The geology of the northern part of the English lake districtQuarter sheet 101 SE(Including sheets 63, 64, 69, 70, 71, 76, and portions of 54, 55, 56, 57, 62, 65, 68, 73, 74, 75, Cumberland, and 12, 18, 19, Westmoreland, on the scale of six inches to a mile) . ng the planesof cleavage is often well-marked. I think then it may be concluded that the Skiddaw Slates andthe Volcanic Series were both cleaved at the same time and by apressure acting in a N. W. and direction; also that much of thefoliation was either an extension of the same process or took placesubsequently in the direction of t
The geology of the northern part of the English lake districtQuarter sheet 101 SE(Including sheets 63, 64, 69, 70, 71, 76, and portions of 54, 55, 56, 57, 62, 65, 68, 73, 74, 75, Cumberland, and 12, 18, 19, Westmoreland, on the scale of six inches to a mile) . ng the planesof cleavage is often well-marked. I think then it may be concluded that the Skiddaw Slates andthe Volcanic Series were both cleaved at the same time and by apressure acting in a N. W. and direction; also that much of thefoliation was either an extension of the same process or took placesubsequently in the direction of the cleavage planes, as those ofleast resistance. This intense lateral pressure, while producingcleavage both in the Skiddaw and Volanic Series, affected the twoformations differently as regards contortion; in the one case itcrumpled the beds, except where much banded by sandstone; inthe other it threw them merely into a series of low curves. noted this in 1836 (App. No. 16), and says, this factmight appear inexplicable, but we find a solution of our difficultyin the enormous irregular masses of hard unbending felspathioand porphyritic rocks, imbedded in, and so intimately mixed with,the green quartzose slate. • App. 25 and .36. H ^-11 i. ?13 r 69 CHAPTEE XII. ORIGINAL RELATION OF THE FORMATIONSTO EACH OTHER, AND THEIR PHYSICALHISTORY. It is very unfortunate that in the whole of this area there areno clear sections showing an unfaulted boundary between theSkiddaw Slates and the Volcanic Series. One instance has beenmentioned of the interstratification of a thin band of SkiddawSlate among the traps of Eycott Hill, and Mr. Aveliae has foundat Black Combe, in the south -western part of the lake district, avery decided alternation of Skiddaw Slate beds with those of theVolcanic Series. Quite lately, also, Mr. Dakyns and I have metwith a very complete passage between the formations ia thedistrict immediately west of Shap ; in one place bands of beddedash among the mas
Size: 1871px × 1335px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1870, booksubjectgeology, bookyear1876
