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Purana basins in India are Proterozoic in age, filled with mostly marine, deltaic, and fluvial sediments, with some alluvial fan deposits in the basin margins. The basin fill is largely undeformed and unmetamorphosed, and the basins occur in many shallow (<5 km), large and small depressions in the Archean-Paleoproterozoic cratons in peninsular India. An understanding of the reasons for the opening and closing of these intracratonic basins is elusive, far more so than that of the better-studied Phanerozoic intracratonic basins in the world. On the basis of meager, but robust new data, published in this century on the Purana basins and their host cratons' lithostratigraphy, paleomagnetism, seismic images, geochronology, and paleontology, we propose a scenario of their opening and closing related to the assembly and disassembly of the supercontinents Kenorland, Columbia, and Rodinia. The Marwar and the Bundelkhand cratons occur in the western and northern Indian blocks, respectively. The southern Indian Block consists of the Singhbhum, Bastar, Eastern Dharwar, and Western Dharwar cratons; these had amalgamated by ca. 2.5 Ga, but split and re-amalgamated along the western margin of the Bastar craton ca. 1.6 Ga. These three blocks, and East Antarctica, were assembled ca. 1000 Ma along the Aravalli-Delhi Fold Belt, Central Indian Tectonic Zone, and the Eastern Ghats Mobile Belt, as part of Rodinia. There are three sets of Purana basins. The oldest set (Papaghni-Chitravati; Kaladgi-Badami; Lower Vindhyan; Gwalior-Bijawar-Sonrai) opened diachronously after 2.0 Ga and closed by 1.55 Ga. Others (Chhattisgarh; Indravati; Khariar; Ampani; Albaka; Mallampalli; Kurnool; Bhima; etc.) opened after the 1.6 Ga amalgamation event in the southern Indian block, and closed shortly after the 1000 Ma collision of East Antarctica with India. In the northern Indian block, the upper Vindhyan basin likely opened after 1.4 Ga. Sedimentation lingered in some of these basins for some time after 1000 Ma but ceased at the latest by 900 Ma. The Marwar basin in the western Indian block opened ca. 750 Ma, after the emplacement of the Malani Igneous Suite, and sedimentation ceased by 520 Ma, before the Cambrian Explosion. We propose that the three crustal blocks were largely separate between ca. 2.0 and 1.0 Ga but may have collided with and separated from each other from time to time. Minor fracturing in the cratons, entirely within the crust, caused them to have uneven topography. The resulting depressions were filled with sediments as sea level rose; they sagged under the sediment load and as a result of far-field effects of packing and unpacking of large landmasses (Kenorland, Columbia, and Rodinia). Ensuing dynamic topography and sea level fluctuations gave rise to the opening and closing of the Purana basins and their sediment fills. Copyright 2015 Geological Society of India

Four unconformity-bound sequences can be identified in the Purana successions in southern India, of which the third sequence (Sequence III) has the widest distribution. Sequence III contains deep-water carbonate units with consistent sedimentological characteristics across the subcontinent. The current extent of field relationships and existing ages has not allowed the correlation and chronology of these carbonates to be established conclusively. Palaeomagnetism may help resolve this essential question for the Purana sedimentation. Here, we report new palaeomagnetic results (HIG+/– pole: 21.7° N, 81.1° E, radius of cone of 95% confidence A95 = 15.9°) from Sequence III carbonates in the Kaladgi (Badami Group) and Bhima (Bhima Group) basins. The HIG+/– magnetization, revealed after the removal of secondary magnetizations that include a present-day field and an Ediacaran–Cambrian overprint, is interpreted to be primary based on its dissimilarity to known younger magnetizations, the presence of distinctly different magnetic components in sites and a positive reversal test. Our HIG+/– pole differs from the c. 1.4 Ga pole and various c. 1.1 Ga and younger poles. Instead, it overlaps with the Harohalli dyke pole that was long considered to be c. 823 Ma in age, but has recently been suggested to be much older with an age of c. 1192 Ma. We therefore consider the uppermost carbonate beds of Badami and Bhima groups to have been deposited during late Mesoproterozoic times. A critical evaluation of parameters from which an earlier Neoproterozoic age for these carbonates was established indicates that the available 40Ar/39Ar, Rb–Sr and U–Pb ages in the Kaladgi and Bhima basins could reflect the timing of post-depositional alteration events.

This presentation examines the history of duckweeds in Chinese, Christian, Greek, Hebrew, Hindu, Japanese, Maya, Muslim, and Roman cultures and details the usage of these diminutive freshwater plants from ancient times through the Middle Ages. We find that duckweeds were widely distributed geographically already in antiquity and were integrated in classical cultures in the Americas, Europe, the Near East, and the Far East 2000 years ago. In ancient medicinal sources, duckweeds are encountered in procedures, concoctions, and incantations involving the reduction of high fever. In this regard, we discuss a potential case of ethnobotanical convergence between the Chinese Han and Classical Maya cultures. Duckweeds played a part in several ancient rituals. In one, the unsuitability of its roots to serve as a wick for Sabbath oil lamps. In another reference to its early use as human food during penitence. In a third, a prominent ingredient in a medicinal incantation, and in a fourth, as a crucial element in ritual body purifications. Unexpectedly, it emerged that in several ancient cultures, the floating duckweed plant featured prominently in the vernacular and religious poetry of the day.

