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34 W. T. GORDON. CHAPTER VII. THE COUNTRY BETWEEN BURNTISLAND AND KIRKCALDY. By W. T. GORDON, M.A., B.A., D.Se. The stretch of Carboniferous rocks occupying the southern half of Fife is by far the most interesting and important group in the county; and an excellent opportunity for detailed examina­ tion of the diverse types of rock included in the series is afforded by the almost unbroken line of exposures on the northern shore of the Firth of Forth. In the area around Kirkcaldy the main structures in the series are clearly shown, the folds being continuations of the Midlothian syncline and Pentland anticline of the Edinburgh district. In the heart of the former flexure beds of Coal Measure age occur, and several important seams of coal are exten­ sively worked throughout the area. West of Kirkcaldy the Pentland anticline brings up the lowest strata in the district; but, while in Midlothian rocks of Old Red Sandstone and Silurian age are exposed in its core, the oldest rocks arched up by it in Fife belong to the Lower Carboniferous Ser-ies. The crest of this fold strikes the Fife coast at Burntisland, and passing in a north-easterly direction gradually flattens out, and finally becomes lost about twelve miles inland. Between Burntisland and Kirkcaldy only Lower Carbon­ iferous rocks are exposed, but probably no finer section of these strata exists in Britain than that laid bare along the sea-shore between these towns. In the western limb of the flexure these beds are repeated, but the succession is not so clearly shown, and differs markedly from that in the eastern limb. West of Burntisland sediments greatly predominate, whereas to the east of that town a great thickness of volcanic rocks is intercalated in the series. In the Lower Carboniferous rocks in this area several beds of limestone occur, and one of these-the Burdiehouse Limestone-has been worked in a continuous series of quarries and mines around Burntisland. The anticlinal structure of the district is indicated by this bed, but it is, perhaps, more clearly shown by a higher limestone, namely, the Hurlet seam, which marks the upper limit of the Calciferous Sandstone Series, as the lower group of the Scottish Lower Carboniferous rocks is called. The Hurlet Limestone has been excavated in numerous quarries, now mostly disused, from Kirkcaldy round the Raith Hills PRI.)C. GEOL. Assoc., VOL. XXV. PLATE 2. A.-AGGLOMERATE CUT BY BASALTIC INTIWSION. THE (See page 40') [T'h ato It)· [ a m r s 1I'1igltt , ;1"'., B.-SECTION ON SHORE NEAR KINGHORN. (See page 40.) To face page .,4. THE COUNTRY BETWEEN BURNTISLAND AND KIRKCALDY. 35 nearly to Inverkeithing. The rocks in the core of the fold at Burntisland consist of sandstones, shales, and limestones, lying below the position of the Pumpherston Oil Shale of the Lothians. These beds are invaded by three thick dolerite sills, one of which is exposed near the docks at Burntisland, and another in a road­ cutting north of the town. A few hundred yards farther north a thick bed of sandstone dipping to the north-west is worked at Grange Quarry, and the Burdiehouse Limestone, lying r a ft. below the sandstone, was formerly exposed. Both sandstone and limestone in this western limb of the anticline have been traced eastwards until they were truncated abruptly by the volcanic neck now represented by the Binn. About 500 yards to the north-east of Grange Quarry, however, a limestone is exposed on the northern flank of the Binn, and it may possibly be the Burdiehouse band; if not, it is one of the beds occurring near that position. East of the volcanic neck the section is clearer, and the lime­ stone formerly mined at Brosyhall and Dodhead Quarries is undoubtedly a continuation of the Burdiehouse bed in the eastern limb of the anticline. In the latter quarry a dolerite sill has been intruded into the carbonaceous shales overlying the limestone, and has been converted into" white trap" by the reducing action of the carbon in the shales. Numerous fossil remains have been obtained from Dodhead Quarry, and all indicate that the beds were laid down under lacustrine or estuarine conditions. These remains consist chiefly of land plants, such as Lepidodendron, Lepidophloios, with their fructifications (Lepidostrobus) and fern-like plants (Telangium). A limited fauna is preserved in the limestones, and it includes ostracods and several types of fish (Elonichthys, Eurynotus, Rltizodus, Megalichthys, etc.). The dip of the beds is now towards the north-east, and 150 ft. above the limestone a seam of oil-shale was mined by the now defunct Burntisland Oil Company. The oil-shale has been correlated with the Dunnet seam of the Lothians. A coal seam - the Houston Coal- with its accompanying shales comes on above the Dunnet seam, and completes a series fairly comparable with that represented in the Lothian Oil Shale Group. Shortly after the deposition of the coal, however, a period of volcanic activity supervened, and a great series