March 3, 1916. THE COLLIERY GUARDIAN 407 The separation into five divisions is justified, not only by the fossils, but also by the petrographic character of the rocks. The lowest zone consists mainly of black schists with a few thick intermediate beds of sand. The coal fields are separated by comparatively wide distances. In No.' 4 zone the sandstones are comparatively frequent; and to this zone belong the large barren measures encountered in several borings. Zone 3 has few sandstones, and the seams are thick and close together. The two upper zones are characterised by the occurrence of very pale clay schists and whitish sand- stones. Here, too, the seams are thicker and closer together. In general, it may be said that the upper series (“ assise superieure ”) is formed of light-coloured rocks, whilst dark rocks predominate in the lower series (“ assise inferieure ”). Table I. r Zone • ■ Zone B< fT. Upper series (“ Assise superieureJ") which is rich in fossil plants and consists of the following zones : 1. Zone with numerous Dictyopterides A 2. Zone without Dictyopteris, but rich in Neuropt er is f tenuifolia ) ["II. Lower series (“ Assise inferieure poor in fossils : 3. Zope with fairly abundant Carbonicola, and beds rich') in plant remains : Neuropteris heterophyIla, Catamites, ? Cordaites, Lonchopteris ) 4. Zone with only occasional plant and animal remains j 5. Zone very poor in plant and (a few) animal remains ( (Carbonicola, Anthracomya) C Pale clay schists, whitish sandstones, numerous seams Few sandstones, thick, closely-set seams Many sandstones; barren measures Light Over 20 coloured per cent strata | of gas. J Dark > coloured strata Black schists, with thin intermediate sandy beds; few seams J Below 20 per cent, of gas. Table II.—Classification and Correlation of the Sections of the Coal Fields of Belgium and Western Germany. Haine-Sambre- Meuse trough. Campine. Lower-RhenBh Westphalia. Inde district. Belgian official and RenieKs 1913 classi- cation. Fourmarier and Renier [1906] and 1913. Schmitz and Stainier 1910. Denoel 1904 (see fig. 5). Generally-admitted classification. Holzapfel 1910. West. Class of coal : East Flenu series (zone with Asolanus camptotaenia) Zone [1] 5: Lin- opteris (Dicty- opteris) very frequent Zone A: Poor in coals, but these rich in gas Stage I.: Seams in groups of 2-3, separated by thick pale schists Several seams over 1 m. thick Total coal 1’6 per cent. Over 35 per cent, of gas. Thickness 500 m. Charleroi series (zone with Lonchopteris JBricei) Zone [2] 4: Lin- opteris (Dicty- , opteris) rare, Neuropteris tenuifolia fre- quent Zone B: Rich gas co .Is Stage II.: Numerous thick, closely-set seams L i alternating with schists of sandstone bi Total coal 3’2 per cent. ; 30 per cent, and more of gas Thickness 280 m. Gas- gaming and gas coal Gas-flaming b and gas coal Gas-flaming coal sec- tion characterised north of the Lippe by pale schists, with Neuropteris tenui- folia 45-37 per cent, of gas Thickness 350-500 m. Zone [3] 3 : Abun- dant animal remains and in- termediate beds with numerous plant remains, especially Neu- ropteris and Lonchopteris Zone C: Upper") : barren measures. I •] I. mar. horizon [ S in the top 100 m. [ Seams alterna- | ting and thin J "| Stage III.: About 15 thick, closely-set seams, separated by black schists Total coal 4’8 per cent. Gas content mostly 20-25 per cent., b more rarely 30 per cent. Typical coking coal horizon Thickness 240 m. Long-flame > bituminous coal. u Gas coal section (Lonchopterides) g With about 37-33 ft per cent, of gas. § Thickness about 75'J m. 2 Gas and > long-flame bituminous I coal. I and (Sonnenschein horizon) Chatelet series (zone with Neuropteris Schlehani or Gas- trioceras carbo- " narium) (Boundry between lean coals and pZone [4] 2: Nunier- £ ous animal and 3 plant remains ft Zone D: Very rich in bituminous coal "II. mar.h Zoi e E : Low^r horizon 4*> mm. below barren < upper bco ! mea- sures edge III. mar. horizon 1’ 1 “Poudingue I 8 houillier ” C Barren measures') Andenne series (zone with Pecopteris aspera or Glyphio- cer is bilingue) Zone [5] 1: Plant remains very rare, and animal remains scanty Stage IV.: Grey schists with frequent sand- stones Seams 40-50 m. apart. 2| per / cent. coal. Thickness 160 m. Greater barren measures 160-200 m. thick Stage V.: A few thin seams Smaller barren measures, 100-160 m. thick Small seams at wide intervals Total coal 1’05 percent; 12—23 per cent, of gas Thickness 380 m. Y Coking coal (• with 18-25 C per cent. ) of gas. 1 ! Coking | coal. J Six lower bituminous coal seams of Stage III. and upper portion of Stage IV. d I Semi-bitumi- b nous and | lean coal. J . o p’ Bituminous coal £ section (Sphenop- teris Laurenti) % With about 33—2u a per cent, of gas o Thickness about 750 m. ft J ’ Sonnenschein seam 02 g Barren measures P below Sonnen- schein lean coal b S’ section (Neurop- il teris Schlehani) | tb with about 20 5 J g Per cent, of gas Barren. Binnenwerke over Schlem- merich seam Binnenwerke under Schlem- mericb seam Breitgang horizon Gedau conglomerate Wilhelmine horizon This classification seems to justify comparison with tliat of the Haine-Sambre-Meuse trough, where the following divisions occur, from hanging wall to floor :— r Upper I West- phalian | L Lower f West- | phalian or | Namurian Flenu series Charleroi series Chatelet series Andenne series Chokier series Zone wutli Asolanus campto- tsenia Zone with Lonchopteris Bricei Zone with Neuropteris Schle- hani or Gartrioceras car- bonarium Zone with Pecopteris aspera or Glyphioceras bilingue Zone with Adiantites oblongi- folius or Glyphioceras diadema The most complete section of the productive carboni- ferous in this trough is