proposed, based mainly on the field observations of the author and his associates, and on analysis of published data:
Delhi System
(1100± to ?750m.y.)

Aravalli System = BGCI
(I590± to 1000± m.y.)
BGC II = BGC (Serera) = ? Berach Granite
An attempt has also been made to fit this scheme with the recently proposed classifications of the Precambrians.
Sedimentological Studies of Pakhal Sediments from Pakhal Lake Area, Warangal District, A.P.
Authors: Janardan Rao Y. , Satyanarayana K. 
Published: November 2024

Abstract
Sedimentological studies of the Pakhal sediments in the Pakhallake area have been made with a view to understand the environmental conditions of deposition of these rocks which belong to the Precambrian age. Textural properties like grain size, roundness and sphericity have been determined from thin section studies of clastic rocks like quartzose sandstones and orthoquartzites.
The statistical parameters calculated from the formulae suggested by Folk and Ward and their possible geological significance have been discussed. From the basic C. M. patterns of Passega, it has been found that the clastic sediments were deposited in a beach environment acted upon by tractive currents. The Pakhal sediments in this region had their provenance from the granitic rocks and the quartz-magnetite rocks which lie to the west of the Pakhal basin, and were deposited on the beaches and were shifted to the neritic zone of environment.
Structure of the Type Charnockite Area Near Madras
Authors: Sen S. K. , Ray S. , Dasgupta D. 
Published: November 2024

Abstract
In the type area of the charnockites, south of the city of Madras, foliation attitudes of marker horizons of leptynites and of basic granulite bands trace a map pattern characterized by four-fold hinges. The overall structure of the area is brought out by the swerve of axial planes of these folds from NNE in south-west through E-W in the central part to N-S in southern part in a broad sweep. The folding is noncylindrical; and a probable structural interpretation, as advanced here, envisages a series of tight isoclinal folds on which a folding around a N-S axial plane has been superposed.
Behaviour of Trace Elements During the Differentiation of the Basic Igneous Rocks in Cuddapah Basin
Authors: Krishna Rao M. 
Published: November 2024

Abstract
The behaviour of V, Cr, Ga, Sc, Y, Co, Ni, Cu, Ba and Sr, from the basic igneous rocks and their important constituent minerals viz. pyroxenes and plagioclases, of the Cuddapah basin has been discussed with respect to the prevailing physico-chemical conditions, relative mobility, their relation with the corresponding major elements and their choice for appropriate mineral structures. It has been pointed out that in many respects the present behaviour of trace elements is not in keeping with the findings of some of the earlier workers. Even on the basis of the hypothesis of electronegativity as pointed out by Ringwood, the entire implications of the present behaviour of the trace elements cannot be fully and satisfactorily explained. The present data however, to some extent support Goldschmidt's rules of camouflage, capture and admission. In general the trace elements' behaviour in the Cuddapah intrusives is similar to that of other tholeiitic provinces.
Plant Microfossils from the Vindhyans of Son Valley, India
Authors: Salujha S. K. , Rehman K. , Arora C. M. 
Published: November 2024

Abstract
Microplankton, trilete spores and discoidal bodies are recovered from 238 samples of shales, sandstones and limestones belonging to the Semri, Kaimur and Rewa sediments of the Vindhyans exposed along the Son Valley in Uttar Pradesh and Madhya Pradesh. The palyfossils are referred to 16 genera and 25 species out of which 14 species are newly proposed.
Structural Pattern of Rocks Around Dariba, Alwar District, Rajasthan, with Special Reference to Copper Occurrence
Authors: Gangopadhyay P. K. , Chatterjee N. 
Published: November 2024

