Codzo River Cave [Grotte de la Rivière Codzo]
-18.564722,34.866667
Location
Codzo village, Codzo zone, Cheringoma district, Sofala province, 34°52'00'’E: 18°33'53"N (GPS WGS84), ca. 220 m asl.
Description
General description
Length: 942 m. Vertical range: -33 m. The cave is briefly described in Cilék (1989) as ,,...The Codzo deposit is made up of nummulitic limestones, 40 m thick, around the rapids of the river Codzo, which is partly subterraneous, partly flowing through a canyon and caves...“ Codzo River Cave was never expressively mentioned by the former guano prospectors. The Codzo river - a tributary to the Muanza river - enters a SW-NE running meandering gorge of about 40 - 50 m depth a short distance after it enters the limestone plateau coming from the east. The river carries water throughout the whole year. The direction of the gorge is clearly controlled by tectonic structures (SW-NE and SE-NW). The river gorge is partly roofed, forming caves of the above-mentioned ,b)-type". The hydrological function of the cave is to drain an allochtoneous catchment area. Its role as a collector of locally precipitated water is secondary but there are at least two inlets from the W (,Reptile Inlet" and ,,Our Pool Inlets") which contributes to the main streamway. Thus, taking into account the recent uplift of the Cheringoma plateau, the cave can be interpreted as a tunnel cave. Daylight shafts and collapse openings as well as Karstgassen give access to the main streamway of Codzo River Cave. The water of the stream was sampled and analysed because the cave is the only one which is used by the locals for sporadically water supply. The temperature of the subterranean stream is relatively low (19° C). This makes it difficult to survey the cave without rubber boats, although most of the deep lakes can be negotiated by swimming and several up till 6 m high rimstone barriers can be climbed. A big bat colony lives in the most Spart of the river cave. Bat droppings and decomposing bat corpses contaminates the water badly. In its eastern extensions the Codzo River Cave has an upper, fossil level of the ,a)-type". It contains a few calcite deposits and calcarenite infillings as well as some bat guano deposits. This part of the cave presumably is of preMiocene/Pliocene origin and was later filled with sediments during a marine transgression. Finally, the cave passages became reactivated in Quaternary times as a result of the downcutting of the Codzo gorge. Codzo River cave has a rich cave fauna. Beside several bat species and a big bat colony living in the southern part of the cave a big lizard and a dead python snake were observed. Many insects and other small animals were collected. Most of them are not determined yet.
Rio Codzo
Rio Codzo, a tributary of Rio Mazamba, begins with a narrow gorge in which, for about 1 km, open and roofed parts are alternating. For almost the whole gorge karst morphologies such as calcite gours, notches of corrosion on the walls and stalactite and stalagmite deposits are present. In the right mid sector some fossil galleries are present forming an upper level in comparison with the current erosion base level of the stream. In such sector the galleries show a bell shaped cross section, with palaeo-notches on the walls and ceiling channels in the top. Remains of fillings like pseudobreccias are also present in this sector. From the hydrological point of view, the gorge drains a series of Small tributaries situated in the left bank of Rio Codzo. Both the active part and the fossil system are developed along a system of structures N 45-60° and N 150–160°. The above-mentioned system and the secondary systems of fractures are shown in fig. 31: 1) N 45-60°, N 135-150°, N 150-165° - principal system of drain respectively with 33,8 %, 24,9 % and 23,6%; 2) N 15-30°, N 30-45° and N 120–135° - secondary system respectively with 9,1%, 4,5 % and 4,1 %.
Biospeology
Musks, Adianthum and Cyperaceae cover the banks of the gorge. The temperature of the water was 20.5°C, the pH 7.18 and the conductibility 736 puS. In the water of the gorge many aquatic animals such as Hemiptera (Hydrometridae and Gerridae,), aquatic Coleoptera (Girinidae) and larves of Ephemeroptera. Besides Amphibia Anura, fishes of small and medium dimension were present, Both inside the gorge-cave and in the fossil part a large colony of bats was present. The inside temperature was 23.4° C, and the relative humidity 64%. The ground was dry and dusty, covered by branches and leafs under which there were many Blattidae and Isopoda, while on the walls Orthoptera Raphidophoridae and Arachnida Amblypygi.
Documents
Codzo River Cave 15/11/2015
Cavités proche
| Distance (km) | Nom | Longueur (m) | Profondeur (m) |
|---|---|---|---|
| 0.1 | Upper Codzo River Cave | 40 | |
| 0.1 | Ninga Cupicua | 4 | |
| 0.1 | Mazamba Valley Caves | ||
| 0.4 | Ninga Niamabawa | 130 | 10 |
| 1.5 | Eastern Codzo Cave | 156 | 22 |
| 2.1 | Smaller Eastern Codzo Cave | 40 | 10 |
| 2.2 | Western Codzo Cave | 612 | 33 |
| 6.1 | Ninga Miriango | 610 | 10 |
| 7.7 | Ninga Manguenje | 188 | 10 |