Difference Analysis of Organic Matter Enrichment Mechanisms in Upper Ordovician-Lower Silurian Shale from the Yangtze Region of Southern China and Its Geological Significance in Shale Gas Exploration

Figure 2

Shale cores from the X-1 well and Y-1 well. (a) Upper Ordovician Xinkailing Formation, 1360 m, Y-1 well, black siliceous shale; (b) upper Ordovician Wufeng Formation, 2523 m, X-1 well, black siliceous shale; (c) upper Ordovician Xinkailing Formation, 1362 m, Y-1 well, grey siliceous shale; (d) upper Ordovician Wufeng Formation, 2523 m, X-1 well, black siliceous shale with a large amount of graptolites; (e) no. 1 member of the lower Silurian Lishuwo Formation, 1336 m, Y-1 well, organic rich shale; (f) no. 1 member of the lower Silurian Longmaxi Formation, 2520 m, X-1 well, organic rich shale; see Figure 1 for the location of the outcrop and well site.

(a)

(b)

(c)

(d)

(e)

(f)