Abstract
The structural pattern of Delhi system of rocks around Dariba is dominated by open, asymmetrical folds which occur on both major and minor scales. A set of axial plane cleavages, which grades from discrete fractures to slaty cleavage, is consistently developed with the folds. The axial traces of the major fold range in trend from NNE-SSW to WNW-ESE. Although the fold axes vary both in direction and amount of plunge, the axial planes are consistently inclined westwards. The copper ore bodies which have been explored so far, occur in the eastern ridge of Dariba. Mineralisation is practically confined to phyllites ana schists. The lenticular ore bodies have been explored uptil now on the limbs of major overturned synformal fold in the eastern ridge. The axial plane cleavage has been observed to be the main structural plane controlling the distribution of the disseminated sulphides in the rock.
Structure and Petrography of the Quartz-Magnetite and Associated Rocks of Siddipet Area, Medak District, Andhra Pradesh
Authors: Vaidyanadhan R. , Sastry A. V. R. 
Published: November 2024

Abstract
A series of detached hills composed of quartz-magnetite rocks and diabases occur in the districts of Medak, Nizamabad, Adilabad and Karimnagar of Andhra Pradesh. The country rock is granitic gneiss and is cut across by a number of dykes. The structure of these rocks near Siddipet in Medak district has been studied in detail, and a number of traverses also made between Armur and Jagtial to the north in the districts of Nizamabad and Karimnagar to infer the probable overall structure of the region.
The quartz-magnetite rocks contain quartz and magnetite only and are devoid of ferro-magnesian minerals. The diabases in the Siddipet area are divided into two groups, one rich in hornblende and the other in pyroxene on the basis of petrographic study.
From a study of the outcrop pattern of the quartz-magnetite rocks and diabase bands in the Siddipet area, three traces of axial planes of folds (FI, FII, FIII) possibly related to three ages of folding are inferred. These rocks have been faulted along N-S and NE-SW directions. From the overall pattern of outcrop of these rocks in the entire region, it is surmised that the rocks of Siddipet area form a part of a major NW plunging anticline with an overturned western limb and with the nose of the fold being near the Godavari river.
Metamorphism in the Eastern Part of Gangpur Series
Authors: Kanungo D. N. , Mahalik N. K. 
Published: November 2024

Abstract
Metamorphism in the eastern part of Gangpur series and its relation to stratigraphy. structure, tectonics and granitic intrusion has been discussed. Three phases of metamorphic recrystallisation are observed. The early low grade metamorphic phase (M1) belonging to the green schist facies is related to the main movement phase (F1) which deformed the Gangpur series into a major synclinorium. The early phase was followed by the main phase of metamorphism (M2) belonging to the lower amphibolite facies. This phase represents the highest grade of metamorphism for this area. This phase is mainly post-tectonic in relation to the main movement phase (F1). It is believed to be a result of the granitic intrusion into the adjoining area, and has no relation to depth of burial or tectonic level. The progressive metamorphism of the early and main phase was followed by a late phase retrograde metamorphism (Ms) belonging to the greenschist facies.
Stratigraphy and Sedimentation of the Cainozoic Subcrops of Dholka Area, Kaira District, Gujarat
Authors: Ganguly S. 
Published: November 2024

Abstract
Deep drilling by the Oil & Natural Gas Commission in Dholka area of the Cambay basin has revealed that the Deccan Trap which was met in one of the wells at a depth of about 2357 metres, is overlain by an almost complete succession of Cainozoic sediments. The detailed stratigraphical succession has been worked out on the basis of study of subsurface rock samples supplemented by palaeontological and other laboratory data, and electrical, radioactivity, sonic and dipmeter logs recorded in the wells drilled; and attempts have been made to correlate the units with those already established in other parts of the Cambay basin.
On the basis of the lithology, microfaunal and microfloral assemblages, mineral content, clay mineral composition and sedimentary structures observed in these sediments, the sedimentary process involved in their deposition has been envisaged and a tectono-environmental analysis of the Cainozoic sedimentation in this area has been attempted. The predominant lithological association of the Palaeogene sediments, with general paucity of fauna, suggests their deposition in a restricted intracratonic basin with frequent oscillatory movements, resulting in alternations of fresh water, shallow marine and transitional environments in this area. During the Neogene period, which was preceded by a break in deposition during the Late Oligocene, shelf conditions prevailed in the area ranging from mildly unstable littoral conditions in the Miocene to more stable continental conditions in the Post-Miocene epochs.
Fracture Frequency Studies in Western Gangpurs, Orissa
Authors: Ramachandran T. V. 
Published: November 2024

