An approach to an integrated micro-watershed management plan of outer Himalayan range of Himachal Pradesh, India

Due to the ever-increasing demand on water resource, the pressure on its judicious utilization is also increasing. Besides being precious, this resource is also complex to manage on account of its dynamic behaviour. In India emphasis is being placed on making the local-level users participate in the management of natural resources at the watershed level. Therefore, it is imperative that local-level organizations be strengthened by providing the integrated watershed management tools which are user-friendly, but still use all the scientific knowledge to arrive at the appropriate decisions. This paper demonstrates the use of GIS-based overlay method for local-level planning, incorporating the sustainability aspects of watershed development. A case study has been taken in the Lower Bhangal Micro-watershed of the outer Himalayan range to demonstrate the approach of matrix/ranking and overlay methods to delineate priority areas for watershed management plan.     

Occurrence of Proterozoic black shale-hosted uranium mineralisation in Tal Group,Sirmour district,Himachal Pradesh

Black shale type uranium deposits, though of low grade (<0.001 to 0.05% U₃O₈), contain large uranium resources because of their immense volume. The Neoproterozoic-Cambrian Krol-Tal Himalayan sequence covering a cumulative area of about 1000 sq km in five different synclinal basins from Sirmour district, Himachal Pradesh in the west to Nainital district, Uttar Pradesh in east contain such black shale horizons. The uranium mineralisation found in black shale in the Nigalidhar syncline of Himachal Pradesh and its implication of being an indicator for search of such uranium deposits in Himalayas is discussed.     

Trace fossils from Bhuban Formation,Surma Group (Lower to Middle Miocene) of Mizoram India and their palaeoenvironmental significance

A detailed ichnological study performed on the Bhuban Formation, Surma Group (Lower to Middle Miocene) of Mizoram, India reveals the occurrence of rich and diverse trace fossils. These have been collected from the two localities in Aizawl, i.e., Bawngkawn and Ropaiabawk, where sandstone—shale sequence is well exposed. Total 20 ichnospecies of 14 ichnogenera have been identified which include Arenicolites isp., Cochlichnus anguineus, Helminthopsis abeli, Laevicyclus mongraensis, Ophiomorpha borneensis, Palaeophycus tubularis, Palaeophycus heberti, Palaeophycus sulcatus, Palaeophycus alternatus, Pholeus abomasoformis, Pholeus bifurcatus, Planolites beverleyensis, Planolites annularis, Polykladichnus irregularis, Rhizocorallium isp., Skolithos linearis, Taenidium satanassi, Teichichnus rectus, Thalassinoides horizontalis and Thalassinoides paradoxicus. Ethologically these ichnogenera display dwelling and feeding activities of the infaunal organisms. Arenicolites, Ophiomorpha, Polykladichnus and Skolithos are the members of the Skolithos ichnofacies while Palaeophycus, Planolites, Rhizocorallium and Thalassinoides are the members of the Cruziana ichnofacies. The presence of Skolithos ichnofacies indicates sandy shifting substrate and high energy conditions in foreshore zone while the Cruziana ichnofacies indicate unconsolidated, poorly sorted soft substrate and low energy condition in the shoreface/offshore zone. These ichnogenera indicate foreshore to shoreface-offshore zone of shallow marine environment for the deposition of the rocks of the Bhuban Formation of Mizoram.     

Rapid visual screening of different housing typologies in Himachal Pradesh,India

Natural Hazards - Methods capable of assessing the vulnerability of houses for future earthquakes are of fundamental importance for the safety and development of an area. As the detailed assessment...     

