DETACHMENT OF FIRST-GENERATION CARBONATE CEMENT ON ONCOLITES BY CRYSTALLIZATION OF SECONDARY ANHYDRITE     

PETER ROTHE 《Sedimentology》1969,13(3-4):311-318

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Need for an Iron-Formation Reference Sample*     

PETER W. UITTERDIJK APPEL 《Geostandards and Geoanalytical Research》1980,4(1):19-19

An international iron-formation reference sample is warranted as a basis for geochemical investigations of Precambrian iron-formations. A better knowledge of the geochemistry of iron formations will hopefully elucidate the long standing discussion on the genesis of iron-formations. The reference sample can furthermore be used in studies of deep-sea metalliferous deposits.  相似文献   

THIN-SECTION SIZE ANALYSIS: A FURTHER NOTE     

PETER H. STAUFFER 《Sedimentology》1966,7(3):261-263

Criticisms by VAN DER PLAS (1962) of thin-section point counting as a method of size analysis appear to be based on confusion between number percent and volume percent. Points are samples of volume, and point counts yield volume percents. This is as much true of size classes as of other types of constituents, though distortions are caused in the distribution by the sectioning effect. The “ribbon” method advocated by Van der Plas counts individuals rather than points and hence yields number percents. The two types of statistic are fundamentally different.  相似文献   

Review     

PETER H. THOMPSON 《Journal of Metamorphic Geology》1986,4(2):231-233

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Anomalous luminescence of subglacial sediment at Haut Glacier d'Arolla,Switzerland – a consequence of resetting at the glacier bed?     

DARREL A. SWIFT  DAVID C. W. SANDERSON  PETER W. NIENOW  ROBERT G. BINGHAM  IAN C. COCHRANE 《Boreas: An International Journal of Quaternary Research》2011,40(3):446-458

Swift, D. A., Sanderson, D. C. W., Nienow, P. W., Bingham, R. G. & Cochrane, I. C. 2010: Anomalous luminescence of subglacial sediment at Haut Glacier d'Arolla, Switzerland – a consequence of resetting at the glacier bed? Boreas, Vol. 40, pp. 446–458. 10.1111/j.1502‐3885.2010.00196.x. ISSN 0300‐9483. Luminescence has the potential to elucidate glacial geomorphic processes because primary glacial sediment sources and transport pathways are associated with contrasting degrees of exposure to light. Most notably, sediment entrained from extraglacial sources should be at least partially reset, whereas sediment produced by glacial erosion of subglacial bedrock should retain substantial luminescence commensurate with a geological irradiation history. We set out to test the validity of this assumption at Haut Glacier d'Arolla, Switzerland using sediment sampled extraglacially and from the glacier bed. Contrary to our expectations, the subglacial samples exhibited natural signals that were substantially lower than those of other sample groups, and further (albeit limited) analyses have indicated no obvious differences in sample‐group luminescence characteristics or behaviour that could account for this observation. For glaciological reasons, we can eliminate the possibilities that the subglacial sediment has been extraglacially reset or exposed in situ to heat or light. We therefore advocate investigation of possible resetting processes related to subglacial crushing and grinding, and speculate that such processes, if more generally present, may enable the dating of subglacially deposited tills using luminescence‐based techniques.  相似文献   

Real world and real time political geography     

PETER PERRY 《New Zealand geographer》1987,43(1):33-34

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Reefs ancient and modern     

PETER ELLIS 《Geology Today》1986,2(2):41-42

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Factors influencing the mesoscale variations in marine stratocumulus albedo     

D. A. HEGG  K. NIELSEN  D. S. COVERT  H. H. JONSSON  P. A. DURKEE 《Tellus. Series B, Chemical and physical meteorology》2007,59(1):66-76

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Marriage-Distance Relationships in North Otago 1875–1914     

PETER PERRY 《New Zealand geographer》1969,25(1):36-43

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A mountain icefield of Loch Lomond Stadial age, western Grampians, Scotland   总被引：1，自引：0，他引：1  

PETER W. THORP 《Boreas: An International Journal of Quaternary Research》1986,15(1):83-97

The extent of a large mountain icefield that existed in the western Grampians during the Loch Lomond stade has been mapped. The main types of evidence used in establishing the limits comprise moraines, thick drift, fluvioglacial landforms, erratics, ice-smoothed bedrock, striae, friction cracks and relict periglacial forms. Trimlines on 198 spurs, and various forms of glacial and periglacial evidence on 73 cols and in c . 200 cirques, enable the upper limits and morphology of the icefield to be reconstructed. Abundant striae and friction cracks in many areas enable ice-flow directions and the surface form of the icefield to be inferred in some detail. The icefield had ice-shed altitudes of c . 750 m, a maximum width of 80 km and an area over 2,000 km². At least 60 nunataks stood above the icefield, and on its western side outlet glaciers reached the sea and flowed for as much as 28 km along major tidal water lochs.  相似文献