The Cuddapah basin in southern India, consisting of the Palnad, Srisailam, Kurnool and Papaghni sub-basins, contains unmetamorphosed and undeformed sediments deposited during a long span of time in the Proterozoic. In the absence of robust age constraints, there is considerable confusion regarding the relative timing of sedimentation in these sub-basins. In this study, U–Pb isotopic dating of zircon and U–Th–Pbtotal dating of monazite and uraninite from the gritty quartzite that supposedly belongs to the formation Banganapalle Quartzite have been used to constrain the beginning of sedimentation in the Palnad sub-basin. Magmatic and detrital zircons recording an age of 2.53 Ga indicate that the sediments were derived from the granitic basement or similar sources and were deposited after 2.53 Ga. Hydrothermally altered zircons both in the basement and the cover provide concordant ages of 2.32 and 2.12 Ga and date two major hydrothermal events. Thus, the gritty quartzite must have been deposited sometime between 2.53 and 2.12 Ga and represents the earliest sediments in the Cuddapah basin. Monazite and uraninite give a wide spectrum of ages between 2.5 Ga and 150 Ma, which indicates several pulses of hydrothermal activity over a considerable time span, both in the basement granite and the overlying quartzite. The new age constraints suggest that the gritty quartzite may be stratigraphically equivalent to the Gulcheru Quartzite that is the oldest unit in the Cuddapah basin, and that a sedimentary/erosional hiatus exists above it.

The ‘Purana’ basins were long considered Neoproterozoic basins until geochronology and palaeomagnestism showed parts of the Chattisgarth and lower Vindhyan basins to be a billion years older. Historically, the successions in the Chattisgarth Basin are correlated with similar successions in the Pranhita–Godavari and Indravati basins. In India, differentiating between early–late Mesoproterozoic rocks and those spanning the Mesoproterozoic–Neoproterozoic boundary is possible by comparing magnetic declination and inclination; palaeomagnetism is therefore a very useful correlation tool. Here we report a new Stenian-aged palaeopole (50.1°N, 67.4°E, radius of cone of 95% confidence A 95 = 12.4°, precision K = 30.1) from carbonate and shale successions of the Pranhita–Godavari and Chattisgarth basins (the C+/– magnetization). In addition, an early diagenetic remagnetization (component A) was identified. No primary or early diagenetic magnetizations were identified from the Indravati Basin. Here, as well as in stratigraphically higher parts of the other two successions, widespread younger magnetic overprints were identified (B+ and B– magnetic components). Our C+/– palaeopole is constrained by palaeomagnetic stability field tests, is different from known 1.4 Ga and 1.0 Ga Indian palaeopoles, but similar to a 1.19 Ga palaeopole. Penganga Group (Pranhita–Godavari Basin) deposition was probably initiated at around 1.2 Ga. A similar palaeomagnetic signature confirms its correlation with the Raipur Group (Chattisgarth Basin), of which the deposition spans most of the Stenian period (c. 1.2–1.0 Ga). Sedimentation in these groups began significantly later than c. 1.4 and c. 1.6 Ga, as suggested by ages reported from below the Raipur and Penganga groups, respectively.

Felsic tuff beds with some presumed sedimentary components were reported from the Owk Shale (Kurnool Group; bearing Neoproterozoic fossils) in the upper part of the sedimentary succession in the Cuddapah basin in India by Saha and Tripathy (2012a). Our optical and SEM petrographic study of three thin sections, however, indicates that the parent samples are sandy mudstones with variable amounts of a felsic volcaniclastic component. New highquality U-Pb (SHRIMP and LA-MC-ICPMS) ages of 133 detrital zircon grains from a sample show that one grain is ca. 1880 Ma, one grain is ca. 3300 Ma, and the ages of the remaining 131 grains fall between 2690 Ma and 2429 Ma, the population averaging 2522 ± 36 Ma. The data indicate that the zircons are detrital grains derived from the ca. 2.5 Ga granitic/gneissic/greenstone basement of the Dharwar cratons that also host minor older Archean enclaves. The single 1880 Ma grain could have come from a ca. 1.9 Ga LIP. In the absence of any younger magmatic zircon, the absolute age of the Owk Shale remains elusive. Copyright 2013 Geological Society of India

What rules of fighting (armed combat) does Hinduism espouse? The sacred texts are the pre-eminent sources, so these need to be summarized and compared to each other. Teaching mostly through stories, the texts describe deeds of people (especially warriors), gods and demons to show how to behave and not to behave in war. While the injunctions in the Mahābhārata and Arthaśāstra are already covered in the literature, including in this journal, this present work examines the Purāṇas in depth. After a thorough search of all relevant passages, we find the Purāṇas to be very similar to the epics in terms of the list of prescribed and proscribed actions in war that they provide. We also make comparisons to international humanitarian law (IHL); as in the epics, we find that the Purāṇas contain many similar provisions to those found in IHL but that they go above and beyond what is required by IHL in urging that fighting be fair at the tactical level (i.e., between individual fighters). Being religious texts, the Purāṇas also deal with the afterlife consequences of both righteous and unrighteous combat.