2000 tracker oil problem. Where is it going? What can i do?

Hello, I have 2000 Chevy Tracker 2.0, manual trans. It does not leak or burn oil, but my oil level will go down after about 1200 miles after an oil change. About close to a quart. Where is it going? Should I change oil viscosity? I run Mobil 1 5000. 5w-30. I don't want to change to synthetic because I don't want any oil leaks to occur. Any info would be appreciated! Thanks!

Ok, I have an update. I have noticed that my valve cover gasket looks to be leaking. Still no drips on the ground. Is it possible it burns up before dripping off the engine? 965 miles after an oil change and I am down about 1/4 on the dipstick. I revved it up and had someone look to see if it smokes. Nothing! Is the valve cover gasket easy to replace? Any suggestions please.

Ok, I have an update. I have noticed that my valve cover gasket looks to be leaking. Still no drips on the ground. Is it possible it burns up before dripping off the engine? 965 miles after an oil change and I am down about 1/4 on the dipstick. I revved it up and had someone look to see if it smokes. Nothing! Is the valve cover gasket easy to replace? Any suggestions please.
My 2000 Tracker had a similar issue. I simply tightened up the valve cover bolts (they were not very tight to start wtih) and no more leak. Otherwise, changing the gasket is probably not to difficult.