of la vas and tuffs was poured over the accumulated sediments. The vent from which this series was ejected is now represented by the Binn, This hill lies on the anticlinal axis previously referred to, and is built up of agglomerate cut by numerous dykes, one of which shows columnar structure (PI. 2.A). The neck is irregular in outline, and may really represent two orifices which have coalesced. The larger part is circular in outline, and about 1,500 ft. in diameter. W. T. GORDON. The smaller is about the same dimension in one direction, but only 700 ft. in the other. The material of the agglomerate consists chiefly of volcanic ejectamenta, but numerous pieces of limestone also occur. The latter do not show any signs of alteration, and many contain their original fossil remains quite unchanged. That the Binn formed the chief focus of volcanic activity in the district cannot be doubted, and the thick series of lavas and tuffs which build up King Alexander's Craig may quite well have been erupted from this centre. (It is interesting to note that in the Bathgate and Linlithgow hills, visited by the Association in 1912, a similar volcanic episode occurs on practically the same horizon.) Leaving the Binn, and returning to the section of the lavas exposed on the sides of King Alexander's Craig, a succession of basalts and ash-beds, with intercalations of shales, may be clearly made out. Near the eastern end of the Craig a small neck, truncating the basalts of the Craig, is visible; and some of the tuffs overlying these basalts may have been ejected from that centre. Beyond this point the lavas and tuffs of King Alexander's Craig are continued by a small synclinal fold, but at Pettycur higher beds are again seen dipping towards the east. At that locality beds of sedimentary origin occur between the lava flows, and a rich flora appears to have inhabited the slopes of the ancient volcanoes in the district, for abundant remains of plant life have been obtained from the ash-beds and shales at Pettycur House, both as petrifactions and impressions. while blocks of limestone containing petrified plants have been distributed through the lavas and tuffs. The importance of this flora is considerable, both from a geological and a botanical standpoint. The completeness of the petrifaction allows the botanist to study the internal anatomy of the plants. As a result it is found that the flora as a whole exhibits features which indicate that it was less specialised than that occurring in Coal Measure times. The petrifying material is usually calcareous, with a slight admixture of silica and iron pyrites. In most cases the silica does not exceed 20 to 30 per cent., but in a few specimens the petrifying medium is siliceous. It would appear, from the occurrence of thin lenticular bands of chemically-formed limestone, and pieces of calc-tufa in this region, that thermal springs were present over the area, and probably during periods of volcanic inactivity a rich flora inhabited the region. The springs, no doubt, emitted water highly charged with mineral matter in solution, and plant debris falling into the pools round the springs became waterlogged, sank, and in course of time were petrified. The list of plants from Pettycur is now considerable, and up to the present is as follows: THE COUNTRY BETWEEN BURNTlSLAND AND KIRKCALDY. 37 Protocalamites petIJlcurensis, Lepidocarpon wildianum, Scott. Scott. Stigmaria jicoides, Brongt. Sphenophyllu11l insigne, Botryopteris antiqua, Kidston. Williamson. Dineuron ellipticum, Kidston. Cheirostrobus pettycurensis, Diplolabis rameri (Solms). Scott. Metac!epsytfropsis duplex Lepidodendron pettycurense, (Williamson). Kidston. Stauropteris burntislandira, Lepidodendron veltheimianum, P. Bertrand. Sternbg. Bensonitesfusiformis, R. Scott. Lepidodendron brevifolium, Fern sporangia. Williamson. Heterangiron grievii, Williamson. Lepidophloios scottii, Gordon. Rhetinangium arberi, Gordon. Lepidostrobus veltheimianus, Sohcerostoma ovale (Williamson). Sternbg. Physostoma, sp. Lepzdostrobus mezocarpon, A myeion, sp. Benson. (Lepzdostrobus cylindricus, Gordon in MS.). With occasional intercalations of sedimentary beds the lavas and tuffs continue up to the Hurlet Limestone, which ushers in the marine conditions so characteristic of the Scottish Carboni­ ferous Limestone Series. The total thickness of the volcanic series and associated sediments is about 1,500 ft., and each individual bed may be studied in the section exposed on the sea­ shore. At one or two points features of special geological interest are shown in this volcanic succession. During periods of sedimenta­ tion eruptions of ashes and large bombs have taken place from the neighbouring crater. These have fallen among the soft, sandy and muddy deposits, and the layers of these latter are con­ siderably disturbed in consequence. The succeeding muddy layers, however, pass over the blocks without suffering any distortion of their bedding planes.

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