Outcrop

“ He had never seen it before; it was two or three miles from the highroad and seemed to be a virgin wilderness. But on close examination he could see, with the eye of a boy bred in a mining district, that the wall of outcrop had not escaped the attention of the mining prospector. There were marks of his pick in some attractive quartz seams of the wall, and farther on, a more ambitious attempt, evidently by a party of miners, to begin a tunnel, shown in an abandoned excavation and the heap of debris before it. ”

“ Sometimes, where a rupture exists, and one part of an outcrop has fallen below the other, the grooves are continued on the lower half; frequently the lines are crowded together like rulings on a page, and again the groove is of irregular depth, its floor rising and falling as though hitches had occurred when it was first planed, the great chisel meeting resistance, or being thrown up at points along its path. ”

“ If the outcrop of the reservoir be notably above the site of the well, and if it be kept full by frequent rains, the “head” will be strong, though the water at the well will not rise to the level of the outcrop of the reservoir. Experience has shown that an allowance of about one foot per mile of subterranean flow should be made. ”

“ Information of this sort obtained by surface exploration is often as conclusive as similar information obtained from underground workings. If the deposit shows great variations in thickness in its outcrop along the surface it is probable that a drift or a slope would show the same thing in depth. If the workable areas are poor, and appear only at long intervals along the outcrop, the chances of discovering richer areas by a shaft are very small. ”

“ Then they terminate at an angle in the outcrop of the ledge along the hillside. The appearance and condition of the upper strata, together with this narrow separation of the side walls outside the cave, produce the impression that at a period not very remote the roof of the cavern reached to the outcropping ledge in which the walls end. Even though the rock floor should be at the great depth supposed there is a possibility that an earth floor could be found below the detritus which has accumulated since the roof fell in or has worn away. ”

“ In all cases the outcrop (after the degradation of the upthrow side) is shifted down dip.
Fig. 437.—Same as Fig. 436, after (1) displacement by a strike fault and (2) base-leveling. The outcrops of certain beds are repeated. Fig. 438.—Diagram illustrating how a strike fault in such a structure as that shown in Fig. 436 may cause the outcrop of certain beds to disappear. Fig. 439.—Diagram illustrating how a dip fault in the structure shown in Fig. 436 affects the outcrop when the downthrow was on the farther side of the fault-plane. Fig. 440.—Same as Fig. ”

“ This163 hole being so small and its walls slanting, the only way to accomplish the first half of the descent was to sit down in the mud and slide, stopping half way to examine a fine ledge of beautiful striped onyx, white and a brownish pink, the first outcrop in the cave, but in the next level it is seen in rich abundance and variety; the colors being red, black and white, brown in several shades and pure white. All are handsome and of commercial quality and hardness ”

“ The principal bed of soft rock which outcrops along the line of the Waterpocket flexure is the Flaming Gorge shale, having a thickness of more than one thousand feet. Through nearly the whole extent of the outcrop a valley is carved from it, but the valley is not a unit in drainage. ”

“ If the axis of an eroded anticline were horizontal, a given hard layer, the arch of which has been cut off, would, after erosion, outcrop on both sides of the axis. When the topography was mature these outcrops would constitute parallel ridges, or parallel lines of hills; when the region had been base-leveled, the outcrops would be in parallel belts, though no longer ridges or hills. The lower the plane of truncation, the farther apart would the outcrops be in the anticline, and the nearer together in the syncline (compare ab and cd, Fig. 133) . ”

“ The minute hachures in figure 19 are drawn on the outcrop side of these ridges. Now suppose a general elevation of the region, lifting the synclinal troughs of the hard beds up to baselevel or even somewhat above it. The deepening of the revived master-stream will be greatly retarded by reason of its having to cross so many outcrops of the hard beds, and thus excellent opportunity will be given for readjustment by the growth of some diverting stream, B, whose beginning on adjacent softer rocks was already made in the previous cycle. ”

“ It rarely exceeds a quarter of a mile, and is [19] generally very much less, often not more than 100 to 200 feet. The next modification of outcrop, represented in Fig. 12, is one not uncommon on the south side of the Tertiary district. The strata b here crop out on the slope of the chalk hills, and the rain falling upon them, unless rapidly absorbed, tends to drain at once from their surface into the adjacent valleys. V, L, shows the line of valley level. ”

“ Everything we're seeing so far is either the outcrop itself and some of the stuff that's fallen down. Some that's fallen has fallen from the outcrop and some maybe from above. We can't tell with the granules in the crater in front of us, their pedigree is unknown. That's the nice thing about the spherules in the outcrop. You know where they come from. The evidence suggests that the highest concentration of hematite comes from up above the outcrop layer that we're not gonna see until we start to climb out of this crater. ”

“ Its outcrop was carefully examined for many miles along the mountain sides with the hope of finding a locality where conditions had been favorable for (a) the presence of life during deposition of sediments, (b) the subsequent changing of sediments into rock, and (c) the preservation of the rock during the vicissitudes consequent on mountain building, so that the preservation of the life of the epoch would be as complete as possible. ”

“ On the second ledge, or outcrop of hard rock below the summit of the cliff, on which ruin A stands, there is a fine example of the dug-out type of habitation, several of which occur in the sides of this canyon. The roof of this type of dug-out is formed by a flat slab of rock projecting horizontally from the cliff and forming the protection for a chamber excavated in the soft rock below. In some instances these dugouts have rudely constructed lateral and front walls but none of them has more than one room. They appear26 to have been inhabited rooms but may at times have served for shelter. ”

“ That no one has as yet stumbled upon them did not strike the lad as strange, for he knew that those who stalked through this wilderness were, for the most part, ignorant trappers or Indians, who would not know the value of a find if they fell over the richest outcropping ever found. ”

