CONTENTS. General Report of the Geological Survey of India for the year 1937. By A. M. Heron, D.Sc., F.G.S., F.R.G.S., F.R.S.E., F.R.A.S.B., The Hindu Kush Earthquake of the 14th November 1937. By A. L. Coulson, D.Sc., D.I.C., F.G.S., F.N.I., Superintending Geologist, Provisional Statistics of some of the more important Indian Minerals for 1937. By A. M. Heron, D.Sc., F.G.S., F.R.G.S., F.R.S.E., The Geology of Gujarat and Southern Rajputana. By B. C. Gupta and P. N. Mukerjee, B.Sc. (Cal.), M.Sc. (Lond.), D.I.C., Assistant Geologists, Geological Survey of India. (With Plates 1 to 5) Tin-Tungsten Mineralisation at Mawchi, Karenni States, Burma. By J. A. Dunn, D.Sc. (Melb.), D.I.C. (London), F.N.I., F.G.S., Petro- Tin-Tungsten Mineralisation at Hermyingyi, Tavoy District, Burma. By J. A. Dunn, D.Sc. (Melb.), D.I.C. (London), F.N.I., F.G.S., Petrologist, Geological Survey of India. (With Plates 13 and 14) 238-246 Two Fossil Dicotyledonous Woods from the Garo Hills, Assam. By Tirodite, a manganese amphibole from Tirodi, Central Provinces Quarterly Statistics of Production of Coal, Gold and Petroleum in India including Burma: January to March 1938 Bismuthinite and bismutosphærite from Manbhum. (With Plate 19) N147742 The Mineral Production of India and Burma during 1937. By A. М. Heron, D.Sc., F.G.S., F.R.G.S., F.R.S.E., F.R.A.S.B., F.N.I., The Western Margin of the Eastern Ghats in Southern Jeypore. By H. Crookshank, B.A., B.A.I. (Dub.), Superintending Geologist, Are the Equidæ reliable for the Correlation of the Siwaliks with the Cœnozoic Stages of North America? By Guy E. Pilgrim, D.Sc., F.G.S., with an Appendix by A. T. Hopwood, D.Sc., F.L.S. A Seismological Study of the Baluchistan (Quetta) Earthquake of May 31, 1935. By K. R. Ramanathan, M.A., D.Sc. and S. M. Mukherji, M.Sc., Colaba Observatory, Bombay Contributions to the Geology of the Province of Yunnan in Western China. (10) The Distribution, Age and Relationships of the Red Beds. By J. Coggin Brown, O.B.E., D.Sc., M.I.M.M. Earthquake Shocks at Paliyad in Kathiawar. By H. Crookshank, B.A., B.A.I., D.Sc. (Dub.), Superintending Geologist, Geological Survey 596-597 LIST OF PLATES, VOLUME 73. PLATE 1.-FIG. 1.-Aravalli schist country, south-west of Kundanpur, Jhabua State. State. FIG. 2.-View of Aravalli quartzite country, N.E. of Virpur, Balasinor PLATE 2.-FIG. 1. Deccan trap country, Samoi, Jhabua. FIG. 2. General view of Aravalli quartzite ridges, Umria, Bariya PLATE 3.-FIG. 1.--Aravalli quartzite (dip-slope), Hadaph river-section, Umria, Bariya State. FIG. 2.-Low-dipping Aravalli slaty and quartzitic bands, south of Mekhar, Godhra. PLATE 4.--FIG. 1. -Much jointed Aravalli quartzite, Edalwara, Bariya State. FIG. 2.-Weathering of granite, Kothamba, Lunavada State. PLATE 5.-Geological map of Gujarat and Southern Rajputana. PLATE 6.-FIG. 1. -Cassiterite (C) interstitial to wolfram (W). Quartz (Q). × 54. FIG. 2.-Cassiteritic (C) and molybdenite (M) interstitial to wolfram quartz (Q). P. S. 243. × 54. FIG. 4. Schcelite (dark grey), replacing wolfram (light grey). P. S. PLATE 7.-FIG. 1.-Wolfram (W) crystal replaced by scheelite (S). Cassiterite (C) and quartz (Q). Bakelite (B). P. S. 251. × 28. FIG. 2.-Quartz (Q) replacing wolfram (W). A little pyrite (P). FIG. 3.-Pyrite (white) veinlets in quartz (Q) and wolfram (W). P. S. 232 × 54. FIG. 4.-Pyrite (P) veining tourmaline (T), and both replaced and veined by chlorite (C). P. S. 239 B. × 54. PLATE 8.-FIG. 1.-Pyrite (P) and chalcopyrite (C), veining arsenopyrite (A). Quartz (Q). P. S. 164. × 28. FIG. 2.-Arsenopyrite (white) veined by chalcopyrite (grey) and FIG. 3.-Arsenopyrite needles in chlorite (dark grey); the latter replaces quartz (lighter grey) and galena (white). Pyrite (P). P. S. 236. × 54. carbonate (black). P. S. 164. × 180. FIG. 4.--Sphalerite (S) veining and replacing arsenopyrite (A). Also chalcopyrite (C) and carbonate (Ca). P. S. 242. × 84. PLATE 9.-FIG. 1.-Quartz veins in sphalerite. P. S. 173. × 40. FIG. 2.-Starnite (S) and galena (G) which veined stannite but is altered in part to cerussite (Ce). Wolfram (W). P. S. 166. Oil immersion. × 420. FIG. 3.--Molybdenite flake (M) in bismuthinite (B) and quartz (Q), the bismuthinite replacing the quartz along the molybdenite. Note the strong difference in reflectivity between adjacent areas of bismuthinite. P. S. 175. × 54. FIG. 4.-Intergrowth of bismuthinite in galena. Crossed nicols. P. S. PLATE 10.-FIG. 1.-Galena vein (white) in cassiterite (C). Quartz (Q). P. S. FIG. 2. Chalcopyrite (C) partly altered to chalcocite and covellite, and stannite (S) vein along cleavage in galena. P. S. 166. × 235. 235. × 54. 235. × 180. FIG. 3.-Zoning in cassiterite (thin section). Mic. slide 24690. × 24. FIG. 4.--Tourmaline (T) replaced by muscovite (M) and chlorite (Ch) in cassiterite (C) and wolfram (W). Mic. slide 24681. PLATE 11.-FIG. 1.-Cassiterite replaced by interstitial felspar. × 24. X 24. × 24. Mic. slide 24680. FIG. 2.-Cassiterite replaced and veined by beryl. Mic. slide 24687. FIG. 4.-Scheelite replacing platy carbonate. Mic. slide 24683. × 24. PLATE 12.-FIG. 1.--Mica veins (M) in cassiterite (C). Note how one of them stops at the border of scheelite (S) after wolfram, and its position in the latter occupied by clear scheelite. Tourmaline (T). Mic. slide 24688. × 24. × 24. FIG. 2. Tourmaline (T) and cassiterite (C) veined by lepidolite (M). × 24. × 24. PLATE 13.-FIG. 1.-Wolfram veining muscovite (M) which appears also to be interstitial to coarser wolfram (W). Quartz (Q). P. S. 268. × 54. FIG. 2.-Wolfram (light grey) brecciated and veined by quartz × 54. (dark grey). P. S. 268. FIG. 3.-Cassiterite (dark grey) replaced by wolfram (grey). Quartz FIG. 4. Cassiterite (white) veined and replaced by quartz (grey). PLATE 14.-FIG. 1.-Fluorite (F) replacing quartz (Q). Wolfram (W) and tungstite (T). Cracks in fluorite, infilled with bakelite, appear like quartz. P. S. 267. × 54. |