摘要:

AbstractIn a recent re‐survey of the Bala District the following sets of minor faults have been recognised: two sets of pre‐cleavage, strike‐slip faults which are apparently related to a number of small shear zones and which have no known equivalents in adjoining areas; a complementary system of post‐cleavage, strike‐slip faults which are correlated with similar faults in other parts of North Wales; a set of post‐cleavage, dip‐slip faults probably younger than the complementary ones; and a set of oblique‐slip faults parallel to the main Bala Fault and presumably

ISSN:0072-1050    

DOI:10.1002/gj.3350020102

出版商:John Wiley&Sons Ltd    

年代:1961

数据来源: WILEY

摘要:

AbstractDiagenetic fabrics (textures and structures) have been examined in thin sections of Dinantian limestones mainly from the Avon Gorge, North Wales and Yorkshire. Six processes are shown to have been responsible for the change from unconsolidated sediment to limestone. These are: (1) granular cementation and drusy growth, (2) rim cementation (secondary enlargement), (3) pressure solution, (4) grain growthsensu stricto, (5) mechanical deposition in cavities of post‐depositional age, and (6) post‐depositional formation of cavities by erosion and solution in a carbonate mud.Grain growth, a process well known to metallurgists, acts in monomineralic fabrics of low porosity in the solid state. The intergranular boundaries wander so that some grains enlarge while others shrink and disappear, so bringing about a general increase in coarseness.In all the limestones the mosaic between the mechanically deposited particles (skeletal debris, pellets, ooliths) is one of three types. These are granular cement, rim‐cemented detrital crystals, and a mosaic caused by grain g

ISSN:0072-1050    

DOI:10.1002/gj.3350020103

出版商:John Wiley&Sons Ltd    

年代:1961

数据来源: WILEY

摘要:

AbstractSome sedimentary structures from the Lower Keuper Sandstones, recorded by H. C. Beasley mainly from the area round Liverpool, are redescribed. Two of these, flute casts and groove casts, are well‐known in the marine greywacke facies. Attention is drawn to records of their occurrence in other facies. The origin of these structures is briefly discusse

ISSN:0072-1050    

DOI:10.1002/gj.3350020104

出版商:John Wiley&Sons Ltd    

年代:1961

数据来源: WILEY

摘要:

AbstractThe paper records the little‐known and now extinct marble industry of Ashford‐in‐the‐Water, Derbyshire. An account of the distribution of the dark‐grey limestone used as Black Marble, and the other limestones and materials used for inlaying is included. Methods of mining and processing the Marble and the history of the industry are

ISSN:0072-1050    

DOI:10.1002/gj.3350020105

出版商:John Wiley&Sons Ltd    

年代:1961

数据来源: WILEY

摘要:

AbstractRecent borings have provided considerable additional information in connection with the post‐glacial evolution of south‐west Lancashire. The position of the Hillhouse coastline in the area between Hundred End and Holmeswood (previously surmised) has now been determined, and the estuary of the extended river Yarrow confirmed. The boundary between Shirdley Hill Sand and Down‐holland Silt beach deposits is more exactly known than heretofore, and the positions of overlap of these deposits are studied. The overlying peat is divided into different types in accordance with the physical conditions prevailing during the period of its formation, and the distribution of forestal remains is mapped. Intervening river Alt alluvium is found in the district east of F

ISSN:0072-1050    

DOI:10.1002/gj.3350020106

出版商:John Wiley&Sons Ltd    

年代:1961

数据来源: WILEY

ISSN:0072-1050    

DOI:10.1002/gj.3350020107

出版商:John Wiley&Sons Ltd    

年代:1961

数据来源: WILEY

ISSN:0072-1050    

DOI:10.1002/gj.3350020108

出版商:John Wiley&Sons Ltd    

年代:1961

数据来源: WILEY

ISSN:0072-1050    

DOI:10.1002/gj.3350020109

出版商:John Wiley&Sons Ltd    

年代:1961

数据来源: WILEY

ISSN:0072-1050    

DOI:10.1002/gj.3350020110

出版商:John Wiley&Sons Ltd    

年代:1961

数据来源: WILEY

摘要:

AbstractViséan goniatites from the top of the P1Zone are described. Eight new species and one variety are erected. A new genusHibernicocerasis proposed for the reception of some of these. Observations are made on the genusPrædaraelitesof Schindewol

ISSN:0072-1050    

DOI:10.1002/gj.3350020111

出版商:John Wiley&Sons Ltd    

年代:1961

数据来源: WILEY