found in the “ bassin couchant ’’ of Mons, all the strata being present. Next, in point of completeness, come the basins of the Centre, Liege- Seraing, and Charleroi, although here considerable thick- nesses of the upper strata are lacking. In the other three basins—Basse-Sambre, Andenne-Huy, and Herve —only the strata down to the lowest members of the Charleroi series are present. The Flenu series corresponds to the uppermost zone of Fourmarier and Renier in the Campine; the Charleroi series comprises zones 2, 3, and, in part, 4, of these workers’, the Chatelet series,' approximately the remainder of 4; and the Andenne series corresponds approximately to zone 5, so that the Chokier series would be 'lower than zone 5. On account of the pre- dominating fossil, it is also known as the “ Glyphioceras diadema series.” Of considerable interest in the comparison of the Campine with the Kent basin is the fact that limestones with crinoids also occur in the Haine-Sambre-Meuse trough. In the Campine, the Belgian puddingstone horizon lies approximately between zones 4 and 5; in the Haine- Sambre-Meuse basin it is at the base of the Chatelet series; whilst in Westphalia it forms the boundary between the lean coal division and the barren measures. Above the puddingstone horizon 5, Schmitz and Stainier distinguish between zones differentiated by the occurrence and quality of the contained coals. These zones will be dealt with later, along with the marine horizons. Forir differentiates between an upper zone rich in seams, a barren zone, and one with few’ seams. Denoel’s classification seems to be the one most suit- able for application to the boring tables; and this worker also attempted to parallelise the seams in the various Campine borings, and to separate the horizons carto- graphically. This he did on the basis of the petrographic differences, homogeneous measures of great thickness being separated. He also took into consideration the content of gaseous constituents, the distances separating the seams, the position of the seams, etc., in relation to thick sandstone and clay schist measures, together with the palaeontological classification given by Fourmarier and Renier. As a rule, it is rare that sufficient analogy exists between the strata in two adjacent borings for the parallelisation to be carried out without trouble. It is only by taking into consideration a number of borings distributed over a wide area that anything like a satis- factory conclusion can be obtained. Denoel, also, differentiated five zones, which, how- ever, differ somewhat from those of Fourmarier and Renier, and are better adapted for the classification of the borings. (1) In the northern portion of the Campine a number of borings penetrated the uppermost carboniferous stage (fig. 4), in which the coal seams are grouped in twos or threes, the group being separated by thick barren measures, chiefly pale schists. Some of these seams are over 40 in. thick, but the mean proportion of workable coal is only 1-6 per cent. The gaseous constituents do not fall below 35 per cent. All the borings lie in the first fossiliferous zone of Fourmarier and Renier. The total thickness of the zone is about 500 m. (2) The second stage was revealed by some 20 bore- holes, extending, from the Meuse Valley, throughout the province of Antwerp. It contains a large number of fairly thick and closely set coal seams, alternating with schists and sandstone. The proportion of work- able coal is higher than in zones 1 and 3, the average being 3-2 per cent. There are, in addition, a larger number of thinner seams. All the coals belong to the gas coal series, with 30 per cent, and more of gas. (3) The third stage comprises about 15 thick and very closely set coal seams, separated by black schist. Sand- stones are rarely found. The mean proportion of coal is 4’8 per cent., and the quality is partly coking coal, with 18 to 25 per cent, of gas, and partly richer bitu- minous and gas coal. Palaeontologically, this stage corresponds with the third zone of Fourmarier and Renier. The total thickness is about 240 metres. (4) In the fourth zone the schists are grey, alternating with numerous sandstones. The seams are 40 to 50 metres apart, and consequently the proportion of work- able coal is not more than 2 per cent. The coals must be classed with the bituminous coal§,, but differ con- siderably in gas content. The total thickness is 160 metres. Below this fourth stage lie the important barren measures, 160 to 200 metres thick, forming an admirable stratiigraphical horizon in the southern part of the basin. A large number of boreholes have traversed these measures (Nos. 21, 27 and 29 completely, 18, 16, 28, 25, 56 and 35 partly). It is not improbable that the measures are still 100 metres thick in the borings 22 and 26. (5) The fifth stage lies below these barren measures. In the first place it contains a few thin seams, and then a second barren deposit 100 to 160 metres thick, under which the coal measures become progressively poorer in coal. The seams, which are thin, are far apart, so that only about 1’05 per cent, of workable coal can be reckoned with. The gaseous constituents vary between 12 and 23 per cent. The stage has a thickness of 380 metres. The 4th and 5th stages correspond to the zones 4 and 5 of Fourmarier and Renier; and, according to Denoel, a sixth stage should be added at the base of the productive carboniferous. Though this stage is still unknown, it has probably been tapped in boring 49, where very thin anthracitic seams, with 6 per cent, of gas, were found. Fig. 5 illustrates, on the basis of Denoel’s classifica- tion, the strata traversed by a large number of deep