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During the Second World War, the Allied invasion of the French coast of Normandy on D‐Day, 6 June 1944, was the greatest amphibious assault in world history. An article in Geology Today (v.11, for 1995, pp.58–63) marked the 50th anniversary of the end of the war in Europe, on 8 May 1945, by describing how British military geologists had participated in planning for D‐Day and in the NW Europe campaign that followed it. The work of these geologists provides a classic case history, revealing that 'military geology' has many potential applications. Geological factors influenced site selection for temporary airfields, predictions of trafficability for the Normandy beaches, the development of potable water supplies, and quarrying for road metal—and more besides. This new article helps to mark the 75th anniversary of D‐Day by further details of how geologists and geology contributed to Allied victory. [ABSTRACT FROM AUTHOR]

Napoleon Bonaparte was in 1798 the first general to involve geologists as such in a military campaign. But geologists were attached to his army as civilians, without military rank or command function. In contrast, the Prussian general (later Field Marshal) Gebhard von Blücher has generally been credited with first making use of a geologist in military uniform: Professor Karl von Raumer, during the 1813–14 war of German liberation from French Napoleonic domination. Authors have claimed that Blücher consulted Raumer for information on the terrain of Silesia before triumphing over the French at the Battle of the Katzbach in 1813, and that Raumer was therefore the first geologist to help plan a military operation. But is this true? Did Raumer in effect initiate German military use of geology – pioneering the widespread use of geologists, many of them professors, in the 20th century German army? [ABSTRACT FROM AUTHOR]

Several geologists accompanied the army of Napoleon Bonaparte that landed in Egypt in 1798 – indicating that perception of the military value of geology is almost as old as Earth science itself. [ABSTRACT FROM AUTHOR]

Peritidal carbonates of the Lower Jurassic (Liassic) Gibraltar Limestone Formation, which form the main mass of the Rock of Gibraltar, are replaced by fine and medium crystalline dolomites. Replacement occurs as massive bedded or laminated dolomites in the lower 100 m of an ≈460-m-thick platform succession. The fine crystalline dolomite has δ18Ο values either similar to, or slightly higher than, those expected from Early Jurassic marine dolomite, and δ13C values together with 87Sr/86Sr ratios that overlap with sea-water values for that time, indicating that the dolomitizing fluid was Early Jurassic sea water. Absence of massive evaporitic minerals and/or evaporite solution-collapse breccias in these carbonate rocks indicates that the salinity of sea water during dolomitization was below that of gypsum precipitation. The occurrence of peritidal facies, a restricted microbiota and rare gypsum pseudomorphs are also consistent with penesaline conditions (salinity 72–199‰). The medium crystalline dolomite has some δ18Ο and δ13C values and 87Sr/86Sr ratios similar to those of Early Jurassic marine dolomites, which indicates that ambient sea water was again a likely dolomitizing fluid. However, the spread of δ18Ο, δ13C and 87Sr/86Sr values indicates that dolomitization occurred at slightly increased temperatures as a result of shallow (≈500 m) burial or that dolomitization was multistage. These data support the hypothesis that penesaline sea water can produce massive dolomitization in thick peritidal carbonates in the absence of evaporite precipitation. Taking earlier models into consideration, it appears that replacement dolomites can be produced by sea water or modified sea water with a wide range of salinities (normal, penesaline to hypersaline), provided that there is a driving mechanism for fluid migration. The Gibraltar dolomites confirm other reports of significant Early Jurassic dolomitization in the western Tethys carbonate platforms. [ABSTRACT FROM AUTHOR]