Trace fossils from the late cretaceous Lameta Formation,Jabalpur area,Madhya Pradesh: Paleoenvironmental implications

In Jabalpur area about 18 m to 45 m thick Lameta Formation is stratigraphically divisible into five lithounits namely, Green Sandstone, Lower Limestone, Mottled Nodular Beds, Upper Limestone and Upper Sandstone. Having differentiated lithofacies constitution and here grouped as facies associations, these units are intensively burrowed and sparingly fossiliferous. Ichnogenera including Arenicolites, Calycraterion, Fucusopsis, Laevicyclus, Macanopsis, Ophiomorpha, Paleomeandron, Rhizocorallium, Stipsellus, Thalassinoides and Zoophycos are recovered from the Lower Limestone, Mottled Nodular Beds and Upper Limestone associations of the Lameta Formation of Jabalpur area.Among these, Arenicolites, Calycraterion, Laevicyclus, Ophiomorpha, Rhizocorallium, Stipsellus and Thalassinoides belong to mixed Skolithos and Cruziana ichnofacies and indicate sandy backshore to sublittoral condition of deposition. Additionally rhyzocretes, some times chertified, are also present in different parts of the Lameta Formation. Ichnofacies assemblage supported by sedimentological information suggests that the Lameta Formation of Jabalpur area was deposited in coastal marine settings where sediments were subaerially exposed intermittently.     

内蒙古中新世槭属植物化石的首次发现

正内蒙古第三纪地层的沉积类型属于陆相沉积,它广泛分布于全区各地,其中汉诺坝组中赋存数量丰富、种类繁多的植物大化石及孢子花粉,是古生物学者研究内蒙古新生代化石的重点地层。汉诺坝组岩层近水平,多构成开阔平坦的高台地形,主要由一套灰、黑、紫灰色橄榄玄武岩组成,夹砖红色泥岩、灰白色泥灰岩及灰黑色泥岩和黑色油页岩。     

Before the flood: Miocene otoliths from eastern Amazon Pirabas Formation reveal a Caribbean-type fish fauna

The Pirabas Formation of Early Miocene age represents the final stage of the central western Atlantic carbonate platform in northeastern South America, predating the emplacement of the Amazon delta system. The otolith-based fossil fish fauna is represented by 38 species typical of a shallow marine environment. A total of 18 species are described new to science from the families Congridae, Batrachoididae, Bythitidae, Sciaenidae and Paralichthyidae. The fish fauna was associated with high benthic and planktic primary productivity including seagrass meadows, calcareous algae and suspension-feeders. The break of todays shallow marine bioprovince at the Amazonas delta mouth is not evident from the fish fauna of the Pirabas Fm., which shows good correlation with the Gatunian/proto-Caribbean bioprovince known from an only slightly younger time window in Trinidad and Venezuela. Differences observed to those Early Miocene faunal associations are interpreted to be mainly due to stratigraphic and geographic and not environmental differences. We postulate that the emergence of the Amazonas river mouth close to its present day location has terminated the carbonate cycle of the Pirabas Fm. and pushed back northwards a certain proportion of the fish fauna here described.     

Glacial meltwater impounding: Evidence from the late Quaternary glaciogenic sediments in the Sangla valley, district Kinnaur, Himachal Pradesh, India

Sangla valley is situated at an altitude of ~ 3500 m above mean sea level and lies in the Kinnaur district of Himachal Pradesh. It is fed by river Baspa, a tributary of river Sutlej, that entrenches through the Quaternary glaciogenic deposits before emerging out of the valley and joining the river Sutlej at Karcham. The unstratified to stratified glaciogenic deposits consist of large boulders to fine silt and are classified into four major depositional facies on the basis of sedimentary texture and depositional environment. The facies — basal conglomerates, debris flow, water/sheet flow and laminites — represents the change in the environment of deposition from glaciofluvial to lacustrine and also the extent of the glacier to the valley floor during late Quaternary.     

Forced regressive shoreface sandstone from Himalayan foreland: Implications to early Himalayan tectonic evolution

