Bisbee daily review., 1918-01-20
Geology Of the Warren District

was the Juniper Flat Granite. This
 granite was tntuded into the old
 Pinal Schist before the Balsa Quart Zite was laid down. There are pieces of this granite in the bottom bed of the BOlsa It is a coarse crystalline, light cOlOred granite with a lot of quartz crystals. The only place you can find it is on Juniper Flat
 The next volcanic rock is the gran ite porphyry- This porphyry when fresh and unaltered is a birdseye DOT phyry. with a lot of quartz and a min eraI called OrthOclsse or felspar. and some mica This is the pOrphyry we get underground When it has been altered by the ore solutions and bOE gases. it is sometimes very hard 10 distinguish as the crystals of felspar and mica have been completely alter ed. and all you get is a few quartz crystals in a fine cOuract greenish grey rock. with considerable pyrite-
 There are three other vOlcan'e c rocks found in the district, but as they are not important and rare l will merely mention them: RhyOlite, An desite and Basslt- They only come in very small dikes, and have never been cut in any of our underground workings.
 Referring to figure 3. a geological map of the Mule mountains:
 You will see that the area can De divided up into several big blocks. bounded by faults In the first place, the whole range is cut in two by the dividend fault and its extension to the northwest This division coin cides with the main road, running from Forest ranch through Bisbee. to TOmb bstOne To the southwest of the road is exposed all the earliest rocks from the schist to the top of the Naco. On the northwest, on the other hand. is exposed the later Glance, MOrita. Mural and Cintura formations Being barren of ore, the study of the dis trict will be confined to the area southwest of the road The sediments as you will notice by the dip sizes are arranged fanfhape around the Juniper Flat granite area At each change of dip, there is usually a big fault You get through the Tomb stone block at the north, with the SC diments dipping to the north. then the Bisbee Extension block dipping to the northwest Then the Bisbee west block dipping from west to southwest then the EscabrOsa block dipping to the south and lastly the Copper Queen and Don Luis blocks dipping east.
 There are also two other blocks at the edge of the district. produced by big faults. which showed the earlier formations over the cretsceOus- These are the Gold hill and Glance blocks
 The important blocks from the standpoint of ores are the YOpperC Queen and Don Luis blocks. with the sediments dipping to the east anu northeast
 Referring to figure 4: This is geological map Of the Copper Queen and Don Luis blocks The Copper Queen block is bounded by three big faults. the Dividend on the north. the Quarry on the west. and the White Tail Deer fault on the south To the east the NacO limestone is covered by Glance oOnglOmerate- The Copper Queen block represents a dropped area. so that after the faulting it was lower than the surrounding country. Q sort of trough In this trough was intruded the Sacramento Hill DOT phyry and it's Offshouts- This particu- lar pOrphyry was a very wet intru- sion accompanied ana followed by a lot Of hot gases and hot water, which brought up our ores The DOT phyTy in the other blocks was 'dry and practically no ore came up with iL You only have to compare the red pcrphyry Outcroppins on Mt Ballard with the Sacramento Hill pOrphyTy tO see the difference Bes-ces the three big faults bounding the block the whole block is cut up with smaller ones the most important of which are the Car. Silver Bear and Oliver Faults Figures ,. and will give you some idea of the amount of fault ing through the block
 Referring again 10 figure l. I will run over the geologic history Of the camp again This is a vertical section taken through the Lowell shaft and Sacramento Hill, looking toward the west
 The first thing we have any rec ord of is the old schist land area which had been worn down to a near ly level plain, almost at sea level This is represented by the wavy green line The land then started 10 slowly sink. and we had. first the BOlsa quarIzite. then the AbrigO limestone. Martin. EssbrOsa. and NacO limestOnes laid down
 At the end of NacO time, there was a big upheavel the center of which was the old granite mass of Juniper Fiat and the whole area was intense ly faulted and broken up. Accom- panying this faulting there came up large amounts Of pOrphyry. one of the largest Of which. the Sacramento Hill pOrphyTy, came up along the dividend fault This pOrphyry unlike the rest was extremely wet" thas ls was accompanied by large amounts of lOc vapOrs and gases At the end of this period of faulting and intru- sion the surface al the section took the shape shown by the red line. a biz 3.9O0-fOOt cliff being To the north The probability is that besides the ore bodies as we have them nOw,