Abstract
In his classic work on 'the geology of the Gangpur State', Krishnan mapped a N-S trending brecciated and silicified quartzite, discontinuously over a strike length of more than 28 km from Tinkura to Rainda along the western contact of the granite gneiss body south-west of Sundargarh. His field studies established this linear quartzite to be a zone of faulting, which, according to him, would have taken place during the waning period of the granitic intrusion accompanying the orogenic movements of the late Dharwar period even as late as the time of post-Gondwana faulting. West of the fault zone, para-metamorphites of the Gangpur group are exposed, within which are seen a number of isolated. linear, lensoid and irregular bodies of granite. The present paper deals with the study of fracture patterns in the southern 7 km portion of the fault zone and the surrounding metasediments, granites and granite gneisses, and their tectonic significance.
Calc-Granulites Around Manalur, South and North Arcot Districts, Tamil Nadu, India
Authors: Saravanan S. , Ramanathan S. 
Published: November 2024

Abstract
The plagioclase - pyroxene - garnet rocks, occurring in the Manalur area, have been designated as 'meta-anorthosite' by Murthy (1959). The authors however, consider them as a member of meta-sedimentary group of Archaeans which have resulted from the metamorphism of calcareous sediments of varying compositions. Since there is a general misconception among some of the Indian petrologists, who consider these metasedimentary calcareous members as 'anorthosites', it is proposed to deal with these rock types, in order to show that they have no association with anorthosites, which are one of the members of the layered complex.
Mineragraphy of Gold-Quartz-Sulphide Reefs of Hutti Gold Mines, Raichur District, Mysore State
Authors: Vasudev V. N. , Naganna C. 
Published: November 2024

Abstract
The gold deposits at Hutti situated on the north western fringe of Hutti-Maski Schist belt are of gold-quartz-sulphide reef type. A detailed study has shown three distinct stages of mineralization. Minerals formed during the first stage are rutile, pyrite (with traces of gold) arsenopyrite, specularite, quartz (reef and vein type) and carbonate. Minerals of the second stage are pyrrhotite. chalcopyrite, sphalerite. galena and gold. Minerals of the third stage are pyrite, calcite and quartz found along numerous minor faults (slips) and major faults. Based on the textural and associational criteria, three generations of gold are distinguished. They are: 1. Gold-pyrite association. 2. Gold-aresenopyrite-quarrz association. 3. Gold-sphalerite-quartz association. The study has further shown that only the gold of the second and third generations constitute the lode. Gold is in the native state and no tellurides are present.
The 'Jaunsar' Problem in the Himalaya - A Critical Analysis and Elucidation
Authors: Srikantia S. V. , Bhargava O. N. 
Published: November 2024

Abstract
A complex association of limestones, quartzites, slates and volcanic rocks and ashes exposed In the Garhwal Himalaya was first called as 'Jaunsar System' by Oldham. Pilgrim and West adopted the name 'Jaunsar' for their Jagas Series c - a selective quartzite-slate association, and Auden variously considered his Mandhali-Chandpur-Nagthat association of diverse lithology, and the Nagth Nagthat Series of quartzite-phyllite association as 'Jaunsar'. Later workers either adopted the classification of Pilgrim and West, or of Auden, or reclassified the Chandpur-Nagthat to include crystallines and metamorphics, without much regard to the larger stratigraphic Implications of the same. This has resulted In great confusion In the stratigraphy of the Himalayas leading to conjectural correlations of formations and hypothetical interpretation of structures.
The present study has shown that the 'Jaunsars' are variously part of the Simla group of Srikantia and Sharma or are part of the sequence of the Mandhali-Chandpur-Nagthat. The recent attempt to include rock types referable to the Jutogh as part of the Chandpur-Nagthat is mainly due to the non-recognition of a thrust contact between these two which is obscured due to post-tectonic metamorphism and deformation, and hence is not an acceptable proposition.
It is now proposed to redefine the term 'Jaunsar' and to strictly restrict it to the restored sequence of Mandhali, Chandpur and Nagthat formations. The Jaunsar group as adopted now represents a typical geosynclinal type of sediments deposited on the eroded surface of the Deoban belt. It is characterised by the association of the Bhowali volcanics and the acid intrusives of the Kharasali gneiss, and is typically eugeosynclinal. Structurally it occurs as a superficial nappe over the isopic zones of the Deoban-Simla group in the southern part of the Deoban belt.
The Jaunsar group, the Simla group and the Rampur formation are considered as contemporaneous formations in the present scheme of correlation of geosynclinal sediments In the Lesser HImalaya.
Evolution of Landforms Over the Nilgiri, South India
Authors: Pardhasaradhi Y. J. , Vaidyanadhan R. 
Published: November 2024

