A study on sedimentary facies of Liuju member of Matoushan formation and forecasting of copper-bearing sand-body in Liuju area, Chuxiong Basin, China
|Location||International Geological Congress,oslo 2008|
|Author||Hu, Yuzhao۱; Min, Chaolong۲; Wu, Peng۱|
|Holding Date||11 October 2008|
Liuju sandstone-type copper deposit which controlled by sedimentary facies is one important stratified deposits in China.
There is a sedimentary typical dualistic structure in Liuju member of Matoushan Formation (K2ml).K2ml1 is believed as fluvial bottom deposit, include resort and point bar. It is composed of fine to coarse grained sandstone and conglomerate, constructing 6 half rhythmic sedimentation which become fine from bottom to upper. In base of conglomerate bed, erosion structure often occurres.K2ml2 and K2ml3 is believed as fluvial upper deposits which is products of vertical accretion of fluvial suspended loads, consisting of crevasse splay and fluvial lacus. Classically, prospecting line150 where 3 holes were drilled show us incised valley existing in the bottom of Liuju member of Matoushan Formation, which widens 135 meter and deepens 15meter (not recovered).
Based on the sedimentary facies and sequence of strata column of holes and ground, we use the theory of base-level cycle to contrast the high resolution sequence stratigraphy and the subfacies-microfacies ,then forecast the distribution of Copper-Bearing Sand-body in Liuju.
The dominated subfacies indicate that the fluvial and floodplain occurred in the age of K2ml1.The fluvial runs through floodplain and laterally sediments west. The bearing-copper sand body is in the Westside of fluvial.