This is Mazon Monday post #23. What's your favorite Mazon Creek fossil? Tell us at email:[email protected].
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In Mazon Monday #10, we discussed localities where siderite preservation of Pennsylvanian fossils has been found. There were a few localities listed. Here is more information about the site called Crock Hey (also Crockhey). This site was located near Lancashire in England. It was a temporary coal pit. The pit was located between Liverpool and Manchester in the north of England. Just like Mazon Creek, fossils in this quarry are found in concretions of siderite. Many of the plants and animals are similar and even identical to those found in the Mazon Creek deposit. Unfortunately, the coal mine was only open for about 10 years and has since been recovered. The fossil deposit was in a layer of shale just above the Wigan Coal. Age of the stratigraphy is Westphalian A in the Late Carboniferous. This corresponds to 313 to 304 million years ago. Recall, Mazon Creek occurred around 307 million years ago.
The coal from the Lancashire Coal Field has been extracted for many years. Sometimes this is done in underground mines, but also often in opencast coal pits. In the former case the life span can be long, like the Bickershow mine, which was closed down in 1992 after having yielded coal for more than 150 years. In the latter case the life span is much shorter: mostly less than 10 years. When the concession has been exhausted, the quarry is filled up and made ready for new landscape (building houses included). Click here for SandyForth Opencast.
An example of such a temporary coal pit is Crock Hey (also called Crockhey), which is situated between Liverpool and Manchester, not far from Wigan. This quarry yielded coal for 8 years and has been closed down recently. The pit has been filled in and soon the memory of the big hole will fade away. But not in the mind of the paleontologists!
In the quarry, concretions of siderite (an iron compound) occurred in which plants and small animals from the coal swamps of the Late Carboniferous (Westphalian A) have been preserved in exceptionally good quality. A couple of local amateurs have collected these nodules during the life span of the quarry and they have built up wonderful collections. With one of them, Steve Livesley from Lowton, I have come in contact through my website. With him, my wife and I have collected in the quarry during its last days. We have found there several nice fossils, but they pale before Steve's splendid collection.
Below is a choice of his plant fossils. The photos are mine.
Asterophyllites equisetiformis in a siderite nodule. Crockhey, Westphalian A. Width of the photo 9.5 cm.
Asterophyllites longofolius in a siderite nodule. Crockhey, Westphalian A. Width of the photo 10 cm.
Lepidodendron lycopodioides. Width of the photo 12 cm. Leaflets not S-shaped, broad at the base. Crockhey, Westphalian A.
Pecopteris sp. Crockhey, Westphalian A. Width of the photo 6.5 cm.
Cyperites, a leaf of a clubmoss tree. Two corresponding nodules! Crockhey, Westphalian A. Width of the photo 10 cm.
Lepidostrobus sp., the spore cone of a clubmoss tree. Crockhey, Westphalian A. Width of the photo 11 cm.
Laveinopteris loshii, a seed fern. Crockhey, Westphalian A. Width of the photo 9.5 cm.
Neuropteris jongmansii, a seed fern. Crockhey, Westphalian A. Width of the photo 11.5 cm.
Mariopteris muricata, a seed fern. Crockhey, Westphalian A. Width of the photo 7 cm. Coll Hans Steur
Cordaianthus, the fructification of Cordaites. Crockhey, Westphalian A. Width of the photo 4 cm.
Euproops rotundatus from Crockhey, Westphalian A Collection and photo: Andrew Tenny.
Palaeoxyris sp. from Crock Hey. Westfalian A. Supposed egg case of a shark. With spirals. Coll. and photo: Andy Tenny
Myiapod from Crockhey, Westphalian A Collection and photo: Andy Tenny.