Sedimentology and sequence stratigraphic analysis of the ∼ 31 Ma old marker White sandstone unit from the Subathu Sub-basin, NW Himalayan foreland, suggest it to be a forced regressive wedge (FRW) formed during the transition from the marine Subathu Formation to the continental Dagshai Formation. The FRW is bounded between the “Surf diastem” below and type 1 unconformity at the top and differs from RSME (regressive surface of marine erosion, occurring below) bounded FRWs described from other classical coastal/foreland settings. Correct identification of bounding surfaces of a FRW has an important implication to the estimation of rate of relative sea-level (RSL) fall. A faster rate of RSL fall, higher than the sedimentation rate, has been postulated for the erosion of the lower shoreface and RSME. Using the logged thickness of the Subathu/Dagshai transition zone including the White sandstone (bounded between the “Surf diastem” and unconformity), available chronology and eustatic sea-level fall (0.023 mm/year at 31 Ma), a higher RSL fall than the sedimentation rate (0.07 mm/year) has been inferred during the deposition of the White sandstone. Petrography of sandstones and their Sr and Nd isotopic compositions indicate a major provenance switch-over from dominant mafic/ultramafic to metamorphic source from White sandstone (∼ 31 Ma) onwards attesting the link between hinterland tectonics, provenance and forced regression. The provenance switch-over at 31 Ma was earlier inferred to be driven by proto-Himalayan thrust propagation in the foreland. Using a simple isostatic model, on the contrary, a mechanism of accelerated surface uplift (at a rate of > 0.10-0.15 mm/year) is suggested for both provenance change and forced regression.     

Temporal change of glaciers area and geomorphometric parameters in Parbati valley,Himachal Pradesh,India

Temporal change in the glacier coverage is analyzed for the period between 1962 and 2003 in Parbati valley, Himachal Pradesh. It is observed that the total glacier cover has been decreased by 17% ranging between 8 and 100% for individual glacier. The pattern of de-glaciation shows a high degree of shrinkage in outer zone of Parbati valley, while least shrinkage is observed in the inner valley. The present study is conducted to establish relationship between glacio-geomorphic parameters and glaciers shrinkage pattern to predict the future glacier cover in warming scenario. A systematic change is observed for glacio-geomorphic parameters associated with temporal change in glacier cover. It is observed that mean and minimum elevation, slope, relief and duration of insolation have changed substantially. Maximum elevation, plan/profile curvatures and aspect have shown less change from 1962 to 2003. A correlation matrix between glacio-geomorphic parameters for glaciers between 1962 and 2003 shows that the recent glaciers are much more controlled by terrain characteristics than that in the recent past.     

从下草湾化石群看洪泽湖地区中新世时期的生物多样性

泗洪下草湾被古生物学家称之为中新世生物化石的宝库,对于研究新生代植物、软体动物、脊椎动物乃至灵长目动物的演化与传播都有重要的意义。从其多种类型的化石记录看,在中新世时期,洪泽湖地区显示出丰富的生物多样性,而由河湖相向河流相的转变以及地质活动的加剧,亦引起了该地区生物多样性的显著变化。     

Additional coralline algae from the Lower Miocene to Late Holocene sediments of the Porbandar Group,Gujarat

The Neogene-Quaternary sediments well exposed in the Porbandar Basin are characterized by coralline algae. The limestone, calc-arenites and marls are the dominant lithology of this sequence. The present paper documents ten species of coralline algae. Among these, the nongeniculate coralline algae are represented by four species and geniculate coralline algae include six species. The sediments yielding this algal flora range in age from the Lower Miocene to Late Holocene.     

Miocene shallow-water limestones from São Nicolau (Cabo Verde): Caribbean-type benthic fauna and time constraints for volcanism

Shallow-water limestones of presumed Late Cretaceous and Eocene age, interbedded with basaltic lavas, were described by earlier authors from São Nicolau in the northwestern part of the Cabo Verde archipelago. If confirmed, these ages would imply late Mesozoic shallow-marine and subaerial volcanic activity in the Cabo Verde archipelago, and document a geological history very different from that known so far from other Cabo Verde Islands, from which no subaerial volcanic activity before the mid-Cenozoic is known. Our re-investigation of the foraminiferal fauna indicates a Late Miocene age for the presumed Late Cretaceous and Eocene limestones. The hypothesis of a long-lived hot spot, active by the Early Cretaceous, and of a major island-building stage in the Cabo Verde Islands during this period, is therefore not supported by the present bio- or chronostratigraphic data.     

