I have two dicth cutting samples of loose sands containing a lot of discrete calcite rhombs (occasionally broken). I am wondering if the cacite could be detrital or authigenic and if it could have any effect on the reservoir quality (especially, porosity and permeability) of the sand. What do you say?
First of all have you tested the 'rhomb' if it is true calcite or dolomite? I am curios because there is not much description given on the loose sands. Calcite tends to be 'broken-up' or erroded faster than silicate, if the clacite minerals originated from same sediment source as the sand (which I assume loose quartz), this is very unlikely if the quartz shows rounded and good sorted grained, because it has undergone alot of erosion and modification during sediment transportation. Unless the calcite you've found are from different depths due to improper depth lag correction (I assume your ditch cuttings are from well drilling). However, there is also a possibility for the calcite to formed as mineral inclusions in fractures and veins within a possibly quartzite unit? In the case of mineral inclusion of fractures/veins, it could be either calcite or dolomite (pls do check) and of course poro perm will be effected, how much? You need to do some petrography work if you have the core, to see minerals formation and diagenesis in the fractures how much pore spaces and pore necks left in the formation. Calcite and dolomite behave differently to weathering and degenesis, hence controls the poro perm quality of the rocks.
go to the nearest 99 cent store / car parts or whatever and buy a 3 dollar can of fix a flat foolow instructions poof in 5 mins its fixed or simply go to bike shop buy a tube and install it!
I am sorry, but i am not an environmental geologist. I am into structural and planetary.
Spray soapy water all over it ( the rim also ) to locate the leak.