“ The main thing that I'm getting out of this is that there are several components to this soil and they're unevenly distributed around the crater and who knows what's outside of the crater. that could get even more interesting.
Q. Intriguing things is some seemed to be layered, a rich hematite above bedrock, some seems much patchier.
Steve: Fine particles can be blown by the wind. Little round particles can roll. I'm interested in concentration of these little guys as we get closer to the outcrop. Are they coming from the outcrop? Maybe they're weathering and falling out of the outcrop. ”

“ Outcrops of rock, in large snow couloirs, on ice or snow slopes, often appear as welcome islands in a long labour of step-making. But outcrops are apt to be more or less disintegrated, according to the character of the rock. If they are not rotten, they are not unusually rubbed bare and holdless by the passage of ice, stones and snow over them. Such islands, on ice slopes, are nearly always encircled by harder ice for a space round their lower walls, which increases our labour in approaching or leaving them. On their upper side they sometimes support a convenient spit of good snow. ”

“ These features have a general trend across the country from south-west or west to north-east or east—a direction determined by the successive outcrops of the different formations. But the denudation of the surface has been so great and so unequal that, despite the continuity and parallelism of the formations, their outcrops have been worn into endless diversities of topographical detail, producing abundant variety among the gentle profiles of the landscapes. ”

“ The place where any stratum makes its appearance on the surface is called its out-crop; and as they range themselves there in regular succession, you must at once perceive that in examining the surface, in a direction crossing the strata, you would find as complete a section of them as you now see in the face of the cliff, or as you could obtain by boring perpendicularly through them.”
He said a great deal more on this subject, and helped us to follow with our eyes several other strata to their out-crop. “This circumstance,” he added, “is of immense importance to the geologist ”

“ A few timbers scattered about, a rotten old stump that had served as part of the foundation, the hopper washed up by the waters, several of the posts which had upheld the race, were all that was left of the old mill, so long the salient feature of the place that more than one mountaineer was beset with bewilderment at the sight,—the recollection of the oblique line of the roof against the mountain, the open door, the reflections in the water, having more reality than the bereft bank of the river. ”

“ Like the drilling and blasting, axe work and cabin building were unfamiliar crafts, to be learned only at a round price paid in the coin of aching backs, stiffened muscles and blistered palms. Nevertheless, at the end of a toiling fortnight they had a one-room cabin roofed in, chimneyed and chinked with clay, a rude stone forge built for the drill sharpening and tempering, and a charcoal pit dug, filled and fired to provide the forge fuel. ”

“ There is a vast area of broken stone; groups of workmen applying themselves with pick and shovel; iron cars drawn by mules moving here and there; and the noise of incessant labor. Across the excavation stands a great wall, fifty feet high, split down the middle as though by a stroke of lightning. ”

“ A narrow path, winding and steep, and bordered here and yonder by precipices, leads up to the first fortified enclosure, whose ramparts, thirty feet high by two feet thick and flanked with large towers of brick, constitute one mass with the rock that serves as their foundation, a rock hewn with the pick and surrounded by abysses. ”

“ Others crowd up close to the street, utilizing the fortress-like slope as a combined wall and floor. Others mount the proud eminence of an ash-heap perhaps twenty feet high, a relic of abandoned dumping-grounds. Almost every yard of space is occupied. ”

“ In this chamber, whose walls, floor, and roof are formed of gigantic blocks seemingly on the point of collapsing, is an opening in the roof, through which a stream comes tumbling in. At the farthest corner therefrom a large opening leads to the bottom of a chimney or aven. Great quantities of clay on walls and roof show that this cavern has frequently been filled with water through the choking up of the lower exit. The stream runs away into the rocky floor at the lower end of the cave, and a few feet above it is a flood-way, a short, low tunnel, through which we crawled. ”

“ In the Eastern story, the heavy slab that was to fall on the bed of state in the flush of conquest was slowly wrought out of the quarry, the tunnel for the rope to hold it in its place was slowly carried through the leagues of rock, the slab was slowly raised and fitted in the roof, the rope was rove to it and slowly taken through the miles of hollow to the great iron ring. ”

“ Through holes in the roof the fog was dripping, hitting the hot top of the lantern with a sputter or streaking down the un-rinded timbers that held together the aperture-filled walls. Underfoot a slab floor bowed and sprung to the tread, a bare floor, knotted, uneven, yawning with two-inch cracks, littered with its own bark that the foot skinned off at every step. ”

“ Under the worst conditions of excavation in a hard cemented gravel it may be necessary to provide each man with a pick as well as a shovel, whereas in sand only a shovel is necessary. Two or three crowbars, axes, a length of chain, two or three screw jacks, etc., are provided per gang in case of an unexpected encounter with an obstruction in the trench, such as a boulder, a tree stump, a length of pipe, etc. ”

“ Should hops, or any other under-crop, be designed to be raised, it will be requisite to trench the whole of the ground; but, in either case, the spade must be carried to the depth of the natural soil. ”

“ An excavation is made below the level of the dining room to a depth of about two feet, and, after the ground has been rammed down, the mass of broken stones or the pounded burnt brick is spread on, at such an inclination that it can find vents in the drain. Next, having filled in with charcoal compactly trodden down, a mortar mixed of gravel, lime, and ashes is spread on to a depth of half a foot. ”

“ This roof covers a circular hole about ten or twelve feet in diameter, and just high enough for a man to stand up in. It is reached by a covered way from the main building, and its object was this:—When the reds were numerous and daring enough they had not much difficulty in setting the building on fire by throwing torches and blazing arrows on the roof, just as they threw them into our camp the other day. Then the stage people got into the ‘dug-out,’ and with plenty of rations and ammunition could hold their own indefinitely against all comers. ”