霍邱县白大山群古生代化石的发现

霍邱县白大山地区的石灰岩样品,经实验室分析后获得了大量海绵骨针（Spicules）、苔藓虫（Bryozoa／Polyzoa）及小壳类化石（Small shelly fossil）,此类化石的发现,为白大山群的地质时代划归古生代提供了重要依据。     

Macro-zonation of landslide susceptibility in Garamaura-Swarghat-Gambhar section of national highway 21, Bilaspur District, Himachal Pradesh (India)

Landslides the most common geo-hazard in hilly terrain are short lived phenomena but cause extraordinary landscape changes and destruction of life and property. The frequency and intensity of landslides occurrences along NH-21 during the rainy season not only disrupts traffic movement but also misbalance the agro-economic and developmental activities of the region frittering away thousand crores of rupees from the exchequer. An assessment of landslide susceptibility is, therefore, a prerequisite for sustainable development of the region. The present study deals with the preparation of macro-zonation maps of landslide susceptibility in an area of about 100 sq km on 1:50,000 scale across Garamaura-Swarghat section of National Highway-21. The map has been prepared by superimposing the terrain evaluation maps in a particular zone such as lithological map, structural map, slope morphometry map, relative relief map, land use and land cover map and hydrological condition map using landslide susceptibility evaluation factor rating scheme and calculating the total estimated susceptibility as per the guidelines of IS: 14496 (Part-2) 1998). Numerical weightages are assigned to the prime causative factors of slope instability such as lithology, structure, slope morphometery, relative relief, land use and groundwater conditions as per the scheme approved by Bureau of Indian Standard for the purpose of landslide susceptibility zonation. The area depicts zones of different instability. The identified susceptibility zones compared with landslide intensity in the area show some congruence with the weightages of the inputs. The incongruence in intensity and frequency of landslide occurrences and the inferred susceptibility zones of BIS scheme allow other geotechnical considerations and causative factors to be incorporated for the landslide susceptibility zonation.     

南秦岭文县地区三河口群微古植物化石的发现及其地质意义

在南秦岭西段文县北部三河口地区,古生代浅变质沉积岩系三河口群分布广泛,前人将其划分为桥头组、屯寨组和洋汤寨组.在其中部的屯寨组中首次发现了微古植物化石,计30多个种属,时代确定为晚震旦世,为三河口群的划分与解体提供了新的依据,证实桥头-康县裂陷盆地是南秦岭新元古代裂陷海槽的组成部分.     

Gastrochaenolites ornatus Kelly and Bromley and other trace fossils on a Middle Miocene omission surface from the Aures Massif,Algeria

Trace fossils provide detailed palaeoenvironmental and palaeoecological information of both ancient and modern sedimentary systems. During middle Miocene times the Aures Massif located in the northeastern part of Algeria, was affected by, at least, one marine transgression. The latter led to the installation of a carbonate platform, which is placed, for the first time, in a Mediterranean context. In the Rhassira basin, the Middle Miocene marine succession is characterised by carbonate platform deposits dominated by rhodolith beds, typical of those known throughout the Mediterranean area. This succession can be divided into many units separated by discontinuities interpreted here as omission surfaces. The Djebel Arhane section shows two omission surfaces characterised by a pre-omission suite (firmground) represented by Balanoglossites burrows for the first surface and Gastrochaenolites ornatus burrows/borings for the second one, and an omission suite (hardground) as evidenced by the bioerosive structures Trypanites and Caulostrepsis, in both surfaces, respectively. Gastrochaenolites ornatus traces were formed and preserved in firm, compact, semi-lithified and fine-grained substrates (firm- to hardground), indicating the Glossifungites ichnofacies. They show bioglyphs which have been formed during contraction of the posterior adductor muscles. These suggest that their tracemakers were represented by suspension-feeding bivalves, most probably Pholadidae or Mytilidae, which rotated during penetration. The fill of these traces is composed of marine deposits related to a transgressive lag. The omission suite is divided into two ichnocoenoses: (i) pre-lithification burrows/borings, and (ii) post-lithification borings. This is the first report of the ichnotaxon G. ornatus from Algeria.