fullerenes in kadapa district

FULLERENES IN MID PROTEROZOIC CUDDAPAH BASIN, INDIA

Synopsis

Background:

The ~2.0 Ga intra-cratonic  crescent shaped Cuddapah Basin is located in the eastern part of the Dharwar Craton and occupies an important place in Indian Geology.  It extends over a length of 440 km and trends in NNE-SSW in the north and NNW-SSE in the south through N-S in the middle.  It has a maximum width of 145 km in the middle and occupies nearly 44,550 sq.km.  The Basin hosts rich deposits of barytes, (vein and bedded), limestone, dolomite, asbestos, basemetals, clay, slates, uranium etc., Diamondiferous, kimberlites, conglomerates, gravels are known from the Basin. Recently methane gas shows are also reported. The recent discovery of the presence of “fullerenes” in a few black tuff samples from  the Mangampeta area of the Cuddapah Basin, analysed  at the Stanford University (Sreedhar Murty 2005) added a new dimension to the mineral wealth, of the Cuddapah Basin and called for immediate attention.

What are Fullerenes?

Fullerene is a pure carbon molecule composed of at least 60 atoms of carbon and exhibits a bucky ball structure as shown in Fig.1. The discovery of C₆₀, C₇₀, the carbon cage molecules popularly known as fullerenes, named after the famous Architect, Buckminister Fullerene  (Kroto et al 1985), opened new and vast vistas in understanding these curious molecules. The fullerenes, like artificial diamonds, can be synthesized from carbon.

Fullerene Applications:

Fullerenes, their derivatives and carbon nano tubes have a number of interesting properties due to their unusual structures and sizes. The size of the individual fullerene molecules makes them ideal building blocks for use in designing molecular units that find  application in nanotechnology. The fullerene family of carbon molecules possesses a range of unique properties. A fullerene nano-tube has tensile strength, about 20 times that of high-strength steel alloys, and a density half that of aluminum. Carbon nano-tubes demonstrate superconductive properties, for commercial applications, including computer memory, electronic wires. Fullerenes can be used in the construction of aerospace vehicles because of the substantial performance gains.  Its molecular nano-technology improves the existing launch vehicle designs. They are very cost-effective compared to the present materials being used. Several fullerene derivatives have interesting pharmacological properties such as anti-Alzheimer’s activity. The fullerene family of carbon molecules thus belonging to a unique class of strategic minerals, hold a great promise in a wide spectrum of fields including future micro-electromechanical systems (MEMS), nanotechnology, solar energy technologies, superconductivity, computer memory, aerospace vehicle technology, designing and building of atomically precise programmable machine assemblies that could conceivably adjust to any environmental conditions.

Natural Fullerenes:

Synthesis of fullerene from carbon in the laboratories is complex and  expensive, while the reported  occurrences of fullerene in nature are rather scanty. The natural fullerenes when they were detected first during early eighties were originally thought to be brought from space since these were found to be constituting an important carrier phase for noble gases in carbonaceous chondrite meteorites. Though the natural fullerenes were thought to be mainly of extra-terrestrial origin, subsequent studies showed their existence in the terrestrial rocks as well. Its first reported occurrence in natural terrestrial rocks was in “shungite”, a ~2.0 Ga. old Proterozoic Formation from Karelia, Russia, containing highly carbonified carbonaceous matter (Buseck et al 1992). This  paved the way for subsequent studies on natural fullerenes (Buseck 2002,  Jan Jehlicka et al., 2003, etc.).  Fullerenes were reported particularly from those lithologies that experienced high energy events such as lightning (Daly et al 1993), wild fires associated with K-T boundary (Heyman et al 1994 a, b, 1995, 1996, 1998) or meteoritic impacts (Becker et al 1994). Occurrence of fullerenes was also reported from the litho-units corresponding to mass extinction boundaries of the Cretaceous-Triassic boundary event (250m.y) as also from the well-established Cretaceous-Tertiary boundary (65 m.y) corresponding to the “Dinosaur” extinction period. Similarly, fullerenes were also reported from Triassic-Jurassic (T-J) boundary, volcano-sedimentary sequences, in carbonaceous chondrite meteorites and breccia samples from the meteorite impact craters, in fulgurite in coal samples, and impact craters of NASA’s Long Duration Exposure Facility (LDEF) space-craft. In India too, occurrence of fullerene is reported from the Cretaceous rocks at the K-T boundary in Rajasthan and in black tuff samples of the Pullampet Formation Proterozoic Cuddapah Basin.

Occurrence of Fullerenes in Cuddapah Basin:

Five black tuff samples from  the Mangampeta area of the Cuddapah Basin, analysed  at the Stanford University (Sreedhar Murty 2005)  indicated  presence of C_60, C₇₀ and C₈₄, suggesting the presence of naturally occurring fullerenes in this part of the world. Fig.2 shows the location map of fullerene occurrence in the Mangampeta, Cuddapah district, Andhra Pradesh.

Encouraged by such convincing results and realizing the vast application potential of this very important and strategic mineral, the Andhra Pradesh Mineral Development Corporation (APMDC), Government of Andhra Pradesh, has come forward to support further studies in this area under a research project and entrusted the responsibility of executing the same to M/s. Geo Resources and Technologies Private Limited (GRTC). 

The main objectives of the project are to ascertain the extent of fullerene occurrence, its nature and distribution, the associated geological and physicochemical conditions, the subsurface model of the investigated area and  to visualize a model for the genesis.