Abstract
Two relict levels of erosion over the Nilgiri are recognised within a polycyclic and polygenetic planar Nilgiri surface. Landform study suggests a pediment cycle for the Ootacamund landforms, the younger of the two relict landforms. The older Dodabetta landforms now stand as vestiges of the original ground at higher elevations. Climate might have been less humid over a major part of this region during the period of pedimentation (post-Miocene) compared to earlier and later times. The Quaternary lowering of temperature in Pleistocene and subsequent warming up of climate are likely to have resulted in the formation of swampy courses, alluvial tracts and peaty subsoils along certain streams over the Nilgiri.
Palaeocurrent Analysis of the Siwaliks of Panjab, Haryana and Himachal Pradesh
Authors: Parkash B. , Goel R. K. , Sinha Pankaj 
Published: November 2024

Abstract
The present paper deals with a study of thickness of cross-bedding units and palaeocurrents as deduced from cross-bedding foreset dip azimuths of the Siwaliks of Panjab, Haryana and Himachal Pradesh. All the three sub-divisions of the Siwaliks-Lower, Middle and Upper exhibit mainly southerly palaeocurrent directions and the variance of cross-bedding foreset dip azimuths seems to decrease from the Lower to Upper Siwaliks. Consistent southerly paleocurrent direction in the Upper Siwaliks suggests that they were probably deposited in a single continuous basin instead of two separate basins.
The Stratigraphy and Structure of the Sittampundi Complex, Tamil Nadu, India
Authors: Ramadurai S. , Sankaran M. , Selvan T. A. , Windley B. F. 
Published: November 2024

Abstract
The Sittampundi Complex has the following igneous stratigraphy from the bottom upwards: gabbro with pyroxenite inclusions, chromite-layered hornblende anorthosite and clinozoisite anorthosite. This stratigraphy is only well preserved in the north-east of the area. The complex has been folded into an isoclinal antiform with the result that the stratigraphy is duplicated in two fold limbs which are locally separated by gneiss. A second phase of open folding has given rise to the present form of the complex as a major interference pattern. Linear mineral fabrics largely formed in association with the first deformation. The complex is a tectonic remnant of a layered igneous body that has been recrystallized and deformed. It is remarkably well preserved in more ductile, quartzo-feIdspathic gneisses that have suffered higher finite strain.
Depositional History of Damuda Sandstone in Lish-Ramthi Valley, Darjeeling District
Authors: Kar P. K. 
Published: November 2024

Abstract
Diagenetic changes and depositional history of the Damuda sandstone of a part of DarjeeJing Himalaya is described. The sandstones are classified as quartzitic and non-quartzitic on the basis of their physical characters. The quartzitic sandstones occur along the entire length of Precambrian Daling metamorphics as a thin zone whereas the non-quartzitic sandstones occupy the major part of the field.
The characters exhibited by the non-quartzitic sandstones indicate diagenetic conditions but in case of quartzitic sandstones it cannot be said with certainty. Possibly dynamic metamorphism caused by Daling thrust has had a role in bringing about the changes.